Urban heat islands exist even in the Arctic

Sunless winter doesn’t prevent warming in cities

polar night

NORTHERN NIGHTS  Researchers ferry weather system sensors to Apatity, a Russian Arctic city. The team’s data show that during the polar night, indoor heating can bleed into the environment, warming it by as much as 10 degrees Celsius relative to nearby rural sites.

M. Varentsov/Lomonosov Moscow State Univ.

TROMSØ, Norway — A novel form of the “urban heat island” effect might contribute to why the far north is warming faster than the rest of the globe, a study of five Arctic cities finds.

Sunlight can heat dense building materials. When night falls, buildings will release some of their solar energy into the air. This helps explain why urban centers tend to be a few degrees warmer than nearby rural areas.

“We decided that our Russian Arctic cities should also show this phenomenon,” says Mikhail Varentsov, a climatologist at Lomonosov Moscow State University. But indoor heating — not the sun — would be the major heat source, at least in winter, when the sun shines little if at all. To test that idea, he and colleagues set up weather stations to collect data in the five

THE HEAT IS ON Even during the polar night, the center of Apatity is warmer (red) than the outskirts of the Russian city. AWS urban is the weather station in the town center.M. Varentsov et al/Lomonosov Moscow State Univ., Russian Academy of Sciences and World Meteorological Org.
largest cities north of the Arctic Circle for about a week during the polar night (with 24 hours of darkness).

Apatity, with a population of about 59,000, showed the strongest effect. Its city center was up to 10 degrees Celsius warmer than outlying areas. Murmansk, with more than 300,000 residents, showed a similar, but smaller, in-town increase of about 3 degrees Celsius. Varentsov shared his team’s findings January 28 at the international Arctic Frontiers conference.

Janet Raloff

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.

More Stories from Science News on Environment

From the Nature Index

Paid Content