Endless Summer? Northern Hemispheric Summers Are Getting Longer

A hot summer day in Burlingon, Vermont a couple years
ago. Recent studies say climate change is making summers
 longer than they used to be in the Northern Hemisphere 

We can't exactly say summer is here in Vermont quite yet. For us, it's still early spring. Even so, some of that warm weather in late March had us wondering. 

Itt turns out, though, that summer in general is getting longer not just here, but across most of the Northern Hemisphere. 

That's not just the perception of yours truly, who is of that opinion that those lazy, hazy, crazy days of summer are increasing in number here in Vermont. 

Scientists who look at this sort of thing have come to the same conclusion. A study on the subject recently came out. 

According to The Hill/Changing America:

"Published in the journal of Geophysical Research and letters, the study looks at climate and seasonal data spanning 1952 to 2011 in the Northern Hemisphere. Collecting temperatures data over these years helped scientists track when each of the four seasons began on average.

The results indicate that the average duration of summer increased from an average of 78 days to 95, while spring, winter, and fall all saw decreases in length ranging from three on nine days. 

Extrapolating this data, scientists found that if this trend continues at the current rate, summer could last nearly six months by 2100."

Of course, I guess it all depends on how you define summer.  Eighty degrees in the South is early spring.  Seventy degrees here qualifies for some around here as summer. In any event, whether it's 70 or 80 or 90, those types of days are coming earlier. 

In any event, this earlier summer news is regarded as mostly bad, as does most things that have to do with climate change

Places that already have long, hot summers will get even hotter for longer periods of time, exposing more people to heat related illnesses and deaths. Mosquitoes could invade more northern climates. Malaria could head north into places where it isn't a problem now. 

Sounds lovely, huh?

Also, the seasons are getting more fickle, with more out-of-season warm spells that can screw around with crops, especially if a seasonable freeze follows. 

A classic, destructive example of this is going on in western and central Europe right now. Many areas there had their hottest temperatures on record for the month of March.  Everything's blooming, including fruit trees and other crops. 

Now, a record cold Arctic blast is sweeping into Europe this week with snowstorms and temperatures plunging into the low and mid teens Fahrenheit in some areas.  Widespread crop, fruit tree and garden damage is happening now across western Europe. 

This heat to freeze scenario has been happening in the United States as well. 

A prime example is a long-lasting March, 2012 heat wave in the eastern two thirds of the United States and southeastern Canada (including here in Vermont).

The spell of summer-like weather caused plants and trees to sprout, only to have them freeze when the normal frosts of April arrived. This caused huge amounts of fruit tree damage from Michigan to Georgia

In the United States, a similar but somewhat less intense March warm spell this year than in 2012 has probably already created the same situation this year.  Widespread freeze warnings went up across most of the southeastern United States late last week amid a cold spell. Fruit trees were certainly damaged in some areas.

Much less importantly, but a real-world example came for me in my own St. Albans, Vermont gardens.  Some of my daffodils were almost ready to bloom, when the late snow and cold spell made in.  

The situation made for pretty snow on flower photos, but the cold might have killed some of the flower bulbs. (They might survive because I frantically covered them with thick layers of mulch, we'll see).

The cold snap was not abnormal for this time of year. But the March warmth that prompted the garden flower plants surely was.

A few back yard daffodils in Vermont aren't the most important thing in the world. But food crops are. 

Scientists are studying how these shifting seasons are affecting crops.  As NBC points out, climate change affects not just where particular crops grow, but how well they do in any given place. 

It's all in the timing. Flowers and pollinators have evolved to have a schedule such that they work well together. Mess with the timing of the seasons, and you mess with this flower/pollinator coordination.

Scott Sheridan, a climate scientist at Kent State University, told NBC the "never-ending summer" study illustrate how humans, other animals, plants and the environment are interconnected. "Shifting seasons can wreak a lot more havoc than you think when you realize all the systems that are tuned to the timing of the seasons," he said.