This weekend, nearly 200 million Americans will be exposed to temperatures of 32 ° C and higher. As humidity increases, many cities on the East Coast and Midwest will feel more like 43 ° C.
According to the Centers for Disease Control (CDC), heat waves have killed on average more people than any other extreme weather event in the US.
Extreme heat refers to a period of two to three days of high heat and humidity at temperatures above 90F (32C).
After the hottest June on earth ever, the US Weather Service (NWS) estimates that more than 1
What can this kind of heat do? do.
. 1 Air conditioners make cities warmer
According to a US Energy Information Administration (EIA) report from 2018, 87% of US households use air conditioning. Air conditioning systems use power grids during heat waves and can lead to city-wide failures.
In cities, this means that millions of devices – even in cars, buses and trains – constantly emit heat to the atmosphere. Studies have shown that the additional heat of the air conditioner can increase temperatures by up to 2 ° C. And when it gets warmer, our thermostats will turn down and the cycle will continue.
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But things go further than just an increasingly hot summer season – emissions from air conditioning systems and their refrigerants contribute to climate change. Man-made greenhouse gases used in air conditioning systems, referred to as fluorocarbons (HFCs), are a thousand times stronger than carbon dioxide in the atmosphere.
In cities, the circulation is reinforced by concrete, asphalt, steel and glass, creating an urban heat island.
. 2 Aircraft can not take off
When the temperatures get too high, the planes are grounded.
Extreme heat reduces the air density and the amount of lift that an airplane can take off. At temperatures of 49 ° C (120 ° F), dozens of Phoenix flights were canceled during a 2017 heatwave.
Smaller aircraft are affected first, but larger Boeing or Airbus jets have maximum operating temperatures of 52 ° C (126 ° F), AZ Central reported.
. 3 Roads can melt – or explode
In heat waves, concrete and asphalt are not performing well.
Asphalt warps and melts. When it comes to water, concrete can sometimes explode or break up.
This week, local media in Kansas have reported several cases of cracked and twisted roads as temperatures rise.
In Iowa, a city mayor said, old concrete roads With high water from this source soaked pipes explode and damage the sewers.
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4. Baking Cookies in the Car
The NWS outpost in Omaha, Nebraska, demonstrated how hot vehicles can get into heat waves when cooking American biscuits on their arms.
Temperatures peaked at 85 ° C – not enough for a proper casserole, but certainly too hot for humans or animals to survive.
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According to the National Meteorological Service, 21 small children have died in hot cars this year.
. 5 Metal gets hotter
Not surprisingly, everything that heats up in a heatwave gets even hotter.
When it comes to power lines, it can cause dangerously low deflections. If the lines hang so low that they touch the ground or the trees, they may have a short circuit.
As the metal expands, kinks may form on the rails of the train. In 2012, a "heat break" caused a 32-car freight train to derail and fly off an overpass. A similar derailment occurred in 2017. Experts said Fox 26 News has derailed more than 2,100 trains over the last 40 years due to these thermal deformations.
Metal components in drawbridges can expand and become inoperative – in the past year in Chicago f irefighters had to haul down a drawbridge in the inner city so they could be used.
. 6 Agriculture suffers a blow
The crops also feel the heat.
Midwestern farmers warn that vegetables wither in the heat and farm productivity falls. This worsens the situation after a historic flood season this spring. Soybean farmers also say that the dry conditions could cause an increase in spider mites and other plant diseases.
. 7 Smog worsens
Extreme heat exacerbates air pollution, which can be dangerous to the very young, the elderly, and anyone with respiratory problems.
In the capital of the country, where the mayor has imposed heat protection, officials warned that air quality would reach unhealthy levels for these sensitive groups over the weekend.