Single Extreme Events Research Articles

Inventory of shallow landslides triggered by extreme precipitation in July 2023 in Beijing, China

The extreme meteorological events caused by climate change have increasingly caused serious clustered landslides. A systematic and timely inventory of triggered landslides is a prerequisite for quantifying and evaluating the impact of extreme meteorological events. In addition, a landslide inventory can provide basic data for any subsequent analysis of the event or be used innovatively in landslide risk analysis. The Rainfall-induced Landslides in Beijing (RLBJ) inventory presented here contains data on 15,383 rainfall-induced shallow landslides triggered by a single extreme precipitation event in July 2023 in an area of ~3,250 km2 in western mountainous areas of Beijing, China. High-resolution satellite images before and after this rainstorm event were used to visually analyze the landslides. All landslides were reported as vectorized points and polygon features and classified according to their motion forms. This inventory is now freely available for the benefit of international geohazard researchers.

The impacts of extreme heat events on non-accidental, cardiovascular, and respiratory mortality: An analysis of 12 Canadian cities from 2000 to 2020.

Extreme heat has significant impacts on mortality. In Canada, past research has analyzed the degree to which non-accidental mortality increases during single extreme heat events; however, few studies have considered multiple causes of death and the impacts of extreme heat events on mortality over longer time periods. Daily death counts attributable to non-accidental, cardiovascular, and respiratory causes were retrieved for the 12 most populous cities in Canada from 2000 to 2020. Generalized additive models were applied to quantify daily mortality risks for people aged younger than 65 years and for those aged 65 years and older in each city and for each cause of death. Model results were used to calculate the change in mortality risks and the number of excess deaths attributable to extreme heat during extreme heat events. Elevated mortality risks were observed during extreme heat events in most cities for non-accidental and respiratory causes. The impacts of extreme heat on non-accidental mortality were typically greater for people aged 65 and older than for those aged younger than 65. Significantly higher non-accidental mortality risks were observed during extreme heat events for people aged 65 and older in Montréal, the city of Québec, Surrey, and Toronto. For cardiovascular and respiratory causes, people aged 65 and older had significantly higher mortality risks during extreme heat events in Montréal, and both Montréal and Toronto, respectively. In the 12 cities, approximately 670 excess non-accidental deaths, 115 excess cardiovascular deaths, and 115 excess respiratory deaths were attributable to extreme heat events during the study period. Mortality risks during extreme heat events were generally higher in cities with larger proportions of renter households and fewer extreme heat events. This study estimates the longer-term impacts of extreme heat events on three mortality outcomes in a set of large Canadian cities. As climate change causes more frequent and intense extreme heat events, and as policy makers aim to reduce the health impacts of heat, it is important to understand how and where extreme heat affects health.

Flash Flood Risk Assessment in the Asir Region, Southwestern Saudi Arabia, Using a Physically-Based Distributed Hydrological Model and GPM IMERG Satellite Rainfall Data

Floods in southwestern Saudi Arabia, especially in the Asir region, are among the major natural disasters caused by natural and human factors. In this region, flash floods that occur in the Wadi Hail Basin greatly affect human life and activities, damaging property, the built environment, infrastructure, landscapes, and facilities. A previous study carried out for the same basin has effectively revealed zones of flood risk using such an approach. However, the utilization of the HEC–HMS (Hydrologic Engineering Center–Hydrologic Modeling System) model and IMERG data for delineating areas prone to flash floods remain unexplored. In response to this advantage, this work primarily focused on flood generation assessment in the Wadi Hail Basin, one of the major basins in the region that is frequently prone to severe flash flood damage, from a single extreme rainfall event. We employed a fully physical-based, distributed hydrological model run with HEC–HMS software version 4.11 and Integrated Multi-satellite Retrievals of Global Precipitation Measurement (IMERG V.06) data, as well as other geo-environmental variables, to simulate the water flow within the Wadi Basin, and predict flash flood hazard. Discharge from the wadi and its sub-basins was predicted using 1 mm rainfall over an 8-h occurrence time. Significant peak discharge (3.6 m3/s) was found in eastern and southern upstream sub-basins and crossing points, rather than those downstream, due to their high-density drainage network (0.12) and CNs (88.4). Generally, four flood hazard levels were identified in the study basin: ‘low risk’, ‘moderate risk’, ‘high risk’, and ‘very high risk’. It was found that 43.8% of the total area of the Wadi Hail Basin is highly prone to flooding. Furthermore, medium- and low-hazard areas make up 4.5–11.2% of the total area, respectively. We found that the peak discharge value of sub-basin 11 (1.8 m3/s) covers 13.2% of the total Wadi Hail area; so, it poses more flood risk than other Wadi Hail sub-basins. The obtained results demonstrated the usefulness of the methods used to develop useful hydrological information in a region lacking ungagged data. This study will play a useful role in identifying the impact of extreme rainfall events on locations that may be susceptible to flash flooding, which will help authorities to develop flood management strategies, particularly in response to extreme events. The study results have potential and valuable policy implications for planners and decision-makers regarding infrastructural development and ensuring environmental stability. The study recommends further research to understand how flash flood hazards correlate with changes at different land use/cover (LULC) classes. This could refine flash flood hazards results and maximize its effectiveness.

