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ARTICLE
Transboundary Implications of China’s
Weather Modification Programme
Manon Simon,* Jan McDonald** and Kerryn Brent***
Abstract
In recent years, China has expanded its national weather modification programme to exploit
climatic resources and adapt to climate change. The unprecedented scale of China’s weather
modification programmes has raised concerns over potential environmental impacts, includ-
ing transboundary impacts. This article analyzes the domestic governance of weather modi-
fication in China and the extent to which this legal framework satisfies China’s obligations
under customary international law to minimize risks of significant transboundary harm.
We find that existing arrangements do not satisfy procedural obligations under customary
international law; nor do they adequately address the risks of environmental impacts asso-
ciated with the increased use of weather modification. Procedures for transboundary environ-
mental impact assessment (EIA) and engagement with regional neighbours are needed for
China to comply with international law and promote stability in the region.
Keywords: Weather modification, Atmospheric water, Cloud seeding, Climate change adap-
tation, Transboundary impacts, Chinese law
1.
China is implementing a large-scale programme of cloud seeding, which has attracted
media attention worldwide.
1
In 2022, China experienced the most severe summer
* University of Tasmania, Faculty of Law and Centre for Marine Socioecology, Hobart (Australia).
Email: manon.simon@utas.edu.au.
** University of Tasmania, Faculty of Law and Centre for Marine Socioecology, Hobart (Australia).
Email: jan.mcdonald@utas.edu.au.
*** University of Adelaide Law School, Adelaide (Australia).
Email: kerryn.brent@adelaide.edu.au.
The authors would like to thank Alexander Zahar for his feedback on earlier drafts and Charles S. Wang
for his assistance in obtaining relevant documentation.
Competing interests: The authors declare none.
1
‘China Deploys Rain-Seeding Drones to End Drought in Sichuan’,Bloomberg, 26 Aug. 2022, available
at: https://www.bloomberg.com/news/articles/2022-08-26/china-deploys-rain-seeding-drones-to-end-
drought-in-sichuan; Z. Hui, ‘At Least 10 Chinese Provinces Use Cloud-Seeding to Combat Heat
Wave; “No Effect”on Climate Change, Ecosystem’,Global Times, 26 Aug. 2022, available at:
https://www.globaltimes.cn/page/202208/1273964.shtml; Reuters, ‘China Deploys Cloud-Seeding
Transnational Environmental Law, page 1 of 29 © The Author(s), 2023. Published by Cambridge University Press
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/
licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
doi:10.1017/S2047102523000146
https://doi.org/10.1017/S2047102523000146 Published online by Cambridge University Press
heatwaves since records began in 1961. Daytime temperatures were above 35°C, lasting
for over two months.
2
The associated drought affected transportation, industry, food,
and hydro-electricity production for close to one billion people across 17 provinces.
3
In
response to these crippling drought conditions, China imposed tight water-consumption
restrictions and deployed aircraft and drones to seed clouds to enhance rainfall.
4
Weather modification by cloud seeding involves injecting particles –such as dry ice,
silver iodide or salts –into certain types of cloud to enhance precipitation or suppress
hail.
5
Depending on local geographical and meteorological conditions, cloud seeding
operations can be air-based, with particles delivered via aircraft or drones, or ground-
based using generators, canons or rocket launchers.
6
Developed by American scientists
after the Second World War, weather modification techniques focused initially on miti-
gating extreme weather events and increasing rainfall for agriculture.
7
In recent years,
cloud seeding has become a ‘long-term water resources management tool’
8
around the
world, to alleviate water shortages and enhance hydro-electricity production.
9
Some
states, including China, also use weather modification to mitigate hailstorms, although
the scientific evidence for hail suppression remains inconclusive.
10
Weather modification has been researched for over 50 years in China and other
countries, yet its environmental impacts remain understudied and poorly understood.
11
While weather modification techniques have obvious benefits, they also pose risks of
adverse impacts.
12
Altered precipitation patterns can affect plant and animal
communities, land structure, and hydrology.
13
In addition to the direct risks of weather
Planes and Cuts Electricity Use as Record Heatwave Takes Toll’,The Guardian, 17 Aug. 2022, available
at: https://www.theguardian.com/world/2022/aug/18/china-deploys-cloud-seeding-planes-and-cuts-
electricity-use-as-record-heatwave-takes-toll.
2
S. Mallapaty, ‘China’s Extreme Weather Challenges Scientists Trying to Study It’(2022) 609(7929)
Nature, p. 888.
3
D. Wong & H. Huang, ‘China’s Record Heatwave, Worst Drought in Decades’,South China Morning
Post, 31 Aug. 2022, available at: https://bit.ly/3AZUR3F.
4
E.T. Yeh, ‘Sky River: Promethean Dreams of Optimising the Atmosphere’(2022) 7(2) Made in China
Journal, pp. 96–101, at 96. See also S. Deng et al., ‘China Is Seeding Clouds to Replenish Its
Shrinking Yangtze River’,CNN, 18 Aug. 2022, available at: https://edition.cnn.com/2022/08/17/asia/
china-heat-drought-climate-yangtze-intl/index.html.
5
See generally V.J. Schaefer, ‘The Early History of Weather Modification’(1968) 49(4) Bulletin of the
American Meteorological Society, pp. 337–42.
6
X. Guo et al., ‘Advances in Cloud Physics and Weather Modification in China’(2015) 32 Advances in
Atmospheric Sciences, pp. 230–49, at 238.
7
See, e.g., V.C. Ball, ‘Shapingt he Law of Weather Control’(1949) 58 The Yale Law Journal, pp. 213–44,at 240.
8
WMO Expert Team on Weather Modification Research, ‘Report of the Expert Team on Weather
Modification Meeting’, 2015, p. 5, available at: https://community.wmo.int/en/wwrp-wx-mod.
9
A.I. Flossmann et al., ‘Peer Review Report on Global Precipitation Enhancement Activities’,
WWRP-2018-1, WMO, 2018, pp. 1–5, available at: https://library.wmo.int/records/item/42100-peer-
review-report-on-global-precipitation-enhancement-activities.
10
World Meteorological Organization (WMO), Statement on Weather Modification (WMO, 2015), p. 3,
available at: https://community.wmo.int/en/activity-areas/wwrp/wwrp-working-groups/wwrp-expert-
team-weather-modification.
11
Flossmann et al., n. 9 above, p. 16.
12
WMO, n. 10 above, p. 2.
13
C.F. Cooper & W.C. Jolly, Ecological Effects of Weather Modification: A Problem Analysis (University
of Michigan, Department of Resource Planning and Conservation 1969), pp. 120–2.
Transnational Environmental Law2
https://doi.org/10.1017/S2047102523000146 Published online by Cambridge University Press
modification, unsuccessful cloud seeding operations can increase the impacts of
droughts, floods and other weather disasters, for example, by increasing hail or redu-
cing precipitation.
14
The risk profile of weather modification differs depending on the scale and type of
seeding agent deployed. Some studies suggest that silver iodide could have accumulative
properties, with risks of persistence in the food chain and impacts on biological diver-
sity.
15
The United States (US) Weather Modification Association considers the annual
dispersal of three tonnes of silver iodide in Canada and the US to be environmentally
safe.
16
However, the World Meteorological Organization (WMO) Statement on
Weather Modification recommends that ‘any plans to use either a massive quantity
of such a product or a different seeding agent should be accompanied with a prelimin-
ary evaluation of its potential effects on both environment and human health’.
17
The
WMO is a United Nations (UN) agency, which facilitates information exchange on wea-
ther modification. The WMO Statement on Weather Modification articulates authorita-
tive but non-binding guidelines for conducting weather modification projects.
18
There are concerns, both within and beyond China, about the negative impacts of
weather modification at the scale of China’s expanding programme.
19
Weather modi-
fication activities could affect the regional distribution of rainfall, potentially depriving
downwind areas of their natural precipitation.
20
In some cases, weather modification
could also increase rainfall: studies demonstrate that seeding agents such as silver iodide
can seed clouds and thus enhance rainfall up to 200 kilometres (km) from the target
area.
21
Therefore, there is a clear risk of ‘extra-area effects’on ecosystems and
communities beyond the target area, including ‘the possibility of creating severe wea-
ther or floods’or ‘increasing rainfall in one local region at the expense of rainfall in
a neighbouring local region’.
22
Within China, this issue arose in the 2000s when
14
WMO, n. 10 above, p. 6. See also, W.R. Cotton & R.A. Pielke, Human Impacts on Weather and Climate
(Cambridge University Press, 2007), p. 250.
15
C. Fajardo et al., ‘Potential Risk of Acute Toxicity Induced by AgI Cloud Seeding on Soil and Freshwater
Biota’(2016) 133 Ecotoxicology and Environmental Safety, pp. 433–41.
16
See generally Weather Modification Association (WMA), ‘Position Statement on the Environmental
Impact of Using Silver Iodide as a Cloud Seeding Agent’, July 2009, available at: https://weathermod.
org/wp-content/uploads/2018/03/EnvironmentalImpact.pdf.
17
WMO, n. 10 above, p. 12.
18
World Meteorological Congress & WMO (eds), Fifteenth World Meteorological Congress, Geneva,
7–25 May 2007: Abridged Final Report with Resolutions (WMO, 2007), p. 54, available at:
https://library.wmo.int/doc_num.php?explnum_id=5225;WMO,‘Strategic Plan for the Implementation
of WMO’s World Weather Research Programme (WWRP): 2009–2017’(WMO, 2009), pp. 49–50, avail-
able at: https://library.wmo.int/doc_num.php?explnum_id=5758 (WMO Strategic Plan).
19
See, e.g., S. Pathak, ‘Adding Artificial Rain to the Sino-Indian Conundrum’,Asia Times, 10 Apr. 2018,
available at: https://asiatimes.com/2018/04/adding-artificial-rain-sino-indian-conundrum. See also
D. Jayaram & K. Bhattacharjee, ‘China’s Geoengineering Push Dangerous for the Region’,
The Sunday Guardian Live, 19 Dec. 2020, available at: https://www.sundayguardianlive.com/news/
chinas-geoengineering-push-dangerous-region.
20
R. List, ‘Weather Modification: A Scenario for the Future’(2004) 85(1) Bulletin of the American
Meteorological Society, pp. 51–64, at 57.
21
T.P. DeFelice et al., ‘Extra Area Effects of Cloud Seeding: An Updated Assessment’(2014) 135–136
Atmospheric Research, pp. 193–203.
22
Cotton & Pielke, n. 14 above, p. 250.
Manon Simon, Jan McDonald and Kerryn Brent 3
https://doi.org/10.1017/S2047102523000146 Published online by Cambridge University Press
local governments in provinces such as Henan, Guanxi and Shaanxi accused each other
of stealing precipitation (or ‘cloud theft’).
23
Of perhaps more importance are concerns that weather modification activities
could have detrimental impacts across national borders.
24
Controversy over
potential transboundary impacts of weather modification has persisted since the
1960s,
25
and these concerns continue to feed geopolitical tensions.
26
It is not the
purpose of this article to assess whether any of China’s weather modification activ-
ities have in fact caused, or are likely to cause, significant transboundary harm. A
claimant state would face major challenges in litigating a claim based on actual
harm because of the difficulties in establishing a causal link between a specific wea-
ther modification activity and any alleged transboundary harm.
27
It may be possible,
however, to demonstrate that the increased risk makes harm ‘likely’. With the present
state of science, it remains extremely difficult to demonstrate that weather modifica-
tion activities cause transboundary impacts (for example, disruption of regional cli-
mate systems, changes in transboundary watercourses). Yet, in accordance with the
precautionary approach recognized under international law,
28
these uncertainties
should not be used as reasons for postponing measures to prevent serious impacts
from occurring.
