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Vital Pacific Ocean Climatology Updated

Version 2 of the Northern North Pacific Regional Climatology released

Spatial coverage of the Northern North Pacific Regional Climatology.
Courtesy of NCEI

The Pacific Ocean usually brings to mind tropical islands and warm trade winds. It’s easy to forget about the Northern North Pacific, where the Pacific’s icy waters become the Arctic Ocean. And while this part of the Pacific Ocean may be frigid, it is also full of life—from whales to deep sea corals.  

Researchers have been collecting information about this important ecosystem for decades. NCEI just updated its Northern North Pacific (NNP) Regional Climatology. The NNP Regional Climatology Version 2 is based on more than 70 years of observations, and incorporates a significant amount of data not previously available to the public.

What is a Climatology?

According to the World Meteorological Organization, the term “climatology” defines long-term averages of a given variable, usually temperature, over various time periods. In oceanography, the term “ocean climate” is used to define ocean parameters averaged over a decade or longer.  

A monthly decadal ocean climatology, for example, will provide a value for each month averaged over the selected decade. Ocean climatologies, global or regional, relate specifically to long-term averaged oceanic parameters—for example, temperature, salinity, oxygen, etc., in the entire World Ocean or in selected ocean regions.

NCEI develops improved ocean climatologies for annual, seasonal, and monthly periods to perform scientific analyses, while investigating interannual-to-decadal ocean climate variability using historical oceanographic data.

Supporting the Blue Economy

NNP Regional Climatology Version 2 is based on the World Ocean Database 2023 and includes a large volume of new data that enables a more detailed, up-to-date version since the last version was published over a decade ago. The NNP Regional Climatology consists of a set of analyzed temperature and salinity fields computed on a high-resolution spatial grid to assess long-term climatological tendencies in this important region. There are seven different decadal climatologies, starting with 1955–1964 and ending with 2015–2022. 

Millions of television viewers have followed crab fishermen aboard fishing vessels in these cold waters during Alaskan king crab and snow crab seasons. The Northern North Pacific is made up of some of the most productive fisheries in the world, including the Gulf of Alaska, Bering Sea, Aleutian Islands, and Beaufort Sea. The state of Alaska produces more than half the fish caught in waters off the coast of the United States, with an average wholesale value of nearly $4.5 billion a year. 

The region has been under stress in recent years, however, with the Alaska snow crab fishery closing for the first time in history in 2022 due to a sudden mass mortality event. NOAA Fisheries scientists identified that the most likely cause of the decline was starvation and other factors linked to the 2018–19 marine heatwave (NOAA Fisheries October 19, 2023). Departures from previous observations can only be seen by knowing what those previous observations are, and that is why regional climatologies are important. 

The new high-resolution temperature and salinity decadal climatologies will allow researchers to more precisely assess decadal climate change in the Northern North Pacific, substantially increasing this climatology’s value for ocean climate studies and other applications. This update will improve understanding of the most recent ocean climate change in this region.