Mainstream media report that July was the “hottest” month since 1880 (or as CNN wrongly reported, “ever”). And future Julys will only become hotter.
But July temperature anomalies (departures from the 1981-2010 average in degrees Celsius) presented in the accompanying chart show the claim is false, according to the University of Alabama in Huntsville satellite data for the entire period.
So July 2016 isn’t the warmest July on record, even stretching back only to 1979. The record month was July 1998 — in a year made abnormally warm by the same thing that’s making 2016 abnormally warm, an abnormally strong El Nino.
Nonetheless, I don’t care whether July 2016 was the warmest month since the 1880s, because it doesn’t matter. Why?
First, since the early 1800s the world has been rising out of the Little Ice Age. When you ascend to a plateau, your altitude (or, in this case, temperature) will stay at or around that plateau until you either resume ascending or begin descending. So record highs are no big surprise.
Second, the margin by which July 2016 is warmer (a more realistic term than “hotter”) than the near runners-up is so tiny as to be irrelevant to any life on Earth.
Third, the spread between “hottest” and “coldest” Julys in the satellite record is 1.2 degrees Celsius. I dare you to find someone who will step from a room at 15 degrees Celsius (59 degrees Fahrenheit) to a room at 16.1 degrees Celsius (60.98 degrees Fahrenheit) and, unrehearsed, say “Ugh, this room is hotter!” (as distinct from mildly warmer). So much of this controversy is rooted in overblown rhetoric.
Fourth, the difference between July 2016 (0.39 degrees Celsius) and the next-hottest July (2010) is only 0.06 degrees Celsius. That’s indiscernible to humans and within the measurement margin of error for the globe.
Ah, but future Julys will only become hotter, some might argue.
Maybe, maybe not. Nobody knows what future temperatures will be. Even the Intergovernmental Panel on Climate Change said in its Third Assessment Report, “The climate system is a coupled non-linear chaotic system, and therefore the long-term prediction of future climate states is not possible.”
For it to be true that “future Julys will only become hotter,” the annual ups and downs evidenced in the 37-year satellite record will have to stop. Not only that, but also there will be no more “little ice ages” driven by solar minimums, or glacial periods driven by Milankovich cycles, or any other such thing. How likely do you think that is?
How does July’s “record heat” fit into global temperature history?
It depends on the period. You’ve got the entire satellite record for Julys included, and you can see for yourself: It’s hardly significant. For the land and sea surface temperature record back to 1880, sure, maybe it’s warmer, by perhaps 1 degree Celsius, than at the start of the period. So what? Temperature changes by 10 or 20 times that on any given day and by 60 to 80 times that from winter low to summer high in many locales around the world.
Since the end of the last glacial period (18,000 years ago), last month was much warmer than at the start (thank God!), but much cooler than the Holocene Climate Optimum (9,000-5,000 years ago), probably cooler than the Minoan (3,000 years ago) and Roman (2,000 years ago) warm periods, and almost certainly cooler than the Medieval Warm Period (950-1250 A.D.).
Finally, in the debate over the magnitude of the human contribution to global warming, July’s warmth is utterly irrelevant. A 0.06 degrees Celsius difference is a 0.06 degrees Celsius difference, whether caused by turning on an electric stove burner a half-second ago, by natural solar and ocean cycles over thousands or millions of years, or by adding carbon dioxide to the atmosphere for the last two centuries.
So cool it. Don’t get sucked in by the rhetorical hype. Enjoy a lemonade, hug your kids, and get on with life.
Originally published at the Washington Times.