A prominent example of these concerns is the ongoing tension between India and
China over China’s‘Sky River’weather modification project on the Tibetan
Plateau.
29
Since 2016, Tsinghua University, Qinghai University, and the meteoro-
logical bureau of Qinghai province have been working on the Sky River Project
23
S. Chien, D. Hong & P. Lin, ‘Ideological and Volume Politics behind Cloud Water Resource Governance:
Weather Modification in China’(2017) 85 Geoforum, pp. 225–33, at 232.
24
See generally L.L. Roslycky, ‘Weather Modification Operations with Transboundary Effects: The
Technology, the Activities and the Rules’(2003) 16 Hague Yearbook of International Law, pp. 3–40.
25
See, e.g., R.J. Davis, ‘The United States and Mexico: Weather Technology, Water Resources and
International Law’(1972) 16(4) Natural Resources Journal, pp. 530–44, at 543.
26
See, e.g., Pathak, n. 19 above; ToI Staff, ‘Iranian General Blames Water Woes on Israeli “Cloud Theft”’,
The Times of Israel, 2 July 2018, available at: https://www.timesofisrael.com/iranian-general-blames-
water-woes-on-israeli-cloud-theft.
27
T. Majzoub et al., ‘“Cloud Busters”: Reflections on the Right to Water in Clouds and a Search for
International Law Rules’(2008) 20(3) Colorado Journal of International Environmental Law and
Policy, pp. 321–66, at 337–43.
28
As explained in Section 3below, all states are obliged under the no-harm rule of customary international
law to adopt a precautionary approach where there is scientific uncertainty concerning risks of significant
transboundary harm. While the precise framing differs across contexts, the most widely accepted formu-
lation of the precautionary principle provides that ‘[w]here there are threats of serious or irreversible dam-
age, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to
prevent environmental degradation’: Rio Declaration on Environment andDevelopment, adopted by the
UN Conference on Environment and Development, Rio de Janeiro (Brazil), 3–14 June 1992, UN Doc.
A/CONF.151/26/Rev.1 (Vol. I), 14 June 1992, available at: https://www.un.org/en/development/desa/
population/migration/generalassembly/docs/globalcompact/A_CONF.151_26_Vol.I_Declaration.pdf
(Rio Declaration).
29
C.L. Geros, ‘Drinking the Winds: Monsoon as Atmospheric Spring’(2021) 7(1) GeoHumanities, pp. 65–
88, at 81–2. See also S. Chen, ‘China Needs More Water: So It’s Building a Rain-Making Network Three
Times the Size of Spain’,South China Morning Post, 26 Mar. 2018, available at: https://www.scmp.com/
news/china/society/article/2138866/china-needs-more-water-so-its-building-rain-making-network-three;
this newspaper article was the first source to make information on the Sky River project available to an
English-speaking audience.
Transnational Environmental Law4
https://doi.org/10.1017/S2047102523000146 Published online by Cambridge University Press
(Tianhe in Mandarin),
30
in collaboration with a military contractor, the Aerospace
Science and Technology Corporation.
31
The project is expected to transfer up to
5 billion cubic metres of water annually from the Yangtze river, to feed the inland
river systems further north, including the Yellow river basin.
32
The Chinese
Meteorological Administration (CMA) has already installed more than 500 ground-
based generators to seed clouds over the Qinghai-Tibetan Plateau.
33
The generators
are activated by satellites that monitor and forecast meteorological conditions,
34
with further support announced in September 2022.
35
This experiment is intended
to be scaled up to tens of thousands of generators, covering an area of up to 1.6 million
km
2
.
36
However, because of the controversial nature of the project, information on the
Sky River project is scarce.
37
There are doubts that the scale of the Sky River project is feasible,
38
but more press-
ing are concerns that enhancing precipitation over the Himalayas for the benefit of
China may deprive India of beneficial rainwater.
39
The project has been planned
with little transparency or cooperation with neighbouring countries in South and
Southeast Asia, especially India.
40
These factors contribute to discomfort over what
is perceived by some to be the militarization of the Chinese weather modification
programme.
41
The rapid upscaling of China’s capacity to intervene in atmospheric processes under-
scores the need for robust laws to assess and mitigate environmental impacts across
30
G. Wang et al., ‘Study on Sky Rivers: Concept, Theory, and Implications’(2018) 21 Journal of
Hydro-environment Research, pp. 109–17, at 110.
31
Geros, n. 29 above, p. 81.
32
Q. Zhang & Q. Gu, ‘Sustainability Analysis of Cross-Regional Drinking Water Project in North and
South China Take West Route of the South-to-North Water Diversion and the Tianhe Project’(2019)
IOP Conference Series: Earth and Environmental Science, pp. 1–6, at 2.
33
Ibid.
34
G. Wang et al., ‘The Sky River Project’, International Association for Hydro-Environment Engineering
and Research, 2017, pp. 120–22, at 122, available at: https://henry.baw.de/server/api/core/bitstreams/
a01e5e16-fb25-4155-a778-99245374f7e9/content. See also E.M. Hunchuck, M. Ferrari & J. Cheng,
‘Prologue to the Sky River’,The Avery Review, June 2021, available at: https://www.averyreview.com/
issues/53/prologue-to-the-sky-river.
35
CMA, ‘The China Meteorological Administration Deploys and Promotes the Capacity Building of Weather
Modification in Southwest China’, 22 Sept. 2022, available at: http://www.cma.gov.cn/2011xwzx/
2011xqxxw/2011xqxyw/202209/t20220901_5065542.html?from=singlemessage&fbclid=IwAR1b5RSZFWz
6PJDPW9jIO-Wwm2wooh13ReL5DB_MiQFMpXdq28GAL6tyI-Q (in Chinese).
36
Chen, n. 29 above.
37
Yeh, n. 4 above, pp. 99–100.
38
See generally T.J. Xuan & W. Jiawen, ‘Qinghai-Tibet Artificial Rainfall Project “Delusional,”Experts
Say’,Caixin Global, 27 Nov. 2018, available at: https://www.caixinglobal.com/2018-11-27/qinghai-
tibet-artificial-rainfall-project-delusional-experts-say-101352671.html.
39
Pathak, n. 19 above; A. Jash, ‘China’s Practice of Weather Modification: Implications for India’,Centre
for Land Warfare Studies Issue Brief, Mar. 2020, available at: https://www.claws.in/static/IB-
125_Chinas-Practice-of-Weather-Modification.pdf.
40
Ibid.
41
‘China’s“Weather Modification System”Raises Alarm in Assam’,The Times of India, 29 Mar. 2018,
available at: https://timesofindia.indiatimes.com/city/guwahati/chinas-weather-modification-system-
raises-alarm-in-assam/articleshow/63527223.cms.
Manon Simon, Jan McDonald and Kerryn Brent 5
https://doi.org/10.1017/S2047102523000146 Published online by Cambridge University Press
provincial and international borders. The WMO notes that ‘legal aspects may be
particularly important when weather modification activities are performed in the prox-
imity of borders between different countries’.
42
This article investigates these issues. It
examines the way in which China currently governs its weather modification pro-
gramme, with a particular focus on whether its current assessment and monitoring
requirements satisfy customary international law obligations to avoid transboundary
harm. We show that detailed laws are in place to address the safety of weather modifi-
cation operations, but that limited consideration has been given to the risks of
transboundary environmental impacts. The analysis is based on a review of available
literature, combined with doctrinal analysis of officially translated Chinese laws, as
well as policies and plans translated using translation software.
43
The analysis proceeds in six parts. Following this introduction, Section 2outlines the
development and features of China’s weather modification programme. Section 3
considers China’s international law obligations, with a particular focus on obligations
to assess and prevent transboundary impacts under international customary law.
Section 4then evaluates whether the domestic regime governing weather modification
activities meets China’s international obligations to India and other neighbouring
countries. Section 5discusses the kinds of mechanism needed to ensure that China’s
weather modification laws comply with international requirements. We conclude in
Section 6that stronger safeguards are needed to address the environmental, social,
and economic risks associated with weather modification, both within China and
across national borders.
2. ’
China is the largest investor in weather modification deployment globally.
44
Since 2014,
governments at all levels in China have invested 13.267 billion yuan (CN¥) (or close to
US$ 2 billion) in weather modification activities, including about US$ 400 million
originating from the central government.
45
These activities have covered more than
one third of China’s total land area.
46
Atmospheric water resources are unevenly distrib-
uted across the country, with the south generally having more atmospheric water than
the north, leading to varying cloud seeding potential in different regions.
47
Cloud seed-
ing demand also varies depending on seasons, with most regions facing water scarcity
in spring and summer, and a few regions facing limitations in autumn and
42
WMO, n. 10 above, p. 12.
43
Translations were conducted by the authors from Mandarin to English using Google Translate. Wherever
the meaning was unclear, Baidu Translate (the Chinese search engine) was used to complement or refine
the first result.
44
WMO Expert Team on Weather Modification Research, n. 8 above, p. 5.
45
CMA, ‘National Weather Modification Development Plan 2021–25’(2021) (in Chinese) (2021–25
WMDP), para. I(1)(1) (translated by the authors from Chinese to English).
46
Ibid.
47
L. An et al., ‘Regional Characteristics and Exploitation Potential of Atmospheric Water Resources in
China’(2022) 42(5) International Journal of Climatology, pp. 3225–45, at 3227.
Transnational Environmental Law6
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winter.
48
While the number of research programmes is small,
49
most weather modifica-
tion activities are conducted on an operational basis, using cloud seeding techniques for
precipitation enhancement and hail suppression.
50
Both cloud seeding applications
involve the dispersal of silver iodide, although dry ice and liquid nitrogen can also be
used to enhance precipitation.
51
Weather modification is a manifestation of China’s attempts to harness atmospheric
water resources to ensure economic stability, alongside commitments to ‘fix the air’by
addressing atmospheric pollution.
52
The 2022 drought is the latest of many meteoro-
logical disasters in China, and the use of weather modification to mitigate heatwaves
is only one application of the Chinese programme. Over the past two decades, China
has deployed cloud seeding principally to increase freshwater resources and mitigate
the impacts of hailstorms on weather-dependent sectors such as agriculture.
53
The possibility of weather modification was first championed by Mao Zedong in
1956, with a research programme entitled ‘Prior Research on Cloud and
Precipitation Physics and Artificial Rain’.
54
The first weather modification experiments
were conducted in 1958 in northern and western China.
55
China’s extensive research
on weather modification continued for over 40 years, before operational planning com-
menced with the establishment of the National Coordination Committee of Weather
Modification
56
and the first Weather Modification Development Plan (1996–
2010).
57
The 2012 State Council’s‘Comments on Further Strengthening Weather
Modification’(known as Document No. 44) provided the legal basis for the next
Weather Modification Development Plan (WMDP) 2014–20.
58
The size, rapid up-scaling and breadth of weather modification in China is unprece-
dented.
59
As in other countries,
60
China uses weather modification to secure water
48
M. Kong et al., ‘A Nationwide Analysis of Water Scarcity and Cloud Seeding Demand Levels from
Analyzing Water Utilization Data, Agricultural Drought Maps, and Local Conditions in China
Mainland’(2021) 8(6) Earth and Space Science, pp. 1–18, at 14.
49
See, e.g., Chinese Randomized Precipitation Enhancement Experiment (CRPEEX): A.M. Abshaev et al.,
‘Rain Enhancement through Cloud Seeding’, in M. Qadar et al. (eds), Unconventional Water Resources
(Springer, 2022), pp. 21–50, at 44.
50
Guo et al., n. 6 above, p. 237.
51
Ibid., p. 237–9.
