Extreme High Temperature Events Research Articles

Future projections of temperature extremes over East Asia based on a deep learning downscaled CMIP6 high-resolution (0.1°) dataset

East Asia, with its diverse landscapes and dense population, is particularly vulnerable to the impacts of climate change. This study utilizes the Climate Change for East Asia with Bias corrected UNet Dataset (CLIMEA-BCUD), a high-resolution and bias-corrected dataset of future climate projections, to assess the potential changes in temperature extremes across East Asia under three Shared Socioeconomic Pathways (SSPs) scenarios (SSP1–2.6, SSP2–4.5, and SSP5–8.5). The accuracy of CLIMEA-BCUD is verified through comparisons with observational data during the baseline period (1981–2010). CLIMEA-BCUD demonstrates remarkable accuracy in simulating the intensity, frequency and duration of extreme temperature events, although overestimation exists for the duration of warm spell and cold spell in some areas of India and Indo-China. Its high spatial resolution allows it to provide more spatial details of the distribution of extreme temperature events. In general, CLIMEA-BCUD outperforms the global climate models with smaller biases and lower root mean square errors. In the future, CLIMEA-BCUD projects a greater increase in TNn than TXx across East Asia. TX90p and TN90p are projected to increase, especially over India and Indo-China. Warm spell duration shows a robust increase, particularly in the Tibetan Plateau and Indo-China, while the cold spell duration will shorten. East Asia will see more frequent record-breaking extreme high-temperature events. Extreme temperature indices related to frequency and duration are more likely to break historical records than intensity indices. The Tibetan Plateau and Xinjiang emerge as hotspots for record-breaking frequency and duration of extreme temperature events.

Changes in compound hot extremes over the mid-high latitudes of Asia and underlying mechanisms

Abstract This study investigates the spatiotemporal variations of summer frequency of day-nighttime compound extreme high-temperature events (FCEHE) in the mid-high latitudes of Asia (MHA) from 1979 to 2014. Results show that FCEHE has shown an upward trend with fluctuations, especially in Mongolia-Baikal. The descending anomaly caused by the anomalous high pressure over the Mongolia-Baikal results in reduced cloud cover, which increases solar radiation reaching the ground, favoring the higher FCEHE. This process is consistent during the daytime and nighttime periods, with relatively limited nighttime solar radiation, potentially compensated by the increased downward longwave radiation to sustain the extreme high temperatures. This benefit process is closely connected with two main factors: the increased sea ice in the Barents Sea during spring and the anomalously warm sea surface temperature (SST) in the Northwest Pacific during summer. The increased sea ice can affect the Eurasia teleconnection (EU), while the warm SST affects the Pacific-Japan/East Asia–Pacific pattern (PJ/EAP). Subsequently, these factors further modulate the circulation anomalies and then FCEHE.

Effects of Orography on the High-Temperature Event on 22 June 2023 in North China

An extreme high-temperature event occurred in North China on 22 June 2023, with the maximum temperature reaching 41.8 °C. The high-temperature centers preferentially occurred at the foothills of the Taihang and Yanshan Mountains, indicating an important role of the underlying orography. In the present work, we study the orographic effects of this extreme high-temperature event according to high-resolution numerical simulations using the Weather Research and Forecasting model. The results show that the presence of the mountains in North China contributed notably to the high-temperature event, which can enhance the 2 m air temperature by up to 3 °C. In the daytime, the enhancement of temperature is primarily due to the diabatic heating of sensible heat flux at the terrain surface caused by solar shortwave radiation, whereas the well-known foehn effect has little contribution. Indeed, the dynamically forced downslope flow of foehn is totally suppressed by the upslope flow of the thermally driven mountain-plain circulation. In the nighttime, the sensible heat flux at the terrain surface changes to weakly negative, given the cooling of land surface longwave radiation. As a result, the enhancement of near-surface temperature at the terrain foothill is dominated by the adiabatic warming of downslope flow. Yet, the near-surface temperature far away from the mountain is enhanced by the subsidence warming of a synoptic anomalous anti-cyclone, which is induced by the diabatic heating over the mountains in the daytime. These findings help improve the understanding of the thermal and dynamical effects of orography on the occurrence of high-temperature events.

