We calculate the hourly wet bulb globe temperature (WBGT) values for the last 50 years over Western Africa to assess the emergence of new heatwave hotspots and the interplay between moist and dry heatwaves. In the formulation used, WBGT is derived using the grided data from ERA5 and ERA5-HEAT: 2-m air temperature, relative humidity, 10-m wind speed and mean radiant temperature (a measure of incidence of radiation on a body), and is thus representative of outdoor conditions.

We find that the heat stress estimated through WBGT does not peak over the same geographical regions as the air temperature, suggesting an important role of humidity in intensifying heatwaves over certain regions. While the highest temperatures are reached in the northern Sahel and Saharan regions, the highest heat stress values are found further to the south, in the region bordering Senegal, Mauritania and Mali and in southwest Niger. These are the same regions where the WBGT threshold of 33 °C (conditions dangerous even at resting metabolic rates (MR) < 115 W) have recently been crossed for up to 40 hours per year.

The duration of exposure to WBGT > 30 °C (conditions dangerous at light physical activity, MR < 180 W) has been increasing over almost the entire West Africa, at rates from 30 to 100 hours/decade. Over the Senegal - Mauritania - Mali border and southern Niger, exposure to WBGT > 33 °C has been increasing by 1-4 hours/decade.

Dangerous WBGT thresholds can be crossed at a wide range of temperatures and are often not associated with the highest temperature percentiles. For example, in Niamey, a WBGT of 30 °C has been crossed in the temperature range from ~ 29 to 44 °C, in Thies (Dakar) and Ouagadougou from ~ 28 to 43 °C, and in Abidjan from ~ 28 - 36 °C.  In September 2019 and July 2020, in Niamey we find the first occurrences of air temperatures below 36 °C being associated with very dangerous heat stress values (WBGT > 33 ° C).

We conclude that for much of continental West Africa, and particularly for the Senegal - Mauritania - Mali border region and southern Niger, extreme heat alerts should at a minimum include indicators accounting for temperature and humidity, in order to capture the dangerous moist heatwave conditions occurring at temperatures well below the highest temperature percentiles. More complex indicators that additionally account for wind and radiation are very desirable for estimates of outdoor safety.

How to cite: Cvijanovic, I., Sultan, B., Mbengue, A., and Lavaysse, C.: Emergence of new heat stress hotspots over the West Africa, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3128, https://doi.org/10.5194/egusphere-egu25-3128, 2025.

Temperature rise, amplified by climate change, has a direct impact on human health, exacerbating the risk of heat-related illnesses, such as heat stroke and dehydration. The ((HI) is a parameter that combines air temperature and relative humidity to assess the degree to which the human body perceives heat. In this study, we used the Steadman Man-Kendall HI equation, Sen's slope estimator to evaluate monthly and annual heat index trends for Kano and Bamako between 1992 and 2022. The results indicated that the heat index exhibited a positive trend of 0.01°C yr^-1, although this trend was less statistically significant with a p-value greater than 0.05. In contrast, a significant negative trend was observed in Bamako, with an annual change of approximately -0.06°C yr^-1. It was also observed that the highest heat index values, demonstrating the risk of heat exhaustion, were recorded between April and May, ranging from 30 and 41°C in Kano and 31 to 42°C in Bamako. In contrast, December, January, and February were the coolest months for both cities, with HI values ranging from 23 °C to 28°C in Kano and 25 °C to 28°C in Bamako. These findings underscore the need for policymakers to adopt adaptive strategies to address the health challenges posed by the extreme Heat Index in vulnerable regions.

How to cite: Dicko, K., Umaru, E. T., Sanogo, S., Loewner, R., and Okhimamhe, A. A.: Assessing changes in heat index associated with climate variability in Sahelian Cities, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12625, https://doi.org/10.5194/egusphere-egu25-12625, 2025.

