Monitoring Arctic and boreal ecosystems through the assimilation of field-based studies, remote sensing, and modelling Active
Northern high-latitude regions are experiencing climate warming at rates nearly double that of lower latitudes, leading to warming and thawing of permafrost-affected soils, decomposition of previously frozen organic matter and increases in the number of large fire years, which can substantially impact social and environmental systems. Monitoring Arctic and boreal ecosystems of northern latitudes is challenging because of the high costs of conducting remote field work across these vast and heterogenous landscapes. Researchers at the Earth Resources Observation and Science (EROS) Center, in collaboration with academic and federal partners, conduct studies that leverage field research, remote sensing, and modelling to better characterize Arctic and boreal ecosystem conditions and properties (e.g. permafrost, vegetation productivity, structure and composition, Earth surface dynamics), thereby improving our knowledge and understanding of how and why permafrost-affected landscapes are changing.
Neal Pastick (KBRwyle) documenting coastal erosion along Alaska’s Arctic coastline near the village of Kaktovik. (Credit: M. Torre Jorgenson)
Media Highlights
Our team’s research has been featured in a number of public media venues, including Scientific America, the Guardian, the New York Times, the Washington Post, and others. Below are a few recent examples.
The following is a brief overview of focal areas of EROS’ research on Arctic and boreal landscapes in Alaska:
Permafrost characterization:
Permafrost – permanently frozen ground – is estimated to underly nearly a quarter of the northern circumpolar and is vulnerable to thaw with continued climate warming. Changes in permafrost distribution can impact ecological, hydrological and topographical conditions, thereby disrupting communities, infrastructure, and fish and wildlife populations. Permafrost is difficult to monitor and map, however, because it is a subsurface phenomenon that is typically covered by surface organic material (e.g. vegetation). To address ecological and spatial complexities inherent when characterizing permafrost-affected soils, our team leverages state-of-the-art modelling tools and remote sensing data to extend geophysical surveys to the larger landscape. Our quantitative modeling approaches have enabled a new generation of permafrost maps and techniques needed by land resource managers and modelers to better understand Alaska’s changing landscape.
Land and surface-water dynamics:
Terrestrial and aquatic ecosystem modelling provides a means for documenting and understanding historical and potential ecosystem changes in the face of climate warming. Our studies on land and surface waters range in scope from modelling and mapping of terrestrial biomass, which is a key biophysical parameter in the studies of Alaska's ecosystems, to the quantification of ecological, hydrological, and geomorphological change using remote sensing and process-based models. By incorporating field and geospatial data into modeling frameworks, we continue to investigate the interconnected responses in vegetation productivity, composition, surface-water dynamics and disturbances to climate warming. Current work addresses the characterization and implications of earth-surface dynamics on permafrost-affected landscapes and communities, including thermokarst, lacustrine dynamics, wildfire, and erosion and deposition.
Funding
This research has been funded by the U.S. Geological Survey Land Change Science, Biological Sequestration (LandCarbon), National Research, and Climate Land Use Research and Development Programs, as well as NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE) and the Fish & Wildlife Service.
Below are publications associated with this project.
The role of driving factors in historical and projected carbon dynamics of upland ecosystems in Alaska
Distribution and landscape controls of organic layer thickness and carbon within the Alaskan Yukon River Basin
Extending airborne electromagnetic surveys for regional active layer and permafrost mapping with remote sensing and ancillary data, Yukon Flats ecoregion, central Alaska
Towards integration of GLAS data into a national fuels mapping program
Establishing water body areal extent trends in interior Alaska from multi-temporal Landsat data
A multi-sensor lidar, multi-spectral and multi-angular approach for mapping canopy height in boreal forest regions
Estimating aboveground biomass in interior Alaska with Landsat data and field measurements
MODIS-informed greenness responsesto daytime land surface temperaturefluctuations and wildfire disturbancesin the Alaskan Yukon River Basin
Airborne electromagnetic imaging of discontinuous permafrost
A Comparative Analysis of three different MODIS NDVI data sets for Alaska and adjacent Canada
Integrating modelling and remote sensing to identify ecosystem performance anomalies in the boreal forest, Yukon River Basin, Alaska
Below are news stories associated with this project.
