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At least 19 recordsLinked to original sources
USGS1998

Contaminant Hazard Reviews. [Reports No. 1-28 on CD-ROM.]

This compact disc (CD) contains the first 28 reports in the Contaminant Hazard Reviews (CHR) that were published originally between 1985 and 1994 in the U.S. Department of the Interior Biological Report series. The CD was produced because printed supplies of these reviews--a total of 84,000--became exhausted and demand remained high. Each review was prepared at the request of environmental specialists of the U.S. Fish and Wildlife Service and each contained specific information on mirex, cadmium, carbofuran, toxaphene, selenium, chromium, polychlorinated biphenyls, dioxins, diazinon, mercury, polycyclic aromatic hydrocarbons, arsenic, chlorpyrifos, lead, tin, index issue, pentachlorophenol, atrazine, molybdenum, boron, chlordane, paraquat, cyanide, fenvalerate, diflubenzuron, zinc, famphur, or acrolein. Each report reviewed and synthesized the technical literature on a single contaminant and its effects on terrestrial plants and invertebrates, aquatic plants and animals, avian and mammalian wildlife, and other natural resources. The subtopics include contaminant sources and uses; physical, chemical, and metabolic properties; concentrations in field collections of abiotic materials and living organisms; deficiency effects, where appropriate; lethal and sublethal effects, including effects on survival, growth, reproduction, metabolism, mutagenicity, teratogenicity, and carcinogenicity; proposed criteria for the protection of human health and sensitive natural resources; and recommendations for additional research.

Book↗
USGS2006

Endocrine disrupting chemicals research program of the U.S. Environmental Protection Agency: summary of a peer-review report

At the request of the U.S. Environmental Protection Agency (EPA) Office of Research and Development, a subcommittee of the Board of Scientific Counselors Executive Committee conducted an independent and open peer review of the Endocrine Disrupting Chemicals Research Program (EDC Research Program) of the U.S. EPA. The subcommittee was charged with reviewing the design, relevance, progress, scientific leadership, and resources of the program. The subcommittee found that the long-term goals and science questions in the EDC Program are appropriate and represent an understandable and solid framework for setting research priorities, representing a combination of problem-driven and core research. Long-term goal (LTG) 1, dealing with the underlying science surrounding endocrine disruptors, provides a solid scientific foundation for conducting risk assessments and making risk management decisions. LTG 2, dealing with defining the extent of the impact of endocrine-disrupting chemicals (EDCs), has shown greater progress on ecologic effects of EDCs compared with that on human health effects. LTG 3, which involves support of the Endocrine Disruptor Screening and Testing Program of the U.S. EPA, has two mammalian tests already through a validation program and soon available for use. Despite good progress, we recommend that the U.S. EPA a ) strengthen their expertise in wildlife toxicology, b ) expedite validation of the Endocrine Disruptors Screening and Testing Advisory Committee tests, c ) continue dependable funding for the EDC Research Program, d ) take a leadership role in the application of “omics” technologies to address many of the science questions critical for evaluating environmental and human health effects of EDCs, and e ) continue to sponsor multidisciplinary intramural research and interagency collaborations.

Environmental Health Perspectives↗
USGS2014

Environmental DNA calibration study. Interim technical review report

Invasive aquatic nuisance species pose a major threat to aquatic ecosystems worldwide. Invasive Asian carps, including bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) have been steadily dispersing upstream through the Mississippi, Illinois, and Des Plaines Rivers since the 1990s. To prevent further movement up the Illinois River into the Chicago Area Waterway System (CAWS, see Figures 1.1.1 to 1.1.3) and possibly Lake Michigan and the Great Lakes ecosystem, an electrical barrier has been operating near Lockport to deter the advance of Asian carp. Although one adult individual has been detected in Lockport pool of the Illinois Waterway, the leading edge of the invasion of bighead and silver carp is considered to be at RM 281.5 in Dresden Island Pool, 15 miles downstream from the barrier and 55 miles from Lake Michigan, and that front has not progressed upstream since 2006. Although spawning activity has been observed in Marseilles pool in 2012, verified capture of eggs and larvae remain downstream in Peoria pool, over 140 miles from Lake Michigan (Figure 1.1.1). Should a sustainable Asian carp population become established in the Great Lakes, native fish populations, as well as many threatened or endangered plant/animal species populations, could be impacted. In response to this threat, the Asian Carp Regional Control Committee (ACRCC) was formed in part to coordinate efforts to understand and organize against the Asian carp threat. The Asian Carp Control Strategy Framework (2012a) outlined major tasks to be completed for a better understanding of factors related to the advance of Asian carp populations towards the Great Lakes. In addition, the ACRCC formed the Monitoring and Rapid Response Workgroup to address Asian carp monitoring and removal (ACRCC 2012b).

