Saturday, March 8, 2014

Heating Degree Days Increasing in US

An interesting trend is occurring in the United States in Heating Degree Days, HDD.  The much-discussed "Pause" in global average surface temperature corresponds to an increase of 20 HDD per year.  

HDD are described in the Energy Information Agency's page as: 

"A degree-day compares the outdoor temperature to a standard of 65°F; the more extreme the temperature, the higher the degree-day number and the more energy needed for space heating or cooling.

. . . Cold days are measured in heating degree-days. For a day with a mean temperature of 40°F, 25 heating degree-days would be recorded. Two such cold days would result in a total of 50 heating degree-days for the two-day period."

Data since 1998 to 2011 for HDD in the US showing increasing trend of 20 HDD per year. 

It is unfortunate that the EIA data stops at 2011. (as of this writing, March 2014).  The winters of 2011-2012, 2012-2013, and 2013-2014 should be added to the data.  This current winter, 2013-2014, will likely have much higher than average HDD due to the multiple cold waves that swept the nation.  

HDD can be used as an objective measure, independent of the agenda-driven warming alarmists, to determine the direction and extent of climate change.  From the above graph, it is clear that HDD are increasing.  

This bears close watching. 

Roger E. Sowell, Esq.
Marina del Rey, California.  

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