Historic heat wave in Canada caused due to Heat Dome
Part of: GS Prelims and GS I – Geography
In news
Recently, the Pacific Northwest and some parts of Canada recorded temperatures around 47 degrees, causing a “historic” heat wave.
This is a result of a phenomenon referred to as a “heat dome”.
The western Pacific ocean’s temperatures have increased in the past few decades and are relatively more than the temperature in the eastern Pacific.
Phenomenon of heat dome
A heat dome is an area of high pressure that parks over a region like a lid on a pot, trapping heat.
The phenomenon begins when there is a strong change in ocean temperatures.
The gradient causes more warm air, heated by the ocean surface, to rise over the ocean surface (Convection).
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.
This strong change in ocean temperature from the west to the east causes heat dome (HD).
HD also prevents clouds from forming, causing more Sun’s radiation to reach the Earth’s surface.
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.
Effects of Heat Dome
The temperatures of homes rise unbearably high, leading to sudden fatalities, if such homes do not have AC.
Damage crops, dry out vegetation and droughts.
Rise in energy demand, especially electricity, leading to pushing up rates.
Fuel to wildfires, which destroys a lot of land area in the US every year.
What are Jet streams?
Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere.
The winds blow from west to east in jet streams but the flow often shifts to the north and south.