52
M. Nieuwenhuis, ‘The Governing of the Air: A Case Study of the Chinese Experience’(2016) 15(1)
Borderland, pp. 1–23, at 11.
53
Chien, Hong & Lin, n. 23 above, p. 229.
54
Ibid., p. 228.
55
Guo et al., n. 6 above, p. 231.
56
WMO Expert Team on Weather Modification Research, n. 8 above, p. 8.
57
Chien, Hong & Lin, n. 23 above, p. 228.
58
State Council of the People’s Republic of China, ‘Comments on Further Strengthening Weather
Modification’, Document No. 44, 30 Aug. 2012, available at: http://www.gov.cn/zwgk/2012-08/30/
content_2213785.htm (in Chinese).
59
See generally, Chien, Hong & Lin, n. 23 above; Chen, n. 29 above; J. Watts, ‘China Plans Rapid
Expansion of “Weather Modification”Efforts,’The Guardian, 4 Dec. 2020, available at:
https://www.theguardian.com/world/2020/dec/03/china-vows-to-boost-weather-modification-capabilities.
60
At least 50 countries are currently undertaking weather modification research, development, and deploy-
ment: WMO Expert Team on Weather Modification Research, n. 8 above, p. 3.
Manon Simon, Jan McDonald and Kerryn Brent 7
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resources for freshwater consumption and hydro-electric production, especially along
the Yangtze river in Yunnan and Sichuan provinces.
61
Weather modification, employed
for both precipitation enhancement and hail suppression, is also used to increase food
production and ensure food security, notably in the province of Jilin and the Yellow
river plain.
62
Beyond these conventional applications, the technology has also been used for
ecological restoration. For example, weather modification for precipitation
enhancement has been conducted in the Sanjiangyuan National Nature Reserve in
the province of Qinghai, to restore the headwaters of the Yangtze, Yellow and
Mekong rivers.
63
The 2014–20 WMDP promotes weather modification as a tool
to restore vulnerable ecological areas –such as rivers, lakes, glaciers and wetlands
–which have been affected by climate change, desertification, and biodiversity
loss.
64
It also claims that weather modification operations have increased the surface
of lakes and grassland coverage in the Tibetan plateau, thus creating a ‘green eco-
logical barrier’, which preserves those areas from economic development.
65
The Plan also promotes weather modification as a means to lower air temperatures
during heatwaves, and lower surface water temperatures in lakes to control the
proliferation of bacteria.
66
Cloud seeding can also improve air quality,
67
as increased rainfall ‘washes out’
harmful pollution from the air.
68
As part of its ‘blue skying’campaign,
69
China uses
weather modification to control sandstorms, reduce haze, and manage the health
risks of air pollution. Weather modification has also been used to secure fair weather
for important national events.
70
The 2008 Olympic Games is the best-known example
61
Chien, Hong & Lin, n. 23 above, p. 228.
62
Ibid.
63
Ibid., pp. 229–30.
64
National Development, Reform Commission & CMA, ‘National Weather Modification Development
Plan 2014–20’, 2014, para. 6(1) (in Chinese) (2014–20 WMDP) (translated by the authors from
Chinese to English).
65
Ibid., para. 6(1). It is worth noting that some non-governmental organizations, like the International
Campaign for Tibet, argue that the Chinese government’s claims of promoting ‘ecological restoration’are
inconsistent with the construction of infrastructure in Tibet –such as roads, railways, dams, mining projects,
and the bottled water industry –which have significant environmental impacts in the region; see, e.g.,
International Campaign for Tibet, ‘China’s Claims in New White Paper about Protecting Tibet’s
Environment Are Contradicted by Increased Production of Bottled Water from Shrinking Tibetan Glaciers,
More Dams’, 8 Aug. 2018, available at: https://savetibet.org/chinas-claims-in-new-white-paper-about-
protecting-tibets-environment-are-contradicted-by-increased-production-of-bottled-water-from-shrinking-
tibetan-glaciers-more-dams; ETC Group, ‘China’s Plan to Seed Himalayan Clouds Is Geoengineering:
Unintentional or Otherwise’, 8 Nov. 2018, available at: https://www.etcgroup.org/content/chinas-plan-
engineer-himalayan-clouds-geoengineering-unintentional-or-otherwise?language=en.
66
2014–20 WMDP, n. 64 above, para. 6(1).
67
Chien, Hong & Lin, n. 23 above, p. 230.
68
Flossmann et al., n. 9 above, p. 6.
69
S.-S. Chien, ‘Blueskying’,Society and Space, 9 Apr. 2019, available at: https://www.societyandspace.org/
articles/blueskying.
70
Chien, Hong & Lin, n. 23 above, pp. 229–31.
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of the government’s assertion of control over atmospheric resources for public
amenity.
71
In response to the International Olympic Committee’s threats to postpone
the event because of the high level of air pollution,
72
officials triggered rainfall to
clean the air and prevent the heavy rainfalls forecast over Beijing.
73
China’s use of wea-
ther modification for mega-events is only a minor aspect of the national weather
modification programme,
74
despite it being mentioned frequently in the literature.
75
However, this demonstrates that China uses weather modification not only to adapt
to climate change impacts, as is common in other countries, but to exert control over
atmospheric resources, extending its influence beyond its territorial resources such as
minerals and surface water.
76
Regardless of the purposes for which weather modifica-
tion activities are conducted, there are risks associated with their deployment on such a
large scale (for example, potential disruption of the hydrological cycle with effects on
people and the environment).
The 2014–20 WMDP was issued to ensure the smooth development of weather
modification technologies and bolster the management of weather modification.
77
While it provides a general summary ofthe potential environmental impacts of weather
modification, the Plan nonetheless considers it beneficial for the country’s sustainable
development. The Plan integrates weather modification in the framework of ‘ecological
civilization’, which broadly equates with the concept of ‘sustainable development’.
78
The 2014–20 WMDP identifies the main organizational challenges for weather modi-
fication, encompassing cross-regional operations, science-based decision making,
security, and responsibility.
79
These challenges are especially pertinent in the context
of multi-level and large-scale operations. The WMDP divides the country into six
administrative regions –Northeast, Northwest, North, Central, Southwest and
71
J. Qiu & D. Cressey, ‘Taming the Sky: Is It Really Possible to Stop Rain, Invoke Lightning from the
Heavens or Otherwise Manipulate the Weather? Jane Qiu and Daniel Cressey Report on the
Once-Scorned Notion of Weather Modification’(2008) 453(7198) Nature, pp. 970–5, at 972–3.
72
E. Stewart, ‘IOC Praises Efforts to Reduce Air Pollution in Bejing’,The Guardian, 7 Aug. 2008, available
at: https://www.theguardian.com/world/2008/aug/07/china.olympics2008.
73
M.W. Pontin, ‘Weather Engineering in China’,MIT Technology Review, 25 Mar. 2008, available at:
https://www.technologyreview.com/2008/03/25/270084/weather-engineering-in-china.
74
K. Edney & J. Symons, ‘China and the Blunt Temptations of Geo-Engineering: The Role of Solar
Radiation Management in China’s Strategic Response to Climate Change’(2014) 27(3) The Pacific
Review, pp. 307–32, at 320.
75
See, e.g., S. Joronen, M. Oksanen & T. Vuorisalo, ‘Towards Weather Ethics: From Chance to Choice with
Weather Modification’(2011) 14(1) Ethics, Policy & Environment, pp. 55–67, at 55; E.C. Smit,
‘Geoengineering: Issues of Accountability in International Law’(2015) 15(2) Nevada Law Journal,
pp. 1060–89, at 1073; K. Brent, J. McGee & J. McDonald, ‘The Governance of Geoengineering:
An Emerging Challenge for International and Domestic Legal Systems’(2015) 24(1) Journal of Law,
Information and Science, pp. 1–33, at 8.
76
See generally J. Chen & J. Cui, ‘Property Rights Arrangement in Emerging Natural Resources: A Case
Study of China’s Nationalization of Wind and Sunlight’(2013) 27(1) Columbia Journal of Asian Law,
pp. 81–127; Nieuwenhuis, n. 52 above; Chien, Hong & Lin, n. 23 above.
77
See generally 2014–20 WMDP, n. 64 above.
78
Ibid., para. 6. For a discussion of the Chinese ecological civilization see, generally, B. Boer,
R. Cantley-Smith & T. Qin, ‘Introduction to the Special Issue on Ecological Civilization and
Environmental Governance’(2020) 4(2) Chinese Journal of Environmental Law, pp. 121–9.
79
2014–20 WMDP, n. 64 above, para. 1(2).
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Southeast –as part of its commitment to strengthen ‘responsibility, information shar-
ing, and coordination’between state, province, city, and county levels.
80
Weather
modification activities are conducted in all regions for different purposes, which
include food, water, and ‘ecological’security.
81
In each region, one city is identified
as the centre of operations and its meteorological bureau is responsible for coordinating
cloud seeding operations at the regional level.
82
On completion of the 2014–20 WMDP, the Office of the State Council published its
‘Opinions on Promoting the High-Quality Development of Weather Modification’.
83
This document provided the foundation for the 2021–25 WMDP, and committed to
strengthen research, innovation, and operational capacity for weather modification.
84
Between 2014 and 2020, weather modification activities for precipitation enhancement
covered an area of 2.83 million km
2
, with an estimated 79.2 billion tons of
annual increase in rainfall and snowfall (or about 15% of the annual national water
consumption).
85
Weather modification coverage is expected to double by 2025
under the 2021–25 WMDP to cover over 5.5 million km
2
for rainfall/snowfall enhance-
ment, and 580,000 km
2
for hail suppression.
86
In total, these programmes will cover an
area that is 150% larger than that of India.
Like the earlier Plans, the 2021–25 WMDP emphasizes the importance of weather
modification for ecological restoration. This is in line with the Overall Plan for National
Major Ecosystem Protection and Restoration Major Projects (2021–2035), which identi-
fies key ecological areas, including the Qinghai-Tibet Plateau, and the Yellow and Yangtze
rivers.
87
The 2021–25 WMDP encourages snow enhancement projects in the Himalayas
to combat the retreat of the glaciers as a consequence of climate change.
88
The new
WMDP also encourages the automation of weather modification delivery methods,
especially the use of unmanned aerial vehicles (drones) and artificial intelligence.
89
Prominent scientists, such as Bruintjes, question China’s unsubstantiated claims
concerning the effectiveness of its weather modification activities.
90
Studies
80
Ibid., para. 3(1).
81
For a discussion of the weather modification administrative division see W. Gasser, ‘Let It Rain: Weather
Modification in Europe, USA and with a Special Focus on China’(Masters’thesis, Technische Universität
München (Germany), Mar. 2016), pp. 31–5.
82
Ibid., p. 78.
83
Office of the State Council, ‘Opinions of the General Office of the State Council on Promoting
the High-quality Development of Weather Modification Work’, 2 Dec. 2020, available at:
http://www.gov.cn/zhengce/content/2020-12/02/content_5566429.htm (in Chinese).
84
Ibid.
85
2021–25 WMDP, n. 45 above, para. I(1)(4).
86
Ibid., para. II(3). See also State Council, ‘China to Forge Ahead with Weather Modification Service,’
2 Dec. 2020, available at: http://english.www.gov.cn/policies/latestreleases/202012/02/content_WS5fc
76218c6d0f7257694125e.html.
87
2021–25 WMDP, n. 45 above, para. IV(1)(2).
88
Ibid., para. I(2).
89
Ibid., para. IV(2)(2–3).
90
R. Bruintjes, cited in B. Walker & O. Boyd, ‘China’s Geoengineering Plans Dismissed as “Fantasy”’,
China Dialogue, 11 Apr. 2013, available at: https://chinadialogue.net/en/climate/5891-china-s-
geoengineering-plans-dismissed-as-fantasy; Xuan & Jiawen, n. 38, above; L. Pike, ‘China’s Scientific
Transnational Environmental Law10
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demonstrate thatweather modification by cloud seeding is efficient only in the presence
of clouds, and that operations conducted as an emergency response in times of drought
are largely unsuccessful.
