B42A-08
The NASA Soil Moisture Active Passive (SMAP) Mission Level 4 Carbon Product calibration and validation using eddy covariance observations across North America, Australia and Finland
Thursday, 17 December 2015: 12:05
2006 (Moscone West)
E. Natasha Stavros1, John S Kimball2, Lucas A Jones2, Andreas Colliander1, Joseph M Glassy3, Rolf H Reichle4, David Schimel5, Dennis D Baldocchi6, Jason Beringer7, James R Cleverly8, Ankur R Desai9, Eugenie Susanne Euskirchen10, Lindsay B Hutley11, Peter Robert Isaac12, Beverly Elizabeth Law13, Craig Macfarlane14, Walter C Oechel15, Suzanne M. Prober16, Pullianinen Jouni, Russell L Scott18, Howard S. Wheater19 and Donatella Zona15, (1)NASA Jet Propulsion Laboratory, Pasadena, CA, United States, (2)University of Montana, Numerical Terradynamic Simulation Group, College of Forestry & Conservation, Missoula, MT, United States, (3)Lupine Logic Inc., Missoula, MT, United States, (4)NASA GSFC, Greenbelt, MD, United States, (5)Jet Propulsion Laboratory, Pasadena, CA, United States, (6)University of California Berkeley, Dept of Environmental Science, Policy, & Management, Berkeley, CA, United States, (7)University of Western Australia, Crawley, WA, Australia, (8)University of Technology Sydney, Ultimo, Australia, (9)University of Wisconsin Madison, Madison, WI, United States, (10)University of Alaska Fairbanks, Fairbanks, AK, United States, (11)Charles Darwin University, Casuarina, NT, Australia, (12)Monash University, Melbourne, Australia, (13)Oregon State University, Corvallis, OR, United States, (14)CSIRO Land and Water Flagship, Private Bag No. 5, Wembley,WA6917, Australia, (15)San Diego State University, San Diego, CA, United States, (16)CSIRO Land and Water Flagship, Wembley, WA, Australia, (17)Agricultural Research Service Tucson, Tucson, AZ, United States, (18)University of Saskatchewan, Global Institute for Water Security, Saskatoon, SK, Canada
Abstract:
The NASA SMAP (Soil Moisture Active Passive) mission was successfully launched January 31st 2015, inaugurating global operational low frequency (L-band) microwave observations of land surface soil moisture and freeze-thaw dynamics with 3-day mean temporal fidelity. The novelty of SMAP is in the high quality of the geophysical observations, global monitoring of dynamic landscape freeze-thaw (FT) and soil moisture (SM) conditions, and the model-enhanced estimation of root zone soil moisture (0-100 cm) and terrestrial carbon fluxes (constrained by environmental controls). The SMAP Level 4 Carbon Product (L4_C) uses lower-level geophysical data to constrain estimates of terrestrial net CO2 exchange and addresses a key science objective of the SMAP mission, which is to understand processes that link the terrestrial water, energy and carbon cycles, particularly in boreal landscapes. Here we present the L4_C calibration and validation infrastructure, which uses eddy covariance tower flux observations. A metric of L4_C product success is to estimate NEE in northern (≥45°N) boreal and arctic biomes to within 30 gCm-2yr-1 or ~1.6 gCm-2 d-1 RMSE, similar to the level of uncertainty for tower observations. We present initial L4_C product comparisons against independent observations from a global network of 33 in situ tower sites, 8 of which are considered primary sites in the high latitudes (≥45°N). Although only primary sites are used to determine product success, all sites are integrated into diagnostic plots to evaluate land cover heterogeneity between local tower footprints and overlying L4_C grid cells, algorithm handling and data quality, thus providing a framework for evaluating environmental constraints on ecosystem productivity and respiration. In addition to mission success, we examine the added value of including FT and SM to constrain terrestrial carbon flux estimates.
