For the second day in a row, the Pacific Northwest’s most intense heat wave has broken records.
(Pacific Northwest – The states of Washington and Oregon are commonly included in this region of the northwest United States. The word is also used to refer to British Columbia’s southwest region.)
Millions of people are under excessive heat warnings right now, with many of them sweating in triple-digit temperatures without air conditioning in an area where summers are generally pleasant.
A weather phenomenon known as a “Heat dome” is to blame for the agony.
A heat dome is a mountain of warm air constructed into an extremely wavy jet stream with extreme undulations. Pressure systems can pinch off and become stranded or trapped in places they shouldn’t be when the jet stream — a belt of strong wind in the high sky — becomes very wavy and extended.
The heat dome, which is a ridge of high pressure, has become trapped in the Pacific Northwest in this example. It acts as a stumbling block in the atmosphere, preventing the weather from moving. The block is known as an Omega block because it resembles the Greek letter Omega and the heated air is trapped inside.
What causes these severe temperatures?
High-pressure areas, such as heat domes, have sinking air. This compresses the air on the ground and heats the air column as a result. Furthermore, winds are blowing downslope from the mountains into places like Seattle and Portland, causing heating.
These local impacts, when paired with climate change’s background warming, which has warmed the Pacific Northwest by around 3 to 4 degrees Fahrenheit since pre-industrial times, intensifies an already intense heat wave.