The increase of heatwaves has been observed due to the influence of a changing climate on the planet. Among populations, this phenomenon is associated with a rise in various types of cardiovascular diseases, particularly among vulnerable groups such as the elderly and individuals with pre-existing conditions. This presents a growing concern for healthcare systems and urban management. Although the literature predominantly highlights these events on the European continent, it is known that heatwaves are not confined to this region. Thus, the objective of this study is to evaluate the temporal evolution of the phenomenon through an index developed by LAMMOC/UFF to detect extreme heatwaves in the 26 Brazilian capitals and the Federal District. For this purpose, ERA5 reanalysis data from January 1950 to September 2024 were utilized. The index was calculated hourly and aggregated on a daily and monthly basis. Initially, the Mann-Kendall test was employed to assess the trends in the time series. It was observed that 19 of the analyzed cities exhibited a positive trend, two showed no trend (Florianópolis and Fortaleza), and six coastal cities (primarily in northeastern region, except for Teresina and Recife) located in a region with barotropic conditions did not show occurrences of extreme heat waves during the study period. Subsequently, a correlation matrix between the time series was analyzed, along with clustering, identifying three distinct groups: one less affected by extreme heat waves, a second intermediate group with a positive trend, and a third group that exhibited the most significant positive trends. The time series were then divided, applying a clustering technique, into three distinct periods: 1950–1974 (P1), 1975–1999 (P2), and 2000–2024 (P3). This allowed the calculation of the average accumulated values for these three periods across all evaluated cities to observe the percentage differences. For instance, from P1 to P3, in the southeastern region, the cities of Rio de Janeiro and São Paulo presented an approximate 613% and 643% increase in extreme heatwave occurrences, while in the south region, Porto Alegre had an increase of 557%. In the midwest, Campo Grande and Cuiabá presented an increase of 983% and 671% and in the northeast Recife and Teresina presented an increase of 217% and 257%. Furthermore, the third cluster displayed the highest trends and averages, encompassing most cities of the Northern region. Therefore, cities such as Macapá, Rio Branco, Manaus and Belém experienced an increase of  3154%, 1339%, 1100% and 1028%, respectively. Notably, it was observed that this third cluster predominantly comprised cities in the northern region of the country, situated within the Amazon biome. These findings call for further investigation into the relationship between this trend and factors such as increasing deforestation and forest fires in the region. These alarming results highlight the urgent challenges in environmental, healthcare, and urban management driven by climate change and extreme events, emphasizing the need for investments in municipal health, resilience, and climate mitigation and adaptation strategies.

How to cite: Galves, V. L., Cataldi, M., Alcoforado Sphaier, L., and da Fonseca Aguiar, L.: Temporal Evolution and Intensification of Extreme Heatwaves in Brazil’s capitals: Insights from the XHW Index (1950–2024), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12454, https://doi.org/10.5194/egusphere-egu25-12454, 2025.

Since the early 2000s, Spain has experienced a consistent increase in the frequency and severity of heatwaves. Studies indicate that the number of days with extreme heat summer temperatures has increased, particularly in regions such as Andalusia, Valencia, and Madrid. The 2003 heatwave, regarded as a pivotal event in Europe, resulted in over 70,000 additional deaths across European countries, with Spain contributing almost 20% to this statistic (approximately 13,000 deaths). Further studies emphasise that extreme heatwave events, like the 2003 episode, are no longer exceptional phenomena but are becoming recurrent, even in areas where such events were rare before 1980. These extreme heatwave episodes can pose a serious risk to human health, even leading to severe heat illnesses such as heatstroke, hyperthermia, and critical dehydration. Furthermore, they can also exacerbate pre-existing pathologies like cardiovascular and respiratory diseases. This results in a substantial increase in hospitalisations and even fatalities. This study aims to employ a novel Extreme Heatwave (XHW) characterization index, based on the human body's response to water loss during such events, to evaluate the temporal evolution of these occurrences across Spain, with a special focus on the 13 most populated cities (> 300,000 inhabitants). The analysis utilised ERA5 reanalysis (~25 km resolution) for the period 1950–2024. The results showed that, through the application of a k-means clustering technique, XHW occurrences in Spain could be categorised into three distinct periods: 1950–1977 (P1), 1978–2002 (P2), and 2003–2024 (P3). For this assessment, the daily XHW index values were accumulated monthly and then annually at each grid point of the reanalysis data subsequently interpolated using Bilinear Interpolation for the 13 Spanish cities. The highest percentage increases in cumulative XHW index values were observed in Andalusia, exceeding 1000% in certain grid points when comparing the sums of P3 and P1. Some regions and cities, such as Madrid and Barcelona, experienced virtually no XHW episodes during P1, but these became relatively frequent (in over 80% of the years) during P3. In certain cities and regions, particularly in the Southwest of the country, it was found that during P3, one in every four summer days, on average, presented an XHW index value greater than zero. The results revealed and quantified an alarming scenario regarding the increased intensity and frequency of XHW episodes in Spain. This trend is compounded by the broader context of climate change, which coincides with the warming of the North Atlantic Ocean near the western coast of the Iberian Peninsula and the Mediterranean Sea along the remaining coastal regions of the country. Such developments are likely to exacerbate this situation further in the coming years, potentially precipitating a severe crisis in the Spanish public healthcare system. 

