Mark George New

University of Cape Town | UCT · African Climate & Development Initiative

Climate change is making extreme climate events, such as droughts and floods, more severe all over the world. Working with nature could help reduce or completely remove these dangerous impacts of climate change. We developed a way to measure how much working with nature can reduce the impacts of extreme drought on society. We applied it to one of t...

This Policy Brief contributes to the goal of operationalizing loss and damage solutions and guiding global policies on the issues by identifying potential areas where science can readily support loss and damage solutions. This brief seeks to answer the following questions: 1. What is the current state of knowledge and the status of recognition of l...

The field of extreme event attribution (EEA) has rapidly developed over the last two decades. Various methods have been developed and implemented, physical modelling capabilities have generally improved, the field of impact attribution has emerged, and assessments serve as a popular communication tool for conveying how climate change is influencing...

Solar climate intervention refers to a group of methods for reducing climate risks associated with anthropogenic warming by reflecting sunlight. Marine cloud brightening (MCB), one such approach, proposes to inject sea‐salt aerosol into one or more regional marine boundary layer to increase marine cloud reflectivity. Here, we assess the potential i...

Despite widespread consensus that climate change poses a serious threat to global public health, very few studies have isolated the specific contributions of human-caused climate change to changes in morbidity and mortality. Here, we systematically review over 3,600 abstracts, and identify a dozen end-to-end impact attribution studies on human heal...

Background Temperatures across Africa are expected to rise at up to twice the rate of mean global temperatures, posing significant health threats to vulnerable communities. Prolonged exposure to high day- and night-time temperatures has been implicated in a myriad of adverse health outcomes. The built environment and inadequate housing can exacerba...

The field of extreme event attribution (EEA) has rapidly developed over the last two decades. Various methods have been developed and implemented, physical modelling capabilities have generally improved, the field of impact attribution has emerged, and assessments serve as a popular communication tool for conveying how climate change is influencing...

Most protected area impact research that uses counterfactuals draws heavily on quantitative methods, data, and knowledge types, making it valuable in producing generalizations but limited in temporal scope, historical detail, and habitat diversity and coverage of ecosystem services. We devised a methodological pluralistic approach, which supports s...

Impact attribution is an emerging transdisciplinary sub-discipline of detection and attribution, focused on the social, economic, and ecological impacts of climate change. Here, we provide an overview of common end-to-end frameworks in impact attribution, focusing on examples relating to the human health impacts of climate change. We propose a typo...

The Southwestern Cape (SWC) region in South Africa experienced a severe rainfall deficit between 2015–2017. The resulting drought caused the City of Cape Town to almost run out of water during the summer of 2017–2018. Using the self-organising maps approach, we identify and classify the synoptic circulation states over Southern Africa known to infl...

Stratospheric aerosol injection (SAI) is the theoretical deployment of sulphate particles into the stratosphere to reflect incoming solar radiation and trigger a cooling impact at the Earth’s surface. This study assessed the potential impact of SAI geoengineering on temperature and precipitation extremes over South Africa (SAF) and its climatic zon...

An important component of the risks from climate change arises from outcomes that are very unlikely, but whose impacts if they were to occur would be extremely severe. Examples include levels of surface warming, or changes in the water cycle, that are at the extreme of plausible ranges, or crossing of a climate system “tipping point” such as ice sh...

The changing probabilities of extreme climate and weather events, in terms of frequency, intensity, spatial extent, duration, and timing is one of the most noticeable and damaging manifestations of human-induced climate change. During the March-April-May (MAM) rainfall season of 2012, 2016 and 2018, Kenya experienced high rainfall that caused both...

In this Personal View, we explain the ways that climatic risks affect the transmission, perception, response, and lived experience of COVID-19. First, temperature, wind, and humidity influence the transmission of COVID-19 in ways not fully understood, although non-climatic factors appear more important than climatic factors in explaining disease tr...

South Africa is wrestling with increasing climate change impacts and how to respond. The 2022 IPCC Working Group II Report synthesises the latest evidence on climate change impacts, vulnerability and adaptation, and what this means for climate-resilient development. In this commentary, South African authors on the Report reflect on its key findings...

The Paris Agreement articulates a global goal on adaptation, which aims to ensure an ‘adequate adaptation response’ to the ‘global temperature goal’, and requires countries to report progress through periodic global stocktakes. However, there remain conceptual and methodological challenges in defining an adaptation goal and mixed evidence on what e...

Cape Town’s drought crisis grabbed global headlines in 2018 and its causes and solutions were – and continue to be – hotly debated. But managing water shortages and other climate change impacts have been integrated into the city’s urban policy-making for some time, in response to rapid urbanisation and uncertainty about the exact nature, timing and...

Quantifying how well Nature-based Solutions can offset anthropogenic climate change impacts is important for adaptation planning, but has rarely been done. Here we show that a widely-applied Nature-based Solution in South Africa – invasive alien tree clearing – reduces the impact of anthropogenic climate change on drought streamflow. Using a multi-...

