Panmao Zhai's research while affiliated with Nanjing University of Information Science & Technology and other places

Publications (70)

Article
Hot extremes and ozone pollution have long been known detrimental to public health, but until very recently disproportionate health impacts from their joint occurrence-compound hot and ozone extremes (CHOEs)-have not been sufficiently aware of. Based on high-quality observations of air temperature and surface ozone concentration, we here examined t...
Article
Full-text available
In summer, the middle and lower reaches of the Yangtze River (MLYR) often suffers from severe floods as a result of a dominant intraseasonal oscillation (ISO) of rainfall with the quasi-period of 25−60 days. 75% of flooding events during summers of 1961−2022 are found to occur following wet phases of the 25−60-day ISO in rainfall. This study object...
Article
Ecosystem-scale water use efficiency (WUE), as a quantification of the coupling between carbon and water cycle, determines whether vegetation could survive under severe drought stress. Nevertheless, how extreme droughts affect ecosystem-scale WUE and its difference among regions and biomes are still poorly understood. In this study, using data-orie...
Article
Based on China’s daily precipitation data of 2415 stations and ERA5 hourly reanalysis data from 1961 to 2019, the station-based and regional precipitation events over Northwest China (NWC) are identified and sorted into persistent precipitation (PP, duration & 2 days) events and non-persistent precipitation (NPP, duration = 1 day) events; and then...
Article
Full-text available
Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decisio...
Article
Full-text available
With the aggravation of climate change, drought has become a more prominent extreme event with serious consequences. The selection of drought indices is crucial for accurate quantification and assessment of drought change and its impacts. In this study, we first evaluated the standardized precipitation evapotranspiration index (SPEI) at different t...
Preprint
Full-text available
Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decisio...
Article
We report here extreme daytime and nighttime temperatures, severe heatwaves, and compound hot events recorded in China’ five most densely populated city clusters in summer 2022. New records were set, with daytime maximum temperatures > 42°C in cities along the Yangtze River valley and extreme nighttime temperatures > 30°C. Widespread prolonged heat...
Article
The Qinghai-Tibetan Plateau (Q-TP hereafter) has experienced dramatic warming in recent decades, resulting in severe effects on the ecosystems and downstream. However, none of previous studies investigated elevationdependency temperature trend with the high resolution over the long-term period. Based on monthly temperature dataset with 0.1◦ develop...
Article
Full-text available
Tropical cyclones (TCs) seriously threaten the safety of human life and property especially when approaching a coast or making landfall. Robust, long-lead predictions are valuable for managing policy responses. However, despite decades of efforts, seasonal prediction of TCs remains a challenge. Here, we introduce a deep-learning prediction model to...
Article
Full-text available
A double-plume convective parameterization scheme is revised to improve the precipitation simulation of a global model (Global-to-Regional Integrated Forecast System; GRIST). The improvement is achieved by considering the effects of large-scale dynamic processes on the trigger of deep convection. The closure, based on dynamic CAPE, is improved acco...
Technical Report
Full-text available
The IPCC AR6 Synthesis Report is based on the three Working Group contributions to the AR6 as well as on the three Special Reports prepared in this assessment cycle.
Article
Full-text available
Record-breaking extreme precipitation occurred over the Yangtze River Valley (YRV) in June–July 2020. The impact of climate change on this event is examined from the perspectives of key physical processes including synoptic-scale circulation pattern and tropical sea surface temperature (SST) forcing based on self‐organizing map approach and the reg...
Article
Human society and ecosystems are impacted by climate extremes more than by climate averages. In contrast with climate extremes that are driven by individual climatic variables, compound climate extremes stem from a combination of multiple climatic drivers and usually lead to more severe risks than the former extremes do. The influences of the drive...
Article
Full-text available
During the recent decades, summer precipitation has increased over the western and northeastern Tibetan Plateau (TP) and decreased over the southeastern TP. This study investigates the effects of anthropogenic forcing and internal variability on summer rainfall changes over the TP during 1979–2013. It is shown that the variations in atmospheric cir...
Article
Knowledge about the regionalization of the planetary boundary layer (PBL) height (PBLH) remains unclear for such a huge country like China, largely to the limited observations. By using K-means clustering of summer radiosonde-derived PBLHs, combined with land surface related factors, we classified China into six regions, including Northeast China,...
