The Yukon River basin encompasses 832,000 square-kilometers and is one of Earth's largest boreal-Arctic rivers. Characterized by a long, frozen winter season, the river demonstrates an abrupt ice breakup and spring snowmelt-driven flood pulse.
The snow season has become shorter and the growing season longer over the past 20 years in Alaska's Arctic National Parks. The NPS Arctic Inventory and Monitoring Network (ARCN) uses MODIS (Moderate Resolution Imaging Spectroradiometer) satellite images and remote automated cameras to monitor the timing of the growing season and the snow cover in five large national parks in northern Alaska.
Twenty years ago, ecological studies were often limited by the number of times biologists could find (relocate) their study animals. With the advent and now widespread use of Global Positioning System (GPS)collars, tracking the animals is no longer a primary concern.