Here’s a little food for thought especially considering this warm week, with overall temperatures on the rise, what is considered normal will be changing. NOAA, the National Oceanic and Atmospheric Administration, publishes climatological normals or averages every decade based on 30-year average temperatures. The most recent normals are based on the average temperatures from 1981-2010. Click here to find the daily normals for Nashville and some other locations in Tennessee. Here is one of the graphics you can generate at the link.
The folks at Climate Central did something a little different with the numbers. They calculated a 30-year average ending each year from 1980 to 2015. For example, the normal temperature for 1980 in this analysis was based on the average temperature from 1951-1980, and the 2015 normal is the average from 1986-2015. As you can see from the graphic they created for Nashville shows what is normal has been warming.
As a matter of fact, out of the 135 locations analyzed in the Climate Matters network, 97% of them had a higher 30-year average temperature in 2015 versus 1980. Many have seen an additional increase in their averages since the last NOAA analysis of 1981-2010. Here’s the national map. It illustrates that national trend of warming.
So what does this mean? According to Climate Central, “The shift in long term averages has resulted in the longer growing season in most of the country, with temperatures starting to remain consistently above freezing earlier in the year, and staying above freezing until later in the year. Some plant and animal species are starting to migrate northward or upward in elevation as a result, meaning a variety of pests and weeds are now found in places previously too cold for them to live.”
This warming trends may not look like a big deal now. It does have a ripple effect. More extreme heat will likely mean more heat-related illness such as heat stroke. More hot days means more air conditioning which will likely stress the nation’s aging electrical grid and drive up costs.
Oh and there’s the change in our winters. Winters have been warming more rapidly than summers. That may sound good to some folks, but the future effects of excessive summer heat are expected to far outweigh the benefits of milder winters.
With that in mind…what younger generations consider very warm today may seem especially hot to their grandparents.
That’s the climate story, I’ll have the weather story of this hot week coming up on Channel 4 News at 10pm.