Tag Archives: cities

Unseasonable temperatures? Why your city may be the culprit

The National Center for Atmospheric Research (NCAR) and The University Corporation for Atmospheric Research (UCAR) recently featured an article about a new study in Nature Climate Change that is making us sweat (in February).

The findings suggest that waste heat, produced in urban areas of the Northern developed world as a result of heating, cooling and transportation systems, is impacting our regional weather patterns by changing the nature of our atmospheric systems.

Some Northern Hemisphere regions have had more warming during the winter months than climate models had predicted. Waste heat may be at least part of the explanation for this phenomenon. However, the temperature effects vary depending on the place, ranging between +/- 1°C, and the effects radiate geographically from the urban centers for thousands of miles.

“The burning of fossil fuel not only emits greenhouse gases but also directly affects temperatures because of heat that escapes from sources like buildings and cars,” NCAR researcher and co-author Aixue Hu explains. “Although much of this waste heat is concentrated in large cities, it can change atmospheric patterns in a way that raises or lowers temperatures across considerable distances” (NCAR).

It is important to distinguish these findings from the urban heat island effect. The urban heat island effect is a result of the sun’s heat interacting with urban structures on the Earth’s surface, warming the city but not the surrounding areas. The waste heat effect is a result of fossil fuel combustion and impacts temperatures of places far away from the city.

The study, “Energy consumption and the unexplained winter warming over northern Asia and North America,”was done by Guang J. Zhang (University of California San Diego), Ming Cai (Florida State University) and Aixue Hu (NCAR) and was funded by National Science Foundation, the Department of Energy and the National Oceanic and Atmospheric Administration.

Read the full article here