Legacy effects of premature defoliation in response to an extreme drought event modulate phytochemical profiles with subtle consequences for leaf herbivory in European beech.

Extreme droughts can have long-lasting effects on forest community dynamics and species interactions. Yet, our understanding of how drought legacy modulates ecological relationships is just unfolding. We tested the hypothesis that leaf chemistry and herbivory show long-term responses to premature defoliation caused by an extreme drought event in European beech (Fagus sylvatica L.). For two consecutive years after the extreme European summer drought in 2018, we collected leaves from the upper and lower canopy of adjacently growing drought-stressed and unstressed trees. Leaf chemistry was analyzed and leaf damage by different herbivore-feeding guilds was quantified. We found thatdrought had lasting impacts on leaf nutrients and on specialized metabolomic profiles. However, drought did not affect the primary metabolome. Drought-related phytochemical changes affected damage of leaf-chewing herbivores whereas damage caused by other herbivore-feeding guilds was largely unaffected. Drought legacy effects on phytochemistry and herbivory were often weaker than between-year or between-canopy strata variability. Our findings suggest that a single extreme drought event bears the potential to long-lastingly affect tree-herbivore interactions. Drought legacy effects likely become more important in modulating tree-herbivore interactions since drought frequency and severity are projected to globally increase in the coming decades.

Can agronomic options alleviate the risk of compound drought-heat events during the wheat flowering period in southeastern Australia?

The impacts of compound drought-heat (DH) events on crops are more devastating than a single extreme event of drought or heat. Previous studies mainly assessed the change of individual extreme climate events. However, studies quantifying the characteristics of DH events during crop growth periods are still lacking. To the best of our knowledge, there is no study that has quantified the potential of adjusting sowing time and changing cultivars to reduce the risk of DH events for wheat in Australia. We aimed to (1) develop a combined index to capture the DH events occurring during the wheat flowering period at six study sites in southeastern Australia’s wheat belt; (2) quantify the changes in the frequency (DHF), duration (DHD), and intensity (DHI) of DH events under future climate; and (3) identify feasible agronomic options to reduce the risk of DH events. We used the APSIM model driven by climate projections from 27 GCMs for the period of 1981–2100 to simulate the wheat flowering time and daily plant available water (PAW) at 0–100 cm soil layer. The wheat sensitive period (WSP) was defined as the period from 2 weeks before flowering to 2 weeks after flowering time. A DH event occurs when the daily maximum temperature is higher than 28 ℃ and daily PAW is less than 40% of plant available water capacity for three consecutive days or more. Then, we assessed the DHF, DHD, and DHI under projected climate change. Finally, we investigated the potential of changing sowing time and cultivars to alleviate DHF, DHD, and DHI under different climate scenarios. According to the average values across six sites, the DHF, DHD, and DHI during the WSP increased by 15%, 12%, and 0.9% in 2040 s, and 49%, 44%, and 5% in 2080 s, respectively, compared to 2000 s. Such increases in DH events were mainly due to enhanced heat events. Early sowing and planting better-performing wheat cultivars with early flowering had great potential to lower the risk of future DH events. They could reduce the DHF, DHD, and DHI by 15%− 100%, 18%− 100%, and 16%− 100%, respectively, compared to without adaptation options. However, the strategy may introduce an increased frost risk across six sites, especially in regions with climates that are less dry and hot, such as Mudgee and Wagga Wagga. We expect our modelling work can provide useful information for developing effective agronomic management practices to help Australian wheat growers better prepare for DH events under climate change. The newly proposed DH framework can be applied to other dryland wheat growing regions globally.