Co-designed agro-climate indicators identify different future climate effects for grape and olive across Europe

Co-design processes involving the scientific community, practitioners, end users and stakeholders can efficiently characterize harmful weather events during the growing season that potentially result in losses of crop yield and quality. This study builds on the experience of the EU Horizon 2020 project MED-GOLD for grape and olive. The identified agro-climate indicators are extended from the MED-GOLD regions to the entire ones where grape and olive are currently grown in Europe and Turkey, and used to assess climate change impacts with intrinsic adaptation relevance stemming from the co-design process. Before 2000, only a low fraction of the European grape and olive growing areas was exposed to extreme weather events as revealed by the agro-climate indicators, but this has changed rapidly afterward. Projections show increasingly widespread extreme high temperature events from 2020 to 2080. Approximately one-third of grapevine regions and over half of olive cultivation areas are expected to experience extreme drought conditions. Additionally, the frequency of compound extreme events will increase in the future, especially in the Mediterranean region and under the high-end emission scenario RCP8.5. This outcome calls for a new decision-making mindset that embeds expected levels of climate variability and extremes as the “new normal” for grape and olive in Europe. This will facilitate deployment of the required biophysical, economic and policy adaptation tools.

Temporal characteristics of extreme high temperatures in Wuhan since 1881

The construction and analysis of daily temperature data series in long enough a time period is important to understand decadal to multi-decadal variability and changing trends in extreme temperature events. This paper reports a new analysis of extreme temperature indices over the last 140 yr in Wuhan, China, with an emphasis on changes in extreme high temperature changes. The daily temperature data from 9 stations from 1881 to 1950 and 1 modern station from 1951 to 2020 were used for the analysis. Based on the data, and the commonly used extreme temperature indices, the variations and long-term trends of extreme high temperature events in Wuhan since 1881 were analyzed. The results show that there was no clear warming trend in maximum temperature, but a quite large inter-annual and inter-decadal fluctuation. In contrast, there was a very significant increase in minimum temperature, with a large upward trend overall. The extreme temperature indices exhibit a periodic variability, and frequent extreme heat events have been experienced over the last 140 yr in Wuhan. Most extreme temperature indices did not exhibit remarkable changes during the first half of the period analyzed. However, the majority of the extreme temperature indices showed significant upward trends over the latter half of the 140 yr period. The possible causes of the observed changes in the extreme high temperature events in the different time periods are also discussed.

Impacts of Extreme Precipitation and Diurnal Temperature Events on Grassland Productivity at Different Elevations on the Plateau

The impact of extreme climate events on vegetation growth and ecosystem function has garnered widespread attention, particularly in plateau regions, which are facing increasingly severe environmental pressures. This study employs the Events Coincidence Analysis (ECA) method to examine the impacts of extreme climate events on the Net Primary Productivity (NPP) of vegetation in plateau regions. Specifically, we focus on the unique phenomenon of asymmetric daytime and nighttime warming and evaluate the compounding effect of extreme precipitation with extreme temperature events. The results indicate that grassland NPP has higher overall sensitivity and Coincidence Rates (CR) to extreme precipitation events compared to extreme temperature events. Specifically, extreme drought events significantly negatively impact grassland NPP, and the sensitivity of NPP increases with the severity of extreme drought events. In lower elevations (<3200 m), grassland NPP shows a strong response to extreme precipitation events, with sensitivity decreasing with increasing elevation, especially for alpine meadows. Extreme high-temperature events contributed significantly to NPP in mid to high elevations (3000–5000 m). Compound extreme climate events amplify the average coincidence degree with NPP anomalies, with extreme precipitation events playing a major role in compound effects. The CR of compound climate events can reach above 0.6, reflected in the anomaly increase of NPP in temperate grasslands at higher elevations caused by compound events of extremely wet and extremely high temperatures.

Who is the major player for 2022 China extreme heat wave? Western Pacific Subtropical high or South Asian high?

A long-lasting, wide-ranging, and record-breaking extreme high-temperature (EHT) event hit China in the summer of 2022, causing adverse impacts on electricity supply, agriculture, and people's livelihoods. The abnormal persistence of the eastward-shifted South Asian high (SAH) in the upper troposphere was the dominant driver of the durative enhancement of EHT and can explain approximately 55.7% of the event's occurrence, compared to the 14.5% contribution of western Pacific Subtropical high (WPSH) to this event. As the SAH extends eastward, the East Asian westerly jet tends to shift northward, the combination of which could have caused persistent descending motion over East China and thus evoked the EHT. The eastward shift of the SAH in summer 2022 was jointly affected by the preceding-spring record-low snow cover over the Tibetan Plateau, the contemporaneous record-low aerosol levels in East China, the record-high precipitation of Indian subcontinent and the record-high sea surface temperature in the North Atlantic since 1990. Notably, during 1990–2022, for the 2022-like EHT, only 38.43% of that is related to the couple of westward-shifting WPSH and eastward-extending SAH. Approximately 47.6% of 2022-like EHT is just corresponding to an abnormally eastward-extending SAH, suggesting the non-negligible role of SAH in the China's EHT prediction.