Ecological restoration efforts at scale have been shown to play an important role in reducing human impact on the environment, improving climate change adaptation and halting extinctions globally. Upscaling restoration efforts needs funding, and therefore evidence of the benefits of restoration is needed. This study aims to contribute towards addre...

Ecological restoration efforts at scale have been shown to play an important role in reducing human impact on the environment, improving climate change adaptation and halting extinctions globally. Upscaling restoration efforts needs funding, and therefore evidence of the benefits of restoration is needed. The aims of this study are firstly to impro...

The use of climate services (CS) for the provisioning of climate information for informed decision-making on adaptation action has gained momentum. However, a comprehensive review of the literature to evaluate the lessons and experiences of CS implementation in the African agriculture sector is still lacking. Here, we present a systematic review (m...

Most socio-economic activities in Africa depend on the continent’s river basins, but effectively managing drought risks over the basins in response to climate change remains a big challenge. While studies have shown that the stratospheric aerosol injection (SAI) intervention could mitigate temperature-related climate change impacts over Africa, the...

New major road infrastructure projects are planned or underway across sub-Saharan Africa (SSA) and are expected to have complex, and often deleterious, impacts on natural ecosystems across the region. For this reason, it is necessary to review evidence of how and through which mechanisms, roads might affect these landscapes. We reviewed 137 peer re...

Assessing global progress on human adaptation to climate change is an urgent priority. Although the literature on adaptation to climate change is rapidly expanding, little is known about the actual extent of implementation. We systematically screened >48,000 articles using machine learning methods and a global network of 126 researchers. Our synthe...

Attributing the extent to which Nature-based Solutions (NbS) can offset emerging risk from anthropogenic climate change is a test of effectiveness for climate change adaptation, but has rarely, if ever, been done. Here we show that a widely applied NbS in South Africa – invasive alien tree clearing – can reduce the impact on hydrological drought se...

This paper identifies fundamental issues which prevent the effective uptake of climate information services in Nigeria. We propose solutions which involve the extension of short-range (1 to 5 days) forecasts beyond that of medium-range (7 to 15 days) timescales through the operational use of current forecast data as well as improve collaboration an...

The impact of alien plant invasions on ecosystems translates into major economic losses for nations across the globe. Freely available satellite imagery can be used to provide relevant data for effective management of alien plant invasions, especially for developing nations with limited budgets. However, detecting alien herbaceous and shrubby veget...

Disaster planning for slow-onset city-wide shocks will be become increasingly necessary, particularly as cities face increasingly severe climate hazards. This paper provides unique insight into the disaster planning and management that was undertaken by the City of Cape Town government in response to its most severe hydrological drought on record....

Over the last 50 years, studies have shown a decline in the use of mountain lands, a phenomenon termed land abandonment. We investigate the causal mechanisms of land use change in a mountain catchment important for regional water supplies in the southwestern Cape of South Africa. Uniquely, we include nature-based recreational land use types typical...

Investments to promote sustainable land-use within critical river catchment areas are often undertaken to provide benefits to society. Investments generally aim to protect or restore ecological infrastructure—the underlying framework of ecosystems, functions and processes that supply ecosystem services—for multiple benefits to society. However, the...

Real-world experience underscores the complexity of interactions among multiple drivers of climate change risk and of how multiple risks compound or cascade. However, a holistic framework for assessing such complex climate change risks has not yet been achieved. Clarity is needed regarding the interactions that generate risk, including the role of...

We present the first systematic, global stocktake of the academic literature on human adaptation. We screen 48,316 documents and identify 1,682 articles that present empirical research documenting human efforts to reduce risk from climate change and associated hazards. Coding and synthesizing this literature highlights that the overall extent of ad...

Purpose The nature of the collaborations that exists among the organizations in the climate change and agriculture sectors can influence the tailoring of climate forecasts into information useable for adapting agricultural practices to the risks posed by climate change. Also, the extent to which farmers are integrated into this organizational colla...

Although climate information can aid farmers’ capacity to adapt to climate change, its accessibility and adoption by subsistence farmers hinge on the collaboration between farmers and climate information providers. This paper examines collaborations among actors in the process of climate information production and dissemination in the Namibian agri...

Many insured assets can be damaged by weather and weather-related events. Tropical cyclones and droughts are two weather phenomena that persistently cause damage. In developing countries, index-based insurance is increasingly being used to enable rapid payouts to support disaster recovery. These products can be taken up at the national level, in Af...

Operationalising advances in remote sensing for invasive alien plant management remains a major challenge, despite its proven value globally. There is also a lack of detailed remote sensing studies in water towers, for example the southwestern Cape of South Africa, where invasive alien trees threaten water security. There is a need for cost-effecti...

Anthropogenic forcing of the climate is estimated to have increased the likelihood of the 2015–2017 Western Cape drought, also called ‘Day Zero’ drought, by a factor of three, with a projected additional threefold increase of risk in a world with 2 °C warming. Here, we assess the potential for geoengineering using stratospheric aerosols injection (...