Midwest waterways↗
USGS2015

Environmental DNA calibration study interim technical review report December 2014

The Environmental DNA Calibration Study (ECALS) is a multi-year study to improve the understanding and interpretation of the detection of Asian carp DNA in environmental samples (eDNA) used in early detection monitoring. eDNA surveillance programs seek to detect the presence of genetic material (DNA in cells sloughed off in slime, feces, urine, etc.) extracted from water samples; the detection of genetic material is linked to the possible presence of Asian carp. The study involves collaboration between the U.S. Army Corps of Engineers, the U.S. Geological Survey, and the U.S. Fish and Wildlife Service. ECALS addresses three major Action Items from the Asian Carp Regional Coordinating Committee (ACRCC) Asian Carp Control Strategy Framework, of which results to date are presented below. Initial ECALS efforts focused on eDNA vectors whereas marker development and calibration experiments received greater attention in 2013.

Report↗
USGS1983

Petroleum and mineral resources of Antarctica

No known petroleum or mineral resources occur in Antarctica. The data on these subjects have been collected, mainly since the IGY (International Geophysical Year), 1957-58, as a part of other research carried out by geologists and geophysicists from a number of countries. Specific resource-related studies have not been made. Wright and Williams (1974) summarized what was known of Antarctic mineral resources a decade ago. The U.S. Geological Survey has been actively pursuing various investigations in Antarctica since 194 7. In the course of this work and that of our colleagues elsewhere in the United States and in other countries, much information relevant to petroleum and mineral resources has been obtained. Since 1976, modern state-of-the-art multichannel seismic reflection and aeromagnetic surveys by several countries over the continental margin of Antarctica have indicated thick sedimentary basins. However, no offshore drilling beneath the continental shelf has taken place since the DSDP (Deep Sea Drilling Project) holes in the Ross Sea in 1973. Geologic field investigations begun at the turn of the twentieth century have been intensified in the past two decades; most rock outcrops have been visited and samples collected. Technology to exploit resources, particularly in the Arctic, has been developing at a rapid rate, and much of it could be applied to Antarctica. As a result of the petroleum price increases of the past decade, the attention of a number of countries has turned to Antarctica, but under the policy of "voluntary restraint" adopted by the Antarctic Treaty nations, no active petroleum or mineral exploration is taking place. The Antarctic treaty countries are in the process of negotiating an Antarctic mineral resources regime that is anticipated to be completed within the next several years. Therefore it seemed timely to us to readdress the question of petroleum and mineral resources. These reports review and summarize the available information. The first report summarizes the information relevant to petroleum resources. Although uneconomic at present, petroleum is generally considered more likely to be exploited (if supergiant fields were ever found) in the next few decades than hard minerals. The second report reviews the reported occurrences of minerals in Antarctica and discusses their significance. The final report discusses the Dufek layered mafic intrusion, second only to the Bushveld Complex in size in the world; the Dufek intrusion might be considered as a potential target for mineral exploration.

Circular↗
USGS2012

Deep-Sea Turbidites as Guides to Holocene Earthquake History at the Cascadia Subduction Zone—Alternative Views for a Seismic-Hazard Workshop