Anthropogenic Contribution to the Unprecedented 2022 Midsummer Extreme High-Temperature Event in Southern China

Anthropogenic influence contributed approximately 61% to the extreme high-temperature event in southern China in midsummer 2022, according to a dynamic adjustment methodology and supported by optimal fingerprinting analysis of CMIP6 models.

Exponential increases in high-temperature extremes in North America

Global warming in the 21st century will alter the frequency of extreme climatic events, such as high-temperature anomalies and “heat waves”. Observations of extreme high temperatures during recent decades have detected upward trends in their frequency of occurrence, and recent state-of-the-art Global Climate Models (GCMs), e.g., Climate Model Intercomparison Projects (CMIPs), notably CMIP5 and CMIP6, have predicted acceleration of temperature trends and high-temperature events by 2100 under projected greenhouse-gas emission scenarios. Hence, the 21st century is expected to experience substantial shifts in the occurrence of extreme events, where present-day, extreme-but-rare high-temperature events will become common during the summer months. The increasing frequency of extreme heat may affect the health and resiliency of social, biological, and infrastructure systems in many regions worldwide, underscoring the need for accurate and reliable long-term assessments of climatic change across global and regional scales. So far, many investigations of high-temperature extremes have been carried out under end-point scenarios, e.g., by comparing GCM-projected changes in the frequency of high-temperature extremes expected in the late 21st century to the late 20th century. In this study, we use extreme value theory and decades of observations of high-temperature extremes at thousands of meteorological stations across North America to investigate continuous shifts in the frequency of extreme high-temperature events due to projected local warming trends. We find that the odds of exceedance of 50-year extreme high-temperature events increases exponentially with increases in mean local temperature. At a majority of the stations studied here, a local mean temperature increase of 0.5–1 ^{circ }C can double the odds of exceedance of 50-year extreme high-temperature events. Based on time-dependent temperature projections, the odds of exceedance of 50-year extreme high-temperature events doubles approximately every 20 years (or sooner) for sim 96% of the stations. Moreover, we find that, for sim 80% of the stations in North America, investigated here, the 50-year extreme high-temperature events will be exceeded annually before 2100.

Reef building corals show resilience to the hottest marine heatwave on record in the Gulf of Aqaba

Coral reefs are facing rapid deterioration, primarily due to a global rise in seawater temperature. In conjunction, the frequency and intensity of extreme high temperature events, known as marine heatwaves (MHWs), are increasing. The Gulf of Aqaba (GoA) in the northern Red Sea is home to corals known for their thermal resilience, yet concerns have been raised regarding the potential for MHWs to put this coral refuge at risk. In summer of 2021, the hottest MHW so far occurred in the GoA, with sea surface temperatures peaking at 31°C and persisting above the local summer maximum for 34 days. To assess the physiological response of the corals Stylophora pistillata and Pocillopora damicornis to this event, we analyzed the monthly content across a year of host and symbiont proteins, carbohydrates, and lipids, pre-, during, and post the MHW, as a proxy for metabolic stress. We found that the MHW was not fatal to either species and did not induce bleaching, based on algal densities and chlorophyll content. Species-specific responses were detected. In S. pistillata, host protein content decreased (33%) at the onset of the MHW (August) compared to pre-MHW levels (July). Algal symbionts of S. pistillata were unaffected by the MHW in their maximal photosynthetic efficiency (Fv/Fm) and exhibited higher carbohydrate levels (+34%) at the end of the MHW (September) compared to its onset. In contrast, no significant catabolic response was detected in P. damicornis host or symbionts, and the maximal relative electron transport rate (rETRmax) of symbionts was 37% higher during the MHW than the annual average. These results highlight the remarkable ability of common GoA corals to withstand extreme thermal anomalies, underscoring the global significance of this coral refuge.

