Stressors and impacts

Two large tracts of protected land along Alaska’s west coast face increasing threats from climate change. On the Seward Peninsula, the Bering Land Bridge National Preserve is a remnant of the land that once connected Asia with North America. The area is protected for the study of past cultures and to support the traditional lifestyles of current and future residents. North of the Preserve, the linear beach bluffs of Cape Krusenstern National Monument record thousands of years of change in the shorelines of the Chukchi Sea, including archeological evidence of human habitation for the past 9,000 years.

Linear beach ridges near Cape Krusenstern National Monument show evidence of the beach system growing toward the sea over thousands of years. Archeological sites in the region include ancestral villages of the Inupiat people. 

The designation of these lands as National Park Service units in 1980 has provided some protection for their natural and historic properties; however, the coastal lands, their prehistoric secrets, and habitat they provide for fish, plants, and wildlife are threatened by the impacts of climate change. Increasingly warmer conditions in the Arctic have reduced the extent and duration of sea ice in the Chukchi Sea, so the coasts are subject to longer periods without the protection of sea ice. As a result, rising seas, thawing permafrost, and severe storms have accelerated coastal erosion.

As only a small percentage of the coastline along these parks has been studied, potentially valuable sites and resources are likely unknown and unprotected. Without knowledge of what is at stake, resource managers and land stewards cannot make informed decisions that could protect them.

Making plans for monitoring

Together, the Bering Land Bridge National Preserve and Cape Krusenstern National Monument encompass an area nearly the size of Connecticut. In order to preserve their natural and cultural resources, the National Park Service needs baseline information and an inventory of assets that can help them make prudent management decisions. To meet these needs, the National Park Service Arctic Network Inventory and Monitoring Program (ARCN) is developing long-term monitoring protocols to help them compile baseline information and establish effective monitoring programs.

To deal with the extensive area of land they need to study and the difficulty of reaching these remote parks, many researchers turn to remote sensing technologies. For instance, time-series images from satellites are particularly useful in monitoring coastal erosion. Researchers also analyze changes in vegetation and other land surface features using high-resolution aerial photographs—they can analyze the photos to measure parameters such as shrub cover, tree cover, and area of small ponds left behind by thawing permafrost. Taking repeat photographs in the future will give them a way to document visible changes over time. 

Automated cameras at weather stations also provide data on vegetation and snow cover. Photographs from these stations provide a close-up view of changes in the seasons that can be linked directly to weather data.

Monitoring on the ground

Habitats in the coastal zone are critical for bird nesting, seal haul-outs, denning sites, freshwater and anadromous fish (fish, such as salmon, that are born in fresh water, spend most of their lives in the sea, and return to fresh water to spawn), and migratory stopover sites for marine mammals and birds. The coastal zone also supports subsistence fishing, egg gathering, and hunting of waterfowl and marine mammals. Gathering information on these parameters generally requires boots-on-the ground fieldwork.

Members of the Cape Krusenstern crew surveying for returning birds. 

Examples of habitat-monitoring projects planned or underway include post-breeding bird surveys, lagoon water mass budgets, permanent marine debris monitoring sites, and a coastal survey of at-risk cultural sites. Additional projects include determining ecological classifications along the parks’ coasts, an interdisciplinary biophysical baseline assessment of lagoons and estuaries, updating environmental coastal sensitivity indices, and understanding the ecology and seasonal dynamics of whitefish.

Loss of sea ice will also likely increase the ocean exchange with lagoons in the coastal zone, a process that rising sea level will accelerate. Changes in chemical and physical characteristics of lagoon water, such as salinity and hydrodynamics, will alter biological components of the ecosystem in unknown ways. These systems currently provide habitat for globally important populations of birds, including some species that are threatened or endangered. Understanding how these systems are changing is the first step in any effort to promote their resilience.

Using environmental intelligence

Gathering data and establishing long-term monitoring programs in these parks will provide resource managers, land stewards, archeologists, biologists, and subsistence hunters a better understanding of what these parks offer, and how they are threatened by climate change. As the Arctic warms, this basic information will help them understand, prepare for, and respond in ways that promote the preservation, enjoyment, and scientific value of these unique national lands.