Research Title: Climates of Arid/Semi-Arid Regions
Funding Level (millions of dollars):
Committee on Environment and Natural Resources (CENR) Component:
(a) Subcommittee: Global Change Subcommittee (100%)
(b) Environmental Issue: Natural Variability (42%), Large-scale Land Use Changes (29%), Climate Change (29%)
(c) Research Activity: System structure and function: Understanding (50%), Observation (8%); Assessment (20%); Data Management (22%)
U.S. Geological Survey
104 National Center
Reston, VA 22092
Point of Contact:
This program addresses concerns regarding the response of climatically sensitive regions to climate change and human activities.
USGS efforts are done in collaboration with investigators at NASA, NOAA, USDA, DOD (US Army) and several universities, including the University of Nevada and University of New Mexico.
This program supports studies 1) to improve understanding of the relationship between climate, surficial processes, and vegetation cover in arid and semi-arid regions or in regions susceptible to future aridification, and 2) to define the extent and timing of past desertification. Activities are focused on regions in the central and southwestern US and involve investigations of soils, wind-blown deposits, fluvial processes, and desert land forms. Landsat imagery, airborne imagery, and radar are used in conjunction with ground-based studies and automated monitoring stations to inventory and monitor ongoing surficial processes, such as wind erosion, dust storms, and changes in vegetation and soils in response to short term climate change. Human populations and activities have expanded dramatically into arid and semi-arid regions of the US and other areas of the world. The resulting changes in land use patterns, vegetation, and ecosystem disturbance, susceptibility of soils to wind erosion, and increased demands on water supplies are problems that could become even greater with changing climates.
Accomplishments include documenting the extent of wind-blown deposits in the central US, thus defining areas that are highly susceptible to wind erosion under current or slightly dryer conditions. In addition 5 "GEOMET" desert climate monitoring stations in 5 different types of deserts in Arizona and New Mexico have been established. These stations monitor climate change, surficial processes, and vegetation changes.
FY 1994: Complete report outlining major wind-blown sand transport events and intervals in the central US during last 10,000 years FY 1994: Complete digital shaded relief map of the western US (west of 100th meridian) as a base for mapping land surfaces that are highly susceptible to wind erosion. FY 1995: Incorporate GEOMET data into modeling wind velocity thresholds for different land surfaces, including variations in sediment type and vegetation cover. Data and reports are peer reviewed and results are published in USGS reports or scientific journals. This program is reviewed annually by an external panel of specialists from universities and other government agencies, and their recommendations are used to make program adjustments.
Documentation of current and past interaction between surficial processes and climate variation in arid and semi-arid regions will allow identification of changes that are caused by human activities, and provide better estimates of the effects of anticipated future changes. Identification of areas that are most susceptible to minor changes in climate or human activities will directly impact land use decisions.