The Frequency of Extreme Cold Events in North China and Their Relationship with Sea Surface Temperature Anomalies

This study investigated the interdecadal characteristics of the frequency of the winter single station extreme cold events (SSECEs) in North China and their relationship with sea surface temperature (SST). The results showed the following: (a) The SSECEs occurred frequently before 1991, but less thereafter, with an increase after 2018. The first two interdecadal modes of the SSECE frequency were east–west inverse and “n” patterns. (b) The interdecadal abrupt change of the “n” pattern occurred around 1997/1998. Before 1997/1998, the synergistic effects between the positive Interdecadal Pacific Oscillation (+IPO) and the negative North Atlantic Multidecadal Oscillation (−AMO) triggered the “two troughs and one ridge” anomalous circulation in Eurasia. The Rossby wave energy propagated downstream from the Atlantic, strengthening the Lake Baikal ridge. Furthermore, the Siberian High (SH) became weaker in the north and stronger in the south. With the favorable jet conditions, the cold air invaded North China along the northerly airflow in front of the Lake Baikal ridge, resulting in the frequent SSECE occurrence in central North China. Afterwards, the opposite occurred. (c) The cooperation of SST anomalies (SSTAs) led to the east–west inverse anomaly of the SSECE frequency. Before 1991, the high SSTAs in the central North Atlantic and low SSTAs in the equatorial Indian Ocean and the southwest Pacific triggered “+”, “−”, “+”, and “−” wave trains at mid-latitudes from the Atlantic to the North Pacific. The Rossby wave energy propagated eastward from the Atlantic, resulting in the SH and Urals ridge strengthening, and the Aleutian Low and East Asian trough deepening. The northwestern airflow in front of the Urals ridge guided the cold air into North China, leading to frequent SSECEs in central and eastern North China before 1991. The opposite occurred between 1992 and 2018.

Compound wind and precipitation extremes at a global scale based on CMIP6 models: Evaluation, projection and uncertainty

AbstractCompound wind and precipitation extremes (CWPEs) amplify risk to human health, socio‐economic and ecological systems relative to their single extreme meteorological events. Given the rise in weather and climate extremes resulting from global warming, it is crucial to evaluate the ability of the Coupled Model Intercomparison Project Phase 6 (CMIP6) models to capture this bivariate compound event and explore projected changes of CWPEs in the future under different climate‐change scenarios—the Shared Socioeconomic Pathway (SSP) scenarios. In this study, we first evaluate 14 CMIP6 models at a global scale using the ERA5 reanalysis data set spanning 1979–2014. Overall, some of the CMIP6 models, especially the multi‐model ensemble mean (MMEM), can reasonably capture CWPEs during the historical period, with more CWPEs in the northern and southern hemispheres during their respective cold seasons. However, the MMEM tends to overestimate CWPEs in some land areas and show underestimation in some oceanic regions. Then we compute projected changes of CWPEs in periods 1 (2041–2070) and 2 (2071–2100) under SSP1‐2.6, SSP2‐4.5 and SSP5‐8.5 scenarios. Low emission scenarios effectively mitigate the long‐term increase in future CWPEs. The occurrence of CWPEs will change significantly with the increase of emissions during period 2, particularly in polar regions. Finally, we quantify the uncertainty for global future projections of CWPE changes. The main sources of uncertainty are internal variability and model uncertainty, but the contribution of scenario uncertainty will increase as time progresses. Overall, our results provide useful information to cope with CWPEs' global impact, emphasizing the importance of incorporating the compound nature of weather and climate extremes in future climate projections.

