Canary Islands Face Saharan Dust and Extreme Heat

The Canary Islands are currently experiencing a significant atmospheric event as Saharan dust, known locally as 'calima,' arrives alongside an intense heatwave. The Spanish State Meteorological Agency (AEMET) has issued yellow warnings for all islands, indicating reduced visibility and potential health advisories.

Visibility is expected to drop to around 3,000 meters, with south-facing and coastal areas anticipated to be the most affected. Dust particle concentrations may exceed 200 micrograms per cubic meter in some locations, raising concerns for respiratory health. This phenomenon, originating from the Sahara Desert and carried by southerly to southeasterly winds, is a recurring event, particularly common in winter but occurring year-round. Since 1980, the islands have recorded an average of approximately 24 calima days per year, with each event lasting an average of 1.8 days.

Temperatures are also soaring, with Gran Canaria expecting highs of 36°C, possibly reaching 37°C. Other islands could see temperatures up to 34°C, especially in their southern and southwestern regions. This heat surge is attributed to a Saharan air mass moving into the archipelago.

The Canary Islands government has issued a pre-alert due to the calima, advising residents and visitors to limit outdoor activities and keep windows closed to minimize exposure to dust and heat. The health implications of calima are significant, particularly for individuals with pre-existing respiratory or cardiovascular conditions, as fine dust particles can worsen symptoms like coughing, nasal congestion, and eye irritation. Health authorities recommend that vulnerable populations remain indoors, stay hydrated, and keep necessary medications accessible.

Historically, intense calima events have impacted the islands, including a notable instance in January 2022 that reduced visibility to as low as 1,000 meters in some areas, affecting airport operations. A severe calima in February 2020 was also described as historic, with sand concentrations reaching over 3500 μg/m^3. Authorities are also emphasizing fire prevention measures in forested areas due to the increased risk of wildfires during these hot and dry conditions. Drivers are advised to reduce speed due to potential visibility issues on roads.

The phenomenon is expected to primarily affect Gran Canaria, Lanzarote, and Fuerteventura, with dust clouds potentially descending to midland and coastal areas. While generally more prevalent in the eastern islands due to proximity, the calima can extend to the entire archipelago due to trade winds. Calima episodes typically last between three to five days.