91
Regardless of its effectiveness, the deployment of cloud
seeding as an emergency response to the 2022 drought is the latest evidence of
China’s commitment to upscaling its national weather modification programme. The
scale of its plans raises questions regarding the adequate management of environmental
risks and associated socio-economic impacts.
3. ’
This section introduces the international law applicable to weather modification activ-
ities. We explain why the Convention on the Prohibition of Military or Any Other
Hostile Use of Environmental Modification Techniques (ENMOD Convention)
92
is
of limited use in providing safeguards for the peaceful use of weather modification,
before focusing on the no-harm rule as the only rule of international law that imposes
legal limits on China’s weather modification programme.
3.1. The ENMOD Convention
The 1977 ENMOD Convention is the primary international instrument of direct rele-
vance to weather modification.
93
It prohibits state parties from ‘engag[ing] in military
or any other hostile use of environmental modification techniques having widespread,
long-lasting or severe effects as the means of destruction, damage or injury to any other
State Party’.
94
China acceded to the Convention in 2005.
95
However, the treaty estab-
lishes obligations concerning weather modification only for military or hostile pur-
poses, while encouraging the use of weather modification for peaceful purposes,
such as water management.
96
Article III(2) of the ENMOD Convention provides:
‘The States Parties to this Convention undertake to facilitate, and have the right to par-
ticipate in, the fullest possible exchange of scientific and technological information on
the use of environmental modification techniques for peaceful purposes’.
97
Apart from
a broad commitment to facilitate exchange of scientific and technological information,
the ENMOD Convention does not impose legal limits on China’s use of weather modi-
fication for peaceful purposes.
Community Confronts “Rogue Science”’,The Wire Science, 19 Dec. 2018, available at: https://science.
thewire.in/external-affairs/world/chinas-scientific-community-confronts-rogue-science.
91
Flossmann et al., n. 9 above, p. 78.
92
New York, NY (US), 10 Dec. 1976, in force 5 Oct. 1978, available at: https://treaties.un.org/doc/Treaties/
1978/10/19781005%2000-39%20AM/Ch_XXVI_01p.pdf.
93
Ibid., Art. I.
94
Ibid., Art. I(1).
95
See, e.g., United Nations Treaty Collection, available at: https://treaties.un.org/Pages/ViewDetails.aspx?
src=TREATY&mtdsg_no=XXVI-1&chapter=26&clang=_en.
96
ENMOD Convention, n. 92 above, Art. III(1). For a detailed analysis see J. McGee et al., ‘International
Governance of Solar Radiation Management: Does the ENMOD Convention Deserve a Closer Look?’
(2020) 14(4) Carbon & Climate Law Review, pp. 294–305, pp 297–9.
97
ENMOD Convention, n. 92 above, Art III(2).
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For the Convention to apply, the hostile intent of a state needs to be demonstrated.
While the term ‘hostile’is not defined in the text or in the travaux préparatoires, the
context in which the Convention was negotiated is crucial for understanding its
scope. The ENMOD Convention originated with the 1974 Conference of the
Committee on Disarmament.
98
The Preamble states that state parties were guided by
‘the cause of halting the arms race, and of bringing about general and complete dis-
armament under strict and effective international control, and of saving mankind
from the danger of using new means of warfare’.
99
As confirmed during the first review
conference, the ENMOD Convention is a multilateral disarmament convention,
intended to prevent the development and use of technology for environmental –
including meteorological –warfare.
100
It was not intended as an environmental agree-
ment to manage (transboundary) environmental impacts. Initially intended to apply to
situations of armed conflict, Bodle argues that ‘[a]pplying the ENMOD Convention in
peacetime on the basis of a subjectively determined “hostile”use would erode this dis-
tinction and introduce a grey area between the two areas of law’.
101
It is important,
therefore, to distinguish between risks of transboundary harm from weather modifica-
tion and the hostile use of these technologies. Conflating the two does not accurately
reflect the scope and purpose of this Convention, and there is no state practice or
decision of international courts or tribunals to support such an interpretation.
We acknowledge concerns regarding the potential future militarization of the
Chinese weather modification programme. However, as long as China continues to
conduct its weather modification programme for peaceful purposes, it does so in com-
pliance with the ENMOD Convention. While the provisions of this Convention may
become relevant in future, China’s present execution of its weather modification
programme falls outside the scope of the Convention.
3.2. The No-Harm Rule
The ‘no-harm rule’is a fundamental principle of customary international environmen-
tal law. Originating from the Trail Smelter arbitration (1938–1941),
102
the no-harm
rule imposes a due diligence obligation on states to prevent activities within their juris-
diction and control that cause significant transboundary harm to the territory of other
states and areas beyond national jurisdiction.
103
The no-harm rule has been affirmed in
98
UN General Assembly, ‘Report of the Conference of the Committee on Disarmament’, 1976, UN Doc.
A/31/27.
99
ENMOD Convention, n. 92 above, Preamble.
100
‘Final Document of the First Review Conference of the Parties to the Convention on the Prohibition of
Military or Any Other Hostile Use of Environmental Modification Techniques’(1984), ENMOD/
CONF.1/13/1, available at: https://s3.amazonaws.com/unoda-web/documents/library/conf/ENMOD-
CONF-1-13-1.PDF.
101
R. Bodle, ‘Geoengineering and International Law: The Search for Common Legal Ground’(2013) 46
Tulsa Law Review, pp. 305–22, at 312.
102
Trail Smelter (United States v. Canada), Awards, 16 Apr. 1938 and 11 Mar. 1941, Reports of
International Arbitral Awards, Vol. III, pp. 1905–82, at 1965.
103
The ICJ has affirmed that the no-harm rule applies also to areas beyond national jurisdiction in Legality of
the Threat or Use of Nuclear Weapons, Advisory Opinion, 8 July 1996, ICJ Reports (1996), pp. 226–67,
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multiple decisions by international courts and tribunals.
104
It has also been
re-articulated in Principle 21 of the Stockholm Declaration,
105
Principle 2 of the Rio
Declaration,
106
and in numerous multilateral environmental agreements.
107
As a prin-
ciple of customary international law, the no-harm rule is legally binding on all states
and can be enforced through international litigation. Examples of situations in
which states have invoked this rule include transboundary air pollution from smelt-
ers
108
and aerial herbicide spraying,
109
pollution of shared waterways,
110
and the
alteration of river flows.
111
The no-harm rule imposes substantive and procedural obligations on states for activ-
ities that pose a risk of ‘significant’transboundary harm.
112
There is no objective def-
inition of this threshold,
113
but the International Law Commission (ILC) suggests that
‘significant’means ‘something more than “detectable”but need not be at the level of
“serious”or “substantial”’.
114
As noted above, there is concern that China’s weather
modification activities could cause severe weather conditions hundreds of kilometres
beyond the target area, and may either deprive neighbouring states of rainfall or
cause flooding. Such risks are not trivial and would be likely to satisfy the
Commission’s threshold.
The no-harm rule is generally interpreted as providing states with a substantive ‘due
diligence’obligation, in that states must use ‘all means at their disposal’to avoid
significant transboundary harm occurring, but are not required to prevent it
at 241–2. The ICJ affirmed the due diligence nature of this obligation in Pulp Mills on the River Uruguay
(Argentina v. Uruguay), Judgment, 20 Apr. 2010, ICJ Reports (2010), pp. 14–107, at 55–6.
104
See, e.g., Corfu Channel (United Kingdom v. Albania), Merits, 9 Apr. 1949, ICJ Reports (1949), pp. 4–
169, at 22; Lake Lanoux Arbitration (France v. Spain), Award, 16 Nov. 1957, 24 International Law
Reports (1957), pp. 101–42, at 129; Gabc
ikovo/Nagymaros Project (Hungary v. Slovakia), Judgment,
25 Sept. 1997, ICJ Reports (1997), pp. 7–84, at 41.
105
Declaration of the UN Conference on the Human Environment, adopted by the UN Conference on the
Human Environment, Stockholm (Sweden), 5–16 June 1972, UN Doc. A/CONF/48/14/Rev.1, available
at: http://www.un-documents.net/aconf48-14r1.pdf.
106
Rio Declaration, n. 28 above.
107
See, e.g., United Nations Convention on the Law of the Sea (UNCLOS), Montego Bay (Jamaica), 10 Dec.
1982, in force 16 Nov. 1994, Arts 192–194(2), available at: https://www.un.org/depts/los/
convention_agreements/texts/unclos/unclos_e.pdf; Convention on Biological Diversity, Rio de Janeiro
(Brazil), 5 June 1992, in force 29 Dec. 1993, Art. 3, available at: https://www.cbd.int/doc/legal/cbd-en.
pdf; United Nations Framework Convention on Climate Change, Rio de Janeiro (Brazil), 9 May 1992,
in force 21 Mar. 1994, Preamble, available at: https://unfccc.int/resource/docs/convkp/conveng.pdf;
Vienna Convention for the Protection of the Ozone Layer, Vienna (Austria), 22 Mar. 1985, in force
22 Sept. 1988, preamble, available at: https://ozone.unep.org/treaties/vienna-convention.
108
Trail Smelter, n. 102 above.
109
See, e.g., Case concerning Aerial Herbicide Spraying (Ecuador v. Colombia), Memorial of Ecuador Vol. I,
28 Apr. 2009, ICJ General List No. 138, p. 273 (Aerial Herbicide Spraying).
110
Pulp Mills, n. 103 above.
111
Lake Lanoux, n. 104 above.
112
For a detailed discussion, see K.A. Brent, ‘The Certain Activities Case: What Implications for the
No-Harm Rule?’(2017) 20(1) Asia Pacific Journal of Environmental Law, pp. 28–56.
113
Ibid., p. 53.
114
International Law Commission (ILC), ‘Draft Articles on Prevention of Transboundary Harm from
Hazardous Activities, with Commentaries’(2001) vol II, Part 2, Yearbook of the International Law
Commission, pp. 148–70, at 152.
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absolutely.
115
The standard of care required to discharge this obligation depends on the
activity in question. The care must be ‘appropriate and proportional to the degree of
risk of transboundary harm’,
116
with riskier activities attracting a higher standard of
care. There are no international law cases involving weather modification that specify
the type of action that is necessary, but the International Court of Justice (ICJ) has
noted that risks of environmental harm are often irreversible and therefore warrant a
more stringent standard of care.
117
The ILC Draft Articles on Prevention of
Transboundary Harm also suggest that the size and location of an activity, special cli-
mate conditions, and materials used should also be considered in determining the
standard of care.
118
The size of China’s weather modification programme and its prox-
imity to national borders would probably justify a high standard of care. The submis-
sion by Colombia in the Aerial Spraying judgment provides examples of the types of
action that might be required, such as ensuring the use of the most up-to-date technol-
ogy and methods, ensuring environmental monitoring, ongoing scientific review of the
programme, and independent auditing of the programme.
119
To satisfy their due diligence obligation under the no-harm rule, states must also take
appropriate regulatory and administrative action to address the risk of transboundary
harm.
120
The ICJ made clear in its 2010 Pulp Mills judgment that this entails the adop-
tion and vigilant enforcement of appropriate rules and measures under domestic
law.
121
Those rules should adopt or give effect to a precautionary approach, in that
states cannot use scientific uncertainty regarding the precise nature of risks as an excuse
to ignore their obligations under customary international law.
122
Adopting a precau-
tionary approach is especially relevant for activities like weather modification, where
there might be ‘plausible indications’of potential transboundary risks but uncertainty
concerning their scope or nature.
