A new study examining how energy use can influence local climates found temperature changes in Britain and Japan are better explained by energy use than by climate models.
“Our results are strong evidence that changes in energy consumption contribute to temperature change over sub-decadal timescales in the two nations considered,” two British scientists wrote in their study that was recently accepted by the journal Earth’s Future.
“Britain has experienced a drop in temperature of about 0°.5 C since the early years of the millennium at a time when world temperatures have remained virtually stable,” the study’s authors wrote, “whereas Japan experienced a rise in [temperature of] 1°.0 C between the early 1980s and 2000, double the world rise in temperature over the same period.”
“Both these changes reflect changes in energy consumption in each country,” the authors wrote.
Britain and Japan are both highly urbanized islands that use lots of energy, so scientists wanted to see if using more energy for things like heating and air conditioning could be influencing their climates.
For years, climate scientists have known cities tend to give off more heat than surrounding areas, therefore artificially increasing the temperature. This is called an “urban heat island” and even NASA and NOAA correct for this phenomena when calculating global average temperature.
The question is, just how much these heat centers throw off national, or even global, average temperature estimates. This new study found changes in how much people heat and cool their homes, drive their cars and other activities can raise or lower national temperatures by several tenths of a degree Celsius.
“If projections of energy consumption prove to be true, then future contributions of anthropogenic heat to climate change in Japan and the U.K. will have fallen by 2040,” the authors wrote. “Japan is predicted to have an 18% fall, corresponding to a temperature drop of about 0.3 C, and the U.K. a 3% fall, producing a negligible drop in temperature.”
Meteorologist Anthony Watts has been a major force behind research to show just how much urban heat islands can throw off temperature readings.
Watts released a study in December, which found climate scientists were adjusting temperature data upwards to match “poorly-cited” weather stations tainted by man-made heat sources.