The U. S. Geological Survey Chesapeake Bay Science Program
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The San Francisco Bay-Delta estuary and its watershed have been a focus of intense human activity and environmental impact since 1848 when gold was discovered in the foothills of California's Sierra Nevada mountains. As the estuary and its watershed continue to be changed by human activities, resource managers, environmental regulators, elected officials, and the public seek credible, unbiased scientific information about the factors related to observed changes in order to restore impaired species, habitats and ecological functions.
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The border region of the United States and Mexico encompasses a vast and diverse array of physical settings and habitats that include wetlands, deserts, rangeland, mountains, and forests, which are unique in terms of the diversity of their water, mineral, and biological resources. The region is interconnected economically, politically, and socially owing to its binational heritage. In 1995, nearly 11 million people lived immediately adjacent to the border. By one account, that population could more than double by 2020. This rapid population growth and consequent economic development and land-use changes are pushing the limits of environmental sustainability and quality. Infrastructure development has lagged behind the rapid growth of the region, resulting in a shortage of water for municipal, agricultural, and industrial uses. These stressors threaten the quality of life in the region and raise concerns about the interdependence of environmental quality and human health. To allow for continued economic growth while protecting the area’s natural resources and fostering a high quality of life, the United States and Mexico need an improved understanding of the threats posed by these anthropogenic changes. Issues of particular concern include (1) contaminants in ground water, surface water, and biota from agricultural, municipal, and industrial activities; (2) airborne pollutants from fossil-fuel combustion and other activities; (3) contaminants from past and present mining activities and mineral deposits; and (4) pathogens, pharmaceuticals, hormones, and other contaminants released in treated and untreated human and animal wastewaters.
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The Great Basin is an expanse of desert and high moun-tains situated between the Rocky Mountains and the Sierra Nevada of the western United States. The most explicit description of the Great Basin is that area in the West where surface waters drain inland. In other words, the Great Basin is comprised of many separate drainage areas - each with no outlet. What at first glance may appear as only a barren landscape, the Great Basin upon closer inspection reveals island mountains, sagebrush seas, and intermittent aquatic habitats, all teeming with an incredible number and variety of plants and animals. Biologists at the USGS are studying many different species and ecosystems in the Great Basin in order to provide information about this landscape for policy and land-management decision-making. The following stories represent a few of the many projects the USGS is conducting in the Great Basin.
Since the early 1990s, the magnitude and location of an earthquake have been available within minutes on the Internet. Now, as a result of work by the U.S. Geological Survey and with the cooperation of various regional seismic networks, people who experience an earthquake can go online and share information about its effects to help create a map of shaking intensities and damage. Such “Community Internet Intensity Maps” (CIIMs) contribute greatly toward the quick assessment of the scope of an earthquake emergency and provide valuable data for earthquake research.
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The U.S. Geological Survey (USGS) has advanced the use of moderate-resolution satellite data in a decision support system for assessing national fire potential. Weekly updated digital images of the Normalized Difference Vegetation Index (NDVI), based on data acquired at 1-kilometer (km) resolution (about 0.6 mi), have been used for the past 19 years as a means to assess live vegetation conditions for the purpose of rating fire danger. These images, produced and monitored through the growing season, portray the approximate time of greenup and senescence, as well as the relative amount and condition of growing plants.
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The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument aboard NASA?s Terra Earth Observing System (EOS) AM and Aqua EOS PM spacecrafts.
Section 2507 of Public Law 107-171 (2002 Farm Bill) provided $200,000,000 to be used by the Secretary of the Interior, acting through the Commissioner of Reclamation, to provide water to at-risk natural desert terminal lakes. This bill was later amended under Public Law 108-7, Section 207 to include language 'Restoration of fish, wildlife, and associated habitats in watersheds of certain lakes'. The amendment specified that only Pyramid, Summit, and Walker Lakes in the State of Nevada were to be considered under Section 2507, Public Law 107-171.
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