Any weather anomaly in our nation’s capital acquires cosmic significance. A heavy snowstorm in January, 1996 made the cover Newsweek, which blamed global warming. It was world news when three big snowstorms hit in the winter of 2009-10. Climate alarmists again said they were caused by pernicious economic activity. Flatliners said they were evidence of global cooling … and so it goes.
The National Weather Service is currently forecasting 103 degrees for Friday with a dewpoint of 72, which gives a “heat index” (a rough measure of physiological heat stress) of 116, hard into the “danger zone” for prolonged exposure or strenuous physical activity. As of now, that looks like the crest of this heatwave.
The cynics among us will point out that this is really pretty much a garden‐variety peak‐of‐summer hot spell, and yes, we brought it upon ourselves by building dreaded cities, and that it has been much worse before “climate change” ever became an epithet. Further, what we are seeing is minor, weenie, dinky — compared to the great eastern heatwave of July and August 1930.
To see the real magnitude of the heat, check out the 1930 temperatures far away from DC’s urban core. Down at McCormick Observatory in Charlottesville, which has several hundred feet of elevation on Washington (and therefore should be a couple of degrees cooler), the daily highs, beginning on July 19, were 103, 107, 106, 105, 97, 92, 102, 104, 93, 103, 106, 90, 95, 91, 97, 101, 106, 102, 90, 100, 99, 105 and 98.
DC’s residents poured out of their ovens and set up quarters on the Mall and in Rock Creek Park. Minnesota congressman Charles Davis died of heatstroke. About half of Virginia’s counties reported shortages of drinking water. Baptisms were suspended. 30 rattlesnakes ravaged a farm in Michigan, attacking turkeys for their blood. 300,000 acres of forest combusted in Virginia (the current annual average is around 10,000). Smoke + sunlight = ozone, making the air in 1930 truly vile.
Downtown, the Washington Post maintained an accurate thermometer in a newspaper kiosk, where the shade temperatures reached 110 on July 20 and August 9. Reasonably assuming a 72 degree dewpoint yields a heat index of 124. But Washington has warmed further since then from its urban heat island, so a downtown temperature/heat index of 113 and 127 would likely occur today under the meteorological conditions of 1930. About these nosebleed temperatures we’re suffering in the Distric, almost all of Washington’s summer warming is due to the city itself rather than to global change — summer high temperatures in nearby rural Virginia show no significant trend whatsoever.
I have noted in previous columns that heat‐related deaths are indeed declining in every large U.S. urban area with the exception of cool Seattle. As urban heat becomes common, we adapt.
But there’s one scary aspect: we are now dependent upon air conditioning. It used to be that the first heatwaves of summer produced disproportionate mortality, and then, as people got used to the heat, a similar warm spell killed fewer. We have probably lost some of our ability to acclimate because of our technology.
Loss of air conditioning creates big problems, this proven in the great Midwestern heatwave of 1995 (when the heat index reached a deadly 136 in southern Wisconsin). When Chicago bakes, there’s always more mortality on the poorer South Side, where many older buildings lack air conditioning. In 1995, that wasn’t the case, as a dry thunderstorm knocked out power early in the heatwave in the air‐conditioned North Side, spreading mortality equally on both sides of the city.
Both extremely hot and cold temperatures stress our electrical grid to the breaking point, and there is precious little in reserve. Frigid winds in 1994 caused rolling brownouts in the East. A major power catastrophe was narrowly averted in 1999 when a brief but very intense heat pulse fortunately occurred on the Fourth of July. What will happen on the East Coast when the weather of 1930 repeats itself, as it surely will?
We simply haven’t tested our power supply under such conditions, and we really don’t have an infrastructure that can cope with such an event. While current heat in the eastern U.S. shouldn’t cause any major power problems, it will certainly be used to draw Washington’s attention to climate change. Perhaps we should be worrying instead about our electricity supply. Meanwhile, a repetition of 1930 awaits.