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Articles 391 - 420 of 549

Full-Text Articles in Climate

Droughtscape, Summer 2007, National Drought Mitigation Center Jul 2007

Droughtscape, Summer 2007, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Summer 07 Outlook

Hayes Named Director of NDMC

NDMC & UN Plan for Drought

Book Review: The Worst Hard Time

Drought Tools Workshops Underway

U.S. Drought Monitor Forum October 10-11, 2007 Portland, Oregon


Analysis Of Time-Series Modis 250 M Vegetation Index Data For Crop Classification In The U.S. Central Great Plains, Brian D. Wardlow, Stephen L. Egbert, Jude H. Kastens Jun 2007

Analysis Of Time-Series Modis 250 M Vegetation Index Data For Crop Classification In The U.S. Central Great Plains, Brian D. Wardlow, Stephen L. Egbert, Jude H. Kastens

National Drought Mitigation Center: Faculty Publications

The global environmental change research community requires improved and up-to-date land use/land cover (LULC) datasets at regional to global scales to support a variety of science and policy applications. Considerable strides have been made to improve large-area LULC datasets, but little emphasis has been placed on thematically detailed crop mapping, despite the considerable influence of management activities in the cropland sector on various environmental processes and the economy. Time-series MODIS 250 m Vegetation Index (VI) datasets hold considerable promise for largearea crop mapping in an agriculturally intensive region such as the U.S. Central Great Plains, given their global coverage, intermediate …


Droughtscape, Spring 2007, National Drought Mitigation Center Apr 2007

Droughtscape, Spring 2007, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

2007 Spring Drought Outlook & Winter Summary

VegDRI Expands to 15 States, Refines Views

DroughtScape

State Spotlight: Utah

International Panel Foresees Drought as Part of Climate Change

NIDIS Portal Advancing


Agricultural Climatology, Kenneth G. Hubbard Jan 2007

Agricultural Climatology, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

With the diversification of the U.S. economy over the past century, agriculture has changed. We can say the farm sizes have increased over time, the number of farmers and those employed in farming have decreased over time, and as the economy has grown the relative contribution of agriculture to the total economy has decreased due to growth in other sectors. The farm prices have not changed significantly over many years while costs for energy, machinery, and land have generally increased. The combination of these factors has generally narrowed the profit margin and the highest productivity will no longer ensure the …


Droughtscape, Winter 2007, Kelly Smith Jan 2007

Droughtscape, Winter 2007, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

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Policy Update: NIDIS is Law. What’s Next?

What Would You Like to See?

TX, OK, Plains, Southwest Hardest Hit in 2006

Climatologically Speaking, How Bad Was It?

State Spotlight: Arizona

Drought Decision-Support Tools Evolving


Cold Climate In The Eastern Australian Mid- To Late Permian May Reflect Cold Upwelling Waters, Andrew T. Jones, Tracy D. Frank, Christopher R. Fielding Aug 2006

Cold Climate In The Eastern Australian Mid- To Late Permian May Reflect Cold Upwelling Waters, Andrew T. Jones, Tracy D. Frank, Christopher R. Fielding

Department of Earth and Atmospheric Sciences: Faculty Publications

A suite of ice-rafted dropstones and glendonites throughout the Permian succession of eastern Australia indicates the cold climate associated with the late Paleozoic ice age persisted longest in this part of Gondwana. Paradoxically, these cold climate indicators are preserved in transgressive and highstand facies and formed at mid to high latitudes at a time when paleofloral and sedimentological data suggest equable onshore environments during the intervening lowstands and temperate conditions at the pole. These apparent inconsistencies suggest that eastern Australia was anomalously cold in the context of post-Sakmarian Gondwanan climates, and the distribution of sedimentary indicators could indicate localized cooling …


Project Title: Sustainable Adaptations To Drought And Climate Variability In Agricultural Production Systems Across Nebraska, Cody L. Knutson, Michael J. Hayes, Robert K. Hitchcock, Jeffrey Peake, Martin Kleinschmit Jun 2006

