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At least 1,081 records · Page 60Linked to original sources
USGS2001

Clutch sizes and nests of tailed frogs from the Olympic Peninsula, Washington

In the summers 1995-1998, we sampled 168 streams (1,714 in of randomly selected 1-m bands) to determine distribution and abundance of stream amphibians in Olympic National Park, Washington. We found six nests (two in one stream) of the tailed frog, compared to only two nests with clutch sizes reported earlier for coastal regions. This represents only one nest per 286 in searched and one nest per 34 streams sampled. Tailed frogs occurred only in 94 (60%) of the streams and, for these waters, we found one nest per 171 in searched or one nest per 20 streams sampled. The numbers of eggs for four masses ((x) over bar = 48.3, range 40-55) were low but one single strand in a fifth nest had 96 eggs. One nest with 185 eggs likely represented communal egg deposition. Current evidence indicates a geographic trend with yearly clutches of relatively few eggs in coastal tailed frogs compared to biennial nesting with larger clutches for inland populations in the Rocky Mountains.

Northwest Science↗
USGS2026

Riverine pesticide trends in the United States: Assessing a decade of national-scale monitoring

Pesticides in freshwater systems can compromise water availability by degrading water quality, with implications for human health and aquatic life. Despite recognition of the need for national-scale monitoring and analysis, few studies have documented long-term trends in surface water pesticide contamination across the US. This study addresses that need by analyzing temporal trends and acute and chronic benchmark exceedances for aquatic life and human health from 81 river sites sampled from 2013 to 2022 using an analytical method targeting 80 pesticides. The majority (79%) of single site and pesticide combinations had too few pesticide detections to estimate trends. When detections were more frequent, increasing trends in concentration were twice as common as decreasing trends. Increasing pesticide concentrations were common in primary drainages of the Mississippi River Basin. Aquatic life benchmarks were exceeded by 19 pesticides, and exceedances were geographically widespread, with both acute and chronic aquatic life benchmark exceedances at 62% of sites. The herbicides atrazine and metolachlor and the insecticide imidacloprid were identified as the greatest threats to surface water availability based on their trends and aquatic life benchmark exceedances. These findings demonstrate the need for continued monitoring and trend analysis, driver investigation, and management strategies to protect freshwater resources.

conterminous United States↗
USGS2012

Ohio River backwater flood-inundation maps for the Saline and Wabash Rivers in southern Illinois

Digital flood-inundation maps for the Saline and Wabash Rivers referenced to elevations on the Ohio River in southern Illinois were created by the U.S. Geological Survey (USGS). The inundation maps, accessible through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights) at the USGS streamgage at Ohio River at Old Shawneetown, Illinois-Kentucky (station number 03381700). Current gage height and flow conditions at this USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?03381700. In addition, this streamgage is incorporated into the Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/) by the National Weather Service (NWS). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. That NWS forecasted peak-stage information, also shown on the Ohio River at Old Shawneetown inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, eight water-surface elevations were mapped at 5-foot (ft) intervals referenced to the streamgage datum ranging from just above the NWS Action Stage (31 ft) to above the maximum historical gage height (66 ft). The elevations of the water surfaces were compared to a Digital Elevation Model (DEM) by using a Geographic Information System (GIS) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage heights from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

Illinois;Kentucky↗
USGS2025

Two-stage models improve machine learning classifiers in wildlife research: A case study in identifying false positive detections of Ruffed Grouse

Autonomous recording units are increasingly being used to monitor wildlife on large geographic and temporal scales, paired with machine learning (ML) to automate detection of wildlife. However, false positive detections from ML classifiers can result in erroneous ecological models that can lead to misguided management and conservation actions. We used a two-stage general approach to understand and reduce false positive detections, a technique in which outputs of the primary classification model are passed to a secondary classification model to yield the probability that a detection from the primary model is a true positive detection. This approach is demonstrated on two open-source models that detect Ruffed Grouse ( Bonasa umbellus ). We analyzed over 9500 h of acoustic data collected in 2022–2023 from the Green Mountain National Forest in Vermont, USA, and found the two models detected different types of acoustic signals associated with differing life history traits. The first model yielded 4106 detections (71.5 % true positives) while the second model yielded 524 detections (17.0 % true positives). Secondary logistic regression models separated true positives and false positives with high accuracy (84.5 % and 89.8 % respectively). Our findings go beyond improving Ruffed Grouse monitoring and conservation efforts to, more broadly, illustrate how two-stage ML approaches can improve the use of model-derived detections in wildlife research.

