The NPS along with other Federal and State agencies in Alaska are partnering in a multi-year multi-million-dollar mapping initiative to update topographic (elevation) information for the entire State. During the past several years, 5-m IFSAR elevation data have been acquired over approximately 34% of Alaska, including 43% (23.7 million acres) of NPS lands. In 2012 the NPS received its first delivery of the new airborne IFSAR elevation data, which included coverage of Mt.
Tidewater glaciers are a prominent feature along the southeastern and south-central coasts of Alaska and play an important role in landscape and ecosystem processes.
The topography of many Alaskan national parks has changed greatly over the last 50 years primarily because of glacier retreat and downwasting (thinning). Glaciers have downwasted as much as 640 m and retreated up to 17 km. Previous researchers developed a technique that determined glacier volume changes in southeast Alaska by comparing elevation data from the 1950s with data from the 2000 Shuttle Radar Topography Mission (SRTM) DEM. The Denali National Park and Preserve and the vast majority of Wrangell-St.
In 2012, GPS and GIS remote sensing technologies were vital tools used for resource management in Kenai Fjords National Park (KEFJ). As part of an ongoing glacier monitoring effort, KEFJ staff used Trimble GPS to navigate to and update mass balance stake locations and to assess flow velocity of the Harding Icefield (see figure below showing Harding Icefield).
The Great Smoky Mountains National Park is collecting light detection and ranging (lidar) data in partnership with the State of North Carolina and the U.S. Geological Survey (USGS) to develop high-precision terrain models, forest canopy metrics, and terrain derivatives such as slope, ruggedness, and prominence. These products have proven to be mission-critical with regard to hydrologic modeling and landslide detection.
The lowlands of the NPS ARCN, like much of the arctic and subarctic, have extensive areas of lakes and ponds. According to the National Hydrography Dataset (USGS NHD 2012) there are approximately 1,090 km² of surface water in lakes and ponds in ARCN. The area of lakes and ponds in some parts of Alaska has declined in recent decades. Whether these changes represent long-term trends or are merely cycles that will eventually reverse is important to consider. Water bodies are important both as habitat for aquatic wildlife and as indicators of changes in the hydrologic balance.
Snow cover plays a major role in the energy and freshwater balances of Alaska, and variability in snow cover extent and duration are climatologically important. The Southwest Alaska Network Inventory and Monitoring Program is working with the Geographic Information Network of Alaska at the University of Alaska Fairbanks to develop historical snow cover metrics (dates of first and last snow) for Alaska. An algorithm was developed to derive these metrics for the period 2001-2012 using the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra daily snow cover product (MOD10A1).
Vegetation ecologists within the National Park Service Arctic and Southwest Alaska Inventory & Monitoring (I&M) Networks, along with researchers at the University of Alaska Fairbanks Geographic Information Network of Alaska (GINA), have developed an algorithm to derive Normalized Difference Vegetation Index (NDVI) growing season metrics for Alaska using satellite data from MODIS.
The NPS Alaska regional compliance team frequently uses aerial photography and satellite imagery to convey resource conditions and locations to the public in National Environmental Policy Act (NEPA) documents. These images accurately portray the lay of the land and affected resources, and the reviewers find the data rich and aesthetic. Satellite imagery has been used in conjunction with wetlands field data for a proposed access road through a sensitive area to a new barge landing location near Brooks Camp in Katmai National Park.
The Alaska Shallow Lake Monitoring Program monitors the water quantity, water chemistry, littoral vegetation community composition, and macroinvertebrate communities of shallow lakes in the Arctic (ARCN) and Central Alaska (CAKN) Networks of the National Park Service Inventory and Monitoring Program.