123
In such situations, Boyle suggests that the precau-
tionary approach may indeed ‘reduce the standard of proof required in order to
115
Pulp Mills, n. 103 above, pp. 55–6; see also ILC, ibid., pp. 153–5; B. Mayer, ‘Obligations of Conduct in
the International Law on Climate Change: A Defence’(2018) 27(2) Review of European, Comparative &
International Environmental Law, pp. 130–40, at 133–4; A. Boyle, ‘Transboundary Air Pollution: A Tale
of Two Paradigms’, in S. Jayakumar et al. (eds), Transboundary Pollution: Evolving Issues of
International Law and Policy (Edward Elgar, 2015), pp. 233–60, at 237.
116
Responsibilities and Obligations of States with respect to Activities in the Area, Advisory Opinion,
International Tribunal for the Law of the Sea (ITLOS), Case No. 17, 1 Feb. 2011, pp. 14–78, at 43
(Activities in the Area). While this case involved rules under UNCLOS (n. 107 above), the comments
of ITLOS on the nature of due diligence obligations apply also to customary international law.
117
Pulp Mills, n. 103 above, pp. 76–7; Gabc
ikovo/Nagymaros Project, n. 104 above, p. 77. See also
K. Schmalenbach, ‘States Responsibly and Liability for Transboundary Environmental Harm’,in
P. Gailhofer et al. (eds), Corporate Liability for Transboundary Environmental Harm:
An International and Transnational Perspective (Springer, 2023), pp. 43–84, at 57.
118
ILC, n. 114 above, p. 154.
119
Aerial Herbicide Spraying, n. 109 above, pp. 376–7.
120
Pulp Mills, n. 103 above, p. 79; South China Sea Arbitration (Philippines v. China), Awards, 12 July
2016, Permanent Court of Arbitration, Case No. 2013-9, pp. 375–6; ILC, n. 114 above, p. 154.
121
Pulp Mills, n. 103 above, p. 79.
122
Activities in the Area, n. 116 above, pp. 46–7. See also Boyle, n. 115 above, pp. 243–5.
123
Activities in the Area, n. 116 above, p. 46.
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establish that an activity poses a risk of harm’.
124
In other words, the precautionary
principle implies that states still have obligations under the no-harm rule where there
is a risk of serious or irreversible transboundary harm, but there is uncertainty as to
its precise nature or magnitude.
If triggered, the no-harm rule also imposes procedural obligations on states: namely,
the duty to conduct a transboundary environmental impact assessment (EIA),
125
the
duty to cooperate, and a duty to notify and consult with potentially affected states.
126
In its Pulp Mills judgment, the ICJ affirmed the duty to conduct a transboundary EIA as
a principle of customary international law in its own right, as well as a necessary
component of due diligence.
127
Customary international law does not dictate the
precise content and scope of a transboundary EIA, but the ICJ has noted that it should
reflect the ‘nature and magnitude of the proposed development and its likely adverse
impact on the environment’.
128
Several international organizations have recommended that states conduct weather
modification activities in line with the no-harm rule and have further clarified what
states should do to satisfy their international legal obligations. In 1980, the United
Nations Environmental Programme (UNEP) developed the Provisions on the
Cooperation of States in Weather Modification.
129
These provisions explicitly extend
general principles of international law, including the no-harm rule, to weather modifi-
cation activities, stating that ‘weather modification activities should be conducted in a
manner designed to ensure that they do not cause damage to the environment of other
States or of areas beyond the limits of national jurisdiction’.
130
They recommend that
states assess the environmental consequences of weather modification activities ‘which
are likely to have an effect on areas outside of their national jurisdiction’and ‘make the
results of such assessments available to all concerned States’.
131
They also recognize
that states have obligations of cooperation, consultation, notification and exchange
of information concerning weather modification activities that present transboundary
risks.
132
The UNEP Provisions recommend that states gather and record information
on weather modification to make it available to the WMO,
133
and invite states to
‘encourage and facilitate international cooperation’through bilateral, regional or
multilateral agreements.
134
124
Boyle, n. 115 above, pp. 244.
125
Activities in the Area, n. 116 above, pp. 64–5.
126
Certain Activities Carried Out by Nicaragua in the Border Area (Costa Rica v. Nicaragua) and
Construction of a Road in Costa Rica along the San Juan River (Nicaragua v. Costa Rica), Judgment,
16 Dec. 2015, ICJ Reports (2015), pp. 6–81, at 45 (Nicaragua/Costa Rica).
127
Activities in the Area, n. 116 above, p. 72.
128
Pulp Mills, n. 103 above, p. 73.
129
UNEP Governing Council, ‘Provisions for Co-operation between States in Weather Modification’,
29 Apr. 1980, Decision 8/7/A.
130
Ibid., para. 1(f ).
131
Ibid., para. 1(e).
132
Ibid., para. 1(b)–(d).
133
Ibid., para. 1(c).
134
Ibid., para. 1(h).
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In 2018, the ILC finalized its Draft Guidelines on the Protection of the Atmosphere,
which provide that ‘intentional large-scale modification of the atmosphere should be
conducted with prudence and caution, subject to any applicable rules of international
law’.
135
This further suggests that states should comply with the no-harm rule when
conducting large-scale weather modification activities. Therefore, to satisfy its obliga-
tions, China would need to conduct transboundary EIAs of weather modification activ-
ities, as well as notify and consult with neighbouring states that may be adversely
affected by these activities.
4.
This section examines the domestic legal regime governing weather modification in
China. An understanding of this framework is necessary to evaluate China’s
compliance with international customary law, particularly the obligation to prevent
transboundary harm (further discussed in Section 5).
4.1. Institutional Arrangements
China’s current framework focuses on the beneficial impacts of weather modification
for local communities and ecosystems. The Meteorology Law 1999 lays the legal foun-
dation for Chinese weather modification projects and policies in its Chapter V
‘Prevention of Meteorological Disasters’.
136
The law defines weather modification as:
efforts aimed at rain or snow enhancement, hail suppression, rain suppression, fog disper-
sal, frost prevention by exerting, under appropriate conditions, artificial influence on local
atmospheric, physical and chemical processes through scientific and technological means,
in order to avert or mitigate meteorological disasters and rationally exploit climatic
resources.
137
This definition extends beyond the mere avoidance of weather disasters to the exploit-
ation of climatic resources. The Regulations on Meteorological Services 1994, which
the Meteorology Law replaced, defined climatic resources as ‘climate conditions such
as solar, thermal, hydraulic and wind energy which can be used in human economic
activities’.
138
However, the current Meteorology Law does not define ‘climatic
resources’. While the reasons behind this omission are unclear, Chen and Cui explain
that ‘[o]ne reason might have been to preserve the flexibility to expand the scope of the
definition whenever technological advances facilitate the exploitation of new forms of
climate resources’, including the exploitation of atmospheric water via weather
135
ILC, ‘Draft Guidelines on the Protection of the Atmosphere, with Commentaries’(2021) Vol II, Part 2,
Yearbook of the International Law Commission, pp. 13–51, at 31.
136
Meteorology Law of the People’s Republic of China, 31 Oct.1999, in force 1 Jan. 2000, available at:
http://www.china.org.cn/environment/2007-08/27/content_1034467.htm (official English translation).
137
Ibid., Art. 41(5).
138
Regulations on Meteorological Services, issued by the State Council, 18 Aug. 1994, ineffective 1 Jan.
2000 (in Chinese) (cited in Chen & Cui, n. 76 above, pp. 87–8).
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modification.
139
The lack of definition may give the law a wider scope, but it also
creates uncertainty regarding the type of activity to which the Law might apply.
Under Article 30 of the Meteorology Law, governments at all levels are authorized to
plan and organize weather modification.
140
It also provides competent meteorological
departments with authority to administer, guide and arrange weather modification
operations.
141
At the national level, the CMA Department of Emergency Response,
Disaster Mitigation and Public Services coordinates weather modification activities,
supervises the workof local meteorological departments, and organizes research through
nine meteorological institutes.
142
Article 30 also outlines the obligations that bodies
engaging inweather modification activities must satisfy: these include having appropriate
qualifications, using specified equipment, and following any operational rules.
143
Under
Article 39,violations of Article 30requirements incur sanctions ranging from injunctions
and disciplinary warnings to fines of up to CN¥100,000 (or about US$ 20,000).
144
Compensation is payable if weather modification conducted in breach of
Article 30 causes loss to others.
145
However, the Law does not create compensation
mechanisms for loss caused by weather modification activities conducted in compliance
with Article 30. It is also unclear whether such compensation could be paid to foreign
nationals –or neighbouring countries –adversely affected by the activities.
The State Council adopted the Regulations on Administration of Weather
Modification in 2002 ‘for the purpose of strengthening the administration of weather
modification, and preparing against and mitigating meteorological disasters’.
146
The
regulations recognize that weather modification plans prepared by local meteorological
departments and approved by governments are for ‘public welfare’and expenses
included in governments’budgets.
147
Under the regulations, local governments are
responsible for organizing experts to evaluate the effects of weather modification.
148
The regulations also require the exchange of information between relevant
departments, including meteorological stations and departments in charge of
agriculture, water conservancy, and forestry.
149
However, nothing in the law or the
139
Ibid.
140
Meteorology Law, n. 136 above, Art. 30.
141
Ibid.
142
‘Meteorological bureaus are established in 31 provinces, autonomous regions and municipalities (exclud-
ing meteorological services at Hong Kong, Macao, and Taiwan), 14 meteorological bureaus at
sub-provincial cities (including 4 cities which have been specifically designated in the state development
plan), 318 meteorological bureaus at prefecture level and 2,300 bureaus (stations) at county level’:‘China
Meteorological Administration’,China Meteorological News Press, 31 July 2008, available at:
http://www.cma.gov.cn/en/aboutcma/introduction/201203/t20120319_166488.html.
143
Meteorology Law, n. 136 above, Art. 30.
144
Ibid., Art. 39. The authors are unaware of any sanction given under Art. 39.
145
Ibid.
146
Regulations on Administration of Weather Modification, issued by the State Council, 19 Mar. 2002, in
force 1 May 2002, Art. 1, available at: https://faolex.fao.org/docs/pdf/chn137408E.pdf (official English
translation).
147
Ibid., Art. 5.
148
Ibid., Art. 7.
149
Ibid., Art. 13.
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regulations provides for exchange of information with foreign counterparts regarding
activities conducted in the proximity of international borders.
Most responsibilities lie with the meteorological departments. The meteorological
departments of provinces, autonomous regions, or municipalities (that is, at the
subnational level) have the authority to determine the most suitable sites for weather
modification operations,
150
define qualification requirements,
151
and organize training
and examination of personnel engaged in weather modification.
152
As at 2014, close to
48,000 people were employed in weather modification activities
153
and thus required
training under the regulations.
154
In addition, the meteorological departments at or
above county (local) levels are responsible for ensuring the safety of operations, includ-
ing through public notification of weather modification operations.
155
As Gasser
explains:
The national, regional and provincial levels are mainly responsible for the implementation
of weather modification projects involving aircraft operations, the city, county and station
level on the other hand, are responsible for the execution of ground operations with rockets
and cannons.
156
Regional Weather Modification Centres coordinate weather modification at the
regional level.
157
The CMA established the Weather Modification Centre in 2007,
158
but it was only officially launched by the Communist Party’s Central Committee and
the State Council in 2021.
159
The CMAWeather Modification Centre coordinates wea-
ther modification operations across the six weather modification regions (for example,
cross-regional operations) and participates in the development of national weather
modification plans and guidelines.
160
For instance, the Weather Modification Centre
has developed a system of real-time communication –the National Air-Ground
Communication System –which allows for the rapid exchange of information in air-
based weather modification operations.
