Event Description

From June 16th to June 18th, during the Hajj pilgrimage, Saudi Arabia saw temperatures reach 47°C on Sunday with temperatures at least 1.5 to 2°C higher in Mecca and Medina, the two cities at the heart of Hajj pilgrimage. This year, more than 1.8 million Muslim pilgrims were expected to arrive, according to the Saudi General Authority for Statistics.  Extreme heat claimed the lives of at least 550 pilgrims, with temperatures at Mecca's Grand Mosque reaching a scorching 51.8 degrees Celsius. The majority of the deceased were Egyptian, accounting for 323 deaths, with additional fatalities including 60 Jordanians and 5 Iranians. Despite these reports, Saudi Arabia's health ministry attributed the fatalities to pre-existing conditions and the vulnerable health of the pilgrims. 

The Surface Pressure Anomalies reveal a negative anomaly over Egypt and a high pressure anomaly over Saudi Arabia. These conditions favor warm winds from the Red Gulf which results in up to +7°C Temperature anomalies. Precipitation data show absence of precipitation in a large part of the region analyzed. Windspeed data show low to moderate winds.

Climate and Data Background for the Analysis

The extreme heat in the Middle East is a clear manifestation of the impacts of climate change, with rising temperatures, heatwaves, and droughts posing significant challenges to the region's societies, economies, and ecosystems, as detailed in the IPCC AR6 report.  Warming has led to increased frequency, intensity, and duration of heat-related events, including heatwaves, in most land regions, particularly in the Middle East and North Africa ( IPCC AR6 WGI FR - Page 1625).  Climate change is contributing to humanitarian crises in the region, with extreme heat driving displacement and exacerbating food insecurity and malnutrition. Changes in land conditions, such as decreased snow cover and increased evapotranspiration, can enhance winter warming and reduce growing season warming in boreal regions, impacting heat extremes. The Middle East is projected to experience strongly increasing heat extremes in the 21st century, with implications for summer dryness and heat wave amplitude (IPCC SR CCL SPM). The region is among those with the strongest projected increase in hot extremes, leading to severe droughts and other climate-related impacts. Rising temperatures trigger extensive evaporation, leading to shrinking water resources, drier soils, reduced river flow, and longer and more intense drought spells in the already dry and warm Mediterranean climate.

Our analysis approach rests on looking for weather situations similar to those of the event of interest having been observed in the past. For this event we have medium-low confidence in the robustness of our approach given the available climate data, as the event is unusual in the data record

ClimaMeter Analysis

We analyze here (see Methodology for more details) how events similar to the high temperature in the Saudi Arabia heatwave changed in the present (2001–2023) compared to what they would have looked like if they had occurred in the past (1979–2001) in the region [25°W 50°W 15°N 35°N]. The Surface Pressure Changes show that similar events  do not display significant changes in the present climate than what they would have been in the past over the region of interest. The Temperature Changes show that similar events produce temperatures in the present climate up to 2.5 °C warmer than what they would have been in the past, over a large area of the region analyzed. The Precipitation Changes do not show any significant variations. Windspeed Changes indicate up to 7 km/h windier conditions over Northwest and South Arabia. We also note that Similar Past Events previously mainly occurred in May and July, while in the present climate they are mostly occurring in June. Changes in Urban Areas reveal that Riyadh and La Mecca are at least 1.5 °C warmer in the present compared to the past. These cities also experience windier (up to 1.5 km/h) conditions.

Finally, we find that sources of natural climate variability did not influence the event. This means that the changes we see in the event compared to the past may be primarily due to human driven climate change.

Conclusion

Based on the above, we conclude that heatwaves similar to the Saudi Arabia heatwave are up to 2.5 °C warmer than the warmest heatwaves previously observed in the country. We interpret the Saudi Arabia heatwave as a very uncommon event whose characteristics can mostly be ascribed to human driven climate change.

Contact Authors

-Davide Faranda, IPSL-CNRS, France +33681038467 📨davide.faranda@lsce.ipsl.fr 🗣️French, Italian, English

-Tommaso Alberti, INGV, Italy +393461692775 📨tommaso.alberti@ingv.it 🗣️ Italian, English