Air temperatures during record-setting heat wave in the Pacific Northwest were bad enough. But the ground was on a whole other level.
Stunning new satellite imagery from the European Space Agency’s Sentinel-3 satellite shows ground temperatures reached as high as 63 degrees Celsius in Wenatchee, Washington. Apparently even the Earth we stand on isn’t safe from the climate crisis.
The Pacific Northwest has been roasting under a record heat dome for days on end. That’s resulted in consecutive days of temperature records falling, including some that have stood for decades. Those temperatures are based on air readings. Most weather stations in the U.S. National Weather Service’s monitoring network sit anywhere from 1.3 to 1.8 metres off the ground to capture accurate readings. They’re also situated on level ground as far from concrete as possible. That’s certainly helpful for long-term records at specific places, and the data from those stations offer conclusive proof of how much the world has warmed.
But satellites can provide a different flavour for understanding heat. The Sentinel-3 satellite has a sensor dubbed the Sea and Land Surface Temperature Radiometer that allows it to capture various views of, you guessed it, the surface temperature of the Earth — how hot the literal ground beneath your feet is. The same sensor revealed shocking heat in Siberia earlier this month, and it gives a whole new perspective to the Pacific Northwest heat wave. Heat in the air can dissipate, but the ground can hold and build heat over longer periods once air temperatures crank up. That’s particularly true in places with lots of concrete, which is why you can fry an egg on the footpath on hot days, but trying to sous vide it using air temperatures only would get you nowhere.
The major cities of the Pacific Northwest sit to the West of the Cascades. Looking at the map, it’s clear that the built-up metro areas of Seattle, Victoria, and Vancouver are warmer than the surrounding region. The Cascades are also clearly visible on the map, with the cooler mountains and hotter valleys.
But it’s when you get east of the mountains where the air and ground temperatures truly heat up. That region is cut off from the Pacific Ocean that acts as a moderating influence on air temperatures. Lytton, a small town in the interior of British Columbia, set an all-time Canadian heat record on Monday (breaking the record it set on Sunday). But the smaller city of Kamloops, located about 100 kilometres to the northeast, saw ground temperatures that were even hotter. Again, the town of roughly 90,000 is much more populated than Lytton, and that extra concrete helped ensure ground temperatures were higher. The Sentinel-3 data shows that it reached 56 degrees Celsius there.
In the interior part of Washingon, a similar pattern played out with even more extreme ground temperatures. A large swath of the state saw them reach 55 degrees Celsius or greater, including the aforementioned 63-degree-Celsius reading in Wenatchee.
This type of extreme ground heat isn’t just an eye-popping novelty; it can cause real damage. Roadways have buckled across the Northwest. It also poses a major public health risk. Earlier this month, doctors at the Arizona Burn Centre released a report called “Streets of Fire,” which details the dangers of pavement burns. The findings show that a record 104 heat-related burn injuries showed up at the centre last year. Most were older than 60 years old, and falls were a source of a number of pavement burns.
These weren’t just the kinds of injuries you can slap a bandage on and send folks on their way; rather, patients required an average of two surgeries and a two-week stay at the hospital for recovery. It, unfortunately, goes to show that the climate crisis is making even the ground we walk on a threat to our very existence.