New Study Provides the First Comprehensive, Long-term Look at Alaska’s Changing Ecosystems
New research has revealed significant changes to Alaska’s landscape in recent decades
- Overview
Northern high-latitude regions are experiencing climate warming at rates nearly double that of lower latitudes, leading to warming and thawing of permafrost-affected soils, decomposition of previously frozen organic matter and increases in the number of large fire years, which can substantially impact social and environmental systems. Monitoring Arctic and boreal ecosystems of northern latitudes is challenging because of the high costs of conducting remote field work across these vast and heterogenous landscapes. Researchers at the Earth Resources Observation and Science (EROS) Center, in collaboration with academic and federal partners, conduct studies that leverage field research, remote sensing, and modelling to better characterize Arctic and boreal ecosystem conditions and properties (e.g. permafrost, vegetation productivity, structure and composition, Earth surface dynamics), thereby improving our knowledge and understanding of how and why permafrost-affected landscapes are changing.
Neal Pastick (KBRwyle) documenting coastal erosion along Alaska’s Arctic coastline near the village of Kaktovik. (Credit: M. Torre Jorgenson)
Media HighlightsOur team’s research has been featured in a number of public media venues, including Scientific America, the Guardian, the New York Times, the Washington Post, and others. Below are a few recent examples.
The following is a brief overview of focal areas of EROS’ research on Arctic and boreal landscapes in Alaska:
Permafrost characterization:
Permafrost – permanently frozen ground – is estimated to underly nearly a quarter of the northern circumpolar and is vulnerable to thaw with continued climate warming. Changes in permafrost distribution can impact ecological, hydrological and topographical conditions, thereby disrupting communities, infrastructure, and fish and wildlife populations. Permafrost is difficult to monitor and map, however, because it is a subsurface phenomenon that is typically covered by surface organic material (e.g. vegetation). To address ecological and spatial complexities inherent when characterizing permafrost-affected soils, our team leverages state-of-the-art modelling tools and remote sensing data to extend geophysical surveys to the larger landscape. Our quantitative modeling approaches have enabled a new generation of permafrost maps and techniques needed by land resource managers and modelers to better understand Alaska’s changing landscape.
Land and surface-water dynamics:
Terrestrial and aquatic ecosystem modelling provides a means for documenting and understanding historical and potential ecosystem changes in the face of climate warming. Our studies on land and surface waters range in scope from modelling and mapping of terrestrial biomass, which is a key biophysical parameter in the studies of Alaska's ecosystems, to the quantification of ecological, hydrological, and geomorphological change using remote sensing and process-based models. By incorporating field and geospatial data into modeling frameworks, we continue to investigate the interconnected responses in vegetation productivity, composition, surface-water dynamics and disturbances to climate warming. Current work addresses the characterization and implications of earth-surface dynamics on permafrost-affected landscapes and communities, including thermokarst, lacustrine dynamics, wildfire, and erosion and deposition.
Funding
This research has been funded by the U.S. Geological Survey Land Change Science, Biological Sequestration (LandCarbon), National Research, and Climate Land Use Research and Development Programs, as well as NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE) and the Fish & Wildlife Service.
- Publications
Below are publications associated with this project.
The role of driving factors in historical and projected carbon dynamics of upland ecosystems in Alaska
It is important to understand how upland ecosystems of Alaska, which are estimated to occupy 84% of the state (i.e., 1,237,774 km2), are influencing and will influence state‐wide carbon (C) dynamics in the face of ongoing climate change. We coupled fire disturbance and biogeochemical models to assess the relative effects of changing atmospheric carbon dioxide (CO2), climate, logging and fire regimAuthorsHélène Genet, Yujie He, Zhou Lyu, A. David McGuire, Qianlai Zhuang, Joy S. Clein, David D'Amore, Alec Bennett, Amy Breen, Frances Biles, Eugénie S. Euskirchen, Kristofer Johnson, Tom Kurkowski, Svetlana (Kushch) Schroder, Neal J. Pastick, T. Scott Rupp, Bruce K. Wylie, Yujin Zhang, Xiaoping Zhou, Zhiliang ZhuFilter Total Items: 22Distribution and landscape controls of organic layer thickness and carbon within the Alaskan Yukon River Basin
Understanding of the organic layer thickness (OLT) and organic layer carbon (OLC) stocks in subarctic ecosystems is critical due to their importance in the global carbon cycle. Moreover, post-fire OLT provides an indicator of long-term successional trajectories and permafrost susceptibility to thaw. To these ends, we 1) mapped OLT and associated uncertainty at 30 m resolution in the Yukon River BaAuthorsNeal J. Pastick, Matthew B. Rigge, Bruce K. Wylie, M. Torre Jorgenson, Joshua R. Rose, Kristofer D. Johnson, Lei JiExtending airborne electromagnetic surveys for regional active layer and permafrost mapping with remote sensing and ancillary data, Yukon Flats ecoregion, central Alaska
Machine-learning regression tree models were used to extrapolate airborne electromagnetic resistivity data collected along flight lines in the Yukon Flats Ecoregion, central Alaska, for regional mapping of permafrost. This method of extrapolation (r = 0.86) used subsurface resistivity, Landsat Thematic Mapper (TM) at-sensor reflectance, thermal, TM-derived spectral indices, digital elevation modelAuthorsNeal J. Pastick, M. Torre Jorgenson, Bruce K. Wylie, Burke J. Minsley, Lei Ji, Michelle Ann Walvoord, Bruce D. Smith, Jared D. Abraham, Joshua R. RoseTowards integration of GLAS data into a national fuels mapping program
Comprehensive canopy structure and fuel data are critical for understanding and modeling wildland fire. The LANDFIRE project produces such data nationwide based on a collection of field observations, Landsat imagery, and other geospatial data. Where field data are not available, alternate strategies are being investigated. In this study, vegetation structure data available from GLAS were used to fAuthorsBirgit E. Peterson, Kurtis Nelson, Bruce WylieEstablishing water body areal extent trends in interior Alaska from multi-temporal Landsat data
An accurate approach is needed for monitoring, quantifying and understanding surface water variability due to climate change. Separating inter- and intra-annual variances from longer-term shifts in surface water extents due to contemporary climate warming requires repeat measurements spanning a several-decade period. Here, we show that trends developed from multi-date measurements of the extents oAuthorsJennifer R. Rover, Lei Ji, Bruce K. Wylie, Larry L. TieszenA multi-sensor lidar, multi-spectral and multi-angular approach for mapping canopy height in boreal forest regions
Spatially explicit representations of vegetation canopy height over large regions are necessary for a wide variety of inventory, monitoring, and modeling activities. Although airborne lidar data has been successfully used to develop vegetation canopy height maps in many regions, for vast, sparsely populated regions such as the boreal forest biome, airborne lidar is not widely available. An alternaAuthorsDavid J. Selkowitz, Gordon Green, Birgit E. Peterson, Bruce WylieEstimating aboveground biomass in interior Alaska with Landsat data and field measurements
Terrestrial plant biomass is a key biophysical parameter required for understanding ecological systems in Alaska. An accurate estimation of biomass at a regional scale provides an important data input for ecological modeling in this region. In this study, we created an aboveground biomass (AGB) map at 30-m resolution for the Yukon Flats ecoregion of interior Alaska using Landsat data and field meaAuthorsLei Ji, Bruce K. Wylie, Dana R. Nossov, Birgit E. Peterson, Mark P. Waldrop, Jack W. McFarland, Jennifer R. Rover, Teresa N. HollingsworthMODIS-informed greenness responsesto daytime land surface temperaturefluctuations and wildfire disturbancesin the Alaskan Yukon River Basin
Pronounced climate warming and increased wildfire disturbances are known to modify forest composition and control the evolution of the boreal ecosystem over the Yukon River Basin (YRB) in interior Alaska. In this study, we evaluate the post-fire green-up rate using the normalized difference vegetation index (NDVI) derived from 250 m 7 day eMODIS (an alternative and application-ready type of ModeraAuthorsZhengxi Tan, Shu-Guang Liu, Calli B. Jenkerson, Jennifer Oeding, Bruce K. Wylie, Jennifer R. Rover, Claudia J. YoungAirborne electromagnetic imaging of discontinuous permafrost
The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost in relation to surface and groundwaterAuthorsB. J. Minsley, J.D. Abraham, B. D. Smith, J. C. Cannia, C.I. Voss, M.T. Jorgenson, Michelle Ann Walvoord, B.K. Wylie, L. Anderson, L.B. Ball, M. Deszcz-Pan, T.P. Wellman, T. A. AgerA Comparative Analysis of three different MODIS NDVI data sets for Alaska and adjacent Canada
No abstract available.AuthorsLei Ji, Bruce K. Wylie, Bhaskar Ramachandran, Calli B. JenkersonIntegrating modelling and remote sensing to identify ecosystem performance anomalies in the boreal forest, Yukon River Basin, Alaska
High-latitude ecosystems are exposed to more pronounced warming effects than other parts of the globe. We develop a technique to monitor ecological changes in a way that distinguishes climate influences from disturbances. In this study, we account for climatic influences on Alaskan boreal forest performance with a data-driven model. We defined ecosystem performance anomalies (EPA) using the residuAuthorsB.K. Wylie, L. Zhang, Norman B. Bliss, Lei Ji, Larry L. Tieszen, W. M. Jolly - News
Below are news stories associated with this project.
New Study Provides the First Comprehensive, Long-term Look at Alaska’s Changing Ecosystems
New research has revealed significant changes to Alaska’s landscape in recent decades