Vermont↗
USGS1999

Improvements to the DRASTIC ground-water vulnerability mapping method

Ground-water vulnerability maps are designed to show areas of greatest potential for ground-water contamination on the basis of hydrogeologic and anthropogenic (human) factors. The maps are developed by using computer mapping hardware and software called a geographic information system (GIS) to combine data layers such as land use, soils, and depth to water. Usually, ground-water vulnerability is determined by assigning point ratings to the individual data layers and then adding the point ratings together when those layers are combined into a vulnerability map. Probably the most widely used ground-water vulnerability mapping method is DRASTIC, named for the seven factors considered in the method: Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone media, and hydraulic Conductivity of the aquifer (Aller and others, 1985, p. iv). The DRASTIC method has been used to develop ground-water vulnerability maps in many parts of the Nation; however, the effectiveness of the method has met with mixed success (Koterba and others, 1993, p. 513; U.S. Environmental Protection Agency, 1993; Barbash and Resek, 1996; Rupert, 1997). DRASTIC maps usually are not calibrated to measured contaminant concentrations. The DRASTIC ground-water vulnerability mapping method was improved by calibrating the point rating scheme to measured nitrite plus nitrate as nitrogen (NO2+NO3–N) concentrations in ground water on the basis of statistical correlations between NO2+NO3–N concentrations and land use, soils, and depth to water (Rupert, 1997). This report describes the calibration method developed by Rupert and summarizes the improvements in results of this method over those of the uncalibrated DRASTIC method applied by Rupert and others (1991) in the eastern Snake River Plain, Idaho.

Idaho;Nevada;Utah;Wyoming↗
USGS2002

Alien plant species threat assessment and management prioritization for Sequoia-Kings Canyon and Yosemite National Parks

Executive Summary This document reports the results of alien species surveys at Sequoia-Kings Canyon and Yosemite national parks. It includes the findings of a comprehensive literature review of the biology and ecology of all alien plant species found during these surveys and the ranking of those species for prioritizing management and control programs. Surveys primarily targeted areas of human disturbance, such as campgrounds, corrals, developments, roads, trails and pastures. Alien species richness was compared across elevational gradients within the parks. To compare and contrast species composition among sites, an exploratory cluster analysis of the sites included in the speciesrichness- by-elevation figures was conducted using ordination techniques. All alien species discovered during the directed surveys were grouped into one of four management priority categories based on their attributes, potential impacts, and geographical extent. Category 1 species are aliens that are currently restricted to a relatively small number of sites in each park and have either been shown to greatly affect native vegetation or have a high probability of causing serious impacts. Category 2 species are restricted to a relatively small number of sites and are ones that generally have a lesser effect on native vegetation. Category 3 species are broadly distributed in the parks, are apparently increasing their ranges within the parks, and are those that have been shown to have a great impact on native vegetation. Category 4 species are those that were detected by the surveys but not assigned to one of the three ranked categories and are considered low priority.

Open-File Report↗
USGS2012

Middle Rockies Ecoregion: Chapter 5 in Status and trends of land change in the Western United States--1973 to 2000

The Middle Rockies Ecoregion—characterized by steep, high-elevation mountain ranges and intermountain valleys—is a disjunct ecoregion composed of three distinct geographic areas: the Greater Yellowstone area in northwest Wyoming, southwest Montana, and eastern Idaho; the Bighorn Mountains in north-central Wyoming and south-central Montana; and the Black Hills in western South Dakota and eastern Wyoming (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion covers approximately 90,160 km2 (34,881 mi2), and its three distinct geographic sections are bordered by several other ecoregions (fig. 1). The Yellowstone section abuts the Montana Valley and Foothill Prairies and the Northern Rockies Ecoregions to the north, the Snake River Basin and the Central Basin and Range Ecoregions to the west, and the Wyoming Basin Ecoregion to the south and east. The Bighorn Mountains section lies between the Wyoming Basin Ecoregion to the west and the Northwestern Great Plains Ecoregion to the east, and it abuts the Montana Valleys and Foothill Prairies Ecoregion to the north. The Black Hills section is entirely surrounded by the Northwestern Great Plains Ecoregion. The Continental Divide crosses the ecoregion from the southeast along the Wind River Range, through Yellowstone National Park, and west along the Montana-Idaho border. On both sides of the divide, topographic relief causes local climate variability, particularly the effects of aspect, exposure to prevailing wind, thermal inversions, and rain-shadow effects, that are reflected in the wide variety of flora and fauna within the ecoregion (Ricketts and others, 1999).

