Glacier Bay Oceanographic Monitoring Program Analysis of Observations, 1993-2016
Danielson S. 2024. Glacier Bay Oceanographic Monitoring Program Analysis of Observations, 1993-2016. National Park Service
The Glacier Bay oceanographic monitoring data archive period of record (1993-2016) is newly analyzed in this report. As with the preceding report (Danielson 2012) covering 1993-2009, this document serves as a reference manual for thermal and haline oceanic conditions at fixed-location sampling stations throughout the bay. The mean annual cycle is characterized at each station throughout the water column using monthly averages. Monthly climatological hydrographic cross-sections show how the mean water column structure varies along the length of the fjord. Removing the climatology from each station’s individual records generates monthly anomalies that are evaluated for trends and fluctuations occurring over seasonal to inter-annual time scales. The dominant hydrographic signal for the 2010-2016 monitoring time period was a transition from relatively cool waters over 2007-2013 to a 2014-2016 marine heat wave, which drove average water temperatures throughout the bay to approximately 1.5 °C higher than normal. The warming was accompanied by a strong freshening that was equivalent to the addition of 3 km3 of fresh water to the bay, or a continuous excess of 50 m3 s-1 of runoff over two years. Biological consequences of this relatively long-lived warming and freshening are still mostly unknown, but effects may be felt for years to come.
- Type
- Published Report
- Authors
- Danielson, Seth
- Date of Issue
- 2024-12
- Publisher
- National Park Service