Article
Full-text available
It is unequivocal that human influence has warmed the planet, which is seriously affecting the planetary health including human health. Adapting climate change should not only be a slogan, but requires a united, holistic action and a paradigm shift from crisis response to an ambitious and integrated approach immediately. Recognizing the urgent need...
Article
The latest IPCC AR6 pointed out that some climate extremes, such as temperature extremes and droughts have increased in frequency and/or intensity significantly under global warming background. Based on in situ observations, ERA5 hourly reanalysis and CRA-Land surface reanalysis data, this study described the occurrence and evolution process of com...
Article
Full-text available
East Asia is undergoing significant climate changes and these changes are likely to grow in the future. It is urgent to characterize both the mechanisms controlling climate and the response of the East Asian climate system at global warming of 1.5 and 2 °C above pre-industrial levels (GW1.5 and GW2 hereafter). This study reviews recent studies on E...
Article
Full-text available
Tropical cyclones (TCs) and heatwaves are amongst the most deadly and costly natural hazards. Despite considerable advances in understanding each of them, their occurrences in rapid sequence (e.g., in a week) that introduce disproportionately large impacts to infrastructure and human health have received far less attention. Based on dynamical downs...
Article
Full-text available
Plain Language Summary Despite plentiful knowledge on heatwaves' impacts on human health, little has been known about heatwaves' implication for extreme rainfall and the resulting floods. After experiencing sustained sweltering weather, people are sometimes eager for cooling brought about by heavy precipitation; however, subsequent rainfall, if int...
Article
Full-text available
Wetlands are large sinks of carbon dioxide (CO2) and sources of methane (CH4). Both fluxes can be altered by wetland management (e.g., restoration), leading to changes in the climate system. Here, we use multiple models to assess CH4 emissions and CO2 sequestration from the wetlands in China and the impacts on climate under three climate scenarios...
Article
Full-text available
The magnitude asymmetry between positive and negative extreme anomalies in gross primary productivity (GPP) and the underlying mechanism have been investigated based on daily records from the data-driven and in-situ datasets. Distinct magnitude asymmetries of daily GPP extreme anomalies (DGEAs) have been identified between forested and non-forested...
Article
The response of vegetation to global warming is closely related to human living environment, and uncertainty in understanding the response remains. This study aims to investigate the effects of CO2, temperature and precipitation changes under global warming on natural vegetation in Asia. The biophysical/dynamic vegetation model SSiB4/TRIFFID was em...
Article
The Meiyu 2020 with record-breaking amount of precipitation, widespread area coverage and anomalous northern location brought about great social and economic impacts in China. However, the spatial property of anomalous rain-belt for such a catastrophic Meiyu is not well predicted. In this study, high-resolution in-situ observation and reanalysis da...
Article
The greening and browning of global vegetation are driven by various processes such as climate change, CO2 fertilization, and land management, etc. From the perspective of the vegetation-water-heat relationship, the above processes can be briefly summarized as two types of eco-hydrological processes: 1. dryness change; 2. usage change. We here pres...
Article
Full-text available
Climate change is expected to result in more frequent and intense heat waves (HWs) in South Asia (SA). The simultaneous increases in temperature and population will exacerbate the population exposure to future HWs. Here we estimate the future population exposure to daytime and nighttime HWs in SA using the Coupled Model Intercomparison Project 6 (C...
Article
Full-text available
This study presents the improved future projections of the climate “warming—wetting” trend and climate extremes with different return periods in Northwest China at different global warming levels. The projections are based on the Coupled Model Intercomparison Project phase 6 (CMIP6) simulations constrained by the high-resolution observation dataset...
Article
Full-text available
There have been considerable high-impact extreme events occurring around the world in the context of climate change. Event attribution studies, which seek to quantitatively answer whether and to what extent anthropogenic climate change has altered the characteristics—predominantly the probability and magnitude—of particular events, have been gainin...
Preprint
Full-text available
During the recent decades, summer precipitation has increased over the western and northeastern Tibetan Plateau (TP) and decreased over the southeastern TP. This study investigates the effects of external forcing and internal variability on summer rainfall changes over the TP during 1979-2013. It is shown that the variations in atmospheric circulat...
