Heated dome brings record high temperatures to the West, exacerbating drought and wildfires
Much of the western United States is going through a punishing and ruthless summer of heat, drought and wildfires. Hundreds of heat records have been broken and drought is affecting 94% of the West. The wildfires burned nearly 4,000 square miles, an area larger than the states of Delaware and Rhode Island combined.
This cauldron of misery has been exacerbated by a sprawling heat dome that has roamed the West this summer, causing temperatures to soar. A thermal dome occurs when the atmosphere traps hot air like a cover or hood.
What is a heated dome?
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A thermal dome is the result of a sharp change in ocean temperature from west to east in the tropical Pacific Ocean during the previous winter, according to the National Ocean Service. Warm air from the western part of the Pacific Ocean is trapped in the jet stream as it approaches land.
When this hot air arrives above the earth, the atmosphere traps it. Winds can move the thermal dome; hence, it is also called heat wave.
Drought-stricken Western states
Nearly 60 million people in the West experience drought, from Washington to New Mexico. Nearly 95% of the region is in a drought, the highest percentage in at least 20 years, according to the US Drought Monitor.
“The extreme and record-breaking heat leading up to this week resulted in rapidly deteriorating drought conditions in the Pacific Northwest, northern Great Basin and the northern Rockies,” the Drought Monitor said.
In Oregon, where the drought has intensified from severe to exceptional, soil moisture, stream flow, and the standard evapotranspiration index of precipitation (a monitoring indicator of drought which includes the effects of precipitation and temperature) shows conditions to be among the driest since 1895, the Drought Monitor said this month.
Video: How a heated dome is causing record temperatures in Western Canada (Global News)
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Montana recorded less than 25% of its normal precipitation in June, which is historically its highest precipitation month. The impacts there included grasshopper infestations.
Excessive heat contributes to forest fires
The hot, dry air under the heated dome created powder keg conditions conducive to the spread of wildfires, the Capital Weather Gang said.
“A large high pressure dome will continue to bring extreme heat to the northern Rockies and northern plains through the middle of this week,” AccuWeather meteorologist Robert Richards said Monday.
In addition to above-average temperatures, the combination of extreme drought, gusty winds and thunderstorm lightning could make conditions across the West conducive to the uncontrollable formation and spread of wildfires this year. week, the National Weather Service said.
The heated dome can push temperatures 10 to 20 degrees above average. Some places in Montana, Idaho and North Dakota could hit triple digits this week, AccuWeather predicted.
Role of climate change in extreme heat
Extreme conditions like the one the West is experiencing this summer are often due to a combination of unusual, random, short-term and natural weather conditions, accentuated by long-term human-caused climate change.
Scientists have long warned that the weather will get wilder as the world warms. Climate change has made the West much hotter and drier over the past 30 years. Special calculations will be needed to determine how much global warming is to blame, if any, for a single extreme weather event such as this summer’s extreme heat.
“With regard to climate change, the jet stream is expected to become more rippled in the future as average temperatures continue to rise, making these deviations large, and subsequently heat events. extreme, more frequent, ”said Randy Adkins, AccuWeather senior meteorologist.
Smoke from wildfires reaches most of the United States
SOURCE NOAA; PHOTO image above: GoogleEarth; Contributing John Bacon, USA TODAY; The Associated Press
This article originally appeared on USA TODAY: Heat Dome Brings Record High Temperatures to the West, Exacerbating Drought and Wildfires