The 2022 record-breaking high temperature in China: Sub-seasonal stepwise enhanced characteristics, possible causes and its predictability

In the summer of 2022, an unprecedented and long-lasting high temperature swept central-eastern China, causing significant societal effects. However, the sub-seasonal characteristics, causes and predictability of this extreme high temperature event are not well explored. Based on the locations, intensities and causes of the high temperature, we divided it into three stages: early (13 June–3 July), sustained (4–28 July), and enhancement (29 July–30 August) stages. The high temperature during the early stage mainly occurred in north-central China with an anomaly of 2.5 °C compared with climatology (1981–2010), while the last two stages occurred in the middle and lower Yangtze River Basin with anomalies of 2.8 and 3.8 °C respectively. The high temperature during the three stages were all regulated by the strengthening and westward extension of the western Pacific subtropical high (WPSH) but involved different physical process. In the early stage, it was mainly caused by the anticyclones over the Mongolia and Northwest Pacific and enhanced by the minor impact of WPSH. In the sustained stage it was influenced by relatively more stronger WPSH and South Asia high (SAH) and the relatively minor impact of the anticyclone over the north-western South Asia. In the enhancement stage, the high temperature was mainly caused by a combination of the record-breaking WPSH and SAH and the strong European blocking high. Inside, the exceptionally powerful WPSH was well correlated with the sea surface temperature gradient induced by the developing La Niña. The ECMWF and NCEP models reasonably predicted the location and intensity of the high temperature in the early stage, but poorly predicted that in the sustained and enhancement stages partly because of the failure prediction of the WPSH's enhancement and westward extension. The ECMWF model's more accurate prediction of the WPSH may contribute to its better forecasting of the heatwaves.

Middle Eocene Climatic Optimum sensitivity of a continental lake basin from geochemical records of the Fushun Basin, Northeastern China

The dating of continuous Eocene sediments in the Fushun Basin, NE China, provides a good opportunity to study the evolution of the land paleoclimate during extreme high-temperature events in mid-latitude regions. Here, the lower part of the Eocene Xiloutian Formation in the Fushun Basin was sampled, and isotope geochemistry, element geochemistry, organic geochemical analysis, magnetic susceptibility, and sediment color analysis were conducted to determine the evolution of paleoclimate in the continental lake basin during the Middle Eocene Climatic Optimum (MECO) period. The oxygen (δ18O) and carbon (δ13C) isotope data indicated the presence of phases during the MECO, with 401.5–374.3 m (41.2–40.42 Ma) representing the main stage and 374.3–371.2 m (40.42–40.32 Ma) the recovery stage. In addition, evaluation of the opening and closing of lakes using δ18O and δ13C showed that the lakes in the lower part of the Xiloutian Formation in the Fushun Basin are currently in a transition period between open and closed. The reconstructed paleotemperature and precipitation in the lower part of the Xiloutian Formation were characterized by an initial high trend followed by a low trend, with the highest values of both occurring during the main MECO stage. The lower part of the Xiloutian Formation is characterized by an oxidative oxygen environment of brackish water, and MECO events did not affect the salinity and redox state of the water. However, the total organic carbon (average 5.24%) in the dark mudstone during the main MECO stage was significantly higher than that during the cooling period (average 4.67%), indicating that the MECO promoted carbon fixation and enrichment of organic matter. Climate comparison showed that the climatic types in eastern and western regions of China during the Eocene were similar. Furthermore, climatic evolution may be influenced by the uplift of the Tibetan Plateau, and the retreat of the inland proto Paratethys Sea.

Synoptic Atmospheric Patterns Responsible for Summer Extreme High-Temperature Events over Northern Asia: Evolution, Precursor, and Long-Term Change

Abstract In this study, the synoptic atmospheric patterns responsible for regional extreme high-temperature events (REHEs) over northern Asia (NA) are investigated. First, a hybrid regionalization approach is applied to the daily maximum temperature (Tmax), and three subregions of NA can be identified: western NA, central NA, and southeastern NA. To better understand the mechanism for the NA REHE formation, the REHE-related synoptic circulation patterns over each subregion are further categorized into two types. These six synoptic circulation patterns influence the NA REHE occurrence through different radiation and advection processes. Generally, the radiation process dominates the NA REHE occurrence, while the horizontal temperature advection plays a more important role in the synoptic dipole patterns than in the monopole high patterns. The heatwaves associated with the six synoptic patterns can last more than 3.8 days, with a maximum of 2 weeks. From the forecasting perspective, six wave trains are explored as the precursors of these six synoptic circulation patterns, separately. The wave trains originate from the North Atlantic Ocean and Europe with at least a 3-day lead and then propagate eastward to NA, exerting influences on the pronounced six synoptic circulation patterns and consequently affecting the NA REHEs. In terms of long-term change, the REHEs over the three subregions show significant increasing trends over 1960–2018 and significant interdecadal increases around the mid-1990s, in which the contribution of each synoptic pattern–related REHE is different.