Article
The magnitude asymmetry between positive and negative extreme anomalies in gross primary productivity (GPP) and the underlying mechanism have been investigated based on daily records from the data-driven and in situ datasets. Distinct magnitude asymmetries of daily GPP extreme anomalies (DGEAs) have been identified between forested and non-forested...
Article
Northeastern China has experienced a significant increase in summer compound hot and dry events (CHDEs), posing a threat to local agricultural production and sustainable development. This study investigates the detectable anthropogenic signal in the long-term trend of CHDE and quantifies the contribution of different external forcings. A probabilit...
Article
Two global experiments were carried out to investigate the effects of dynamic vegetation processes on numerical climate simulations from 1948 to 2008. The NCEP Global Forecast System (GFS) was coupled with a biophysical model, the Simplified Simple Biosphere Model (SSiB) version 2 (GFS/SSiB2), and it was also coupled with a biophysical and dynamic...
Article
Full-text available
Precipitation extremes, such as the record-breaking Meiyu characterized by frequent occurrences of rainstorms that resulted in severe flooding over the Yangtze—Huai River valley (YHRV) in June–July 2020, are always attracting considerable interest, highlighting the importance of improving the forecast accuracy at the medium-to-long range. To elevat...
Article
Earth system models (ESMs) have been widely used to simulate global terrestrial carbon fluxes, including gross primary production (GPP) and net primary productivity (NPP). Assessment of such GPP and NPP products can be valuable for understanding the efficacy of certain ESMs in simulating the global carbon cycle and future climate impacts. In this w...
Article
Full-text available
Plain Language Summary Meiyu rainfall over the middle‐lower reaches of Yangtze River (MLYR) is characterized by strong intraseasonal oscillations (ISOs, with the period of 10–90 days). While the quasi‐biweekly (10–20‐day) oscillation of MLYR rainfall has been well acknowledged, we found that significant 25–60‐day ISOs of rainfall also exist in eigh...
Article
Extremely anomalous features of Meiyu in 2020 over the Yangtze-Huai River basin (YHRB) and associated causes in perspective of the large-scale circulation are investigated in this study, based on the Meiyu operational monitoring information and daily data of precipitation, global atmospheric reanalysis, and sea surface temperature (SST). The main r...
Article
Full-text available
Plain Language Summary Policy‐makers and stakeholders have long been informed of that climate change has altered and continues to alter the profile of extremes, for example, frequency, magnitude, duration, and/or seasonality, creating unprecedented events with catastrophic consequences. But they have been seldom told that a changing climate is also...
Article
We analyzed the spatiotemporal variations in surface air temperature and key climate change indicators over the Tibetan Plateau during a common valid period from 1979 to 2018 to evaluate the performance of different datasets on various timescales. We used observations from 22 in-situ observation sites, the CRA-40/Land (CRA) reanalysis dataset, the...
Article
Full-text available
Under the background of global change,the cryosphere and atmosphere over the Tibetan Plateau (TP)are changing rapidly,which seriously affects the ecological environment of“Asian Water Tower”and“the Third Pole”. This paper reviews some issues in the research on climate change over the TP in recent years,including the change of extreme climate events...
Article
Full-text available
Wetting in the south while drying in the north during the last few decades constitutes the well-known ‘southern flood–northern drought’ (SFND) precipitation pattern over eastern China. The fingerprint of anthropogenic influence on this dipole pattern of regional precipitation trends has not been confirmed, especially for forced changes in relevant...
Article
Full-text available
China's climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes of the climate have exerted substantial impacts on water resources, agriculture, ecosystems, and human health. Attributing past changes to causes provides a scientific foundation for national and international...
Article
Persistence is an important property of precipitation and its related impacts. However, changes in persistent precipitation and the possible underlying mechanisms in the context of global warming have not yet been discussed in sufficient depth. In this study, the changes in persistent precipitation in summer and related atmospheric circulation patt...
Article
Full-text available
Future changes in the frequency of extreme drought events are of vital importance for risk assessment and relevant policy making. But a reliable estimation of their probability is intrinsically challenging due to limited available observations or simulations. Here, we use two large ensemble simulations, 50 members from CanESM2 and 40 members from C...