How to cite: Cataldi, M., Victalino Galves, V. L., Alcoforado Sphaier, L., and Garnés-Morales, G.: Quantifying the Escalation of Heatwave Events in Spain: A Study Based on the new XHW Index, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12585, https://doi.org/10.5194/egusphere-egu25-12585, 2025.

The West African Sahel has suffered an unprecedented hot season in the first half of 2024. This preliminary observational study characterises this extreme heat in the urban context of Ouagadougou, one of the major cities in the region where significant death casualty was reported. Using data from the national meteorological agency and the European reanalysis (ERA5), the study investigated both the daytime (Tmax) and nighttime temperatures (Tmin) with the 1991-2020 as reference period. The results show that the average monthly Tmax anomaly ranged from 1.42 °C in January 2024 to 2.41 °C in June 2024, versus -0.4 °C in  January 2024 and 2.05 °C in June 2024 for Tmin, showing that the heat was more important in 2024 than in the historical period. Using the heat wave definition of the Burkina Faso Red Cross heat wave early action protocol, a total of four (one) daytime (nighttime) heat waves were recorded in the city between March and May. This is to be compared with a historical frequency of one event every four years. The longest daytime heat lasted six days with Tmax reaching a maximum of 44.5°C. The unique nighttime heat wave was twice as long as the longest daytime heat wave, persisting for 13 days between late April and early May, a record in the city. From a spatial perspective, the heat was not evenly distributed as some neighbourhoods were significantly hotter than the rest of the city. Furthermore, the initial findings of a household survey conducted in the city corroborated the unprecedentedness of the situation as most respondents reported having never experienced such heat levels in the past with considerable impacts on their health and livelihoods. These results underscore the need for more efforts towards heat wave risk management in African cities.

How to cite: Wendkuni Ghislain, N., Kiswendsida H., G., Dazangwende E., P., and Thomas R., B.: Identification and characterization of 2024 Heat waves in Burkina Faso., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-817, https://doi.org/10.5194/egusphere-egu25-817, 2025.

How to cite: Carniel, C. E., Wille, J. D., and Fischer, E.: Higher coastal heat stress maxima in storm-resolving GCMs, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8553, https://doi.org/10.5194/egusphere-egu25-8553, 2025.

As climate change intensifies, heat extremes pose an increasing threat to human health, leading to heightened morbidity and mortality particularly among vulnerable populations.

Physiological evidence demonstrates that high humidity exacerbates heat strain by impairing the body’s ability to thermoregulate through sweat evaporation. Therefore, metrics such as the wet bulb temperature, which combine both temperature and humidity effects, are commonly used to assess heat-related health risks, highlighting tropical and other humid regions as particularly at risk, while regions dominated by dry heat in the mid-to high latitudes appear comparatively less affected.

However, the tens of thousands of excess deaths caused by prolonged exposure to high ambient temperatures during e.g. recent record-breaking European heatwaves in 2003 and 2022 suggest that heatwave characteristics beyond temperature and humidity might need to be accounted for to accurately capture severe health impacts under dry heat conditions.