Analysis of the Composite Risk Grade for Multi Extreme Climate Events in China in Recent 60 Years

Much attention has been given to the change rule of a single extreme event, and there are few reports on comprehensive characteristics of multiple extreme events in a certain region. Based on the analyzes of annual frequency of extreme high temperature, extreme low temperature, extreme drought, extreme precipitation, and extreme typhoon events in China from 1961 to 2020, a multi extreme events composite risk grade index (MXCI) was constructed and applied to the comprehensive characteristics analyzes of multiple extreme events in China. The results show that the high value areas of MXCI were mainly located in southeast China and southwest China. Over the past 60 years, the MXCI has shown a decreasing trend in western China and most of southeastern China, and an increasing trend in the middle zone from southwest China to northeast China. Through comparative analysis, MXCI can objectively reflect the comprehensive characteristics of multiple extreme climate events in a region, which is helpful to understand regional extreme climate characteristics and effectively cope with extreme climate risks.

How the extreme 2019–2020 Australian wildfires affected global circulation and adjustments

Abstract. Wildfires are a significant source of absorbing aerosols in the atmosphere. Extreme fires in particular, such as those during the 2019–2020 Australian wildfire season (Black Summer fires), can have considerable large-scale effects. In this context, the climate impact of extreme wildfires unfolds not only because of the emitted carbon dioxide but also due to smoke aerosol released up to an altitude of 17 km. The overall aerosol effects depend on a variety of factors, such as the amount emitted, the injection height, and the composition of the burned material, and is therefore subject to considerable uncertainty. In the present study, we address the global impact caused by the exceptionally strong and high-reaching smoke emissions from the Australian wildfires using simulations with a global aerosol–climate model. We show that the absorption of solar radiation by the black carbon contained in the emitted smoke led to a shortwave radiative forcing of more than +5 W m−2 in the southern mid-latitudes of the lower stratosphere. Subsequent adjustment processes in the stratosphere slowed down the diabatically driven meridional circulation, thus redistributing the heating perturbation on a global scale. As a result of these stratospheric adjustments, a positive temperature perturbation developed in both hemispheres, leading to additional longwave radiation emitted back to space. According to the model results, this adjustment occurred in the stratosphere within the first 2 months after the event. At the top of the atmosphere (TOA), the net effective radiative forcing (ERF) averaged over the Southern Hemisphere was initially dominated by the instantaneous positive radiative forcing of about +0.5 W m−2, for which the positive sign resulted mainly from the presence of clouds above the Southern Ocean. The longwave adjustments led to a compensation of the initially net positive TOA ERF, which is seen in the Southern Hemisphere, the tropics, and the northern mid-latitudes. The simulated changes in the lower stratosphere also affected the upper troposphere through a thermodynamic downward coupling. Subsequently, increased temperatures were also obtained in the upper troposphere, causing a global decrease in relative humidity, cirrus amount, and the ice water path of about 0.2 %. As a result, surface precipitation also decreased by a similar amount, which was accompanied by a weakening of the tropospheric circulation due to the given energetic constraints. In general, it appears that the radiative effects of smoke from single extreme wildfire events can lead to global impacts that affect the interplay of tropospheric and stratospheric budgets in complex ways. This emphasizes that future changes in extreme wildfires need to be included in projections of aerosol radiative forcing.

Compound flood events: analysing the joint occurrence of extreme river discharge events and storm surges in northern and central Europe

Abstract. The simultaneous occurrence of extreme events gained more and more attention from scientific research in the last couple of years. Compared to the occurrence of single extreme events, co-occurring or compound extremes may substantially increase risks. To adequately address such risks, improving our understanding of compound flood events in Europe is necessary and requires reliable estimates of their probability of occurrence together with potential future changes. In this study compound flood events in northern and central Europe were studied using a Monte Carlo-based approach that avoids the use of copulas. Second, we investigate if the number of observed compound extreme events is within the expected range of 2 standard deviations of randomly occurring compound events. This includes variations of several parameters to test the stability of the identified patterns. Finally, we analyse if the observed compound extreme events had a common large-scale meteorological driver. The results of our investigation show that rivers along the west-facing coasts of Europe experienced a higher amount of compound flood events than expected by pure chance. In these regions, the vast majority of the observed compound flood events seem to be related to the cyclonic westerly general weather pattern (Großwetterlage).