Idaho;Montana;South Dakota;Wyoming↗
USGS2019

Impacts of Hurricane Irma on Florida Bay Islands, Everglades National Park, U.S.A.

Hurricane Irma made landfall in south Florida, USA, on September 10, 2017 as a category 4 storm. In January 2018, fieldwork was conducted on four previously (2014) sampled islands in Florida Bay, Everglades National Park to examine changes between 2014 and 2018. The objectives were to determine if the net impact of the storm was gain or loss of island landmass and/or elevation; observe and quantify impacts to mangroves; and identify distinctive sedimentary, biochemical, and/or geochemical signatures of the storm. Storm overwash deposits were measured in the field and, in general, interior island mudflats appeared to experience deposition ranging from ~ 0.5 to ~ 6.5 cm. Elevation changes were measured using real-time kinematic positioning and satellite receivers. Comparison of 2014 to 2018 elevation measurements indicates mangrove berms and transitional areas between mudflats and berms experienced erosion and loss of elevation, whereas interior mudflats gained elevation, possibly due to Hurricane Irma. Geographic information system analysis of pre- and post-storm satellite imagery indicates the western-most island, closest to the eye of the storm, lost 32 to 42% (~ 11 to 13 m) of the width of the eastern berm, and vegetated coverage was reduced 9.3% or ~ 9700 m 2 . Vegetated coverage on the eastern-most island was reduced by 1.9% or ~ 9200 m 2 . These results are compared to previous accounts of hurricane impacts and provide a baseline for examining long-term constructive and destructive aspects of hurricanes on the islands and the role of storms in resiliency of Florida Bay islands.

Florida↗
USGS2010

Georeferencing the Large-Scale Aerial Photographs of a Great Lakes Coastal Wetland: A Modified Photogrammetric Method

The geocontrol template method was developed to georeference multiple, overlapping analog aerial photographs without reliance upon conventionally obtained horizontal ground control. The method was tested as part of a long-term wetland habitat restoration project at a Lake Erie coastal wetland complex in the U.S. Fish and Wildlife Service Ottawa National Wildlife Refuge. As in most coastal wetlands, annually identifiable ground-control features required to georeference photo-interpreted data are difficult to find. The geocontrol template method relies on the following four components: (a) an uncontrolled aerial photo mosaic of the study area, (b) global positioning system (GPS) derived horizontal coordinates of each photo’s principal point, (c) a geocontrol template created by the transfer of fiducial markings and calculated principal points to clear acetate from individual photographs arranged in a mosaic, and (d) the root-mean-square-error testing of the system to ensure an acceptable level of planimetric accuracy. Once created for a study area, the geocontrol template can be registered in geographic information system (GIS) software to facilitate interpretation of multiple images without individual image registration. The geocontrol template enables precise georeferencing of single images within larger blocks of photographs using a repeatable and consistent method.

Ohio↗
USGS2009

Preliminary geologic map of the Laredo, Crystal City–Eagle Pass, San Antonio, and Del Rio 1° x 2° quadrangles, Texas, and the Nuevo Laredo, Ciudad Acuña, Piedras Negras, and Nueva Rosita 1° x 2° quadrangles, Mexico

The purpose of this map is to provide an integrated, bi-national geologic map dataset for display and analyses on an Arc Internet Map Service (IMS) dedicated to environmental health studies in the United States-Mexico border region. The IMS web site was designed by the US-Mexico Border Environmental Health Initiative project and collaborators, and the IMS and project web site address is http://borderhealth.cr.usgs.gov/. The objective of the project is to acquire, evaluate, analyze, and provide earth, biologic, and human health resources data within a GIS framework (IMS) to further our understanding of possible linkages between the physical environment and public health issues. The geologic map dataset is just one of many datasets included in the web site; other datasets include biologic, hydrologic, geographic, and human health themes.

