Breakdown: Why extreme heat is so deadly

MEMPHIS, Tenn. (WMC) - Heat waves kill more people than any other type of severe weather in the U.S. And climate change is making them more frequent and unpredictable.

In June a massive “heat dome” smothered the famously temperate Pacific Northwest, subjecting parts of Washington State, Oregon and western Canada to blistering and unprecedented temperatures.

Lytton, British Columbia, set an all-time Canadian record with a searing 121.3 degrees Fahrenheit. A day later, most of that village was destroyed by a huge wildfire. About 90% of Lytton is burned, according to Brad Vis, a member of Parliament representing the area. In response to Lytton’s devastation, Prime Minister Justin Trudeau announced federal aid would be sent to help the village rebuild.

During another western heat wave in early July, California’s Death Valley reached a scorching 130 degrees F—just shy of its record of 134 degrees F, which was reported in 1913.

A thread from NWS Las Vegas on the preliminary high temperature of 130°F recorded yesterday in Death Valley.

If verified, it would tie for the 3rd most reliably measured, all-time global high temperature and will be the hottest temperature officially verified since July of 1913. https://t.co/FfHMP58xyB
— NWS Columbia (@NWSColumbia) August 17, 2020

According to the Centers for Disease Control and Prevention, extreme heat is defined as summertime temperatures that are much hotter and/or humid than average. Because some places are hotter than others, this depends on what’s considered average for a particular location at that time of year. Humid and muggy conditions can make it seem hotter than it really is.

These heat waves pose a major risk to public health. In an average year in the U.S., heat kills more people than any other type of extreme weather.

The U.S. Natural Hazard Statistics provide statistical information on fatalities, injuries and... — The U.S. Natural Hazard Statistics provide statistical information on fatalities, injuries and damages caused by weather related hazards. These statistics are compiled by the Office of Services and the National Climatic Data Center from information contained in Storm Data, a report comprising data from NWS forecast offices in the 50 states, Puerto Rico, Guam and the Virgin Islands.(NWS)

A recent U.S. Centers for Disease Control and Prevention report found there were more than 3,500 emergency department visits for heat-related illness this past May and June in a region that includes Alaska, Idaho, Oregon and Washington State. Nearly 80 percent of these visits occurred between June 25 and 30, when Oregon and Washington were experiencing the worst of the wave.

The human body functions best at 98.6 degrees F. When it overheats and becomes dehydrated, the blood thickens. The heart has to pump harder, and it and other organs can be seriously damaged. The body has mechanisms to rid itself of excess heat—most notably sweating. But at a certain point, that fails to work, especially if humidity is high and perspiration cannot evaporate. This can result in heat related illnesses.

Heat-related illnesses, like heat exhaustion or heat stroke, happen when the body is not able to properly cool itself. While the body normally cools itself by sweating, during extreme heat, this might not be enough. In these cases, a person’s body temperature rises faster than it can cool itself down. This can cause damage to the brain and other vital organs.

During extremely hot and humid weather, your body's ability to cool itself is challenged. When... — During extremely hot and humid weather, your body's ability to cool itself is challenged. When the body heats too rapidly to cool itself properly, or when too much fluid or salt is lost through dehydration or sweating, body temperature rises and you or someone you care about may experience a heat-related illness. It is important to know the symptoms of excessive heat exposure and the appropriate responses. The Centers for Disease Control and Prevention provides a list of warning signs and symptoms of heat illness, and recommended first aid steps.(NOAA National Weather Service)

Some factors that might increase your risk of developing a heat-related illness include:

High levels of humidity
Obesity
Fever
Dehydration
Prescription drug use
Heart disease
Mental illness
Poor circulation
Sunburn
Alcohol use

Older adults, the very young, and people with mental illness and chronic diseases are at highest risk. However, even young and healthy people can be affected if they participate in strenuous physical activities during hot weather.

Summertime activity, whether on the playing field or the construction site, must be balanced with actions that help the body cool itself to prevent heat-related illness.

Copyright 2021 WMC. All rights reserved.