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Environmental Indicators and Impact Assessment

Drought

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Articles 31 - 45 of 45

Full-Text Articles in Physical Sciences and Mathematics

Rangeland Responses To Predicted Increases In Drought Extremity, David D. Breshears, Alan K. Knapp, Darin J. Law, Melinda D. Smith, Dirac L. Twidwell, Carissa L. Wonkka Jan 2016

Rangeland Responses To Predicted Increases In Drought Extremity, David D. Breshears, Alan K. Knapp, Darin J. Law, Melinda D. Smith, Dirac L. Twidwell, Carissa L. Wonkka

Drought Mitigation Center: Faculty Publications

Rangeland managers actively focus on the potential to induce a shift in a site to an alternative state, but predicted changes in climate, particularly the likelihood of more extreme drought, necessitate reevaluating risks for alternative states. • Rangelands will differ in their susceptibility to undergo state changes due to climate change in general and for droughts of the future, in particular, which may be hotter. • Trees, shrubs, and grasses are expected to differ in their sensitivity to drought, with trees likely being most sensitive; this affects the likelihood for state changes in grasslands, shrublands, woodlands, and savannas. • Considering …

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U.S. Drought Monitor, May 26, 2015, Brad Rippey May 2015

U.S. Drought Monitor, May 26, 2015, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for May 26, 2015 (5/26/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

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Three Essays On Biofuels, Drought, Livestock, And The Environment, Sunil P. Dhoubhadel Apr 2015

Three Essays On Biofuels, Drought, Livestock, And The Environment, Sunil P. Dhoubhadel

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This dissertation consists of three essays. The first essay examines the impact of the 2012 drought and the biofuels mandate on the U.S. grain and livestock markets. A stochastic equilibrium displacement model is used to analyze the impact on eight commodity markets viz. beef, pork, poultry, corn, distillers’ grain (DG), soybean, soymeal, and ethanol. Among the eight markets, corn and beef are found to be the most vulnerable to drought. The use of Renewable Identification Number (RIN) credits as an instrument to mitigate the impact of drought has limited effectiveness. A mandate waiver of about 23% is required to fully …

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On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell Jan 2015

On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell

United States Geological Survey: Staff Publications

Patterns, mechanisms, projections, and consequences of tree mortality and associated broadscale forest die-off due to drought accompanied by warmer temperatures—‘‘hotter drought’’, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortalityrelevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases …

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San Diego’S Options For Alternate Sources Of Water: A Comparative Analysis Of Water Recycling And Desalination As Alternative Methods To Importing Water, Alana O. Pokorny Jan 2015

San Diego’S Options For Alternate Sources Of Water: A Comparative Analysis Of Water Recycling And Desalination As Alternative Methods To Importing Water, Alana O. Pokorny

Scripps Senior Theses

This paper describes the processes, methods, backgrounds, and economic challenges, of Desalination and Water Recycling and provide current examples of both. To create a baseline with which to compare the two methods, I will also delve into the history of California water policy. This complicated past is the reason water importation into Southern California remains the main method of obtaining water. Yet, as the current drought continues and technology advances, the need for imported water will become obsolete as the methods for recycling and desalinating water become less expensive, more convenient and more equitable. In the conclusion, all the methods …

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A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett Jan 2015

A Historical Perspective On Nebraska’S Variable And Changing Climate, Martha Shulski, William Baule, Crystal J. Stiles, Natalie A. Umphlett

High Plains Regional Climate Center: Personnel Publications

Nebraska is situated at the intersection of the northern and southern Great Plains, exhibiting a dramatic longitudinal gradient for precipitation and humidity, and benefiting from groundwater resources. The continental climate is highly variable temporally both for temperature and precipitation. Our assessment of long-term meteorological observations shows that over the last century the annual average temperature in Nebraska has warmed approximately 0.6°C, which is similar to the increase in the global average temperature over the same time period. Furthermore, we found minimum temperatures have warmed more than maximum temperatures, and winter and spring show the strongest warming. We found no significant …

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Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker Jan 2014

Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

School of Natural Resources: Faculty Publications

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS sensors. …

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Drought Triggers And Declarations: Science And Policy Considerations For Drought Risk Management, Linda Courtenay Botterill, Michael J. Hayes Jan 2012

Drought Triggers And Declarations: Science And Policy Considerations For Drought Risk Management, Linda Courtenay Botterill, Michael J. Hayes

Drought Mitigation Center: Faculty Publications

This paper explores the value of triggers and declarations in the management of drought, bringing together two disciplinary perspectives, those of the public policy scholar and the climate scientist. These two perspectives highlight the complexity of the development and use of triggers in drought risk management by drawing on the experience of the United States, which has the most sophisticated system of drought triggers in the world, and that of Australia that has the most developed and longest standing national drought policy based on principles of risk management. The paper explores the advantages and disadvantages of triggers in managing drought, …

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Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto Dec 2011

Global Effects Of Climate Change On Wildfire: Causal Relationships Of Fire, The Natural Environment And Human Activities, Lindon N. Pronto

Lindon N Pronto

Climate change and human activity is significantly impacting the frequency and severity of wildfires across the globe. Although climate change and human population are the overarching factors affecting wildfires in the current dialogue, the issues are more complex and often not fully understood. These issues range from global temperature increases and severe drought cycles to the relatively new phenomenon of the wildland urban interface (WUI). This is the area where structures are integrated with or immediately surrounded by areas of moderate to high fire risk and are directly linked to fuel types and topographic features. Because climate change is such …

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Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf Jan 2011

Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf

Drought Mitigation Center: Faculty Publications

Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …

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Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff Jan 2010

Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff

Drought Mitigation Center: Faculty Publications

Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioral traits, what time periods and indicators of drought are most relevant, or how response varies geographically at broad spatial scales. Our goals were thus to determine (1) how avian abundance and species richness are related to drought, (2) whether community variations are more related to vegetation vigor or precipitation deviations and at what time periods relationships …

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Drought Monitoring Using Data Mining Techniques: A Case Study For Nebraska, Usa, Tsegaye Tadesse, Donald A. Wilhite, Sherri K. Harms, Michael J. Hayes, Steve Goddard Jan 2004

Drought Monitoring Using Data Mining Techniques: A Case Study For Nebraska, Usa, Tsegaye Tadesse, Donald A. Wilhite, Sherri K. Harms, Michael J. Hayes, Steve Goddard

Drought Mitigation Center: Faculty Publications

Drought has an impact on many aspects of society. To help decision makers reduce the impacts of drought, it is important to improve our understanding of the characteristics and relationships of atmospheric and oceanic parameters that cause drought. In this study, the use of data mining techniques is introduced to find associations between drought and several oceanic and climatic indices that could help users in making knowledgeable decisions about drought responses before the drought actually occurs. Data mining techniques enable users to search for hidden patterns and find association rules for target data sets such as drought episodes. These techniques …

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Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty Jan 1998

Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty

Peer Reviewed Publications

Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …

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Klamath Basin: Balancing Instream Flows With Irrigation And Power, Carl Ullman Jun 1997

Klamath Basin: Balancing Instream Flows With Irrigation And Power, Carl Ullman

Dams: Water and Power in the New West (Summer Conference, June 2-4)

15 pages (includes illustrations and maps).

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An Investigation Of Surface Albedo Variations During The Recent Sahel Drought, Carl C. Norton, Frederick R. Mosher, Barry Hinton Oct 1979

An Investigation Of Surface Albedo Variations During The Recent Sahel Drought, Carl C. Norton, Frederick R. Mosher, Barry Hinton

Publications

Applications Technology Satellite (ATS) 3 green sensor data are used to measure surface reflectance variations in the Sahara/Sahel during the recent drought period 1967–74. The magnitude of the seasonal reflectance change is shown to be as much as 80% for years of normal precipitation and less than 50% for drought years. Year-to-year comparisons during both wet and dry seasons reveal the existence of a surface reflectance cycle coincident with the drought intensity. The relationship between the green reflectance and solar albedo is examined and estimated to be about 0.6 times the reflectance change observed by the green channel.

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