Chilly Spring Around Here Is A Global Exception

Most of the world, with the exception of much of Canada and half
the United States was warm in April. It will be regarded as the
second warmest April on record for the world as a whole. 

It was another frosty morning in Vermont, the last of a string of them.

The warming trend has arrived in the Green Mountain State. But of course, this being 2020, it turns out the warming might be tamped down a bit by a stalled area of low pressure along the East Coast next week.

We'll see about that, but at least it won't be cold anymore. No more frosts, no more snow

While we here in the Northeast shivered through large chunks of April and the first half of May, the rest of the world broiled.

Global numbers for April are in and it was more or less tied for the hottest April on record, at least on a global basis.

NOAA's Centers for Environmental Information place April, 2020 as the second hottest on record, just an itty bitty skosh cooler than the record holder, April, 2016. Other measurements call last month THE hottest. All measurements basically come up with the same numbers for the month.

Central and eastern Canada, and the northeastern third of the United States were practically the only cool spots in the world during April.

As Bob Henson in Weather Underground's Category 6 blog points out, there were areas of incredible heat this past April.

Kyrgyzstan, China and Mongolia all set all time records for April heat.  Unseasonable wildfires ripped through eastern Siberia. Cuba reported all time record high temperatures, not just for April, but for the entire year. Southern Florida wilted in June-like heat.

The global temperature trends make it all but certain this year will globally be one of the top five warmest on record.

By the way, there is no discernable impact on carbon dioxide in the atmosphere now that much of the world's economy is shut down by Covid-19.  We are still spewing enough carbon dioxide into the atmosphere to increase concentrations of this main greenhouse gas.  It's just that the rate at which it's increasing in the atmosphere has probably slowed, for now at least.

Discover Magazine notes that atmospheric carbon dioxide concentrations, as measured on top of Hawaii's Mauna Loa reached an all time high of 416.82 parts per million in April, which exceeds the previous high in April, 2019.  For a variety of reasons, carbon dioxide concentrations in the air cycle yearly, with an annual peak in April.

The International Energy Agency expects global carbon dioxide emissions to decrease by 8 percent this year, not enough, really, to significantly alter the forward path of climate change. Scientists are conducting flights around major cities along the East Coast to further study how these Covid shutdowns are affecting carbon emissions.

One intriguing thing to watch: Particulate polllution has decreased with these Covid-19 economic shutdowns. These little particles block a little bit of sunshine from getting through which has had the effect of tempering climate change a bit.

Will this year be hotter globally because of reduced particulate pollution, with more sun getting through?   Scientists are interested in finding out more, that's for sure.