Climate Watch: Climate regions

Nome is fortunate to have more than 110 years of weather and climate observations. Of course, Nome is, after all, just one place in western Alaska, and as we all know well, conditions can vary greatly over short distances.

One of the tools that climate scientists use is to look at conditions over larger areas.

However, while regional scale climate information has been available since the 1950s for the Lower 48, there was nothing like it for Alaska.

That changed in 2012 when Peter

Bieniek at the University of Alaska Fairbanks developed a method to create regions of Alaska with broadly similar climate patterns. He found that 13 different regions within Alaska captured most of the monthto-month differences of temperature and precipitation in the state.

One of the regions is aptly named “Western Alaska”, and it runs from north of Kotzebue to the lower Kuskokwim River area.

This came as something of a surprise to me: I thought the Bethel region would be more similar to Bristol Bay, but no, it’s more like areas farther north.

In 2015, Dr. Bieniek’s climate divisions were adopted by NOAA as the official climate regions for

Alaska and now produce temperature and precipitation analysis monthly.

The graphic shows an example of how we can use this information to track what’s happening with parts of the western Alaska environment. The bars show the relative difference from normal for temperatures for each month since January 2011 through November 2019.

From 2011 until mid-2013 there were a number of very cold months in western Alaska, but since then there have been very few months that have been colder than normal by any amount, and relative to normal March and June of this year, along with January 2012 on the cold side, are the most extreme months in the past decade.