Here, we propose to enhance global heat stress assessments by addressing emerging spatio-temporally compounding features of heat extremes, which could greatly aggravate health impacts but due to their complexity are often not considered. Preliminary results will be presented from our efforts to develop a standardized, impact-focused heat stress metric that provides more robust and consistent assessments across diverse regional and climatic settings by integrating the cumulative effects of prolonged and sequential heat exposure.

How to cite: Langer, R. and Kornhuber, K.: Towards Improved Global Heat Stress Projections by Accounting for Spatio-Temporally Compounding Risks, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19232, https://doi.org/10.5194/egusphere-egu25-19232, 2025.

Humid heat is a serious risk to human health, reducing the body’s ability to cool through sweating. The intensity, frequency and impact of humid heat extremes will increase under climate change, particularly in tropical and sub-tropical ‘hot spots’, such as equatorial Africa and the Indian subcontinent, which are highly populated, and already very hot and humid. Research on the meteorological drivers of humid heat extremes is immature compared to that for dry heatwaves. Here an overview of the latest results from the Humid heat extremes in the Global (Sub)Tropics (H2X) project will be presented. We have shown that rainfall is a key ingredient for humid heat, and its role varies depending on the type of land-atmosphere coupling regime. In moisture-limited environments, mostly in the semi-arid sub-tropics, humid heat extremes occur during or immediately after rainfall through increased evaporation into a shallower boundary layer. In energy-limited environments, mostly in the moist tropics, humid heat extremes occur during the easing of rainfall through increased solar heating. Our most recent work focuses on atmospheric waves as a source of predictability. Equatorial Kelvin waves modulate humid heat, where the convergent phase of the wave (in the 850hPa winds) brings rainfall, followed by increased solar heating in the divergent phase. A similar process occurs over the Sahel region of west Africa within African Easterly Waves. We have also performed a set of idealised experiments with the Met Office Unified Model to quantify the role of surface moisture sources such as lakes, wetlands, and patches of wet soil from rainfall on evaporation, mesoscale circulations, and humid heat. Our results are valuable for identifying processes that must be well represented in weather and climate models for accurate weather forecasts and climate projections, and for informing early warning system development.

How to cite: Birch, C., Jackson, L., Chagnaud, G., Hidayat, A., Taylor, C., Law, J., and Marsham, J.: Meteorological drivers of humid heat extremes across the global (sub)tropics, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5617, https://doi.org/10.5194/egusphere-egu25-5617, 2025.

Compound hazards, such as the sequential occurrence of Tropical Cyclones (TC) and humid heatwaves in close succession, are more destructive than individual and isolated occurrences of each hazard. While landfalling TCs cause catastrophic consequences from storm surges, strong winds, heavy rain, and pluvial flooding, they are often compounded by anomalous heat. The TC-heat joint occurrence raises significant concerns for public health and critical infrastructure, particularly since powerful TCs may lead to major power outages. For example, TC Remal in May 2024 damaged the coastlines of India and Bangladesh, bordering the Bay of Bengal (BoB), impacting > 10 million people without access to electricity and shelter, with an estimated damage totaling $600 million. For the eastern coast of India, with many small to large port cities, including two major urban agglomerates, Kolkata and Chennai, with populations > 10 million, the likelihood of TC-heat joint occurrence has not been assessed so far. We analyze 251 landfalling TCs on the eastern coast of India between 1982 and 2023. We show that ~16% of terrestrial humid heatwave peaks are compounded by the landfalling TCs, and ~8% of moist heat follows TCs. Further, we show the relative increase in peak wet-bulb temperature in TC-compounded heatwaves is as high as around 7−10% in pre-monsoon (April−May) and post-monsoon (October−December) seasons compared to heatwaves not compounded by the TCs. An anomalous rise in TC-compounded heatwave peaks is more pronounced and often exceeds terrestrial heatwave peaks during the post-monsoon season. Although the annual counts of landfalling TCs over BoB show a decreasing trend, our observational analysis of precursor coincidence rate confirms the increased likelihood of TC-compounded humid heat stress, preconditioned by strong to severe marine heat waves. The derived insights highlight a need to prepare adaptation planning for unprecedented compound tropical cyclones and extreme heat hazards when such sequential hazards are expected to occur more frequently in a warming climate. 