Project Title: Sustainable Adaptations To Drought And Climate Variability In Agricultural Production Systems Across Nebraska, Cody L. Knutson, Michael J. Hayes, Robert K. Hitchcock, Jeffrey Peake, Martin Kleinschmit

National Drought Mitigation Center: Faculty Publications

Drought is a normal part of Nebraska’s climate. It is also the leading cause of monetary disaster loss in the United States. FEMA (1995) has estimated that U.S. drought losses average $6-8 billion dollars per year. A majority of these losses are incurred in the agricultural sector. Nebraska’s losses alone topped $1.2 billion in 2002 (AP 2003).
To enhance viable operations in this variable climate, many Nebraska farmers and ranchers have begun making the transition to agricultural practices that fall into the realm of sustainable agriculture. Sustainability has been increasingly stressed as essential for creating more resilient systems and reducing …


Evidence Of Holocene Climate Change In A Nebraska Sandhills Wetland, Barbara Nicholson, James B. Swinehart Apr 2005

Evidence Of Holocene Climate Change In A Nebraska Sandhills Wetland, Barbara Nicholson, James B. Swinehart

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

The Nebraska Sandhills consist of 50,000 km2 of dunes, currently stabilized by vegetation. Radiocarbon dates of paleosols, blocked paleovalleys, and sand beds found in interdunal wetlands suggest that the Holocene had significant periods of dune reactivation. A paleoecological investigation was conducted in Jumbo Valley, NE, in an interdunal wetland known to contain sand layers interbedded with peat. The sedimentary record in two cores is continuous, except for some loss due to surficial burns. Macrofossils indicate that the late Pleistocene was cool and wet, with current vegetation establishing around 12,000 years ago. Sand and bulk density profiles reveal significant periods …


Multiple-Year Droughts In Nebraska, Michael J. Hayes, Cody L. Knutson, Q. Steven Hu Jan 2005

Multiple-Year Droughts In Nebraska, Michael J. Hayes, Cody L. Knutson, Q. Steven Hu

National Drought Mitigation Center: Faculty Publications

Most people understand that droughts have had a major impact on Nebraska in the past. Yet, many Nebraskans continue to be surprised when drought occurs. It is important to remember that droughts, including multiple-year droughts, are a normal part of Nebraska’s climate. This NebGuide discusses the history of drought in Nebraska, and aims to help Nebraskans better understand the range of climatic variability when they plan for drought.


Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson Jan 2005

Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson

National Drought Mitigation Center: Faculty Publications

Past attempts to manage drought and its impacts through a reactive, crisis management approach have been ineffective, poorly coordinated, and untimely, as illustrated by the hydro- illogical cycle in Figure 1. The crisis management approach has been followed in both developed and developing countries. Because of the ineffectiveness of this approach, greater interest has evolved in recent years in the adoption of a more proactive risk-based management approach in some countries (see Chapter 6). Other countries are striving to obtain a higher level of preparedness through development of national action programs that are part of the United Nations Convention to …


A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes Jan 2005

A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes

National Drought Mitigation Center: Faculty Publications

Droughts are normal climate episodes, yet they are among the most expensive natural disasters in the world. Knowledge about the timing, severity, and pattern of droughts on the landscape can be incorporated into effective planning and decisionmaking. In this study, we present a data mining approach to modeling vegetation stress due to drought and mapping its spatial extent during the growing season. Rule-based regression tree models were generated that identify relationships between satellite-derived vegetation conditions, climatic drought indices, and biophysical data, including land-cover type, available soil water capacity, percent of irrigated farm land, and ecological type. The data mining method …


Discovering Associations Between Climatic And Oceanic Parameters To Monitor Drought In Nebraska Using Data-Mining Techniques, Tsegaye Tadesse, Donald A. Wilhite, Michael J. Hayes, Steve Goddard Jan 2005

Discovering Associations Between Climatic And Oceanic Parameters To Monitor Drought In Nebraska Using Data-Mining Techniques, Tsegaye Tadesse, Donald A. Wilhite, Michael J. Hayes, Steve Goddard