161
Despite these technological advances,
150
Ibid., Art. 8.
151
Ibid., Art. 9.
152
Ibid., Art. 10.
153
2014–20 WMDP, n. 64 above, para. I(1).
154
See, e.g., Regulations, n. 146 above, Art. 12.
155
‘Where weather modification operations are to be implemented, the local competent meteorological
department shall, on the basis of the actual situations, make a public announcement in advance and notify
the local public security organ to ensure safety and security’: ibid.
156
Gasser, n. 81 above, p. 37.
157
2014–20 WMDP, n. 64 above, para. V(1)(1).
158
CMA, ‘60-Years Weather Modification in China’, 13 Sept. 2018, available at: http://www.cma.gov.cn/
en2014/news/Features/201809/t20180913_477849.html.
159
See also, CMA, ‘China Meteorological Administration Weather Modification Center Officially
Launched’, 2021, available at: http://www.cma.gov.cn/2011xwzx/2011xqxxw/2011xqxyw/202112/
t20211221_589354.html (in Chinese).
160
2021–25 WMDP, n. 45 above, para. IV(5)(2). See also CMA, ‘Weather Modification Center of China
Meteorological Administration’, available at: http://www.cma.gov.cn/zfxxgk/gknr/jgyzn/jgsz/zsdw/
202008/t20200805_4629772.html (in Chinese).
161
See generally D. Li et al., ‘FACT: An Air-Ground Communication Framework for Seeding Quality
Control of Aircraft’(2022) 41(2) Computer Systems Science and Engineering, pp. 539–55.
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information on weather modification activities is not systematically made accessible to
other states or the WMO.
The regulations also stipulate safety standards for equipment. They require that wea-
ther modification equipment, including rockets and rocket launchers, be manufactured
according to national technical standards and requirements.
162
These materials must
be transported and stored in accordance with laws related to the administration of
weaponry and explosives,
163
and must be verified annually.
164
It is an offence to use
equipment that fails to meet these safety standards,
165
and individuals and organiza-
tions responsible for causing serious accidents in violation of the regulations may be
held civilly or criminally liable.
166
Despite this extensive framework governing the administrative and safety aspects of
weather modification, the regulations do not provide for impact assessment of weather
modification operations. Instead, this falls within the scope of China’s general environ-
mental legislation.
4.2. Environmental Impact Assessment of Weather Modification
The Law on Environmental Impact Assessment of the People’s Republic of China 2002
(EIA Law) (amended in 2016 and 2018) requires relevant departments at all levels to
prepare EIAs for both plans and construction projects.
167
While ‘plans’and
‘construction projects’are not defined, weather modification activities fall within the
scope of the EIA Law in so far as they require the construction of delivery apparatus,
such as installation of ground generators. The 2014–20 WMDP required EIAs for
specific weather modification projects (‘construction projects’), in recognition that
increased rainfall would ‘provide ecological water for larger areas through natural
water system and water conservancy facilities’but would also ‘directly affect local
ecosystems’.
168
No separate EIA was needed for the Weather Modification Develop-
ment Plans, as Article 18 of the EIA Law prevents the duplication of EIA requirements.
169
All construction projects must undergo some form of assessment, but different
requirements apply depending on the likelihood of a project causing significant
impacts.
170
Article 16 of the EIA Law provides that ‘[i]f the environmental impacts
may be significant, [the construction entities] shall work out a report of environmental
impacts so as to include an all-round appraisal of the environmental
162
Regulations, n. 146 above, Art. 15.
163
Ibid., Art. 16.
164
Ibid., Art. 17.
165
Ibid., Art. 18.
166
Ibid., Arts 19, 20.
167
Law on Environmental Impact Assessment of the People’s Republic of China, 28 Oct. 2002, amended
29 Dec. 2018 (EIA Law), available at: https://english.mee.gov.cn/Resources/laws/environmental_laws/
202012/t20201204_811509.shtml (official English translation), and https://www.commissiemer.nl/
docs/os/sea/legislation/china_s_ea_legislation_03.pdf (unofficial English translation).
168
2014–20 WMDP, n. 64 above, para. I(2).
169
EIA Law, n. 167 above, Art. 18.
170
X. He, ‘In the Name of Legitimacy and Efficiency: Evaluating China’s Legal Reform on EIA’(2020) 32(3)
Journal of Environmental Law, pp. 441–69, at 450.
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impacts’.
171
Accordingly, the competent meteorological bureau in each of China’s six
weather modification regions was required to prepare comprehensive environmental
impact statements (EIS) for their weather modification construction projects. The EIS
must contain an environmental baseline study, an evaluation of the potential environ-
mental impacts and protection measures, a cost-benefit analysis, suggestions for envir-
onmental monitoring, and an overall assessment of whether a project should
proceed.
172
In recent years, China has consolidated its EIA system to remedy deficien-
cies.
173
However, the multiplicity of amendments and technical guidelines has rendered
the system complex, fragmented, and unpredictable. Issues of local government
accountability, enforcement, and public participation remain.
174
The EIA legislation makes access to information and public participation manda-
tory, unless the state deems the project to be confidential.
175
Some regions have already
conducted and published EISs for their weather modification projects.
176
In most cases,
the proponent is required to solicit comments from both experts and the public, and to
specify which comments have been considered when finalizing the EIS.
177
However, the
EIS for the Southwest region, in which the Sky River project is located, is confidential
and not publicly available.
While the Chinese central government has progressively formalized public participa-
tion in environmental decision making,
178
local authorities have been able to select
their preferred participation mechanisms (such as expert meetings or solicitations of
opinion).
179
Some local officials have carried out participation processes
formalistically.
180
Questionnaires are the main method of public participation, rather
than public hearings or meetings. This technique has significant drawbacks.
181
171
EIA Law, n. 167 above, Art. 16.
172
Ibid., Art. 17.
173
Y. Yang, ‘Reformed Environmental Impact Assessment in China: An Evaluation of Its Effectiveness’
(2020) 11(10) Journal of Environmental Protection, pp. 889–908, at 889–90.
174
He, n. 170 above, p. 459.
175
EIA Law, n. 167 above, Art. 21.
176
E.g., the EIA of the Southeastern weather modification project was announced in 2017, available at:
http://gd.cma.gov.cn/zfxxgk/tzgg_91206/202011/t20201102_2334794.html (in Chinese).
177
EIA Law, n. 167 above, Art. 21.
178
See, e.g., State Environmental Protection Administration, ‘Provisional Measures for Public Participation
in Environmental Impact Assessment’(2006), available at: https://www.chinalawtranslate.com/en/
enviroparticipation (unofficial translation); Ministry of Ecology and Environment, ‘Measures for
Public Participation in Environmental Impact Assessment’, 16 Oct. 2018, available at:
https://asiasociety.org/sites/default/files/inline-files/_2018_MEE_Measures%20for%20Public%20Parti
cipation%20in%20Environmental%20Impact%20Assessment_E_0.pdf (unofficial translation). For a
review of participation requirements see, e.g., J. Wu et al., ‘Environmental Impact Assessment’,in
J. Wu & I.S. Chang (eds), Environmental Management in China: Policies and Institutions (Springer,
2020), pp. 35–62, at 49.
179
M. Beach, B. Bleish & S. Yang, ‘The Role of Public Participation in Ecological Impact Assessment (EcIA)
and Environmental Impact Assessment (EIA) in China’(2006) 8 China Environment Series, pp. 3–27, at
4–5.
180
T. Johnson, ‘Public Participation in China’s EIA Process and the Regulation of Environmental Disputes’
(2020) 81 Environmental Impact Assessment Review, pp. 1–7, at 3.
181
J. Wu et al., ‘Strategic Environmental Assessment Implementation in China: Five-Year Review and
Prospects’(2011) 31(1) Environmental Impact Assessment Review, pp. 77–84, at 80.
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Pre-defined questions can be complex, selected participants are not always representa-
tive of affected communities, and the acceptance or rejection of comments is often
poorly justified.
182
Accordingly, commentators have suggested that China’s efforts to
increase participation in EIA has been ineffective in practice.
183
The agency responsible for assessing impacts also varies with the size of the proposed
project. Under the EIA Law, an EIS must be examined and approved by ‘the competent
administrative department in charge of environmental protection’.
184
Reforms have
devolved approval powers to provincial and county-level environmental protection bur-
eaus to streamline EIA procedures and improve efficiency.
185
However, the national
Ministry of Ecology and Environment remains responsible for reviewing and approving
the EIS for construction projects ‘that include different provinces, autonomous regions or
municipalities directly under the Central Government’.
186
This is notably the case for
regional weather modification projects that are cross-boundary in nature.
Nevertheless, the EIA Law does not require consideration of potential transboundary
impacts.
The Chinese EIA framework does not require or provide for participation by the
public located outside China. However, this omission is not unique to the Chinese
context, and unsurprising given that there is no regional framework for cooperation
on EIA in Asia.
187
Boyle suggests that denying equal access to information, participa-
tion, and effective remedies to people affected extraterritorially could amount to a
human rights violation.
188
However, there is no such requirement under international
customary law, which requires ‘state’participation, rather than public participation.
189
The Northwestern region is the largest weather modification region, covering an
area of about 3.53 million km
2
.
190
Its EIS was the first to be published in 2016,
191
pro-
viding insights into some of the limitations of EIA approaches in the context of weather
182
X. Yao, J. He & C. Bao, ‘Public Participation Modes in China’s Environmental Impact Assessment
Process: An Analytical Framework Based on Participation Extent and Conflict Level’(2020) 84
Environmental Impact Assessment Review, pp. 1–12, at 8.
183
D. Brombal, A. Moriggi & A. Marcomini, ‘Evaluating Public Participation in Chinese EIA: An Integrated
Public Participation Index and Its Application to the Case of the New Beijing Airport’(2017) 62
Environmental Impact Assessment Review, pp. 49–60, at 58–9; J. Wu et al., ‘Study on the Practice of
Public Participation in Environmental Impact Assessment by Environmental Non-Governmental
Organizations in China’(2017) 74(C) Renewable and Sustainable Energy Reviews, pp. 186–200, at 195–6.
184
EIA Law, n. 167 above, Art. 22.
185
He, n. 170 above, pp. 447–9.
186
EIA Law, n. 167 above, Art. 23.
187
A. Ogihara, M. Shimaoka & H. Roppongi, ‘Potentialities for a Regional Public Participation Framework
in Asia: An Environmental Assessment Perspective’(2016) 52 Land Use Policy, pp. 535–42, at 535.
188
Boyle, n. 115 above, pp. 252–3.
189
S. Marsden, ‘Public Participation in Transboundary Environmental Impact Assessment: Closing the Gap
between International and Public Law?’, in B. Jessup & K. Rubenstein (eds), Environmental Discourses in
Public and International Law (Cambridge University Press 2012), pp. 238–60, at 246.
190
2014–20 WMDP, n. 64 above, para. III(2)(2).
191
The Northwestern region comprises the provinces of Gansu, Shaanxi, Qinghai, Ningxia, Xinjiang, and
four cities of Inner Mongolia (Alxa League, Bayannaoer City, Wuhai City, Ordos City): Beijing
Municipal Research Institute of Environmental Protection & Chinese Academy of Meteorological
Sciences, ‘Environmental Impact Report of Construction Projects for Weather Modification in
Northwest China’, 2016 (Northwestern EIA), available at: https://www.mee.gov.cn/ywgz/hjyxpj/
Manon Simon, Jan McDonald and Kerryn Brent 21
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modification. The Northwestern EIS considered pollution resulting from the
construction phase of the project (2016–2019), focusing on dust, noise, water
pollution, and solid waste.
