DISCUSSION: Air temperatures are warming about twice as fast near the poles than the global average rise. The associated rise in ocean temperatures can impact the environment in many different ways. The valuable ecosystems and fisheries in the waters around Alaska are especially vulnerable to warming ocean temperatures. The figure above shows sea surface temperature anomalies (degrees Celsius) valid for 12 May 2017. Much of the coastal waters of Alaska and along the Aleutian Islands are abnormally warm, some areas by as much as ~4 degrees C. One impact of these warm waters is on Arctic cod, a fatty fish that is especially important for the food web near Alaska and people. Research has shown that in warmer waters, Arctic cod eggs are less likely to survive and hatch properly. Instead the warmer waters are more favorable for such species as Pacific cod and walleye pollock, fish that are less fatty and provide fewer calories to whales and other animals that eat them. Other research suggests that in years with abnormally warm springs when sea ice retreats early, krill abundance declines. Krill also serves as important food source for the marine ecosystem near Alaska. Another impact of warmer ocean temperatures may be more frequent algal blooms, some of which may emit toxins that are dangerous to mammals and birds. Thus, warmer ocean temperatures can influence ecosystems in various ways, many of which are not beneficial. For more information on the impacts of warmer ocean temperatures near Alaska, please see the story posted by Alaska Dispatch Publishing.
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©2017 Meteorologist Dr. Ken Leppert II