How to cite: Ganguli, P. and Lin, N.: Mapping Compound Hazard Potential of Tropical Cyclone and Anomalous Heat in Eastern Coast of India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-215, https://doi.org/10.5194/egusphere-egu25-215, 2025.

According to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment (AR6) report, continued global warming and changes in the climate system will increase the likelihood of severe impacts on both people and ecosystems. Accurately assessing the impacts of extreme heat has become a pressing research challenge, particularly as heatwave and heat-health warning systems evolve. Identifying key indicators of heat-related mortality and morbidity is critical to mitigating these impacts. Despite its importance, a comprehensive national-level assessment of heat vulnerability in India remains underdeveloped, leaving a significant research gap in heatwave disaster management. Moreover, the notion of vulnerability has evolved continuously, especially with updates in IPCC assessments, and it varies across communities, societies, regions, and countries and changes over time. This study analyses district-level (640 districts) vulnerability in India based on multiple methodologies, including the Simple Average Method, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), the Principal Component 1 (PC1) method, and the Cutter and Finch (2008) approach, supported by a refined set of vulnerability indicators. Key data sources include the Census of India (CoI), alongside other datasets. The spatial distribution of vulnerability indicates that North and Eastern India are the most susceptible to heat related vulnerability. In the context of India’s agrarian economy, this mapping is crucial for supporting the livelihoods of farmers and outdoor workers, who are among the most susceptible to extreme heat events. This study underscores the urgent need for a robust, methodologically comprehensive national heat vulnerability assessment to guide targeted policy interventions and enhance resilience against the escalating threat of extreme heat in India. The vulnerability map developed will serve as a foundational tool for creating a comprehensive risk map by integrating hazard and exposure, enabling targeted interventions to mitigate heat-related risks.  

Keywords: Heatwave, Heat Stress, India, IPCC, Vulnerability.

How to cite: Shilin, A. and Karmakar, S.: Unveiling Heat Vulnerability Across India: A Multi-Method Analysis of District-Level Indicators in the Context of Climate Change., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10921, https://doi.org/10.5194/egusphere-egu25-10921, 2025.

Heatwaves have become more frequent and more intense under the influence of climate change, resulting in increased impacts on human health, infrastructure and economic activities. However, heatwaves climatic characteristics do not always inform properly on the actual human and material impacts resulting from heatwaves. In other terms, heatwaves with a high intensity in the climatological sense may not be equivalently as intense in terms of impacts. In this study, we empirically investigate, in Europe, the link between the climatic characteristics of heatwaves and their impacts, as listed in the EM-DAT disaster database. We apply indices available in the literature to characterize heatwaves for the 1950-2021 period found in the ERA5 and E-OBS datasets. We also propose new indices, combining meteorological and demographic data, that we compare to the existing ones, and to the heatwave’s impacts. We show that including demographic data in the heatwaves indices is key to ensure that heatwave climatic indices reflect more accurately the impacts of heatwaves. We also investigate the top 10 heatwaves that are considered extreme based on our best performing index but are not in the impact data-base and find references of their impacts for 8 of them, meaning that this type of methodology could be used to enrich existing impact databases by flagging events of interest.

How to cite: Mandonnet, L., Jézéquel, A., D'Andrea, F., and Vallet, A.: Extreme heatwaves in Europe 1950-2021: analysis of the links between meteorology, population, and impacts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3676, https://doi.org/10.5194/egusphere-egu25-3676, 2025.

Countless heat records were broken in recent years, leading to thousands of heat-related deaths. This raises the question of how much worse heat-related mortality could become in coming years if a potential worst-case heatwave lasts for several weeks or reaches unprecedented intensity. Here, we develop impact storylines for worst-case heatwaves and associated heat-related mortality in France, Germany, and Switzerland. 

