High temperatures in February 2024 Morocco heatwave mostly strengthened by human-driven climate change

Contact Authors

• Tommaso Alberti,INGV, Italy 📨tommaso.alberti@ingv.it 🗣️Italian, English

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

Citation

• Alberti, T., & Faranda, D. (2024). High temperatures in February 2024 Morocco heatwave mostly strengthened by human-driven climate change. ClimaMeter, Institut Pierre Simon Laplace, CNRS. https://doi.org/10.5281/zenodo.14163690

Press Summary (First published 2024/02/22)

• Heatwaves similar to the February 2024 Morocco heatwave are between 1 ºC and 2 ºC hotter in the present than they would have been in the past.

• This was a somewhat uncommon event.

• We ascribe the high temperatures of the February 2024 Morocco heatwave to human driven climate change and natural climate variability likely played a minor role.

Event Description

On Wednesday, February 14th, 2024, a record-breaking heatwave affected Morocco, producing summer-like conditions with temperatures soaring above 36 °C, setting a new record for the month. Such extreme temperatures in Morocco at this time of year are highly unusual, typically reserved for the hottest days of spring and summer. Normally, mid-February sees temperatures around 20 °C, marking a significant departure from the norm by 15 °C. Record-breaking heat was reported across the whole country, with Agadir reaching 36 °C, Essaouira hitting a maximum of 36.4 °C, and Tan-Tan recording the highest temperature at 36.6 °C. This surpasses the previous monthly record set in 1960, when Nouasseur registered 36.0 °C in February.

The unprecedented warmth can be attributed to several factors. Morocco often experiences hot weather due to the influx of dry air from the desert. Additionally, the foehn effect, amplified by the proximity of the Atlas Mountains, contributed to the heat. As south-easterly winds descended rapidly on the northwest side of the mountains, they lost moisture and rapidly warmed, intensifying the heatwave. It persisted across southern and central Morocco, with orange and yellow heatwave warnings issued by the Moroccan Directorate General of Meteorology. The prolonged period of high temperatures and dry conditions raises concerns about wildfires and droughts, prompting authorities to also implement water rationing measures and advise caution, especially for vulnerable groups such as the elderly and those with respiratory illnesses. The heatwave also poses challenges for transportation, with potential disruptions in urban areas due to overheated vehicles and increased demand for electricity leading to localized power outages. Additionally, high temperatures may impact outdoor activities, necessitating precautions to prevent heat-related illnesses and ensure public safety.

The Surface Pressure Anomalies reveal negative anomalies on the Atlantic Ocean and positive anomalies over continental Africa. This causes advection of warm air from southern latitudes into Northern Africa. Consequently, positive Temperature Anomalies reaching up to 7 °C are observed in a large portion of Northern Africa. Based on Precipitation Data this event was characterized by dry conditions in most regions, while Windspeed Data reveals the presence of moderate winds over ocean areas mainly.

Climate and Data Background for the Analysis

Climate change is exacerbating heatwaves in Western Africa, leading to increased mortality, impacts on agriculture, human health, and infrastructure. More in detail, observed climate change has intensified hot extremes, including heatwaves, in urban settings, aggravating air pollution events and compromising key infrastructure 2. Heat extremes, such as hot days and hot nights, have increased in frequency since 1980 in Africa, particularly in North, West, and Central Africa (IPCC AR6 WGII SPM - p11) . Future climate change projections indicate that increasing temperatures will cause tens of thousands of additional deaths under moderate and high global warming scenarios in North, West, and Central Africa (IPCC AR6 WGII FR - Page 257). Furthermore, the number of days with maximum temperatures exceeding 35 °C is projected to increase in Western Africa, potentially reaching 50-100 days by 2050 under certain scenarios (IPCC AR6 WGI FR - Page 1808). Increases in the number of hot days and nights, as well as heatwave intensity and duration, have had negative impacts on agriculture, human health, water availability, energy demand, and livelihoods in Africa (IPCC AR6 WGII FR - Page 1411). Regarding the impacts, climate change has already reduced food security in Africa through losses in crop yields, livestock, and fisheries, with risks to crop yields projected to increase further. Finally, resilient infrastructure and technologies are required to cope with increasing climate variability and change in Africa, including improving housing to limit heat exposure and enhancing water and sanitation infrastructure.

ClimaMeter Analysis

We analyze here (see Methodology for more details) how events similar to the pressure system leading to February 2024 Morocco heatwave have 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 [20°W 10°E 25°N 40°N]. The Surface Pressure Changes show that pressure over southern Portugal and Spain has decreased in more recent events, with an increase observed over Atlantic. The Temperature Changes show that similar events produce temperatures in the present climate that are between 1 ºC and 2 ºC hotter than what they would have been in the past, over a large area roughly corresponding to Morocco. The Precipitation Changes and Windspeed Changes show no significant changes. We also note that Similar Past Events are shifting from February to March.  The Changes in Urban Areas show that Agadir, Casablanca and Rabat are about 1.5 °C warmer in the present than in the past. They also experience windier and drier conditions in the present than in the past.

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 February 2024 Morocco heatwave are between 1 ºC and 2 ºC hotter in the present than they would have been in the past. We interpret the February 2024 Morocco heatwave as an uncommon event whose characteristics can be ascribed to human driven climate change.