Continuous Monitoring of Physical Parameters in Southwest Alaska Lakes - Claudette Moore , NPS (co-authors: Jeff Shearer, Aquatic Ecologist, NPS- SWAN)

ABSTRACT

The Southwest Alaska Network (SWAN) park units include some of the largest and most pristine freshwater resources in the National Park System. Despite the remote, wilderness nature of these lake systems, they are subject to large-scale anthropogenic and natural influences including climate change, volcanic activity and fluctuating glacial runoff. These influences have the potential to impact physical lake characteristics that drive biological indicators critical to lake productivity.

In order to partially fulfill water quality monitoring objectives, SWAN deployed a moored temperature array to monitor water temperature, light intensity and lake level year-round in Lake Clark in 2006. Additional arrays were deployed in Naknek Lake and Lake Clark in 2008 and 2009, respectively, with additional deployments planned for Lakes Kontrashibuna and Brooks in 2010. These lakes were identified as high priority lakes for monitoring, collectively representing glacial /non-glacial and anadromous / non-anadromous systems. Data from these continuously operating stationary sites combined with observations derived from vertical lake profiles provide the spatial and temporal reference that, over time, will allow us to estimate inter-annual variability and detect trends for physical lake characteristics including: ice freeze-up / break-up, lake stratification, thermocline development and movement of sediment plumes.

Three years of data reveal some striking examples of how quickly these large lakes respond to environmental change. When integrated with emerging data from other Vital Signs including landscape processes, glacial extent and climate / weather, we can begin to assess cause and effect relationships across the landscape and quantify changes within these lake systems.

Additional Info: Claudette Moore and Jeff Shearer for the Southwest Alaska Inventory and Monitring Program.

Topic: Watershed monitoring