2014 was warmest year on record for much of Alaska
- Author:
- Updated: May 31
- Published January 5, 2015
On a day when many Interior Alaska towns and villages watch temperatures approach minus 40 degrees and Anchorage nearly dips to zero, it may seem counterintuitive to discuss warmth in the 49th state.
However, what transpired in 2014 is already the subject of considerable discussion among climate scientists. Over the weekend, the National Weather Service in Alaska noted that a number of cities across the state with long-term record keeping saw their warmest year on record in 2014.
Nearly every station west of a line from Anchorage to McGrath to Barrow observed its first-, second- or third-warmest year on record.
McGrath, Kotzebue, Nome, Bethel, King Salmon, Cold Bay and Homer all finished 2014 in first place. Anchorage just missed.
Even in the eastern Interior and Southeast, every major Alaska station except Annette Island saw a top-10-warmest year.
With so many places at or near the top of their all-time temperature lists, was 2014 the warmest year in Alaska since record-keeping began? Surprisingly, a simple question is difficult to answer.
With 663,267 square miles, Alaska is a big place with a lot of open space. Accurate temperature measurements are often difficult to obtain for large portions of the state. Prior to the 1950s, temperature stations were few and far between and filling in the gaps between those isolated stations is full of pitfalls.
Nevertheless, those limited readings provide valuable insight into the prevailing temperatures, and they are a strong indication of whether cold or warm patterns are present. This station-level climate record shows that 2014 is at the top of the list of warmest years since the 1920s. Other contenders are 1926, 1940 and 1993.
When limiting the analysis to first-order -- or major -- stations, we start in 1953, the first year with complete data for all stations. Using only these major stations (Anchorage, Fairbanks, Juneau, Barrow, etc.), 2014 replaced 1993 as the warmest year on record.
Another method of computing statewide averages was recently developed at the University of Alaska's Geophysical Institute in collaboration with the National Weather Service. They divided the state into homogeneous climate regions and computed an average temperature for each of the 13 regions.
A preliminary analysis using their methodology has 2014 in second place behind 1940, a finding that may change as more data arrives at the National Climate Data Center.
One of the truly remarkable climate products produced by the National Oceanic and Atmospheric Administration is called the ESRL 20th Century Reanalysis, which uses a combination of surface observations, ship reports, sea ice measurements, weather balloons and other data to construct a global climate history going back to 1871. Their analysis, while admittedly rough, shows no year in that time period as warm as 2014 for Alaska.
Finally, if we go above ground level, we can see how temperatures look without urban infrastructure or changing terrain. Thirteen stations across the state have released balloons twice a day since 1948. At various intervals above the surface, they gather temperature, moisture, wind and pressure information. The balloon data reveals that 2014 reported the highest average temperature at all levels of the atmosphere below approximately 10,000 feet.
So was 2014 the warmest year on record in Alaska? The National Climate Data Center will make the final determination but it appears that 2014 has a legitimate claim on that title.
And what does a warm 2014 tell us about temperatures for this year? Not much. Alaska has been in a warm phase since approximately 1977. The odds are against setting an all-time record two years in a row but we should expect the climate of 2015 to be significantly warmer than the climate of the first part of the 20th century.
Brian Brettschneider is an Anchorage-based environmental planner and climatologist who writes an Alaska weather blog.
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