Project Information

Title: LTM Program: Long-term Monitoring of Oceanographic Conditions in the Alaska Coastal Current from Hydrographic Station GAK-1 20120114-I

Project Year and Number: 2020: 20120114-I

Other Fiscal Years and Numbers for this Project: 2024: 24120114-I , 2023: 23120114-I , 2022: 22120114-I , 2021: 21120114-I, 2019: 19120114-I, 2018: 18120114-I, 2017: 17120114-I, 2016: 16120114-P, 2015: 15120114-P, 2014: 14120114-P, 2013: 13120114-P, 2012: 12120114-P

Principal Investigator (PI): Seth Danielson (University of Alaska Fairbanks)

Managing Agency: NOAA

Assisting Personnel: Tom Weingartner (University of Alaska Fairbanks)

Project Website: https://gulfwatchalaska.org/monitoring/environmental-drivers/gulf-of-alaska-mooring-gak1-monitoring/

Research Location: Gulf of Alaska, Prince William Sound

Restoration Category: Monitoring

Injured Resources Addressed: Not Specified

Abstract:

This project continues a nearly half-century time-series of temperature and salinity measurements at hydrographic station GAK-1. With first sampling in 1970, the data set consists of nominally monthly conductivity-temperature versus depth casts and a mooring outfitted with seven temperature/conductivity recorders distributed throughout the water column and a fluorometer at 20 m depth. The project monitors five important Alaska Coastal Current (ACC) ecosystem parameters that quantify and help us understand hourly to seasonal, interannual, and multi-decadal period variability in: 1) temperature and salinity throughout the 250 m-deep water column, 2) near surface stratification, 3) surface pressure fluctuations, 4) fluorescence as an index of phytoplankton biomass, and 5) along-shelf transport in the ACC. All of these parameters are basic descriptors that characterize the workings of the inner shelf and the ACC, an important habitat and migratory corridor for organisms inhabiting the northern Gulf of Alaska, including Prince William Sound, and resources injured by the Exxon Valdez oil spill. We are aware of over 90 publications utilizing data collected at station GAK-1, and since 2000 the citation list has grown by nearly three publications per year. These publications range from physical, chemical and biological oceanography to climate studies, fisheries research, fisheries management applications, and ecosystem-based management applications. We report that recent water temperatures remain warmer than the long-term average throughout the water column, while near-surface waters have freshened over time and near-bottom waters have salinized. We document an increase of stratification that carries important and far-reaching implications for ecosystem dynamics. We are not proposing any major changes to this project in FY20.


Proposal: View (881 KB)

Reports:
Annual Report: View (1,835 KB)
Final Report: See Project 21120114-I

Publications from this Project: None Available