Portland city in Oregon, US, temperatures as high as 46 degree Celsius

Portland city in Oregon, US, temperatures as high as 46 degree Celsius

Subject : Environment

Context : The temperatures being reported from the Pacific Northwest and some parts of Canada are part of a “historic” heat wave as a result of a phenomenon referred to as a “heat dome”.

Concept :

Heat Dome

• It is essentially a mountain of warm air built into a very wavy jet stream, with extreme undulations.
• It develops when there is a large poleward shift in the jet stream, which becomes wavy and elongated.
• The National Oceanic and Atmospheric Administration (NOAA) says that to understand what causes a heat dome, one should liken the Pacific ocean to a large swimming pool in which the heater is turned on.
• The portions of the pool close to the heating jets will warm up faster once the heater is on and therefore, the temperature in that area will be higher.
• In the same way, the western Pacific Ocean’s temperatures have increased in the past few decades and are relatively more than the temperature in the eastern Pacific.
• The strong change in ocean temperature from the west to the east is what a team of scientists believe is the reason for the heat dome.
• The reason that the planet Venus is the hottest in the Solar System is because its thick, dense cloud cover traps the heat at the surface, leading to temperatures as high as 471 degree Celsius.