UAF Researchers Montior Gulf of Alaska and Find Waters Warmer

Oct 20, 2014

Scientists at the University of Alaska Fairbanks have been studying the waters in the Gulf of Alaska and found that the warmer than normal temperatures are averaging one to five degrees warmer than the September average of 55-57 degrees Fahrenheit.

Researchers pull in a CTD – an instrument that collects high resolution temperature and salinity data throughout the water column.
Credit University of Alaska Fairbanks

The Seward Line is the long-term monitoring site in the Gulf of Alaska.  It helps scientists understand the details of what is happening in the waters over the Alaska shelf.

Professor at UAF Russ Hopcroft is the chief scientist studying the waters.  He says his group is studying and monitoring the waters in the Gulf because, just like on land, fluctuating temperatures have interesting and possibly influencing affects.

“The oceans are just like land in the sense that we have years that are hot or cold.  And we know that when we have unusually hot or cold season on land that animals or plants are often stressed by those conditions and don’t do well and then everything that depends on them has a good or a bad year.”

Warmer temperatures along the Seward Line are partly a result of an unusual winter that left the Gulf’s offshore waters warmer than normal.  Hopcroft says his group goes out in early May each year since 1997 to run a series of stations from the mouth of Resurrection Bay to 40 miles off the edge of the shelf. 

“Take samples for water physics, the temperatures, the solidity, and optical properties, how light travels through it, monitor ocean acidification, look at the biomass at the plant plankton that is there, the phytoplankton, and collect the animal plankton, the small animals that are food for many fish and marine animals in this region.  And lastly we actually have someone that does an inventory of the seabirds and animals that we encounter while we’re doing our work.”

The group uses technologies that include satellites that track the development of these warm waters, fixed buoys suited with instruments and biological and chemical samples taken from ships. 

Hopcroft says the group looks at the samples of phytoplankton to get an idea of how the biological world will be effected by the warmer temperatures.

“Because when we look quickly at the plankton samples that we’ve collected, we can see we have an unusually high number of species that we normally have in the lower 48 as opposed to Alaska.  We don’t have the quantitative numbers on that because there’s several months of analysis required to get all that data out of that plankton samples because a person has to look for several hours at each sample in their microscope.”

He says the scientists will know soon if the warmer temperatures this year are a onetime phenomenon or a permanent progression.