U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            REICHLE, R - NASA GSFCitem
                                            BOSILOVICH, M - NASA GSFCitem
                                            Crow, Wadeitem
                                            KOSTER, R - NASA GSFCitem
                                            KUMAR, S - NASA HDBitem
                                            MAHANAMA, S - NASA GSFCitem
                                            ZAITCHIK, B - NASA GSFC
  Submitted to: Book Chapter
                                    Publication Type: Book / Chapter
                                    Publication Acceptance Date: 4/1/2008
                                    Publication  Date: 3/9/2009
                                    Citation: Reichle, R.H., Bosilovich, M.G., Crow, W.T., Koster, R.D., Kumar, S.V., Mahanama, S.P., Zaitchik, B.F. 2009. Recent advances in land data assimilation at the NASA Global Modeling and Assimilation Office. In: Pard, S.K., editor. Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications. London, United Kingdom: Springer-Verland. p. 407-428.Interpretive Summary: Data assimilation systems are powerful tools for optimally combining information gleaned from a variety of sources – including remote sensing data obtained from spaceborne sensors.  This manuscript provides a review of recent land data assimilation advances made through a collaboration between USDA ARS HRSL scientists and researchers at the Global Modeling and Data Assimilation Office at NASA Goddard Space Flight center.  The review article describes a number of new data assimilation advances and contributions to state of the art coupled land-atmosphere modleing.  The eventual application of these techniques may enhance our ability to make long-term weather and climate forecasts within agricultural regions.
                                Technical Abstract: Research in land surface data assimilation has grown rapidly over the last decade.  We provide a brief overview of key research contributions by the NASA Global Modeling and Assimilation Office (GMAO).  The GMAO contributions primarily include the continued development and application of the Ensemble Kalman filter (EnKF) for land data assimilation.  In particular, we developed a method to generate perturbation fields that are correlated in space, time, and across variables and that permit the flexible modeling of errors in land surface models and observations, along with an adaptive filtering approach that estimates observation and model error input parameters.  A percentile-based scaling method that addresses soil moisture biases in model and observational estimates opened the path to the successful application of land data assimilation to satellite retrievals of surface soil moisture.  Assimilation of such data into the ensemble-based GMAO land data assimilation system (GMAO-LDAS) provided superior surface and root zone assimilation products (when validated against in situ measurements and compared to the model estimates or satellite observations alone).  Satellite-based terrestrial water storage observations were also successfully assimilated into the GMAO-LDAS.  Furthermore, synthetic experiments with the GMAO-LDAS support the design of a future satellite-based soil moisture observing system.  Satellite-based land surface temperature (LST) observations were assimilated into a GMAO heritage variational assimilation system outfitted with a bias estimation module that was specifically designed for LST assimilation.  The on-going integration of GMAO land assimilation modules into the Land Information System will enable the use of GMAO software with a variety of land models and make it accessible to the research community.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov