the most high heat wave Records in the Pacific Northwest continued to break records for another day. Millions of people are now under warning of excessive heat. Many are sweltering with triple-digit temperatures without air conditioning in a region that often has mild summers.
Behind the adversity is a weather phenomenon known as a. thermal dome.
What is a thermal dome?
The thermal dome is a warm mountain, essentially built in undulating currents. with a very big wave When jet streams, which are strong winds in the upper atmosphere, become undulating and long. The pressure system may clamp and freeze or get stuck where it would normally not be.
In this case, the high pressure line, a thermal dome, was embedded in the Pacific Northwest. Acts as a barrier in the atmosphere to prevent air movement. One type of block is called Omega block because it looks like the Greek letter Omega. and hot air will gather inside
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Why are these temperatures so high?
In high-pressure areas, such as thermal domes, air sinks. This compresses the air on the ground and through compression heats the column. Wind is also moving down the mountains into cities such as Seattle. Myle and Portland The downward movement also generates heat.
These local impacts are compounded by the warming background of climate change. That has warmed the Pacific Northwest by 3 to 4 degrees Fahrenheit since pre-industrial times. intensify the already strong heat wave
What areas are currently affected?
The extreme heat extends from British Columbia in southern Canada into Washington, Oregon, Idaho, Montana and California. The city of Lytton in British Columbia recorded 116 degrees on Sunday. Breaks Canada’s all-time record of 3 degrees.
Portland broke an all-time high on Saturday, hitting 108 degrees, then passed again Sunday with a reading of 112 degrees Monday afternoon. The city surprisingly reached 115 degrees.
Seattle also set a new all-time record of 104 on Sunday and are expected to easily beat the top forecast of 111 on Monday. That would beat the old daily record by 21 degrees.
How long will it last?
The heat will weaken near the coast and in Seattle and Portland on Tuesday as temperatures drop into the 90s, but record-breaking heat will last through the week in the interior of the Pacific Northwest.
How unusual is this heat wave?
“Unprecedented” doesn’t do justice, statistically, this would be. Happens once in 1,000 years in normal weather But our climate is no longer normal: The air is heating up from human-caused climate change. So these once almost impossible heatwaves are not only possible. But there are still more possibilities in the coming years and decades to come.
Is this related to climate change?
There are two weather connections. The first is clear: the atmosphere is warmer than it was 100 years ago, and the heat wave is warmer than ever. But when you increase the average temperature by a few degrees Your extremes, such as a heat wave, will become extreme with more speed
The second is related to strong currents. There is a lot of controversy in climate science circles about this. Some scientists have found a link between warming climates and more undulating currents. which can cause more intense heat waves intensified storm and more severe floods This is because wavy winds force warmer north and cooler south. It also slows down the progression of the system. This increases atmospheric instability and the effects are more severe. Although the science of tidal currents makes sense, But it is still intensively studied to verify its validity.
