HEAT DOME

TAG: GS:1- GEOGRAPHY

CONTEXT: Recently, Assam witnessed temperatures around 40 degrees Celsius in the last week of September 2024 due to the ‘heat dome effect’ that people in the northeastern state have been experiencing for the previous few days.

EXPLANATION:

About the Heat Dome:

• A heat dome occurs when the atmosphere traps hot ocean air like a lid or cap.
• As per National Oceanic and Atmospheric Administration (NOAA), USA, a heat dome is created when strong high-pressure atmospheric conditions combine with weather patterns like La Niña.
  • They are more likely to form during La Niña years like 2021, when waters are cool in the eastern Pacific and warm in the western Pacific. creating vast areas of sweltering.

Causes of Formation of Heat Dome:

• Change in Ocean Temperature: The phenomenon begins when there is a strong change (or gradient) in ocean temperatures.
• In the process known as convection, the gradient causes more warm air, heated by the ocean surface, to rise over the ocean surface. As prevailing winds move the hot air east, the northern shifts of the jet stream trap the air and move it toward land, where it sinks, resulting in heat waves.

Impact of the Heat Domes:

• Risk of Wildfires: The heat domes act as fuel to wildfires, which destroys a lot of land area every year in countries like the US.
• Prevents Cloud Formation: The condition also prevents clouds from forming, allowing for more radiation from the sun to hit the ground.
• Heat Strokes and Sudden Fatalities: The very high temperatures or humid conditions pose an elevated risk of heatstroke or heat exhaustion.

• Older people and people with chronic illnesssuch as heart disease, respiratory disease, and diabetes are more susceptible to heatstroke, as the body’s ability to regulate heat deteriorates with age.

• • • Houses without air conditioners experience an unbearable rise in temperature of their home which can lead to sudden deaths.
  • Effect on Vegetation: The trapping of heat can also damage crops, dry out vegetation and result in droughts.
  • Increased Energy Demands: The sweltering heat wave also leads to rise in energy demand, especially electricity, leading to pushing up rates.
  • Power Related Issues: Heat waves are often high mortality disasters.
    • Avoiding heat-related disasters depends on the resilience of the electrical grid, which can fail if electricity demand due to air conditioning use exceeds supply.
    • As a result, there is the double risk of infrastructure failure and health impacts.

Source:

https://www.downtoearth.org.in/climate-change/why-is-assam-boiling-hot-heat-dome-effect-say-experts