National Drought Mitigation Center: Faculty Publications

Drought is a complex natural hazard that is best characterized by multiple climatological and hydrological parameters. Improving our understanding of the relationships between these parameters is necessary to reduce the impacts of drought. Data mining is a recently developed technique that can be used to interact with large databases and assist in the discovery of associations between drought and oceanic data by extracting information from massive and multiple data archives. In this study, a new data-mining algorithm [i.e., Minimal Occurrences With Constraints and Time Lags (MOWCATL)] has been used to identify the relationships between oceanic parameters and drought indices. Rather …


An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mamood, Kenneth G. Hubbard Jan 2004

An Analysis Of Simulated Long-Term Soil Moisture Data For Three Land Uses Under Contrasting Hydroclimatic Conditions In The Northern Great Plains, Rezaul Mamood, Kenneth G. Hubbard

High Plains Regional Climate Center: Staff Publications

Soil moisture (SM) plays an important role in land surface and atmosphere interactions. It modifies energy balance near the surface and the rate of water cycling between land and atmosphere. The lack of observed SM data prohibits understanding of SM variations at climate scales under varying land uses. However, with simulation models it is possible to develop a long-term SM dataset and study these issues. In this paper a water balance model is used to provide a quantitative assessment of SM climatologies for three land uses, namely, irrigated corn, rain-fed corn, and grass, grown under three hydroclimatic regimes in Nebraska. …


An Agricultural Drought Risk-Assessment Model For Corn And Soybeans, Hong Wu, Kenneth G. Hubbard, Donald A. Wilhite Jan 2004

An Agricultural Drought Risk-Assessment Model For Corn And Soybeans, Hong Wu, Kenneth G. Hubbard, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

Copyright © 2004 Royal Meteorological Society. Published by Wiley InterScience. Used by permis-sion.


An Operational Agricultural Drought Risk Assessment Model For Nebraska, Usa, Hong Wu, Donald A. Wilhite Jan 2004

An Operational Agricultural Drought Risk Assessment Model For Nebraska, Usa, Hong Wu, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

Drought is a common occurrence in Nebraska and agriculture is the primary economic sector affected. Because of repeated and widespread severe drought impacts, more emphasis on drought risk management is warranted. This study develops an agricultural drought risk assessment model using multivariate techniques. The model is specific to corn and soybeans and is able to assess real-time agricultural drought risk associated with crop yield losses at critical phenological stages prior to and during the growing season. The assessment results are presented in a Geographic Information System to provide a better visualization. This model provides information in a timely manner about …


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

National 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 …


Recent Advances In Drought Monitoring, Mark D. Svoboda, Michael J. Hayes, Donald A. Wilhite, Tsegaye Tadesse Jan 2004

Recent Advances In Drought Monitoring, Mark D. Svoboda, Michael J. Hayes, Donald A. Wilhite, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

Recent widespread, severe, and long-lasting droughts across North America have heightened awareness of and interest in how to better monitor drought and its impacts. Since its inception in 1999, the National Drought Mitigation Center (NDMC), United States Department of Agriculture (USDA) and NOAA’s Climate Prediction Center (CPC) and National Climatic Data Center (NCDC) have partnered to produce the weekly U.S. Drought Monitor (http://droug ht.unl.edu/m onitor/), a comprehensive drought assessment product based on a simple 5- category severity classification. On the heels of its widespread acceptance and usage, the NCDC, CPC, USDA, NDMC and scientists from Canada and Mexico have worked …


A Geospatial Decision Support System For Drought Risk Management, Steve Goddard, Jitender Deogun, Sherri K. Harms, Michael J. Hayes, Kenneth G. Hubbard, Stephen Reichenbach, Peter Revesz, W. J. Waltman, Donald A. Wilhite Jan 2004

A Geospatial Decision Support System For Drought Risk Management, Steve Goddard, Jitender Deogun, Sherri K. Harms, Michael J. Hayes, Kenneth G. Hubbard, Stephen Reichenbach, Peter Revesz, W. J. Waltman, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