Article
Full-text available
Plain Language Summary Changes to weather and climate extremes at individual locations can be highly uncertain due to natural variability. Much of the natural variability in precipitation extremes occurs on small spatial scales, and thus analyzing changes at different locations in a region with a field significance test can help extract information...
Article
Warming amplification over the Arctic Pole (AP hereafter) and Third Pole (Tibetan Plateau, TP hereafter) can trigger a series of climate responses and have global consequences. Arctic amplification (AA) and Tibetan amplification (TA) are the most significant characteristics of climate change patterns over the two Poles. In this study, trends, mecha...
Article
Full-text available
Warming has resulted in increases in frequency, intensity and/or duration of droughts in most land regions over the globe. Nevertheless, knowledge on how ecosystem water use efficiency (WUE) responds to extreme drought stress and whether the responses are affected by drought timing is still limited. In this study, we examined the changes in ecosyst...
Article
Full-text available
Traditional univariate analysis on weather and climate extremes failed to consider temporally compounding events and the resulting cascading impacts. A case in point is a sequence of flood and heatwave within a week, which slows recovery and amplifies damages. We show that across China, floods and heatwaves seldom occurred serially within seven day...
Article
Full-text available
Compound extreme events always cause severe impacts on human society and the natural system, especially in the populated areas. However, studies on their changes depend on definitions of the related extreme events. In this study, a newly defined compound drought and hot extreme events (CDHEEs) index based on the day-night concurrent hot extreme ind...
Article
Full-text available
Detecting long-term changes in precipitation extremes over monsoon regions remains challenging, due to large observational uncertainty, high internal variability at the regional scale and climate models’ deficiency in simulating monsoon physics. This is particularly true for Eastern China, as illustrated by limited yet controversial detection resul...
Article
Full-text available
Compound drought and heat event (CDHE) causes severe impacts on agriculture, ecosystem, and human health. Based on daily maximum surface air temperature and meteorological drought composite index data in China, changing features of CDHEs in warm season from 1961 to 2018 is explored at a daily time scale based on a strict and objective definition in...
Article
Short duration extreme precipitation has devastating Impacts on city area. Local urbanization effects, superimposed upon regional climate change, complicate examination of long‐term changes in short duration precipitation extremes in urban areas. Based on high‐quality rain gauge observations of summertime hourly precipitation in Beijing Region over...
Article
Full-text available
Using data collected from a specially designed experiment at the Dunhuang Station (40°10′N, 94°31′E, 1150 m) from September 2017 to September 2018, we have characterized the influences of soil moisture and solar altitude on surface spectral albedo in an arid area. The specific settings of our experiment allowed us to minimize the influences of unde...
Article
Full-text available
Plain Language Summary The Coordinated Regional Climate Downscaling Experiment (CORDEX) provides spatially detailed climate change projections for different regions across the world. These projections are obtained through numerical models that solve the governing equations of the atmosphere over spatial domains, which typically cover continental ar...
Article
Full-text available
To better understand the long-term influences of the 1.5°C target, we provide an assessment of the changes in climate extremes under same warming level but at different timings, based on the magnitude of change, the internal variability, and the model agreement derived from CMIP5. Our findings imply that the changes in climate extremes and their im...
Article
Full-text available
Climate change is not only about changes in means of climatic variables such as temperature, precipitation and wind, but also their extreme values which are of critical importance to human society and ecosystems. To inspire the Swedish climate research community and to promote assessments of international research on past and future changes in extr...
Chapter
Full-text available
This is the Summary for Policy Makers of the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate, as approved by the IPCC member countries at the Plenary in Monaco, 25 September 2019.
Article
Full-text available
Abstract The Paris Agreement has motivated rapid analysis differentiating changes in frequency/intensity of weather and climate extremes in 1.5 versus 2 °C warmer worlds. However, implications of these global warming levels on locations, spatial scales, and emergence timings of hot spots to extremes are more relevant to policy‐making but remain str...
Chapter
Full-text available
This is the Summary for Policy Makers of the IPCC Special Report on Land and Climate Change, as approved by the IPCC member countries at the Plenary in Geneva, Aug 2-7 2019.
