All you have to do is Google the phrase “extreme heat warning – today,” and pages of warnings are revealed, from New Jersey, Maryland, and Rochester, New York to Arizona, San Diego, California, and even Washington, D.C.
And as the heat builds, by Friday, it will be brutal. “Friday will be suffocating across much of the eastern U.S., with the heat index 100 degrees to 110 degrees from the Plains to the Great Lakes and the Middle-Atlantic to NYC,” tweeted BAM Weather meteorologist Ryan Maue.
Friday will be suffocating across much of the Eastern U.S. with heat index 100°-110°F ️from the Plains to Great Lakes and Middle-Atlantic to NYC.
108° Washington D.C.
109° Chicago
109° Detroit fe5DOLGNhL— Ryan (@RyanMaue) July 16, 2019
Our future under extreme heat
Extreme heat is among the deadliest weather hazards society faces. During extremely hot days, heat-related deaths spike and hospital admissions for heat-related illnesses rise, especially among people experiencing poverty, elderly adults, and other vulnerable groups.
In a study published in the peer-reviewed journal IOP Science on Tuesday, July 16, 2019, scientists used 18 climate models to predict changes in the heat index—the mix of heat and humidity that reflects how hot it feels—across the contiguous U.S. as global temperatures rise over the coming decades.
What the study found is actually not surprising to most folks – Especially seeing that a good part of the country is experiencing an extended period of extreme heat this week into the weekend.
The heat will be on from the Plains to the East Coast with the daytime heat index well into the 100’s starting mid-week.”
The number of days when the average temperature will feel like 100 degrees in the Lower 48 states will double, from about two weeks at the end of the last century to 30 days by mid-century, even if we succeed in reducing greenhouse gas emissions a little bit.
In a much longer report by the Union of Concerned Scientists, they point out: “If we wish to spare people in the United States and around the world the mortal dangers of extreme and relentless heat, there is little time to do so and little room for half measures.”
The Heat Index – Why it is important
Heat is more harmful to human health when humidity is high because humid air hinders the evaporation of sweat, and thus reduces the body’s ability to cool itself. The Heat Index is calculated using instantaneous or hourly temperature (T) and relative humidity (RH) data.
To determine the effect of both heat and humidity, the National Weather Service formulated the heat index based on the range of warm-season conditions we typically see on Earth. As the climate warms, we will increasingly find ourselves with heat index values that are off the charts.
The number of heat-related injuries and illnesses, including deaths, will increase along with the rising temperatures if we continue on with a “business as usual” attitude. The problem then becomes one with socio-economic issues as well as health issues.
Heat extremes also affect the economy of rural areas, as both crop and livestock production decline with extreme temperatures. Dairy livestock are particularly sensitive to heat stress. As a result, heat stress currently costs the average US dairy an estimated $39,000 annually—a cost that is projected to increase with future warming.
The Union of Concerned Scientists leaves us with a warning: “We now face a choice: to protect what we can of the future for today’s children and youth, or to let them face the gravest consequences of the course we have set.”
