Organization: National Aeronautics and Space Administration (NASA)

Research Title: Geodynamics and Geopotential Fields

Funding Level (millions of dollars):

FY94 28.2
FY95 15.2
FY96 7.6

Committee on Environment and Natural Resources (CENR) Component:
(a) Subcommittee: Global Change Research Subcommittee (50%) Natural Disaster Reduction Research Subcommittee(50%) Task Group on Observations and Data Management
(b) Environmental Issue: Scientific and technical advances to reduce vulnerability (40%) Natural variability, including seasonal-to-interannual forecasting and past changes in climate (20%) Global Change: exploratory research into systematic changes in the dynamics of the crustal, atmospheric, and oceanic circulation (20%); Loss reduction measures and mitigation (10%); Other (10%)
(c) Research Activity System structure and function Observations (20%); Understanding (50%); Assessments - Risk Assessment (30%)

Organizational Component:
Solid Earth Branch
Science Division
Office of Mission to Planet Earth
NASA Headquarters
Washington DC 20546

Point of Contact:
Miriam Baltuck
Phone: 202-358-0273
E-Mail: mbaltuck@hq.nasa.gov

Research Goals:
To observe and understand the dynamics of the solid Earth and its interaction with the atmosphere and hydrosphere with a focus on those short and long term processes responsible for natural hazards, global change, and the distribution of natural resources.

Research Description:
The Geodynamics Program pursues its research goal by providing national and international leadership in the development of new technologies, the coordination of observations, and the development of theoretical models.

Support the operation of global and regional geodetic systems for monitoring solid earth, oceanic, and atmospheric dynamics. The Geodynamics program supports a strong international observation program through its Fiducial Laboratories for International Natural science Network [FLINN] and the International Geodetic GPS Service (IGS) of global geodetic observatories. The observatories utilize Global Positioning System (GPS), Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) technologies. The Geodynamics Program collaborates with the USN, NOAA and agencies of over forty-five countries in the operation of the geodetic networks. These networks provide for monitoring millimeter scale motions of the global tectonic plate system and its seismically active plate boundaries. Because of continuing improvements in measurement accuracy, the systems are beginning to accurately track the effects of atmospheric and oceanic circulation on earth rotation and gravity. The GPS and SLR networks provide sub-decimeter scale precision orbit determination of altimetry and gravity satellites in order to monitor seasonal and long term global change.

Develop technologies to achieve the basic research goal of understanding geodynamics: The program supports cutting edge research in the development of geodetic, gravity and magnetic measurement technologies to determine Earth structure and to monitor earth dynamics. The NASA program has improved the GPS, VLBI, and SLR geodetic technologies by three orders of magnitude, with at least one additional order of magnitude improvement expected within the decade. Continuing improvements in geodetic technology have significantly improved the utility of the geodetic networks for natural hazards mitigation and the study of global climate change. The program supports the development of medium and short baseline GPS arrays and associated technologies to monitor and mitigate seismic and volcanic hazards in regions such as the Los Angeles metropolitan area. The program also supports the development of technologies such as GPS satellite occultation to better characterize the variability of temperature and water vapor in the atmosphere, which are sources of noise in geodetic measurements and very important parameters in global climate research.

Observe, understand and predict the dynamics and evolution of the Earth's lithosphere in order to mitigate the danger of earthquakes, understand land subsidence, locate and access natural resources: The Geodynamics Program supports GPS field campaigns along active plate boundaries such as the San Andreas fault, the Alaskan trench system, and the Andean and Himalayan mountain ranges. The goal is to develop a better understanding of the seismic potential and the development of natural resources at active plate boundaries. The Program supports this strong observational program with theoretical studies of earthquake rupture, lithospheric and mantle structure and rheology in order to better understand the observed phenomena.

Program Interfaces:
The Geodynamics Program is part of the Solid Earth Program, the goal of which is improve understanding of the evolution, structure, and dynamics of the Earth through measurement and analysis of space-based geodetic, remote sensing, space-based geopotential, field, laboratory, and related data. This is part of NASA's Mission to Planet Earth to better understand the Earth as a system, the global environment and how it is changing. The program is responsive to the U.S. Global Change Research Program and coordinates with other federal agencies, through the Committee on Environment and Natural Resources (CENR) Subcommittee on Natural Disaster Reduction, including DOD. Internationally, the program is responsive to the International Decade of Natural Disaster Reduction, participates in the US/Japan Science and Technology Agreement, and coordinates research and development with 45 countries, worldwide.

Program Milestones:

Policy Payoffs: