Project Funding: 2015 - 2019

NRA: 2014 NASA: Terrestrial Ecology   

Funded by NASA

Abstract:
Vast stores of carbon are sequestered in the permafrost soils, peatlands and boreal forests of western North America. Dramatic increases in warming, permafrost thaw, fire severity and frequency, and other natural disturbances threaten to alter these Arctic-boreal ecosystems (ABEs) irreversibly, transforming the landscape and the ecosystem carbon balance as terrestrial carbon pools are released as atmospheric carbon dioxide (CO2) and methane (CH4). Ecosystem dynamics in the ABR vary on meter scales due to microtopographic changes in permafrost, elevation, water table height, vegetation, microbial populations, etc., resulting in CO2 and CH4 fluxes that vary by orders of magnitude on these scales. It remains unclear how landscape scale processes and biogeochemical drivers impact meso- to regional scale C fluxes or how diurnal to interannual variability of C exchange impacts decadal scale ABE C balance. What is the C balance of the ABoVE domain now and in the future? Are C flux scaling properties constant across the ABoVE domain, or do they vary with ecosystem classification? What emergent properties or macroscopic variables characterize ABE C fluxes at intermediate space-time scales? We will deliver accurate, validated atmospheric CO2, CH4 and CO observations for 2015 - 2019 from the critically located CRV tower in Fox AK, as well as geostatistical inverse model analyses that leverage recent atmospheric observations to evaluate the process level representation of land-atmosphere carbon exchange inside terrestrial biospheric models (TBMs) and identify the environmental parameters that optimally explain the observed spatiotemporal variability in carbon flux patterns across the ABoVE domain. We will work directly with collaborators Potter (CASA), Kimball (TCF), Koven (CLM), Luus (PVPRM) and Bloom (CARDOMAM) to assist them in interpreting our evaluations to improve the performance of their TBMs for ABoVE ecosystems. Our results will significantly reduce uncertainties in estimates of the current carbon balance of ABoVE ABEs and in TBM projections of its future trajectory. Our research 1) Provides a baseline record of atmospheric observations, carbon flux patterns and magnitudes that can be used to document change in the future, 2) Improves our ability to estimate regional scale carbon fluxes and their drivers, and 3) Informs decision making and ecosystem services management through reduced uncertainty in projections of long-term change in ABE carbon balance. We address the ABoVE science question: How are the magnitudes, fates, and land-atmosphere exchanges of carbon pools responding to environmental change, and what are the biogeochemical mechanisms driving these changes?

Publications:

Elder, C. D., Thompson, D. R., Thorpe, A. K., Hanke, P., Walter Anthony, K. M., Miller, C. E. 2020. Airborne Mapping Reveals Emergent Power Law of Arctic Methane Emissions. Geophysical Research Letters. 47(3). DOI: 10.1029/2019GL085707

Parazoo, N. C., Koven, C. D., Lawrence, D. M., Romanovsky, V., Miller, C. E. 2018. Detecting the permafrost carbon feedback: talik formation and increased cold-season respiration as precursors to sink-to-source transitions. The Cryosphere. 12(1), 123-144. DOI: 10.5194/tc-12-123-2018

Potter, C. 2018. Ecosystem carbon emissions from 2015 forest fires in interior Alaska. Carbon Balance and Management. 13(1). DOI: 10.1186/s13021-017-0090-0

Potter, C. 2018. Recovery Rates of Wetland Vegetation Greenness in Severely Burned Ecosystems of Alaska Derived from Satellite Image Analysis. Remote Sensing. 10(9), 1456. DOI: 10.3390/rs10091456

Potter, C. 2019. Changes in Vegetation Cover of the Arctic National Wildlife Refuge Estimated from MODIS Greenness Trends, 2000-18. Earth Interactions. 23(4), 1-18. DOI: 10.1175/EI-D-18-0018.1

Potter, C. 2020. Changes in Growing Season Phenology Following Wildfires in Alaska. Remote Sensing in Earth Systems Sciences. 3(1-2), 95-109. DOI: 10.1007/s41976-020-00038-7

Potter, C. 2020. Changes in Vegetation Cover of Yukon River Drainages in Interior Alaska: Estimated from MODIS Greenness Trends, 2000 to 2018. Northwest Science. 94(2). DOI: 10.3955/046.094.0206

Potter, C., Alexander, O. 2019. Changes in vegetation cover and snowmelt timing in the Noatak National Preserve of Northwestern Alaska estimated from MODIS and Landsat satellite image analysis. European Journal of Remote Sensing. 52(1), 542-556. DOI: 10.1080/22797254.2019.1689852

Potter, C., Alexander, O. 2020. Changes in Vegetation Phenology and Productivity in Alaska Over the Past Two Decades. Remote Sensing. 12(10), 1546. DOI: 10.3390/rs12101546

Potter, C., Hugny, C. 2018. Wildfire effects on permafrost and soil moisture in spruce forests of Interior Alaska. Journal of Forestry Research. 31(2), 553-563. DOI: 10.1007/s11676-018-0831-2

Walter Anthony, K., Schneider von Deimling, T., Nitze, I., Frolking, S., Emond, A., Daanen, R., Anthony, P., Lindgren, P., Jones, B., Grosse, G. 2018. 21st-century modeled permafrost carbon emissions accelerated by abrupt thaw beneath lakes. Nature Communications. 9(1). DOI: 10.1038/s41467-018-05738-9

Yi Y, Kimball J S, Chen R H, Moghaddam M, Miller C E. 2019 Sensitivity of active-layer freezing process to snow cover in Arctic Alaska. The Cryosphere. 13(1), 197-218. DOI: 10.5194/tc-13-197-2019

More details may be found in the following project profile(s):

• NASA Terrestrial Ecology (TE) Project Profile
• North American Carbon Program (NACP) Project Profile
• NASA Arctic-Boreal Vulnerability Experiment (ABoVE) Project Profile