Analysing the Large-Scale Debris Flow Event in July 2022 in Horlachtal, Austria Using Remote Sensing and Measurement Data

High-quality in situ measurements are essential for hazard assessment of debris flow events. However, precise data on debris flow triggering thresholds, accumulation volumes and spatial characteristics of large-scale events on catchment scale are scarce due to the rare occurrence of debris flows and the challenges of acquiring accurate data for a larger area. In this study, we present quantitative analyses of a single extreme debris flow event in the Horlachtal, Austria, triggered by local high-intensity short-duration precipitation events on 20 and 23 July 2022. Pre- and post-event airborne LiDAR (light detection and ranging) data with a high spatial resolution reveal that 156 different debris flow processes were initiated during these events, with accumulation volumes of up to approximately 40,000 m³. The calculated debris flow deposition volumes also show a power-law relationship with the total amount of rainfall in the respective debris flow catchments. The spatial appearance of the debris flows shows a concentration of processes in a particular area rather than a uniform distribution, suggesting a local nature of the triggering event. This is further supported by the measurements from three meteorological stations and four discharge gauges within the study area. The gridded area-wide INCA (Integrated Nowcasting through Comprehensive Analysis) rainfall data further point to a local convective event on 20 July 2022, with a maximum rainfall intensity of 44 mm/h.

Compound and successive events of extreme precipitation and extreme runoff under heatwaves based on CMIP6 models

Global warming accelerates the rate of interregional hydrological cycles, thus leading to a significant increase in the frequency and intensity of global extreme events. An extreme event that causes other extreme events within a short period of time is a successive event. Compound and successive extreme events are more harmful than single extreme events. Therefore, this study revealed the evolution characteristics of compound heatwave and extreme precipitation/runoff events (CHP/CHR), successive heatwave and extreme precipitation/runoff events (SHP/SHR). The population exposure of the four compound events was assessed in the future. The results are as follows: (1) the frequencies of CHP, CHR, SHP, and SHR have all shown a significant upward trend since the Industrial Revolution, especially at low and high latitudes. Under the future SSP585 scenario, CHP and CHR had the largest change rates from 2065 to 2099 at 2.01 events/decade and 1.86 events/decade, respectively. (2) The proportion of severe and extreme events increased significantly in various regions from 1970 to 2014. SHP and SHR have the largest proportion of severe/extreme events in 2015–2039/2065–2099. (3) The CHP and CHR changes in the historical period mainly occurred at high latitudes, while SHP and SHR had the largest change rates in low latitudes. The temperature was dominant compound and successive events in the future. The intensity of the compound event was much larger than that of its corresponding successive event under the high-emission scenario. (4) Climate effect had the most obvious impact on the change of population exposure. Compared with the SSP126 scenario, the population exposure change of the compound event increased by 3.1 times and 3.2 times under the SSP585 scenario during 2065–2099 and 2015–2039, respectively.

Resilience of ecosystem service delivery in grasslands in response to single and compound extreme weather events

Extreme weather events are increasing in frequency and magnitude with profound effects on ecosystem functioning. Further, there is now a greater likelihood that multiple extreme events are occurring within a single year. Here we investigated the effect of a single drought, flood or compound (flood + drought) extreme event on temperate grassland ecosystem processes in a field experiment. To assess system resistance and resilience, we studied changes in a wide range of above- and below-ground indicators (plant diversity and productivity, greenhouse gas emissions, soil chemical, physical and biological metrics) during the 8 week stress events and then for 2 years post-stress. We hypothesized that agricultural grasslands would have different degrees of resistance and resilience to flood and drought stress. We also investigated two alternative hypotheses that the combined flood + drought treatment would either, (A) promote ecosystem resilience through more rapid recovery of soil moisture conditions or (B) exacerbate the impact of the single flood or drought event. Our results showed that flooding had a much greater effect than drought on ecosystem processes and that the grassland was more resistant and resilient to drought than to flood. The immediate impact of flooding on all indicators was negative, especially for those related to production, and climate and water regulation. Flooding stress caused pronounced and persistent shifts in soil microbial and plant communities with large implications for nutrient cycling and long-term ecosystem function. The compound flood + drought treatment failed to show a more severe impact than the single extreme events. Rather, there was an indication of quicker recovery of soil and microbial parameters suggesting greater resilience in line with hypothesis (A). This study clearly reveals that contrasting extreme weather events differentially affect grassland ecosystem function but that concurrent events of a contrasting nature may promote ecosystem resilience to future stress.

