America’s Winter Of 1979

By Paul Homewood

 

 

We often hear the claim that more high temperature records are set than low ones in the US, and that this somehow proves the climate is warming. As the Guardian reported last year

In a long-term trend that demonstrates the effects of a warming climate, daily record-high temperatures have recently been outpacing daily record-lows by an average of 2-to-1, and this imbalance is expected to grow as the climate continues to warm. According to a 2009 study, if the climate were not warming, this ratio would be expected to be even.

 

I have already shown that nearly all of the high records have been set at stations that don’t date back to the 1920’s and 30’s, when the vast majority of record temperatures were set. But critics say “ what about the lack of cold records?”. As the Guardian tries to argue, surely the ratio of hot to cold should be even?

 

To answer this question, you need to look back to the 1960’s and 70’s. To qualify as a record, the station concerned needs at least 30 years of data. This means that virtually all stations date back to 1979, and the vast majority were certainly operational prior to 1970.

Why is this important? Because the 1960-79 period was a much colder interlude, both compared with the years before and after. The graph below shows the trend of winter temperatures in the USA. Not only were most winters colder than previously during these years, but 1979 was exceptionally so. Indeed it was by far the coldest on record.

 

http://www.ncdc.noaa.gov/cag/

 

Not only was the winter of 1978/9 so cold, the cold was widespread across the country.

 

http://gis.ncdc.noaa.gov/map/cag/#app=cdo

 

So it comes as little surprise that relatively few low temperature records have been set in recent years. You might just as well measure temperatures from January to July, and wonder why there are no days in July setting cold records.

It is also worth noting that it was not just the USA that was cold that winter, as this GISS map illustrates. Note that the anomaly is set against a baseline of 1951-80, not the last 30 years.

 

http://data.giss.nasa.gov/cgi-bin/gistemp/nmaps.cgi?year_last=2013&month_last=6&sat=4&sst=3&type=anoms&mean_gen=1203&year1=1979&year2=1979&base1=1951&base2=1980&radius=1200&pol=reg

 

And, of course, it is 1979 that began using satellites to monitor global temperatures and sea ice extent!