We compare several physical climate storyline approaches to quantify plausible extreme heatwaves and combine these with empirical heat-mortality relationships. The storylines are based on (a) using a Single-Model Initial Condition Large Ensemble (SMILE), (b) ensemble boosting, and by looking for the most extreme events (UNSEEN approach) in the initialized (c) 45-day sub-seasonal re-forecast and (d) 7-months seasonal forecasting system using the ECMWF Integrated Forecast System (IFS).

In all four approaches we find physically consistent week-long heatwaves possible in the climate of 2020 that exceed the observed 7-day record temperatures by more than 5°C and associated mortality impacts exceeding the observed maximum by 30-90%. Even more severe consequences would arise from possible five-week heat periods of unprecedented intensity, which would lead to more than a doubling of impacts. Developing these impact storylines can inform the stress-testing of socio-economic systems for preparing appropriate emergency response capacities.

How to cite: Vicedo Cabrera, A. M., Luthi, S., Huber, V., Pascal, M., Beyerle, U., Pyrina, M., Domeisen, D., and Fischer, E.: Storylines for month-long heatwaves and associated heat-related mortality impacts over Western Europe, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20537, https://doi.org/10.5194/egusphere-egu25-20537, 2025.

The impacts of extreme heat and other climate extremes have intensified with climate change, compounded by international pressures from geopolitical tensions that exacerbate socioeconomic inequalities and harm human wellbeing. This study examines factors affecting life expectancy in the United Kingdom, focusing on the relative influence of socioeconomic characteristics and climate change variables, such as heat and flood exposure. The primary research question explored whether wealth could offset the adverse effects of climate change on life expectancy. The analysis covered various age groups, from 0–9 years to 80–89 years, across UK local authority regions. For instance, among 40–49-year-olds, the life expectancy gap between low- and high-life expectancy regions in England was 2 years, 9 months, and 24 days (84.0 vs. 85.97 years). Socioeconomic factors and climate change indicators, including heatwave occurrence, accounted for 77% of this disparity, while extreme rainfall showed no significant effect. The findings highlight that climate change, particularly through the rising frequency of heatwaves, has significantly influenced life expectancy in certain UK regions. This highlights the critical need to address the interplay between climate risks and socioeconomic inequalities to safeguard public health and wellbeing.

How to cite: Brimicombe, C. and Otto, I.: Heat exposure can reduce life expectancy even across wealthy regions: a UK case study, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16500, https://doi.org/10.5194/egusphere-egu25-16500, 2025.

Heat stress events in China are becoming increasingly frequent and severe, exacerbated by the nation’s rapidly aging population. Elderly individuals, as a particularly vulnerable group, face heightened risks and have a reduced ability to withstand such hazards. However, research on the long-term dynamics of heat stress risks among the elderly remains limited. This study addresses this gap by employing the Intergovernmental Panel on Climate Change (IPCC) risk framework to evaluate the evolving heat health risks for the elderly in China since the start of the 21st century. By integrating satellite remote sensing, meteorological observations, and socio-ecological statistics, the study captures the dynamic interplay between hazards, vulnerabilities, and exposure. The findings reveal that the combination of rising heat hazard days and a worsening aging population has led to a steady increase in the elderly population exposed to heat stress, amplifying both vulnerability and exposure risks over time. Regional disparities in comprehensive risk are striking, driven by differing levels of aging and socio-economic development across China. The central region consistently exhibits the highest and fastest-growing comprehensive heat risk, while the northwest and northeast maintain the lowest risk levels. Conversely, socio-economically advanced provinces in the east, such as Shanghai and Beijing, show declining risk levels due to significant reductions in vulnerability facilitated by rapid social progress. This study provides a dynamic and regionally nuanced perspective on the intersection of aging and heat stress risks, offering critical insights to inform targeted policies and resource allocation. Its findings hold particular relevance for developing countries navigating the dual challenges of climate change and aging populations.

How to cite: Liu, C., Chen, S., Huang, J., Zhang, C., Lian, L., Jiang, Y., and Tu, X.: Dynamic assessment of heat stress risks among the aging population in China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4780, https://doi.org/10.5194/egusphere-egu25-4780, 2025.