The impact of heatwaves on human perceived thermal comfort and thermal resilience potential in urban public open spaces

Climate change increases the likelihood of heatwave events, causing human thermal discomfort and even mortality. However, it is not clear to what extent humans with long-term and short-term experience of hot-summer exposure can adapt to thermal comfort in urban public open spaces when both experience their heatwave periods. Therefore, this study aims to investigate outdoor perceived thermal comfort in urban public open spaces during heatwave periods between two groups of people who have long-term and short-term experience of hot-summer exposure. Field surveys were conducted in public squares and parks during the heatwaves in Chongqing, China and Reading, the UK. Chongqing is known as a ‘furnace city’ and people have been living in a hot summer for a long time, while in Reading the summer is warm and people unusually experience the heatwave. The main results show that Chongqing respondents living in a hot climate for a longer period can endure more heat than Reading respondents during the heatwaves, indicating that Chongqing respondents have more thermal resilience. Besides, different behavioural adaptation measures show that people are active participants to choose their thermal preferences, rather than passive recipients of the thermal environments. The research implication contributes that protective measures against heatwaves need to be taken for pedestrians, including more shaded places with efficient ventilation design for sheltering and handy facilities such as drinking fountains and water spray. The research has novelty in deepening the dynamic theory of human thermal comfort and providing empirical evidence of thermal adaptation in extreme-high temperature events.

Interdecadal Variation of Spring Extreme High-Temperature Events in the Western Tianshan Mountains and Its Relationship with the Tropical SST

This study performed an observational analysis to examine the interdecadal variation in the frequency of extreme high-temperature events (EHEs) during spring over the western Tianshan mountain, China, which were characterized by relatively fewer (more) EHEs during 1983–1996 (2000–2015). A composite analysis indicated that the interdecadal increase in EHEs is closely related to a deep dynamic anomalous Iranian high. Under the control of this high system, the water vapor content decreased over the western Tianshan mountains, and atmospheric circulation was dominated by a descending motion. Both were attributed to the decreased cloud cover, inducing a cloud-forced net solar radiation increase. The short-wave radiation flux and sensible heat flux reaching the surface increased, and the net surface heat flux increased cumulatively, which was conducive to the surface temperature increase and EHE occurrence. The anomalous Iranian high responsible for ECEs occurrence was related to the air-sea interaction over the Atlantic and Indo-Pacific. The latitudinal sea surface temperature (SST) difference between the tropical western Pacific and the western Indian Ocean directly strengthens the Walker circulation and thus enhances the Iranian high. In addition, the anomalous Iranian high was affected by the atmospheric wave trains at middle latitude, which was triggered by the warm anomaly of the Atlantic SST.

Composition and vertical distribution of agricultural soil Macrofauna community after an extreme high temperature event in the summer of 2022

Extreme high temperature (EHT) events are becoming more frequent and prolonged due to global climate change. Predicting the effects of EHT events on agricultural soil fauna remains a major challenge. In order to assess the response of community composition and vertical distribution of soil fauna to EHT events, this study investigated the soil macrofauna communities in facility agricultural farmlands at the end of an EHT event in East China in 2022 and eighteen days after. The results showed that the taxonomic richness and abundances of the soil macrofauna community were reduced eighteen days after the EHT event. However, changes in abundance were taxonomically dependent: individuals of ants (Pheidole indica), centipedes (Himantariidae) and crickets decreased significantly, while Enchytraeidae and earthworms increased. Soil water content was an important factor determining taxonomic richness at the end of the EHT event and the abundance of earthworms eighteen days after the EHT event. The maximum values of taxonomic richness and abundance of the soil macrofauna community were observed in the surface layer (0–10 cm) at the end of the EHT event and eighteen days after. Earthworms burrowed into the deeper layer at the end of the EHT event, but moved to the surface layer eighteen days after the EHT event. These results showed that most soil fauna taxa experienced adverse effects posed by EHT events, while the earthworm and Enchytraeidae had abilities to increase their abundances rapidly by EHT events. This study suggests that soil water content and vertical distribution should be considered when assessing the impact of an EHT event on soil biodiversity.