This report reviews the geological basis for some recent estimates of earthquake hazards in the Cascadia region between southern British Columbia and northern California. The largest earthquakes to which the region is prone are in the range of magnitude 8-9. The source of these great earthquakes is the fault down which the oceanic Juan de Fuca Plate is being subducted or thrust beneath the North American Plate. Geologic evidence for their occurrence includes sedimentary deposits that have been observed in cores from deep-sea channels and fans. Earthquakes can initiate subaqueous slumps or slides that generate turbidity currents and which produce the sedimentary deposits known as turbidites. The hazard estimates reviewed in this report are derived mainly from deep-sea turbidites that have been interpreted as proxy records of great Cascadia earthquakes. The estimates were first published in 2008. Most of the evidence for them is contained in a monograph now in press. We have reviewed a small part of this evidence, chiefly from Cascadia Channel and its tributaries, all of which head offshore the Pacific coast of Washington State. According to the recent estimates, the Cascadia plate boundary ruptured along its full length in 19 or 20 earthquakes of magnitude 9 in the past 10,000 years; its northern third broke during these giant earthquakes only, and southern segments produced at least 20 additional, lesser earthquakes of Holocene age. The turbidite case for full-length ruptures depends on stratigraphic evidence for simultaneous shaking at the heads of multiple submarine canyons. The simultaneity has been inferred primarily from turbidite counts above a stratigraphic datum, sandy beds likened to strong-motion records, and radiocarbon ages adjusted for turbidity-current erosion. In alternatives proposed here, this turbidite evidence for simultaneous shaking is less sensitive to earthquake size and frequency than previously thought. Turbidites far below a channel confluence, instead of representing the merged flows from two tributaries, monitor the dominant tributary only. Sandy beds low in the turbidites, instead of matching from channel to channel, permit divergent stratigraphic correlations; and rather than approximating strong-motion seismograms, the sandy beds more likely record processes internal to the generation and transformation of subaqueous mass movements. The age adjustments, instead of supporting other evidence that all the northern ruptures were long, are uncertain enough to accord with variation in rupture mode, and this variation improves agreement with onshore paleoseismology. Many of the turbidites counted as evidence for frequent earthquakes on the southern Cascadia plate boundary may instead reflect nearness to steep slopes. This report is meant to aid in the updating of national maps of seismic hazards in Canada and the United States. It offers three main conclusions for consideration at a U.S. hazard-map workshop slated for March 21-22, 2012: If giant earthquakes are the norm for the plate boundary offshore southern Washington, the strongest paleoseismic evidence for this rupture mode is the average earthquake-recurrence interval of about 500 years that is evidenced both offshore in lower Cascadia Channel and onshore at estuaries of southern Washington and northernmost Oregon. The plate boundary offshore southern British Columbia and northern Washington may be capable of producing great earthquakes at an average interval as short as 300 years that is evidenced mainly onshore. Review of more of the turbidite evidence now in press may clarify implications for the hazard maps. Further work on the deep-sea turbidites could target sedimentary processes and chronological uncertainties that may affect the turbidites' sensitivity to fault-rupture lengths and recurrence rates.

Washington;Oregon;California↗
USGS1987

Manmade organic compounds in the surface waters of the United States: a review of current understanding

This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves between water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be absorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rate commonly follow a first-order kinetic process. Eight groups of manmade organic compounds are discussed: 1. Polychlorinated biphenyls and organochlorine insecticides, 2. Carbamate and organophosphorus insecticides, 3. Herbicides, 4. Phenols, 5. Halogenated aliphatic and monocyclic aromatic hydrocarbons, 6. Phthalate esters, 7. Polychlorinated dibenzo-p-dioxins, and 8. Polycyclic aromatic hydrocarbons. For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence that the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison to concentrations determined during ongoing research. Finally, where sufficient data exist, regional and temporal contamination trends in the United States are discussed.

Open-File Report↗
USGS2008

Abundance Trends and Status of the Little Colorado River Population of Humpback Chub: An Update Considering 1989-2006 Data

