Humid Heat Waves
Recent studies highlight the increasing threat of humid heat waves, particularly in tropical and subtropical areas like India. A new research revealed the relationship between rainfall, soil moisture, and the onset of these extreme weather events.
About Humid Heat Waves
- Humid heat waves occur when high humidity levels prevent effective cooling of the human body.
- They are characterised by high temperatures combined with elevated humidity, which severely impair the body’s ability to regulate temperature through sweating. This phenomenon poses health risks, especially in densely populated regions already experiencing high temperatures.
- The study indicates that these events have intensified since 1979, with climate change exacerbating their frequency and severity. The lowest temperature at which air can be cooled by evaporation is known as the wet-bulb temperature (Twb).
- When the Twb reaches around 35°C, humans struggle to cool down. Vulnerable populations, such as the elderly and very young, face even greater risks.
Climate Change and Humid Heat
Climate change is driving more extreme humid heat events. For instance, April 2023 saw severe humid heat waves in South and Southeast Asia. As global temperatures rise, the frequency of such events is expected to increase, particularly in regions already prone to high humidity and heat.
Role of Rainfall and Soil Moisture
The research identifies important link between recent rainfall patterns and the occurrence of humid heat waves. In arid regions, such as northwestern India, humid heat waves often follow rainfall. The moisture from rainfall evaporates, increasing humidity levels. Conversely, in humid regions, high soil moisture usually exists, but reduced sunlight due to cloud cover limits evaporation. After rainfall subsides, clearer skies lead to increased surface warming, contributing to humid heat conditions.
Implications for Early Warning Systems
The findings suggest a potential for developing early warning systems for humid heat waves. The strong correlation between soil moisture, precipitation, and humid heat means that satellite technology could provide real-time observations. By integrating these observations with climate models, forecasts can be improved, enhancing preparedness for heat waves.
Future Research Directions
Despite the insights gained, the meteorological processes driving humid heat waves remain poorly understood. Further research is necessary to elucidate these processes and improve predictive capabilities. Understanding the dynamics of humid heat waves will be crucial for mitigating their health impacts as climate change progresses.
| Related | |
|---|---|