Mean surface temperature is projected to rise by about 4.4 ◦C by the end of the century compared to the period between 1976 and 2005 when following the most extreme scenario of the greenhouse gas emissions pathway (Krishnan et al., 2020). With this rise in mean temperature, there is a lot of uncertainty on how weather and climate extremes would un...

Urgent sustainability challenges require effective leadership for inter- and trans-disciplinary (ITD) institutions. Based on the diverse experiences of 20 ITD institutional leaders and specific case studies, this article distills key lessons learned from multiple pathways to building successful programs. The lessons reflect both the successes and f...

Context : It is now widely accepted that the climate is changing, and that societal responses will need to be rapid and comprehensive to prevent the most severe impacts. A key milestone in global climate governance is to assess progress on adaptation. To-date, however, there has been negligible robust, systematic synthesis of progress on adaptation...

Context : It is now widely accepted that the climate is changing, and that societal response will need to be rapid and comprehensive to prevent the most severe impacts. A key milestone in global climate governance is to assess progress on adaptation. To-date, however, there has been negligible robust, systematic synthesis of progress on adaptation...

The multi‐year (2015–2017) drought in the South West of the Western Cape (SWC) caused a severe water shortage in the summer of 2017–2018, with damaging impacts on the local and regional economy, and Cape Town being in the news one of the first major cities to potentially run out of water. Here, we assess the links between the rainfall deficits duri...

Adaptation to climate change is challenging in terms of managing knowledge flow among diverse actors. This paper examines the roles of key actors in Namibia in the production and dissemination of climate adaptation knowledge. The intention was to identify opportunities for enhancing collaboration among actors to facilitate knowledge flow and uptake...

We have examined the annual and seasonal impacts of 1.5°C and 2°C global temperature rise (GTR) on temperature and rainfall change over all the states of India under two Representative concentration pathways, RCP 8.5 and RCP 4.5, using all Coupled Model Inter Comparison Project CMIP5 Models. 35% of the country is projected to witness a temperature...

The participating member nations in Paris at the 2015 convention of the United Nations Framework Convention on Climate Change (UNFCCC) resolved to maintain the rise in global average temperature to a level much less than 2.0 o C compared to pre-industrial levels. It was also committed that the parties would continue with all-out endeavor to limit w...

This study provides the first assessment of CMIP5 model performances in simulating southern Africa (SA) rainfall variability in austral summer (Nov–Feb), and its teleconnections with large-scale climate variability at different timescales. Observed SA rainfall varies at three major timescales: interannual (2–8 years), quasi-decadal (8–13 years; QDV...

This study aims at assessing the vulnerability of six key crops (maize, beans, cassava, millet, groundnuts, and sweet potatoes) to variations in growing season precipitation at both the national and regional scale (southwest) in Uganda. To achieve this objective, a vulnerability model that is a function of sensitivity, exposure and adaptive capacit...

Leaders of sustainability research organizations need to provide an environment where interdisciplinary and transdisciplinary science flourish. Developing the necessary leadership skills and attributes requires new, targeted training programmes.

Studies of climate change at specific intervals of future warming have primarily been addressed through top-down approaches using climate projections and modelled impacts. In contrast, bottom-up approaches focus on the recent past and present vulnerability. Here, we examine climate signals at different increments of warming and consider the need to...

Arctic climate change has the potential to affect access to semi-permanent trails on land, water and sea ice, which are the main forms of transport for communities in many circumpolar regions. Focusing on Inuit Nunangat (the Inuit homeland in northern Canada), trail access models were developed drawing upon a participatory process that connects Ind...

Habitat loss and more recently, climate change are primary challenges to the effectiveness of protected area networks (PANs) in species conservation within many archipelagic biodiversity hotspots across the globe. An environmental niche model (ENM) of 11 high-conservation-value tree species was used to assess the effectiveness of the PAN within the...

Different framings of effectiveness will influence the entire adaptation process, from identifying the vulnerabilities that adaptation aims to address, to determining who benefits and who is left behind, which adaptation actions are chosen and funded, and how they are implemented. Justice, governance, community-based adaptation, and sustainability...

In the period 2015-2017, the Western Cape region has suffered from three consecutive years of below average rainfall - leading to a prolonged drought and acute water shortages, most prominently in the city of Cape Town. After testing that the precipitation deficit is the primary driver behind the reduced surface water availability, we undertake a m...

Introduction: The intersection of health and climate change is often absent or under-represented in sub-national government strategies. This analysis of the literature, using a new methodological framework, highlights priority focus areas for a sub-national government response to health and climate change, using the Western Cape (WC) province of S...

n Kenya, pastoralists have utilized natural grasslands using practices that often resultin overgrazing, low productivity and low income. Such practices have caused environmentalproblems, which could be exacerbated by climate change. Although knowledge on practicesthat increase pastoralists’ capacity to adapt to climate and environmental challenges...

Purpose Between 2006 and 2016, local communities in semi-arid Bobirwa sub-district in the Limpopo Basin part of Botswana had endured notable fluctuations in the delivery of critical ecosystem services. These changes have been coupled with adverse effects on local people’s livelihood options and well-being. However, a few such studies have focussed...