Heatwaves in Italy disrupt sleep and physiological cooling

Italy is experiencing intense heat conditions characterized by high daytime temperatures and 'tropical nights' where minimum temperatures remain above 25°C. This heat is driven by an anticyclonic structure causing subsidence, where descending air compresses and warms, alongside Saharan air masses moving across the Mediterranean.

These elevated nighttime temperatures significantly impact human physiology. To facilitate sleep, the body's core temperature must typically drop by approximately 1°C. However, when ambient temperatures remain near 30°C, the hypothalamus struggles to trigger distal vasodilation and efficient heat dissipation. This leads to increased sweating and a fragmented, less restorative sleep cycle. Studies indicate that nights exceeding 25-30°C can reduce sleep duration by 10-15 minutes, posing long-term risks to cardiovascular health, the immune system, and cognitive functions.