Laredo, Crystal City–Eagle Pass, San Antonio, and ↗
USGS2017

Flood-inundation maps for the Big Blue River at Shelbyville, Indiana

Digital flood-inundation maps for a 4.1-mile reach of the Big Blue River at Shelbyville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The floodinundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at https://water. usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Big Blue River at Shelbyville, Ind. (station number 03361500). Near-real-time stages at this streamgage may be obtained from the USGS National Water Information System at https://waterdata. usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at https://water.weather.gov/ ahps/, which also forecasts flood hydrographs at this site (SBVI3). Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relation at the Big Blue River at Shelbyville, Ind., streamgage. The calibrated hydraulic model was then used to compute 12 water-surface profiles for flood stages referenced to the streamgage datum and ranging from 9.0 feet, or near bankfull, to 19.4 feet, the highest stage of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a Geographic Information System digital elevation model (derived from light detection and ranging [lidar] data having a 0.98-foot vertical accuracy and 4.9-foot horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage at the Big Blue River at Shelbyville, Ind., and forecasted stream stages from the NWS, will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post-flood recovery efforts.

Indiana↗
USGS1989

Review of edgematchimg procedures for digital cartographic data used in Geographic Information Systems (GIS)

In the process of developing a continuous hydrographic data layer for water resources applications in the Pacific Northwest, map-edge discontinuities in the U.S. Geological Survey 1:100 ,000-scale digital data that required application of computer-assisted edgematching procedures were identified. The spatial data sets required by the project must have line features that match closely enough across map boundaries to ensure full line topology when adjacent files are joined by the computer. Automated edgematching techniques are evaluated as to their effects on positional accuracy. Interactive methods such as selective node-matching and on-screen editing are also reviewed. Interactive procedures complement automated methods by allowing supervision of edgematching in a cartographic and hydrologic context. Common edge conditions encountered in the preparation of the Northwest Rivers data base are described, as are recommended processing solutions. Suggested edgematching procedures for 1:100,000-scale hydrography data are included in an appendix to encourage consistent processing of this theme on a national scale. (USGS)

Open-File Report↗
USGS2017

The role of the North American Breeding Bird Survey in conservation

The North American Breeding Bird Survey (BBS) was established in 1966 in response to a lack of quantitative data on changes in the populations of many bird species at a continental scale, especially songbirds. The BBS now provides the most reliable regional and continental trends and annual indices of abundance available for >500 bird species. This paper reviews some of the ways in which BBS data have contributed to bird conservation in North America over the past 50 yr, and highlights future program enhancement opportunities. BBS data have contributed to the listing of species under the Canadian Species at Risk Act and, in a few cases, have informed species assessments under the U.S. Endangered Species Act. By raising awareness of population changes, the BBS has helped to motivate bird conservation efforts through the creation of Partners in Flight. BBS data have been used to determine priority species and locations for conservation action at regional and national scales through Bird Conservation Region strategies and Joint Ventures. Data from the BBS have provided the quantitative foundation for North American State of the Birds reports, and have informed the public with regard to environmental health through multiple indicators, such as the Canadian Environmental Sustainability Indicators and the U.S. Environmental Protection Agency's Report on the Environment. BBS data have been analyzed with other data (e.g., environmental, land cover, and demographic) to evaluate potential drivers of population change, which have then informed conservation actions. In a few cases, BBS data have contributed to the evaluation of management actions, including informing the management of Mourning Doves ( Zenaida macroura ), Wood Ducks ( Aix sponsa ), and Golden Eagles ( Aquila chrysaetos ). Improving geographic coverage in northern Canada and in Mexico, improving the analytical approaches required to integrate data from other sources and to address variation in detectability, and completing the database, by adding historical bird data at each point count location and pinpointing the current point count locations would further enhance the survey's value.

