Ongoing and future climate change throughout Alaska has the potential to affect terrestrial ecosystems and the services that they provide to the people of Alaska and the nation. These services include the gathering of food and fiber by Alaskan communities, the importance of ecosystems to recreation, cultural, and spiritual activities of people in Alaska, and the way that land cover and vegetation in ecosystems affect temperature and water flow (runoff, flooding etc.) throughout the state.
Assessments of the effects of climate change on these “ecosystem services” have been hindered by a lack of tools (e.g. computer models) capable of forecasting future landscapes in a changing climate while taking into account numerous other factors such as changing fire patterns, vegetation growth, organic materials in soil, and seasonal thaw of frozen ground. As a response to this need, the Integrated Ecosystem Model (IEM) was designed and developed to help resource managers understand how Alaskan ecosystems will change in the future as our climate changes. The IEM generates maps and other products that illustrate how arctic and boreal landscapes might change in response to other climate change-driven changes in vegetation, hydrology, permafrost (e.g. frozen ground) etc.
The IEM integrates three different models:
- the Alaska Frame-Based Ecosystem Code (ALFRESCO), which simulates wildland fire and vegetation establishment and growth;
- the Geophysical Institute Permafrost Lab model (GIPL), which simulates characteristics of soils, hydrology, vegetation, plant community composition, biomass, and carbon balance in soil;
- and the Terrestrial Ecosystem Model (TEM) [which includes the Dynamic Vegetation (DVM) and Dynamic Organic Soil (DOS) models], which simulates permafrost (i.e. frozen ground) dynamics and changes.