The Grid Under Extremes: Pandemic Impacts on California Electricity Consumption

When confronted with crises and other extreme events, the core responsibility of the grid does not change: to meet society’s demand for electricity in a safe and reliable manner. However, these extreme events are now interacting with a transitioning grid system that is constantly evolving and adapting to meet new societal needs. This change includes the decarbonization of energy systems while also ensuring equity in its reliability, accessibility, and affordability of energy for all. In this article, we examine a single extreme event with unprecedented impacts on the energy system: the COVID-19 pandemic. Using California as an example, we explore in detail the pandemic-related impacts on electricity consumption and make recommendations for improving planning, forecasting, and other operations in response to extremes.

Early snowmelt by an extreme warming event affects understory more than overstory trees in Japanese temperate forests

AbstractThe occurrence of extreme warm events and early snowmelt is predicted to increase in high‐latitude ecosystems, even during periods of time when there is no coincident reduction in total precipitation. However, because extreme events like these occur unpredictably, little is known about how advancing snowmelt by a single extreme warm event, without a reduction in precipitation amount, influences overstory trees and understory vegetation simultaneously in an ecosystem. We conducted a warming experiment (four 20 × 20 m plots) in temperate forests of Japan to determine the effects of earlier snowmelt on both understory dwarf bamboo plants and overstory birch trees. Our experimental treatment advanced snowmelt by about 10 days and increased soil temperatures that were associated with increased rates of soil nitrogen (N) mineralization and nitrification. Furthermore, these changes led to lower C:N ratios of leaves together with the greater growth of understory bamboo vegetation, with no changes in leaf C:N or growth rates of overstory birch trees. Together, our results demonstrate that advancing snowmelt by an extreme warm event in temperate forests is likely to affect N cycling and will benefit understory vegetation without a commensurate change in overstory vegetation, likely due to the increase in available soil N. These results also demonstrate that with the projected increase in the frequency of extreme warm events and advanced snowmelt, understory vegetation is likely to benefit more than overstory trees in Japanese temperate forests with heavy snow.

Increased Compound Droughts and Heatwaves in a Double Pack in Central Asia

Compound droughts and heatwaves (CDHWs) are likely to cause more severe natural disasters than a single extreme event, and they have been exacerbated by rapid global warming. Based on high-resolution grid data, this study combines the daily-scale ERA5-Land dataset and the monthly-scale SPEI dataset with multiple indicators to analyze CDHWs. We calculated and analyzed the temporal and spatial modal distribution of CDHWs in Central Asia from 1981 to 2018, and in this paper, we discuss the sequence relationship between drought events, heatwave events, and CDHWs. The results show that the number of CDHWs in the study region have increased over time and expanded in terms of area, especially in eastern and southwestern Central Asia. The tsum (total frequency of CDHWs) was 0.5 times higher than the total heatwave frequency and it increased at a rate of 0.17/yr. The maximum duration of tmax (maximum duration of CDHWs in days) was 17 days. Furthermore, the occurrence rate of tmax was 96.67%, and the AH (CDHWs’ accumulated heat) had a rate of 97.78%, which, upon examination of the spatial trend pattern, accounted for the largest increase in terms of area. We also found that the TAH (CDHWs’ average temperature anomalies, SPEI < −0.5) shows obvious seasonality, with the increases in winter and spring being significantly greater than the increases in summer and autumn. The intensity of the CDHWs was stronger than that of a single extreme event, the temperature anomaly was higher than the average of 0.4–0.8 °C, and there was a north–south spatial pattern across the study region. In eastern and northwestern Central Asia, the AH and heatwaves (SPEI < −0.5) increased by 15–30 times per year on average. During the transition from the base period to the reference period, CDHWs increased by 25%, and the number of dry days prior to the CDHWs decreased by 7.35 days. The conclusion of our study can provide a theoretical basis for coping with climate change in arid zones.