In recent decades, ecosystems have faced extreme climatic events, such as high temperatures, which have significantly impacted human health, wildfires, and agricultural losses. These heat extremes are expected to continue increasing in frequency and intensity, necessitating a deeper understanding and close monitoring of these events.

The primary objective of this study is to quantify and compare the sectoral impacts of 1.5 °C and 2.0 °C global warming scenarios on human health, agriculture, and wildfire risks using high-resolution climate simulations. Health impacts were assessed using the Health Heat Index (HHI), while wildfire risk was analyzed using the Forest Fire Danger Index (FFDI), which evaluates the duration and frequency of fire seasons in terrestrial ecosystems. Agricultural impacts were quantified by estimating crop heat stress during thermal-sensitive periods, calculating anthesis heat stress (AHS), and normalizing production damage indices.

These analysis reveals a significant increase in areas exposed to critical levels of heat stress, affecting human health, ecosystems, and food security. Our results show a significant rise in risks measured by the HHI And the analysis of the FFDI reveals also an extension in the duration and frequency of fire-prone seasons. In agriculture, the assessment of heat stress during sensitive periods, particularly through the Anthesis Heat Stress Index (AHS), highlights worsening production losses.

These findings highlight the urgency of adopting ambitious mitigation strategies to minimize risks to vulnerable populations and preserve ecosystems and food security.

How to cite: Essoussi, S., El Morjani, Z. E. A., and Sadiq, A.: Assessing the Effects of Extreme Heat on Health, Agriculture, and Ecosystemsin Morocco under different levels of climate warming, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16229, https://doi.org/10.5194/egusphere-egu25-16229, 2025.

The extent to which changes in labour force outcomes can be attributed to historic climate change is currently unknown. Here, we combine robust estimates of the impact of climatic stressors on labour supply, labour productivity, and a combined metric of the two - effective labour, with novel historic climate forcing data to quantify the effect of historic climate change on labour. We do this at the global and regional level, taking explicit account of heterogeneity of working conditions. Glob- ally, effective labour in outdoor working conditions was 1.8 percentage points lower in 1901-2019 than it would have been without climate change. The attributable declines have increased over time, rising to 3.6 percentage points between 2001 and 2019. The highest declines have been in the relatively lower-income regions of Western Africa, South-Eastern Asia, and Middle Africa, where climate change has increased workforce inequalities. We also estimate the economic effects through impacts on GDP and find up to a 12% GDP loss for some regions. Our findings can help improve the design of better labour protections, improve worker health, enhance productivity and economic growth, and inform better climate adaptation and resilience.

How to cite: Dasgupta, S.: Attribution of historical changes in labour outcomes to climate change, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20600, https://doi.org/10.5194/egusphere-egu25-20600, 2025.

Extreme heat can substantially impact worker productivity, causing fatigue, loss of focus, and illness in the workplace. As extreme heat increases under climate change, substantial reductions in labour productivity are expected. According to some models, economic costs from decreased worker productivity will be larger than any other climate related impacts, and corporations are therefore interested in understanding their potential exposure and vulnerability to heat stress in the future. Workplace regulations (e.g. ISO) and epidemiological studies have previously been combined to develop continuous functions relating workplace heat stress to labour productivity. In this work, we utilise productivity loss functions with climate model projections for future extreme heat exposure to assess changes in labour productivity loss. We present a new modelling framework for providing labour productivity loss projections for several scenarios (SSPs), work intensities (low, moderate, and high), and regions, specifically designed for financial services. We include a model of air conditioning availability, with which the productivity loss estimates can be scaled according to the likely adoption and use of cooling systems in the workplace.  

How to cite: Starr, A., Woodhouse, S., Leach, N., Brennan, J., Reveley, G., Woodcock, C., Ramesh, K., Stables, J., Ramsamy, L., Sullivan, P., and Padilha, V. L.: Estimates of labour productivity loss from climate model projections of extreme heat: Implications for financial services  , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6084, https://doi.org/10.5194/egusphere-egu25-6084, 2025.