EXECUTIVE SUMMARY In 1967, the humpback chub (Gila cypha) (HBC) was added to the federal list of endangered species and is today protected under the Endangered Species Act of 1973. Only six populations of humpback chub are currently known to exist, five in the Colorado River Basin above Lees Ferry, Arizona, and one in Grand Canyon, Arizona. The majority of Grand Canyon humpback chub are found in the Little Colorado River (LCR)-the largest tributary to the Colorado River in Grand Canyon-and the Colorado River near its confluence with the Little Colorado River. Monitoring and research of the Grand Canyon humpback chub population is overseen by the U.S. Geological Survey's (USGS) Grand Canyon Monitoring and Research Center (GCMRC) under the auspices of the Glen Canyon Dam Adaptive Management Program (GCDAMP), a Federal initiative to protect and improve resources downstream of Glen Canyon Dam. This report provides updated information on the status and trends of the LCR population in light of new information and refined assessment methodology. An earlier assessment of the LCR population (Coggins and others, 2006a) used data collected during 1989?2002; the assessment provided here includes that data and additional data collected through 2006. Catch-rate indices, closed population mark-recapture model abundance estimates, results from the original age-structured mark recapture (ASMR) model (Coggins and others, 2006b), and a newly refined ASMR model are presented. This report also seeks to (1) formally evaluate alternative stock assessment models using Pearson residual analyses and information theoretic procedures, (2) use mark-recapture data to estimate the relationship between HBC age and length, (3) translate uncertainty in the assignment of individual fish age to resulting estimates of recruitment and abundance from the ASMR model, and (4) evaluate past and present stock assessments considering the available data sources and analyses, recognizing the limitations inherent in both. A major task of this study was to improve the overall methodology used to conduct HBC stock assessment by addressing concerns identified in an independent review conducted in 2003 (Kitchell and others, 2003). The review report identified that the current technique of assigning age to individual fish based on length was a potential source of bias in ASMR estimates of abundance and recruitment, and called for a more complete examination of this potential error source. Additionally, the review suggested that further work to develop procedures to better arbitrate among alternative assessment models (e.g., ASMR 1?3) would be beneficial. To address the first of the concerns identified by the independent review, this study uses mark-recapture data to develop a temperature-dependent growth model to characterize the relationship between HBC age and length. This model attempts to account for temperature differences resulting from both ontogenetic habitat shifts between the Little Colorado and the mainstem Colorado Rivers as well as seasonal variation in water temperature within the LCR. The resulting growth model is then used to characterize the error in assigning age to individual fish based on length. Results presented in this study suggest that ageing error does not result in large bias in either abundance or recruitment estimates from the ASMR model. However, incorporating ageing error into the assessment does result in less precise estimates, particularly for recruitment. To address the second concern brought forward in the review report related to model selection procedures, this study arbitrated among the competing models by both examining model fit using Pearson residual analyses and considering information theoretic measures. Although adult abundance estimates and trend varied little among all models considered, these procedures identified ASMR 3 as the model whose underlying assumptions were most consistent with the data. Because ASMR 3 is

Open-File Report↗
USGS2018

U.S. Department of the Interior Climate Science Centers and U.S. Geological Survey National Climate Change and Wildlife Science Center—Annual report for 2017

Introduction The year 2017 was a year of review and renewal for the Department of the Interior (DOI) Climate Science Centers (CSCs) and the U.S. Geological Survey (USGS) National Climate Change and Wildlife Science Center (NCCWSC). The Southeast, Northwest, Alaska, Southwest, and North Central CSCs’ 5-year summary review reports were released in 2017 and contain the findings of the external review teams led by the Cornell University Human Dimensions Research Unit in conjunction with the American Fisheries Society. The reports for the Pacific Islands, South Central, and Northeast CSCs are planned for release in 2018. The reviews provide an opportunity to evaluate aspects of the cooperative agreement, such as the effectiveness of the CSC in meeting project goals and assessment of the level of scientific contribution and achievement. These reviews serve as a way for the CSCs and NCCWSC to look for ways to recognize and enhance our network’s strengths and identify areas for improvement. The reviews were followed by the CSC recompetition, which led to new hosting agreements at the Northwest, Alaska, and Southeast CSCs. Learn more about the excellent science and activities conducted by the network centers in the 2017 annual report.

Open-File Report↗
USGS2015

Literature review of giant gartersnake ( Thamnophis gigas ) biology and conservation

This report reviews the available literature on giant gartersnakes ( Thamnophis gigas ) to compile existing information on this species and identify knowledge gaps that, if addressed, would help to inform conservation efforts for giant gartersnakes. Giant gartersnakes comprise a species of semi-aquatic snake precinctive to wetlands in the Central Valley of California. The diversion of surface water and conversion of wetlands to agricultural and other land uses resulted in the loss of more than 90 percent of natural giant gartersnake habitats. Because of this habitat loss, giant gartersnakes are now listed by the United States and California Endangered Species Acts as Threatened. Most extant populations occur in the rice-growing regions of the Sacramento Valley, which comprises the northern portion of the giant gartersnake’s former range. The huge demand for water in California for agriculture, industry, recreation, and other human consumption, combined with periodic severe drought, places remaining giant gartersnake habitats at increased risk of degradation and loss. This literature review summarizes the available information on giant gartersnake distribution, habitat relations, behavior, demography, and other aspects of its biology relevant to conservation. This information is then compiled into a graphical conceptual model that indicates the importance of different aspects of giant gartersnake biology for maintaining positive population growth, and identifies those areas for which important information relevant for conservation is lacking. Directing research efforts toward these aspects of giant gartersnake ecology will likely result in improvements to conserving this unique species while meeting the high demands for water in California.

Open-File Report↗
USGS2013

Review of selected global mineral industries in 2011 and an outlook to 2017

This report reviews the world production of selected mineral commodities in 2011 and includes output projections (based on planned capacity expansions) through 2017. It also includes brief discussions of several issues that are of importance to the mineral sector, including the world economy, the availability of strategic minerals, significant company mergers and acquisitions in 2011, exploration investment made during the year, and the moves towards resource nationalization and expropriation of mineral assets by national Governments.

Open-File Report↗
USGS2013

Integrating Federal and State data records to report progress in establishing agricultural conservation practices on Chesapeake Bay farms

In response to the Executive Order for Chesapeake Bay Protection and Restoration (E.O. #13508, May 12, 2009), the U.S. Geological Survey (USGS) took on the task of acquiring and assessing agricultural conservation practice data records for U.S. Department of Agriculture (USDA) programs, and transferred those datasets in aggregated format to State jurisdictional agencies for use in reporting conservation progress to the Chesapeake Bay Program Partnership (CBP Partnership). Under the guidelines and regulations that have been developed to protect and restore water-quality in the Chesapeake Bay, the six State jurisdictions that fall within the Chesapeake Bay watershed are required to report their progress in promoting agricultural conservation practices to the CBP Partnership on an annual basis. The installation and adoption of agricultural best management practices is supported by technical and financial assistance from both Federal and State conservation programs. The farm enrollment data for USDA conservation programs are confidential, but agencies can obtain access to the privacy-protected data if they are established as USDA Conservation Cooperators. The datasets can also be released to the public if they are first aggregated to protect farmer privacy. In 2012, the USGS used its Conservation Cooperator status to obtain implementation data for conservation programs sponsored by the USDA Natural Resources Conservation Service (NRCS) and the USDA Farm Service Agency (FSA) for farms within the Chesapeake Bay watershed. Three jurisdictions (Delaware, Pennsylvania, and West Virginia) used the USGS-provided aggregated dataset to report conservation progress in 2012, whereas the remaining three jurisdictions (Maryland, New York, and Virginia) used jurisdictional Conservation Cooperator Agreements to obtain privacy-protected data directly from the USDA. This report reviews the status of conservation data sharing between the USDA and the various jurisdictions, discusses the methods that were used by the USGS in 2012 to collect and process USDA agricultural conservation data, and also documents methods that were used by the jurisdictions to integrate Federal and State data records, reduce double counting, and provide an accurate reporting of conservation practices to the CBP Partnership’s Annual Progress Review. A similar tracking, reporting, and assessment will occur in future years, as State and Federal governments and nongovernmental organizations continue to work with farmers and conservation districts to reduce the impacts of agriculture on water-quality.

Delaware; Maryland; New York; Pennsylvania;Virgini↗
USGS2018

Data analysis considerations for pesticides determined by National Water Quality Laboratory schedule 2437

In 2013, the U.S. Geological Survey National Water Quality Laboratory (NWQL) made a new method available for the analysis of pesticides in filtered water samples: laboratory schedule 2437. Schedule 2437 is an improvement on previous analytical methods because it determines the concentrations of 225 fungicides, herbicides, insecticides, and associated degradates in one method at similar or lower concentrations than previously available methods. Additionally, the pesticides included in schedule 2437 were strategically identified in a prioritization analysis that assessed likelihood of occurrence, prevalence of use, and potential toxicity. When the NWQL reports pesticide concentrations for analytes in schedule 2437, the laboratory also provides supplemental information useful to data users for assessing method performance and understanding data quality. That supplemental information is discussed in this report, along with an initial analysis of analytical recovery of pesticides in water-quality samples analyzed by schedule 2437 during 2013–2015. A total of 523 field matrix spike samples and their paired environmental samples and 277 laboratory reagent spike samples were analyzed for this report (1,323 samples total). These samples were collected in the field as part of the U.S. Geological Survey National Water-Quality Assessment groundwater and surface-water studies and as part of the NWQL quality-control program. This report reviews how pesticide samples are processed by the NWQL, addresses how to obtain all the data necessary to interpret pesticide concentrations, explains the circumstances that result in a reporting level change or the occurrence of a raised reporting level, and describes the calculation and assessment of recovery. This report also discusses reasons why a data user might choose to exclude data in an interpretive analysis and outlines the approach used to identify the potential for decreased data quality in the assessment of method recovery. The information provided in this report is essential to understanding pesticide data determined by schedule 2437 and should be reviewed before interpretation of these data.

