2019 Gulf of Alaska Ecosystem Status Report: In Brief
The Gulf of Alaska experienced unusually warm conditions in 2019. This followed the extreme marine heatwave of 2014–2016 (known popularly as “The Blob”) and a return to more typical temperatures during 2017 and 2018.
In September 2018, sea surface temperatures in the western Gulf of Alaska shelf area crossed a temperature threshold to become a marine heatwave and have largely remained in heatwave status since then.
Sea level pressure patterns from late 2018 through summer 2019 resulted in high pressure over the Gulf of Alaska, which suppressed storminess and contributed to the development of warm sea surface temperatures, particularly during the summer. Sea surface temperatures were similar to those during the previous 2014–2016 “Blob” heatwave. While the total number of days in heatwave status during 2019 was similar to that during 2015, there was proportionally more heat during this past summer. These warm temperatures extended down into the water column, especially in the western Gulf of Alaska. The weather in the coastal Gulf of Alaska also featured warmer than normal air temperatures and lower than usual precipitation, leading to drought conditions in areas accustomed to summer rain.