Condor↗
USGS2013

Tectonic map of the Circum-Pacific region, Pacific basin sheet

Circum-Pacific Map Project : The Circum-Pacific Map Project was a cooperative international effort designed to show the relationship of known energy and mineral resources to the major geologic features of the Pacific basin and surrounding continental areas. Available geologic, mineral, and energy-resource data are being complemented by new, project-developed data sets such as magnetic lineations, seafloor mineral deposits, and seafloor sediment. Earth scientists representing some 180 organizations from more than 40 Pacific-region countries are involved in this work. Six overlapping equal-area regional maps at a scale of 1:10,000,000 form the cartographic base for the project: the four Circum-Pacific Quadrants (Northwest, Southwest, Southeast, and Northeast), and the Antarctic and Arctic Sheets. There is also a Pacific Basin Sheet at a scale of 1:17,000,000. The Base Map Series and the Geographic Series (published from 1977 to 1990), the Plate-Tectonic Series (published in 1981 and 1982), the Geodynamic Series (published in 1984 and 1985), and the Geologic Series (published from 1984 to 1989) all include six map sheets. Other thematic map series in preparation include Mineral-Resources, Energy-Resources and Tectonic Maps. Altogether, more than 50 map sheets are planned. The maps were prepared cooperatively by the Circum-Pacific Council for Energy and Mineral Resources and the U.S. Geological Survey and are available from the Branch of Distribution, U. S. Geological Survey, Box 25286, Federal Center, Denver, Colorado 80225, U.S.A. The Circum-Pacific Map Project is organized under six panels of geoscientists representing national earth-science organizations, universities, and natural-resource companies. The six panels correspond to the basic map areas. Current panel chairmen are Tomoyuki Moritani (Northwest Quadrant), R. Wally Johnson (Southwest Quadrant), Ian W.D. Dalziel (Antarctic Region), vacant. (Southeast Quadrant), Kenneth J. Drummond (Northeast Quadrant), and George W. Moore (Arctic Region). Project coordination and final cartography was being carried out through the cooperation of the Office of the Chief Geologist of the U.S. Geological Survey, under the direction of General Chairman, George Gryc of Menlo Park, California. Project headquarters were located at 345 Middlefield Road, MS 952, Menlo Park, California 94025, U.S.A. The framework for the Circum-Pacific Map Project was developed in 1973 by a specially convened group of 12 North American geoscientists meeting in California. The project was officially launched at the First Circum-Pacific Conference on Energy and Mineral Resources, which met in Honolulu, Hawaii, in August 1974. Sponsors of the conference were the AAPG, Pacific Science Association (PSA), and the Coordinating Committee for Offshore Prospecting for Mineral Resources in Offshore Asian Areas (CCOP). The Circum-Pacific Map Project operates as an activity of the Circum-Pacific Council for Energy and Mineral Resources, a nonprofit organization that promotes cooperation among Circum-Pacific countries in the study of energy and mineral resources of the Pacific basin. Founded by Michel T. Halbouty in 1972, the Council also sponsors conferences, topical symposia, workshops and the Earth Science Series books. Tectonic Map Series : The tectonic maps distinguish areas of oceanic and continental crust. Symbols in red mark active plate boundaries, and colored patterns show tectonic units (volcanic or magmatic arcs, arc-trench gaps, and interarc basins) associated with active plate margins. Well-documented inactive plate boundaries are shown by symbols in black. The tectonic development of oceanic crust is shown by episodes of seafloor spreading. These correlate with the rift and drift sequences at passive continental margins and episodes of tectonic activity at active plate margins. The recognized episodes of seafloor spreading seem to reflect major changes in plate kinematics. Oceanic plateaus and other prominences of greater than normal oceanic crustal thickness such as hotspot traces are also shown. Colored areas on the continents show the ages of deformation and metamorphism of basement rocks and the emplacement of igneous rocks. Transitional tectonic (molassic) and reactivation basins are shown by a colored boundary, and if they are deformed, a colored horizontal line pattern indicates the age of deformation. Colored bands along basin boundaries indicate age of inception, and isopachs indicate thickness of platform strata on continental crust and cover on oceanic crust. Colored patterns at separated continental margins show the age of inception of rift and drift (breakup) sequences. Symbols mark folds and faults, and special symbols show volcanoes and other structural features. Affiliations are as of compilation of the data. This map was created in quadrants and then compiled together. They are the Northwest land, Northwest Marine (different compilers), Northeast, Southwest and Southeast, and parts in plate-boundary sections.