Scientific Investigations Report↗
USGS1977

Review and analysis of hydrogeologic conditions near the site of a potential nuclear-waste repository, Eddy and Lea counties, New Mexico

This interim report reviews and summarizes the hydrogeology of rocks associated with the Permian salt beds (Castile and Salado Formations) of Los Medanos area in southeastern New Mexico. The information will be considered, together with other factors, in the preparation of an analysis of the impact of a potential nuclear-waste repository on the environment. Most of the geologic units in and adjacent to the Permian salt deposits are characterized by low permeabilities and highly mineralized water. Sandstone of the Delaware Mountain Group, which underlies the salt, has an average hydraulic conductivity of 0.16 ft/d and an average porosity of 15.65 percent. Flow is north-northeastward toward the margin of the Capitan Limestone, at velocities ranging from 0.0005 to 0.0008 ft/d. The Capitan Limestone, a relatively high yielding limestone-reef aquifer adjacent to the study area, has transmissivity values ranging from 500 sq ft/d to 10,000 sq ft/d and an average hydraulic conductivity of about 5 ft/d. Water movement west of the Pecos River is northeastward in the reef, with discharge at Carlsbad Springs. East of the Pecos River, water moves at very low rates and the direction of movement is uncertain. The Castile and Salado Formations, which might be used to contain the nuclear waste, have a few isolated pockets of brine and gas, but generally transmit little or no ground water. (Woodard-USGS)

Open-File Report↗
USGS2007

Science and the storms: The USGS response to the hurricanes of 2005

This report is designed to give a view of the immediate response of the U.S. Geological Survey (USGS) to four major hurricanes of 2005: Dennis, Katrina, Rita, and Wilma. Some of this response took place days after the hurricanes; other responses included fieldwork and analysis through the spring. While hurricane science continues within the USGS, this overview of work following these hurricanes reveals how a Department of the Interior bureau quickly brought together a diverse array of its scientists and technologies to assess and analyze many hurricane effects. Topics vary from flooding and water quality to landscape and ecosystem impacts, from geotechnical reconnaissance to analyzing the collapse of bridges and estimating the volume of debris. Thus, the purpose of this report is to inform the American people of the USGS science that is available and ongoing in regard to hurricanes. It is the hope that such science will help inform the decisions of those citizens and officials tasked with coastal restoration and planning for future hurricanes. Chapter 1 is an essay establishing the need for science in building a resilient coast. The second chapter includes some hurricane facts that provide hurricane terminology, history, and maps of the four hurricanes’ paths. Chapters that follow give the scientific response of USGS to the storms. Both English and metric measurements are used in the articles in anticipation of both general and scientific audiences in the United States and elsewhere. Chapter 8 is a compilation of relevant ongoing and future hurricane work. The epilogue marks the 2-year anniversary of Hurricane Katrina. An index of authors follows the report to aid in finding articles that are cross-referenced within the report. In addition to performing the science needed to understand the effects of hurricanes, USGS employees helped in the rescue of citizens by boat and through technology by “geoaddressing” 911 calls after Katrina and Rita so that other rescuers could find persons trapped in attics and porches. They also delivered food and water to residents stranded along the lower Mississippi River for several days. That work is reported in chapter 3 of this volume. A great number of scientists contributed to this peer-reviewed report designed for a general audience. Because they work for USGS—an unbiased, multidisciplinary science organization that focuses on biology, geography, geology, geospatial information, and water—they are dedicated to the timely, relevant, and impartial study of the landscape and natural resources of the Nation, as well as natural hazards, like hurricanes, that threaten the Nation. To learn more about their work, visit the USGS Web site (www.usgs.gov).

Circular↗