Temperatures and Water Levels at Tanana Flats Monitoring Stations

• Main Authors: Ferrick, Michael G., Racine, Charles H., Reidsma, Steven, Saari, Stephanie P., Gelvin, Arthur B., Collins, Charles M., Larsen, Gary
• Other Authors: ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
• Format: Text
• Language: English
• Published: 2008
• Subjects: Meteorology; Hydrology; Limnology and Potamology; *ATMOSPHERIC TEMPERATURE; *GROUND WATER; STATIONS; LEVEL(QUANTITY); BOATS; PERMAFROST; WATER RECLAMATION; SUMMER; WETLANDS; ALASKA; *AIRBOATS; TANANA FLATS; permafrost; Alaska
• Online Access: http://www.dtic.mil/docs/citations/ADA480744; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA480744

A network of data recording stations has been progressively deployed over recent years in the Tanana Flats to better understand the hydrology of the wetlands and the hydrologic impacts of airboat use. All stations monitor logger temperature, water soil temperature profiles, and water levels. The logger temperatures at each station accurately represent local air temperatures. Winter conditions contribute significantly to fen temperature extremes the following summer, and conversely, the thermal storage in the fen in the summer is important to temperature conditions the following winter. The water level data provided overall ranges for each fen and indicated a typical annual cycle. Slow recession occurs during the cold late fall and winter months as a result of groundwater outflow, and spring melt is a time of recharge and general water level recovery. Water levels in May through October vary significantly between years, depending on rainfall. Hydrologic deficits that develop in dry years can be eliminated by 1 2 wet months. Conversely, several consecutive large rains can cause high fen water levels. Surface outflows diminish as water levels fall, and moderate levels are sustained by normal rainfall. Data from the station pair at Birch Island Well Murphy Fen indicate a direct connection throughout the year between water beneath the permafrost and that in the nearby fens. Representative stations in each fen were selected to use for management of airboat access according to local water levels. Staff gauges that can be monitored by web cameras were installed at each of these stations in August 2007. The harsh environment, remote locations, and limited opportunities for access to the stations have often interrupted the continuity of data records. As a result, hydrologic issues remain to be resolved that will require continued station maintenance and operation. The original document contains color images.