Circum-Pacific Map↗
USGS2007

Map and data for Quaternary faults and fault systems on the Island of Hawai'i

Introduction This report and digitally prepared, GIS-based map is one of a series of similar products covering individual states or regions of United States that show the locations, ages, and activity rates of major earthquake-related features such as faults and fault-related folds. It is part of a continuing the effort to compile a comprehensive Quaternary fault and fold map and database for the United States, which is supported by the U.S. Geological Survey's (USGS) Earthquake Hazards Program. Guidelines for the compilation of the Quaternary fault and fold maps for the United States were published by Haller and others (1993) at the onset of this project. This compilation of Quaternary surface faulting and folding in Hawai`i is one of several similar state and regional compilations that were planned for the United States. Reports published to date include West Texas (Collins and others, 1996), New Mexico (Machette and others, 1998), Arizona (Pearthree, 1998), Colorado (Widmann and others, 1998), Montana (Stickney and others, 2000), Idaho (Haller and others, 2005), and Washington (Lidke and others, 2003). Reports for other states such as California and Alaska are still in preparation. The primary intention of this compilation is to aid in seismic-hazard evaluations. The report contains detailed information on the location and style of faulting, the time of most recent movement, and assigns each feature to a slip-rate category (as a proxy for fault activity). It also contains the name and affiliation of the compiler, date of compilation, geographic and other paleoseismologic parameters, as well as an extensive set of references for each feature. The map (plate 1) shows faults, volcanic rift zones, and lineaments that show evidence of Quaternary surface movement related to faulting, including data on the time of most recent movement, sense of movement, slip rate, and continuity of surface expression. This compilation is presented as a digitally prepared map product and catalog of data, both in Adobe Acrobat PDF format. The senior authors (Eric C. Cannon and Roland Burgmann) compiled the fault data as part of ongoing studies of active faulting on the Island of Hawai`i. The USGS is responsible for organizing and integrating the State or regional products under their National Seismic Hazard Mapping project, including the coordination and oversight of contributions from individuals and groups (Michael N. Machette and Anthony J. Crone), database design and management (Kathleen M. Haller), and digitization and analysis of map data (Richard L. Dart). After being released an Open-File Report, the data in this report will be available online at http://earthquake.usgs.gov/regional/qfaults/, the USGS Quaternary Fault and Fold Database of the United States.

Hawaii↗
USGS2015

Final project memorandum: sea-level rise modeling handbook: resource guide for resource managers, engineers, and scientists

Coastal wetlands of the Southeastern United States are undergoing retreat and migration from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. Much of the literature describing potential sea-level rise projections and modeling predictions are found in peer-reviewed academic journals or government technical reports largely suited to reading by other Ph.D. scientists who are more familiar or engaged in the climate change debate. Various sea-level rise and coastal wetland models have been developed and applied of different designs and scales of spatial and temporal complexity for predicting habitat and environmental change that have not heretofore been synthesized to aid natural resource managers of their utility and limitations. Training sessions were conducted with Federal land managers with U.S. Fish and Wildlife Service, National Park Service, and NOAA National Estuarine Research Reserves as well as state partners and nongovernmental organizations across the northern Gulf Coast from Florida to Texas to educate and to evaluate user needs and understanding of concepts, data, and modeling tools for projecting sea-level rise and its impact on coastal habitats and wildlife. As a result, this handbook was constructed from these training and feedback sessions with coastal managers and biologists of published decision-support tools and simulation models for sea-level rise and climate change assessments. A simplified tabular context was developed listing the various kinds of decision-support tools and ecological models along with criteria to distinguish the source, scale, and quality of information input and geographic data sets, physical and biological constraints and relationships, datum characteristics of water and land elevation components, utility options for setting sea-level rise and climate change scenarios, and ease or difficulty of storing, displaying, or interpreting model output. The handbook is designed to be a primer to understanding sea-level rise and a practical synthesis of the current state of knowledge and modeling tools as a resource guide for DOl land management needs and facilitating Landscape Conservation Cooperative (LCC) research and conservation initiatives.

Conference Paper↗
USGS1960

National water resources and problems

Water problems exist in all parts of the United States. Furthermore, the problems are becoming more acute and widespread as population and industry grow. The need is pressing for wider appreciation of the nature of water problems. This requires a background of basic facts about the occurrence of water, its quantity and quality, and the manner in which it is used. This report records some of these basic facts. The facts are that the United States as a whole is well endowed with water. Many water problems (which exist in our country) are caused, however,by poor distribution of water in time and place. Because the nationwide supply of water is large, any given locality could be supplied with water sufficient in quantity and suitable in quality, provided that those who need the water can pay the cost. For the most part, then, water problems are basically social and economic. While management is needed, both locally and regionally, with flexibility to respond to broad geographic patterns of economic and social development.

Report↗
USGS1993

Digital Elevation Models

The Earth Science Information Center (ESIC) distributes digital cartographic/geographic data files produced by the U.S. Geological Survey (USGS) as part of the National Mapping Program. Digital cartographic data files may be grouped into four basic types. The first of these, called a Digital Line Graph (DLG), is the line map information in digital form. These data files include information on base data categories, such as transportation, hypsography, hydrography, and boundaries. The second type, called a Digital Elevation Model (DEM), consists of a sampled array of elevations for a number of ground positions at regularly spaced intervals. The third type is Land Use and Land Cover digital data which provides information on nine major classes of land use such as urban, agricultural, or forest as well as associated map data such as political units and Federal land ownership. The fourth type, the Geographic Names Information System, provides primary information for all known places, features, and areas in the United States identified by a proper name.

Data Users Guide↗