Heat Dome Effect

Syllabus: GS1/Physical Geography

Context

• The state of Assam has recently experienced unprecedented temperatures nearing 40°C in September, unusual for the region, which may be attributed to the Heat Dome Effect.

About Heat Dome Effect

• The heat dome effect is a type of high-pressure system (also known as anticyclone) that forms over a large area in the atmosphere, and causes extremely hot and dry weather conditions.
• The system traps hot air and prevents it from flowing to rise and cool.
• This air then becomes compressed and heats up, leading to a dome-shaped area of hot air that can persist for several days or even weeks.

• Due to climate change, heat domes have not only become more frequent but also a lot more intense.
  • The rising temperatures and changes in weather patterns are creating conditions that are assisting their formation.

Impact of Heat Domes

• Heat domes can cause dangerous heat waves causing the temperatures to shoot up. 
• They can also lead to drought conditions and wildfire as the hot and dry weather can quickly dry out vegetation and make it more susceptible to catching fire.
• It can also have severe impacts on human health, agriculture, and ecosystems.
• Heat domes can persist for several days to weeks, depending on atmospheric conditions. The longer they last, the more severe the impacts can become.

Heat Domes vs Heat Waves

• While many people use ‘heat domes’ and ‘heat waves’ interchangeably, heat domes are just one of the atmospheric conditions that can contribute to the formation of a heat wave.
• A heat wave is a prolonged period of excessively hot weather, often accompanied by high humidity. 
• Heat waves can occur for a variety of reasons, including the presence of a heat dome. 
• Heat waves can also occur without the presence of a heat dome, such as when warm, humid air masses from the tropics move to an area and stagnate for an extended period.

Source: IE