192
It concluded that these would not have significant
environmental impacts after appropriate mitigation actions.
193
The EIS also addressed
the environmental impacts of the weather modification operations themselves,
194
stating that operations were expected to use 208 kilograms of silver iodide each
year.
195
The assessors noted the low toxicity of silver iodide and concluded that the
operations would not have significant environmental impact because the potential
concentrations were far below the National Standard for Drinking Water Health
Standards (≤0.05 mg/L (milligrams per litre)).
196
However, the EIS did not consider
the overall amount of silver iodide used countrywide because EIA procedures in
China (as in many countries) focus on the direct impacts of a proposed activity, and
do not require consideration of indirect or cumulative impacts and interactions.
197
The Northwestern EIS completed two stages of public participation. Following
online publicity and onsite public notices, the CMA solicited public opinion through
a questionnaire (rather than a public hearing). According to the EIS, 96.8% of those
contacted responded to the questionnaire.
198
No one expressed opposition to the pro-
posed project,
199
although 62.8% of participants responded that they had only a slight
understanding of weather modification.
200
This experience reflects a limitation of the
EIS process in China: that participation procedures can be (and often are) designed
to comply with minimum legal requirements, rather than facilitate meaningful public
consultation.
201
Indeed, ‘top-down’participation mechanisms, such as questionnaires,
are often conducted after decisions are reached, casting serious doubt on their influence
in decision making.
202
This approach to EIA is also consistent with what has been
referred to as ‘authoritarian environmentalism’, where ‘[p]ublic participation is limited
to a narrow cadre of scientific and technocratic elites while others are expected to par-
ticipate only in state-led mobilisation for the purposes of implementation’.
203
jsxmhjyxpj/xmslqk/201609/W020160909514890214465.pdf (translated by the authors from Chinese
to English).
192
Ibid., para. 4(3).
193
Ibid., para. 13(1).
194
Ibid., para. 4(4).
195
Ibid., para. 3(4)(3).
196
Ibid., para. 8(4).
197
Y. Wang, R.K. Morgan & M. Cashmore, ‘Environmental Impact Assessment of Projects in the People’s
Republic of China: New Law, Old Problems’(2003) 23(5) Environmental Impact Assessment Review,
pp. 543–79, at 558–9.
198
Northwestern EIA, n. 191 above, para. 17(8).
199
Ibid.
200
Ibid., para. 17(6)(2)(2).
201
C.S.F. Chi, J. Xu & L. Xue, ‘Public Participation in Environmental Impact Assessment for Public Projects:
A Case of Non-Participation’(2014) 57(9) Journal of Environmental Planning and Management,
pp. 1422–40, at 1424.
202
Johnson, n. 180 above, p. 1.
203
B. Gilley, ‘Authoritarian Environmentalism and China’s Response to Climate Change’(2012) 21(2)
Environmental Politics, pp. 287–307, at 288.
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The Northwestern EIS acknowledged that rain enhancement operations would have
impacts on surface water but concluded that the impacts on nearby nature reserves
would be positive.
204
These nature reserves constitute natural habitat for species
protected under the Convention on International Trade in Endangered Species of Wild
Fauna and Flora (CITES)
205
and bilateral agreements on migratory birds;
206
thus, sup-
porting the ecological health of these areas is consistent with international obligations.
The Northwestern EIS did address the issue of potential extra-area effects. It recog-
nized that weather modification would be likely to increase overall precipitation over
non-target areas by 1%, equivalent to approximately 60 billion tons of water, without
changing its temporal and spatial distribution.
207
Concerning the risks of impacts
beyond China’s borders, the EIS explained that, because weather systems essentially
move from west to east across China, the expected increase in rainfall would mostly
affect the Chinese territory.
208
The Northwestern EIA process did not require or
include any consultation or cooperation with adjacent countries, nor with countries
along the Mekong-Lancang river, which originates in the Northwest region (Qinghai).
To comply with due diligence obligations, China’s EIA processes need to incorporate a
more thorough consideration of transboundary impacts, including through enhanced
transparency and granting neighbouring countries access to relevant information.
The lack of transboundary EIA requirements and consultation with potentially
affected states under Chinese domestic law is concerning, given the scale of current wea-
ther modification projects and their proximity to neighbouring states. Moreover, this
gap has not been filled by any ‘extraordinary’processes of consultation with neigh-
bours, such as India. This raises questions about China’s compliance with its due
diligence obligations under customary international law.
4.3. Ownership of Atmospheric Resources
China has developed a robust legal framework to govern the safety aspects of weather
modification, but questions remain about its ability to address the governance and
ownership of atmospheric water. Under the Constitution, the central government
owns natural resources, including water resources.
209
China’s Water Law 2002
204
Northwestern EIA, n. 191 above, para. 5(4)(2)(2).
205
Washington, DC (US), 3 Mar. 1973, in force 7 Jan. 1975, available at: http://www.cites.org/eng/disc/text.
php.
206
See, e.g., Agreement between the Government of Japan and the Government of the People’s Republic of
China on Protection of Migratory Birds and Natural Habitats Thereof, Beijing (China), 3 Mar. 1981, in
force 8 June 1981, available at: http://extwprlegs1.fao.org/docs/pdf/bi-140191.pdf (in Chinese);
Agreement between the Government of Australia and the Government of the People’s Republic of
China for the Protection of Migratory Birds and their Environment, Canberra (Australia), 20 Oct.
1986, in force 1 Sept. 1988, available at: http://www.austlii.edu.au/au/other/dfat/treaties/ATS/1988/22.
html.
207
Northwestern EIA, n. 191 above, para. 8(3)(3).
208
Ibid.
209
‘All mineral resources, waters, forests, mountains, grasslands, unreclaimed land, beaches and other nat-
ural resources are owned by the state’: Constitutionof the People’s Republic of China, 4 Dec. 1982, Art. 9,
available at: http://www.npc.gov.cn/zgrdw/englishnpc/Constitution/node_2825.htm (official English
translation).
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confirms that ‘water resources are owned by the State’,
210
but the Water Law explicitly
applies to surface water and groundwater and does not clarify the legal status of atmos-
pheric water. The Meteorology Law delegates the management of climatic resources,
including atmospheric water, to lower levels of government.
211
In line with the Meteorology Law, several provinces have asserted state ownership
of climatic resources. In 2012, the Northeastern province of Heilongjiang became the
first to pass Regulations on Climate Resources Survey and Protection, recognizing
state ownership over climatic resources.
212
The regulations define climatic resources
as ‘wind energy, solar energy, precipitation and any component of the atmosphere
that is capable of being used by human activities’.
213
Shanxi, Guangxi, Guizhou,
and Tibet have all passed similar regulations.
214
While several Chinese commentators
have criticized the constitutionality of these provincial regulations, Chen and Cui
argue that the nationalization of climatic resources is consistent with Chinese
law.
215
Chen also argues that, even though state property is often used as a means
to expand governmental control over resources, it is also an optimal property regime
for emerging natural resources, such as atmospheric water.
216
It facilitates future
transition in utilization patterns and creates room for flexibility in the face of scientific
uncertainty.
217
Chien, Hong and Lin suggest a tension between the provisions of the Water Law and
the Meteorology Law which could result in jurisdictional conflicts between the central
and local governments.
218
They argue that the ownership of water resulting from wea-
ther modification activities in the Henan and Hubei provinces, which affect catchment
areas that supply the Greater Beijing region, is uncertain.
219
It is unclear whether these
provinces exclusively own the water or if they are under an obligation to share with cit-
ies in other provinces, including Beijing. The Regulations onAdministration of Weather
Modification 2002 contain provisions intended to avoid disputes between local govern-
ments over so-called ‘cloud theft’. They establish specific procedures for weather modi-
fication operations implemented across the boundaries of provinces, autonomous
regions or municipalities, requiring relevant governments to consult with neighbouring
areas over cross-boundary decision making.
220
Where governments cannot agree, the
210
Water Law of the People’s Republic of China, 21 Jan. 1988, revised 29 Aug. 2002, Art. 3, available at:
http://www.asianlii.org/cn/legis/cen/laws/wlotprocme508 (unofficial English translation).
211
Meteorology Law, n. 136 above, Art. 33.
212
Heilongjiang Province Regulations on Climate Resources Survey and Protection (promulgated by the
Standing Committee of Heilongjiang People’s Congress, 14 June 2012) Art. 7 (cited in Chen & Cui,
n. 76 above, p. 83).
213
Heilongjiang Regulations, Art. 2 (cited in Chen & Ciu, ibid).
214
Chen & Ciu, ibid., p. 89.
215
Ibid., p. 102.
216
J. Chen, ‘Optimal Property Rights for Emerging Natural Resources: A Case Study on Owning
Atmospheric Moisture’(2013) 50(1) University of Michigan Journal of Law Reform, pp. 47–105, at 53.
217
Ibid.
218
Chien, Hong & Lin, n. 23 above, p. 232.
219
Ibid.
220
Regulations, n. 146 above, Art. 14.
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CMA is empowered to decide.
221
However, there are no provisions in the regulations or
elsewhere under Chinese law that require consultation with neighbouring states that
might be affected by China’s weather modification activities.
5.
Concerns over the Chinese weather modification programme are taking place against a
backdrop of diplomatic and military tensions over the disputed Himalayan border,
known as the Line of Actual Control. It extends over 3,500 km between India and
China. The tensions escalated in June 2020, with confrontations in the Galwan valley,
resulting in the loss of military personnel on both sides.
222
These tensions had already
affected hydrological data sharing in 2017. China failed to share data on the
Brahmaputra river following a stand-off in the Doklam region, which compromised
India’s flood control and disaster management capacity.
223
Adding to controversies
relating to China’s construction of dams upstream of transboundary rivers,
224
China’s use of weather modification to control water resources in the Himalayas is chal-
lenging water security in the region.
225
There are also growing concerns over the potential militarization of China’s weather
modification programme.
226
The prospect of weather modification being used for mili-
tary purposes prompted the development of the ENMOD Convention,
227
to which
China is a party. The geopolitical implications of the Chinese weather modification
programme suggest that international mechanisms may be needed to improve state
cooperation and regulate large-scale weather modification. Such an approach was
suggested by the ILC in its report on protection of the atmosphere.
228
221
Ibid.
222
A. Sharma, ‘Galwan Valley Clash Unmasks China’s Geopolitical Intent and India’s Delusion with China’,
The Times of India, 26 Sept. 2020, available at: https://timesofindia.indiatimes.com/blogs/voices/galwan-
valley-clash-unmasks-chinas-geopolitical-intent-and-indias-delusion-with-china.
223
D. Jayaram, ‘Mutual Mistrust Should Give Way to Water Cooperation between India and China’,
Climate Diplomacy, 14 Mar. 2018, available at: https://climate-diplomacy.org/magazine/cooperation/
mutual-mistrust-should-give-way-water-cooperation-between-india-and-china.
224
‘China’s Dam-Building over Brahmaputra Risks Water War with India’,The Economic Times, 24 Jan.
2021, available at: https://economictimes.indiatimes.com/news/defence/chinas-dam-building-over-
brahmaputra-risks-water-war-with-india/articleshow/80432810.cms?from=mdr.
225
A. Roy, ‘“Weather War”: A Latest Addition to the Sino-India Conundrum?’,Observer Research
Foundation, 22 Aug. 2018, available at: https://www.orfonline.org/expert-speak/43534-weather-war-
a-latest-addition-to-the-sino-india-conundrum; J. Griffiths, ‘China to Expand Weather Modification
Program to Cover Area Larger than India’,CNN, 4 Dec. 2020, available at: https://www.cnn.com/
2020/12/03/asia/china-weather-modification-cloud-seeding-intl-hnk/index.html; S. Chaudhary, ‘China
Threatens India with a Weather Modification System that Can Cover 1.5 Times the Area of Entire
India’,The Eurasian Times, 5 Dec. 2020, available at: https://eurasiantimes.com/china-threatens-india-
with-a-weather-modification-system-than-is-1-5-times-larger-than-india.