Growing prevalence of heat over cold extremes with overall milder extremes and multiple successive events

Temperature extremes with altered characteristics are one of the most threatening impacts of global warming. How their characteristics have changed is uncertain, and varies by region. Here we analyse ERA5 reanalysis data for the period 1980 to 2018 to illuminate the spatio-temporal characteristics of single and multiple successive temperature extreme events at the global scale. We show that in the global average, the magnitude of heat extremes significantly increased while that of cold extremes decreased at a faster rate. As a result, the prevailing climate shifted from a prevalence of cold extremes to one of heat extremes, and the overall magnitude of extremes decreased. Globally, the magnitude of multiple successive temperature extreme events constituted about a quarter of all identified events. These trends were not globally uniform. The most noteworthy trends were observed in the Tropical and Polar zones; the Middle East and North Africa, including the Mediterranean region, were identified as hotspots of climate shifts.

Ethics of Probabilistic Extreme Event Attribution in Climate Change Science: A Critique

AbstractThe question whether a single extreme climate event, such as a hurricane or heatwave, can be attributed to human induced climate change has become a vibrant field of research and discussion in recent years. Proponents of the most common approach (probabilistic event attribution) argue for using single event attribution for advancing climate policy, not least in the context of loss and damages, while critics are raising concerns about inductive risks which may result in misguided policies. Here, we present six ethical predicaments, rooted in epistemic choices of single event attribution for policy making, with a focus on problems related to loss and damage. Our results show that probabilistic event attribution is particularly sensitive to these predicaments, rendering the choice of method value laden and hence political. Our review shows how the putatively apolitical approach becomes political and deeply problematic from a climate justice perspective. We also suggest that extreme event attribution (EEA) is becoming more and more irrelevant for projecting loss and damages as socio‐ecological systems are increasingly destabilized by climate change. We conclude by suggesting a more causality driven approach for understanding loss and damage, that is, less prone to the ethical predicaments of EEA.

Identifying agricultural disaster risk zones for future climate actions.

Identifying agricultural disaster risk regions before the occurrence of climate-related disasters is critical for early mitigation planning. This paper aims to identify these regions based on data from the Food and Agriculture Organization of the United Nations (FAO), the bilateral and multilateral trade network data of the World Integrated Trade Solution(WITS) and the agent-based economic model Acclimate. By applying a uniform forcing across agricultural sectors of some breadbasket regions (US, EU and China), when single and simultaneous extreme weather events occur, such as the 2018 European heatwave, production and consumption value losses and gains are calculated at regional and global levels. Comparing the FAO data sets, WITS, and Acclimate's production value losses, the results show a strong dependence of agricultural production losses on a region's output and connectivity level in the global supply and trade network. While India, Brazil, Russia, Canada, Australia, and Iran are highly vulnerable, the imposition of export restrictions to compensate for demand shortfalls makes Sub-Saharan Africa the most vulnerable region, as it is heavily dependent on agricultural imports. In addition, simultaneous extreme weather events can exacerbate the loss of value of agricultural production relative to single extreme weather events. Agricultural practices to increase production such as smart farming, increased investment in plantation agriculture, and diversification of trading partners can help mitigate future food security risks in Sub-Saharan Africa and other agricultural import-dependent regions.

The Effects of Climate Change on Child and Adolescent Mental Health: Clinical Considerations.

We review recent literature on the effects of climate change on child and adolescent mental health and discuss treatment and engagement by clinicians. Climate change affects child and adolescent mental health in many intersecting ways, including as a social and ecological determinant of health, a threat amplifier, and a source of trauma and distress. Single extreme weather events contribute to significant negative mental health consequences; however, subacute and chronic climate events also have mental health sequelae. Furthermore, awareness of the climate crisis is associated with emotional distress. Young people with pre-existing mental illness and lacking social support may be at elevated risk for climate change-related mental health effects. Climate activism is associated with resilience and positive development, but may also be a source of increased stress, particularly for marginalized youths. Climate change can affect the mental health of children and adolescents in complex and diverse ways. Sources of coping and resilience also vary greatly between individuals. Mental health clinicians must respond to this existential crisis by addressing research gaps in this area, obtaining relevant clinical training, educating their communities, and joining and supporting young people in their advocacy efforts.