Drought affects virtually all regions of the world and results in significant economic, social, and environmental impacts. The Federal Emergency Management Agency estimates annual drought-related losses in the United States at $6-8 billion, which is more than any other natural hazard. Congress enacted the Agricultural Risk Protection Act of 2000 to encourage the United States Department of Agriculture (USDA) Risk Management Agency (RMA) and farmers to be more proactive in managing drought risk. Through the National Science Foundation (NSF) Digital Government program, the USDA RMA is working with the University of Nebraska−Lincoln Computer Science and Engineering (CSE) Department, National Drought …


Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe Jan 2003

Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe

United States Geological Survey: Staff Publications

Elemental abundances and Nd and Pb isotope ratios were determined on samples from the carbonate-free, clay-size fractions of sediments from intervals above, within, and below Heinrich event 2 (H-2) in core HU87-9 from the Northwest Labrador Sea slope. In HU87-9, rare-earth element (REE) distributions and elemental concentrations within the H-2 event are distinct from those outside this event. ɛNd(0) and 206Pb/204Pb data also indicate different values for sediments deposited within and outside the H-2 event. Comparisons of REE patterns from the H-2 interval with those from bedrock units in Baffin Island, northern Quebec, and Labrador …


Beginning A New Era Of Drought Monitoring Across North America, Jay Lawrimore, Richard R. Heim Jr., Mark D. Svoboda, Val Swail, Phil J. Englehart Jul 2002

Beginning A New Era Of Drought Monitoring Across North America, Jay Lawrimore, Richard R. Heim Jr., Mark D. Svoboda, Val Swail, Phil J. Englehart

National Drought Mitigation Center: Faculty Publications

Drought experts from the United States, Canada, and Mexico met at the National Climatic Data Center in Asheville, North Carolina, for a three-day workshop in late April 2002 to discuss the United States Drought Monitor program and to develop a plan for initiating a new program of drought monitoring for North America. Since its inception in 1999, the U.S. Drought Monitor (DM) has been extremely successful in assessing and communicating the state of drought in the United States on a weekly basis. This success, and the recognition that an ongoing comprehensive and integrated drought assessment was needed throughout all three …


Three Years And Counting: What’S New With The Drought Monitor, Mark D. Svoboda, Michael J. Hayes, Rich J. Tinker May 2002

Three Years And Counting: What’S New With The Drought Monitor, Mark D. Svoboda, Michael J. Hayes, Rich J. Tinker

National Drought Mitigation Center: Faculty Publications

Operational since late summer 1999, the Drought Monitor (http://drought.unl.edu/monitor/) has refused to remain static. This unique weekly product attempts to make an assessment of current drought conditions in the contiguous United States, Hawaii, Alaska, and Puerto Rico. Four entities now share in authoring the map: the National Drought Mitigation Center (NDMC), Climate Prediction Center (CPC), United States Department of Agriculture (USDA), and National Climatic Data Center (NCDC).
The Drought Monitor effort has led to the development of new products and has reinforced the need for improvement and support of existing climate networks critical to monitoring our nation’s climate. One of …


The Drought Monitor, Mark D. Svoboda, Doug Lecomte, Mike Hayes, Richard Heim, Karin Gleason, Jim Angel, Brad Rippey, Rich Tinker, Mike Palecki, David Stooksbury, David Miskus, Scott Stephens Apr 2002

The Drought Monitor, Mark D. Svoboda, Doug Lecomte, Mike Hayes, Richard Heim, Karin Gleason, Jim Angel, Brad Rippey, Rich Tinker, Mike Palecki, David Stooksbury, David Miskus, Scott Stephens

National Drought Mitigation Center: Faculty Publications

There is a need for improved drought monitoring and assessment methods in the United States. Drought is the most costly natural disaster [Federal Emergency Management Agancy (FEMA 1995; Wilhite 2000)], but it is often neglected by developers of assessment and forecast products. Drought is more nebulous than other disasters and does not lend itself to traditional assessments or forecast methods. Its relatively slow onset and the complexity of its impacts are reasons for the new assessment methodology. Improvements in drought monitoring and forecasting techniques will allow for better preparation, lead to better management practices, and reduce the vulnerability of society …


Assessing Vulnerability To Agricultural Drought: A Nebraska Case Study, Olga V. Wilhelmi, Donald A. Wilhite Jan 2002