226
D. Jayaram, ‘Without Attention, Geoengineering Could Upend Foreign Policy’,Wilson Center, 30 Sept.
2020, available at: https://www.wilsoncenter.org/article/without-attention-geoengineering-could-upend-
foreign-policy.
227
ENMOD Convention, n. 92 above.
228
ILC, ‘Third Report on the Protection of the Atmosphere’, 25 Feb. 2016, UN Doc. A/CN.4/692.
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China has contributed actively to international initiatives on meteorological
sciences.
229
This demonstrates a level of commitment to cooperation with the inter-
national scientific community. However, given the large scale of China’s weather modi-
fication activities and the proximity to state borders in which some activities are being
conducted, scientific cooperation alone cannot satisfy China’s obligations under the
no-harm rule.
230
As noted above, China also has an obligation to adopt appropriate
rules and measures at the domestic level to prevent transboundary harm.
231
However, China’s domestic laws for weather modification do not currently fulfil the
procedural obligations required under the no-harm rule relating to impact assessment,
consultation, and notification. Rather than conducting transboundary EIAs, notifica-
tion and consultation on an ad hoc basis, China should develop mechanisms under
its domestic law to ensure routine practice and adherence by weather modification
operators.
If China fails to implement such measures, there are limited options available to
neighbouring states under international law. As noted in Section 3, breaches of the
no-harm rule have been the subject of international litigation, the most recent example
being the Certain Activities and Construction of a Road cases between Costa Rica and
Nicaragua.
232
In order for such a claim to proceed, however, China would need to
consent to have it brought before an international court or tribunal. Alternatively,
neighbouring states in Southeast Asia could seek to negotiate a new regional or
multilateral agreement with China and each other. Such an agreement could facilitate
consultation with countries likely to be affected by weather modification,
233
but the
likelihood of such an agreement seems low. China has been reluctant to join inter-
national agreements regulating the management of transboundary rivers.
234
It has
entered into regional agreements to facilitate transboundary cooperation over shared
water resources with some of its neighbours, such as Russia.
235
However, the practice
of transboundary EIA in China is still in its infancy. At the minimum, setting up an
information-sharing platform could ensure greater transparency in the conduct of
weather modification activities. As Knowles and Skidmore argue, ‘[a]s China invests
substantial funding into programs that are likely to cause ripple effects across multiple
229
CMA, ‘Multilateral Cooperation’, 9 Sept. 2018, available at: http://www.cma.gov.cn/en2014/
international/features/201409/t20140919_261798.html.
230
See Section 3above.
231
Pulp Mills, n. 103 above, p. 69.
232
Nicaragua/Costa Rica, n. 126 above.
233
E.B. Weiss, ‘Principles for International Agreement’(1977) 9(6) Futures, pp. 490–501, at 495.
234
China is not party to the Convention on the Law of the Non-Navigational Uses of International
Watercourses (New York, NY (US), 21 May 1997, in force 17 Aug. 2014, available at: https://legal.un.
org/ilc/texts/instruments/english/conventions/8_3_1997.pdf), nor to the Agreement on the Cooperation
for the Sustainable Development of the Mekong River Basin (Chiang Rai (Thailand), 5 Apr. 1995, available
at: https://www.mrcmekong.org/assets/Publications/policies/agreement-Apr95.pdf).
235
See generally J. Ke & Q. Gao, ‘Only One Mekong: Developing Transboundary EIA Procedures of
Mekong River Basin’(2012) 30(3) Pace Environmental Law Review, pp. 950–1004; N.S. Castillo &
Y. Bian, ‘China’s Obligation to Conduct Transboundary Environmental Impact Assessment (TEIA) in
Utilizing Its Shared Water Resources’(2014) 55(1) Natural Resources Journal, pp. 105–25.
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economies, both transparency and quality analysis are in the interests of the global
community’.
236
Another potential forum for cooperation is the WMO. This organization has long
played a leading role in facilitating information exchange on weather modification
through joint research projects,
237
international training and dialogue,
238
and the cre-
ation of a voluntary reporting mechanism.
239
The WMO terminated its reporting sys-
tem in 2007 and instead established the Expert Team on Weather Modification
Research to keep relevant research under review, provide advice and assistance to states
on scientific experiments, and develop guidelines on the status of weather modifica-
tion.
240
China participates in meetings of the Expert Team, contributes to its trust
fund, and organizes WMO training on weather modification.
241
Until 2001, China
also regularly reported its weather modification activities to the WMO Register on
National Weather Modification Projects. Given the limitations of China’s domestic
arrangements and regional agreements, other states (including states in the region)
could use the WMO forum to formalize cooperation. Re-establishing the voluntary
reporting mechanism is one option, although a mandatory reporting mechanism
would be more effective in avoiding the risk of transboundary effects.
242
6.
A growing number of states are using weather modification as a climate adaptation
measure,
243
but the scale of China’s weather modification programme is unprecedented.
The scale of the Sky River project is significant in its own right, and some critics have
suggested that China’s weather modification programme could provide the infrastruc-
ture needed for more controversial global solar radiation management (SRM), such as
stratospheric aerosol injection.
244
It is currently unlikely that China would deploy SRM
unilaterally,
245
but its weather modification programme does demonstrate the
236
S. Knowles & M. Skidmore, ‘Using Weather Modification to Subdue Severe Weather’, in M. Skidmore
(ed.), Handbook on the Economics of Disasters (Edward Elgar, 2022), pp. 389–99, at 397.
237
See, e.g., P.W. Summers, ‘The WMO Precipitation Enhancement Project (PEP): Progress to Date and
Present Status’(1980) 12(1) The Journal of Weather Modification, pp. 70–83.
238
WMO, ‘WMO Conference on Weather Modification Discusses Research, Environment’,WMO News,
11 Oct. 2011, available at: https://public.wmo.int/en/media/news/wmo-conference-weather-
modification-discusses-research-environment.
239
WMO, ‘Register on National Weather Modification Projects’, available at: https://library.wmo.int/index.
php?lvl=notice_display&id=8188#.YGPTYB1xXUo.
240
World Meteorological Congress & WMO, n. 18 above, p. 54; WMO Strategic Plan, n. 18 above, pp. 49–
50. See also WMO, ‘WWRP Expert Team on Weather Modification’, available at: https://community.
wmo.int/en/activity-areas/wwrp/wwrp-working-groups/wwrp-expert-team-weather-modification.
241
WMO Expert Team on Weather Modification Research, n. 8 above, p. 3.
242
Roslycky, n. 24 above, p. 21.
243
Flossmann et al., n. 9 above, p. 1.
244
ETC Group, n. 65 above.
245
Edney & Symons, n. 74 above, p. 320. See also Z. Liu & Y.Chen, ‘Impacts, Risks, and Governance of
Climate Engineering’(2015) 6(3–4) Advances in Climate Change Research, pp. 197–201, at 200;
W. Weng & Y. Chen, ‘A Chinese Perspective on Solar Geoengineering’, in J.J. Blackstock & S. Low
(eds), Geoengineering Our Climate? Ethics, Politics, and Governance (Routledge, 2018), pp. 155–8.
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country’s willingness and capability to undertake large-scale atmospheric intervention
projects.
246
China is involved in SRM research, but Chinese scientists contend that
China will not proceed with SRM deployment until international collaboration
mechanisms are in place.
247
Weather modification and SRM are often distinguished
on the basis that weather modification is intended to modify weather events at the
local scale, whereas SRM typically contemplates intervention in the climate system at
the global scale.
248
The line is blurred for regional programmes,
249
and the magnitude
of the Chinese weather modification programme raises questions concerning the value
of such distinction.
250
In this article we have argued that China should apply greater
caution in respect of large-scale weather modification.
The Chinese government has developed a strong legal framework to govern the
safety aspects of weather modification, showcasing the government’s purported control
over atmospheric resources. However, the governance of weather modification in
China does not fully address potential environmental impacts associated with the
scale of its programme, especially the risk of transboundary impacts. For China to
comply with international customary law, a revision of its domestic legal framework
is needed to reflect both the substantive and procedural obligations imposed under
the no-harm principle.
Firstly, China should strengthen its legal framework to perform greater ‘due
diligence’in preventing its national weather modification programme from causing
significant transboundary harm, and give effect to a precautionary approach. This is
especially important for projects such as the Sky River project, which take place
close to the boundary with neighbouring states. Secondly, China should adopt and
enforce appropriate procedural measures to address the risk of transboundary harm.
China could create clear processes for conducting transboundary EIA under the
existing domestic framework. This would include assessment and monitoring of
impacts on regional rainfall distribution and transboundary watercourses. China would
246
J.C. Moore et al., ‘Will China Be the First to Initiate Climate Engineering?’(2016) 4(12) Earth’s Future,
pp. 588–95, at 592; B. Bluemling, R.E. Kim & F. Biermann, ‘Seeding the Clouds to Reach the Sky: Will
China’s Weather Modification Practices Support the Legitimization of Climate Engineering?’(2019)
49(1) Ambio, pp. 365–73, at 366.
247
H. Lushan, ‘Has “Geoengineering”Arrived in China?’,China Dialogue, 9 Nov. 2020, available at:
https://chinadialogue.net/en/climate/how-to-supervise-geoengineering; S. Moore & F. Eyck, ‘China
Doesn’t Want a Geoengineering Disaster’,Foreign Policy, 21 Feb. 2023, available at:
https://foreignpolicy.com/2023/02/21/china-geoengineering-rules-climate-change.
248
UK House of Commons, Science and Technology Committee, ‘The Regulation of Geoengineering: Fifth
Report of Session 2009–10’, 18 Mar. 2010, pp. 15–6, available at: https://publications.parliament.uk/pa/
cm200910/cmselect/cmsctech/221/221.pdf; O. Edenhofer et al. (eds), ‘IPCC Expert Meeting on
Geoengineering: Meeting Report’, Lima (Peru), 20–22 June 2011, p. 45; National Research Council
Committee on Geoengineering Climate, Climate Intervention: Reflecting Sunlight to Cool Earth
(National Academies Press, 2015), p. 201, available at: http://www.nap.edu/catalog.php?
record_id=18988.
249
E.A. Parson, ‘Climate Engineering in Global Climate Governance: Implications for Participation and
Linkage’(2014) 3(1) Transnational Environmental Law, pp. 89–110, at 102; P. Williamson &
R. Bodle, Update on Climate Geoengineering in relation to the Convention on Biological Diversity:
Potential Impacts and Regulatory Framework, Technical Series No. 84 (Secretariat of the Convention
on Biological Diversity, 2016), p. 129.
250
Edney & Symons, n. 74 above, pp. 316–7.
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also need be more proactive in fulfilling its duty to cooperate with, notify, and consult with
potentially affected states, starting with greater transparency in sharing assessment and
monitoring results. Such measures could address the environmental and socio-economic
risks associated with weather modification, both within and across national borders,
and reduce regional geopolitical tensions.
A multilateral regional instrument could address deficiencies in China’s domestic
governance of large-scale atmospheric interventions. Such an instrument could
encourage notification and consultation with potentially affected countries and
assessment of transboundary risks. It could also establish a mechanism for information
sharing on weather and climate intervention research and development. In the absence
of such an agreement, however, the WMO has an important role to play in
strengthening international cooperation and information exchange. In the meantime,
China will need to revise its domestic framework to align with principles of customary
international law, potentially setting an example for other states to follow.
Manon Simon, Jan McDonald and Kerryn Brent 29
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