Decadal variability of extreme high temperature in mid- and high-latitude Asia and its associated North Atlantic air–sea interaction

The decadal variability of extreme high temperature (EHT) in the mid and highlatitudes of continental Asia (MHLCA) and associated mechanisms were investigated. Observational analysis indicated that, after removing global warming, the first leading mode of the EHT events showed a meridional dipole pattern and had significant decadal variability. During the periods 1980–1994 and 2012–2019 (1995–2011), EHT events were more frequent and stronger (less frequent and weaker) in western-central Siberia than normal, whereas they were less frequent and weaker (more frequent and stronger) in the wide area to the south of Lake Baikal. Further Observational and CESM (Community Earth System Model) results based analysis suggested that decadal change in air–sea interaction in the North Atlantic play an important role in shaping the decadal variability of EHT events in MHLCA. On decadal timescales, meridional negative–positive–negative sea surface temperature (SST) anomalies in the North Atlantic and their coupled positive North Atlantic Oscillation can trigger stronger wave activity flux and cause a significant anticyclonic–cyclonic teleconnection wave train in the troposphere over the mid and high latitudes of the Eurasian continent. As a result, an anomalous high-pressure center is evident in western-central Siberia, and thereby reducing total cloud cover and causing stronger solar heating. Thus, EHT events become more frequent and stronger. On the contrary, for the areas south of Lake Baikal, EHT events are weakened by corresponding cyclonic circulation anomalies. Additionally, the CAM5 (Community Atmosphere Model version 5) experiments suggested more important driving role of the decadal North Atlantic tripole SST anomalies in the abovementioned processes.

Exploring the effects of extreme weather events on methane emissions from croplands: A study combining site and global modeling

Croplands, especially rice paddies, are important anthropogenic sources of methane (CH4) emission. Currently, the effects of extreme weather events, which are occurring more frequently with climate warming, on CH4 emissions from croplands still remain uncertain. In this study, we calibrated the CLM5BGCCrop model and implemented it to nine cropland sites and global simulations, in order to a) analyze the spatial and temporal variations of CH4 emissions from different crop and climate types, b) identify corresponding environmental controlling factors, and c) investigate the effects of extreme weather events on CH4 emissions. The results show that parameterized CLM5BGCCrop could simulate CH4 emissions from croplands well at both site and global scales. The simulated CH4 emissions from rice paddies (44.35 Tg CH4 yr−1) are 1–2 orders of magnitude higher than those from corn (0.38 Tg CH4 yr−1) and wheat (2.57 Tg CH4 yr−1) fields. Soil water content is the key factor affecting global CH4 emissions from croplands under present and future climate. Extreme high-temperature events occurring during the rice booting-flowering stage could reduce the CH4 emissions by 28%, while the CH4 emissions could be increased by 12–16% when extreme high-temperature events occurred during the rice milky-maturity stage. Extreme precipitation events increased CH4 emissions by 7% at the rice paddy site. At the global scale, extreme high temperature increased CH4 emissions from rice paddies by 8% at middle latitudes, in contrast, extreme high temperature reduced corresponding emissions by 12% at low latitudes, but the decrease in CH4 emissions from rice paddies at low latitudes will be reversed to a 9% increase in 2081–2100. Overall, the increasing frequency and intensity of extreme weather events in future may lead to increased global CH4 emissions from croplands.

Identification and Characteristics of Historical Extreme High-Temperature Events over the China–Pakistan Economic Corridor

Recently, there has been an increase in the occurrence of extreme high-temperature events across the China–Pakistan Economic Corridor (CPEC). Regional spatiotemporal identification and evaluation of extreme high temperatures are essential for accurate forecasting of future climate changes. When such events generate a meteorological hazard, it is important to understand their temporal and spatial features, return period, and identification criteria. Accurately identifying extreme events can help assess risk and predict their spatial–temporal variation. While past studies have focused on individual sites, extreme heat events generally manifest as spatially and temporally continuous regional events. In this study, we propose an objective identification technique based on gridded data and spatiotemporal continuity to reveal the spatiotemporal characteristics of intensity, frequency, and duration events of extreme heat events in the CPEC from May to October between 1961 and 2015. Furthermore, we estimate the return period of extreme heat in the study region using the generalized Pareto distribution (GPD). Our findings indicate that the historical extreme temperature events (intensity, frequency, and duration) in the CPEC have significantly increased. Areas with a high incidence of extreme heat events are concentrated in eastern Balochistan, northern Sindh, and southeastern Punjab. These findings suggest that disaster prevention and mitigation plans should be targeted towards areas with a high frequency of extreme heat events in the CPEC, allowing policy makers to better prepare for and respond to future events.

Historical and projected changes in Extreme High Temperature events over East Africa and associated with meteorological conditions using CMIP6 models

Historical and projected changes in Extreme High Temperature events over East Africa and associated with meteorological conditions using CMIP6 models