Article
Full-text available
Based on the daily precipitation data of the Huai River basin (HRB) and NCEP/NCAR reanalysis data from 1960 to 2014, the study examines the spatio‐temporal characteristics of summer extreme precipitation (SEP), explores the statistical relationship between the changes of SEP in the HRB and the East Asian summer monsoon (EASM), and further investiga...
Book
The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides regular assessments of the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report is a comprehensive assessment of our...
Article
Full-text available
Weather and climate extremes impose serious impacts on natural and human systems. In its fifth assessment report (AR5) and a special report Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX), the Intergovernmental Panel on Climate Change provided a thorough assessment of observed and projected changes in...
Article
Full-text available
During the past two decades since 1997, eastern China has experienced a warming hiatus punctuated by significant cooling in daily-minimum temperature (Tmin), particularly during early–mid winter. By arbitrarily configuring start and end years, a 'vantage hiatus period' in eastern China is detected over 1998–2013, during when the domain-averaged Tmi...

Citations

... T he major agencies tracking global surface temperature anomalies (GSTA) rank 2022 as the 5-6th warmest on record [1][2][3] . That global warming continues is clear 4 , and apparent in the markedly strengthening impacts felt around the world 5 . Satellites and ocean data also document a strengthening uptake of energy in the Earth system, related to an increasing imbalance between incoming solar radiation and energy reemitted to space 6,7 . ...
... In July and August of 2022, the YRV experienced an unprecedented heat event, combined with a precipitation deficit, which ultimately drove the occurrence of a severe hydrological drought (Lu et al., 2023;Yuan et al., 2023). This can be seen from the strongest Tmax in July and August and rapid drying of the surface SM (Figs. 3a and f). ...
... As the most commonly used herbicide (Benbrook, 2016;Mendes et al., 2021), glyphosate has been the subject of numerous studies highlighting structural and functional changes in microbial communities following exposure (Luis et al., 2011;Pizarro et al., 2016;Xiao et al., 2023). Currently, the detrimental effects of eutrophication and herbicide use on freshwater ecosystems have already been observed and are anticipated to worsen (Masson-Delmotte et al., 2021). Investigating how microbial community assembly responds to these stressors can provide insights into the resulting negative effects. ...
... The simulated global and regional rainfall features of GRIST-PhysC, however, are overall inferior to those of GRIST-PhysW. For example, with increasing local resolution, GRIST-PhysW better simulates the eastwardpropagating rainfall episodes downstream of the Tibetan Plateau (Zhang et al., 2021), while GRIST-PhysC does not support such a beneficial resolution sensitivity, even with a refined tuning of certain physical processes (Li et al., 2023). ...
... Particularly noteworthy is the discernible transition from vegetation to bare land, coupled with the metamorphosis of urban areas and forested landscapes, which accentuates the dynamic milieu that characterizes the study area. These findings resonate with an established body of literature that underscores the transformational impacts of human interventions, climate oscillations, and surging urbanization trends (Ayeni et al. 2023;Syvitski et al. 2022;Yu et al. 2023). ...
... High Mountain Asia (HMA) has experienced a spatial imbalance in water resources in recent decades, partly because of a dipolar pattern of precipitation changes known as South Drying-North Wetting 1 . These changes can be influenced by both human activities and internal climate variability 2,3 . Although climate projections indicate a future widespread wetting trend over HMA 1,4 , the timing and mechanism of the transition from a dipolar to a monopolar pattern remain unknown. ...
... We also obtain the planetary boundary layer height (PBLH) from the reanalysis dataset to describe the evolution of PBLH at the Canton Tower. Previous studies have evaluated the PBLH from several widely used reanalysis products, including the fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis of the global climate (ERA5), the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), the National Centers for Environmental Prediction final global reanalysis data (FNL), and the coupled ECMWF atmospheric reanalysis of mediumrange weather (CERA) across China (Guo et al., 2021;Xu et al., 2022), with radiosounding observations. These studies highlight the robustness and suitability of estimating the PBLH using the ERA5 reanalysis dataset (https:// cds.climate.copernicus.eu/#!/search?text=ERA5, ...