Assessing Vulnerability To Agricultural Drought: A Nebraska Case Study, Olga V. Wilhelmi, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

Recent drought events in the United States and the magnitude of drought losses indicate the continuing vulnerability of the country to drought. Until recently, drought management in many states, including Nebraska, has been largely response oriented with little or no attention to mitigation and preparedness. In 1998, Nebraska began to revise its drought plan in order to place more emphasis on mitigation. One of the main aspects of drought mitigation and planning is the assessment of who and what is vulnerable and why. This paper presents a method for spatial, Geographic Information Systems-based assessment of agricultural drought vulnerability in Nebraska. …


Spatial Representation Of Agroclimatology In A Study Of Agricultural Drought, Olga V. Wilhelmi, Kenneth Hubbard, Donald A. Wilhite Jan 2002

Spatial Representation Of Agroclimatology In A Study Of Agricultural Drought, Olga V. Wilhelmi, Kenneth Hubbard, Donald A. Wilhite

National Drought Mitigation Center: Faculty Publications

Agricultural drought is the leading cause for crop failure throughout the world. In the USA, significant impacts of recent droughts on agricultural production indicate the continuing vulnerability of the country to drought. This paper presents a methodology for spatial representation of the agroclimatic component of agricultural drought vulnerability. This methodology was developed as a part of an integrated assessment of drought vulnerability. For the spatial analysis, the state of Nebraska was selected as a study area because of the considerable variation in climatology, soil characteristics, land use, and cropping patterns. The underlying approach assumes that the best spatial characterization of …


Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson Jan 2002

Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson

High Plains Regional Climate Center: Staff Publications

The North American Great Plains have experienced a rapid overturning of natural grasslands to agricultural land use over the last century. Moreover, in some areas more than 80% of the land use has changed from dry land to irrigated agriculture during the second half of the twentieth century. It is speculated that these changes have modified near-surface atmospheric condition and our modeling study seems to support this. To identify changes in land surface- atmospheric modifications we have applied a soil moistureenergy balance model at three locations in Nebraska: Mead, York, and McCook. The model was applied for three land uses …


Strontium Isotopic Signatures Of The Streams And Lakes Of Taylor Valley, Southern Victoria Land, Antarctica: Chemical Weathering In A Polar Climate, W. B. Lyons, Carmen A. Nezat, Larry V. Benson, Thomas D. Bullen, Elizabeth Y. Graham, Jesicca Kidd, Kathleen A. Welch, James M. Thomas Jan 2002

Strontium Isotopic Signatures Of The Streams And Lakes Of Taylor Valley, Southern Victoria Land, Antarctica: Chemical Weathering In A Polar Climate, W. B. Lyons, Carmen A. Nezat, Larry V. Benson, Thomas D. Bullen, Elizabeth Y. Graham, Jesicca Kidd, Kathleen A. Welch, James M. Thomas

United States Geological Survey: Staff Publications

We have collected and analyzed a series of water samples from three closed-basin lakes (Lakes Bonney, Fryxell, and Hoare) in Taylor Valley, Antarctica, and the streams that flow into them. In all three lakes, the hypolimnetic waters have different 87Sr/86Sr ratios than the surface waters, with the deep water of Lakes Fryxell and Hoare being less radiogenic than the surface waters. The opposite occurs in Lake Bonney. The Lake Fryxell isotopic ratios are lower than modern-day ocean water and most of the whole-rock ratios of the surrounding geologic materials. A conceivable source of Sr to the system …


Poor Water Resources And Drought In The Gujarat/Saurashtra Regions Of India, K. K. Nathan Oct 2001

Poor Water Resources And Drought In The Gujarat/Saurashtra Regions Of India, K. K. Nathan

Drought Network News (1994–2001)

Inadequate water resources pose a big threat to the economy, human activities, and livelihood in the Gujarat/Saurashtra regions of India. Scanty rainfall with wide aberrations in its distribution has made the situation worse, leading to chronic drought in the state in 2001. With the exception of the Narmada and Tapi rivers, there are hardly any water resources to sustain agricultural production in the region. The gradual disappearance of forest cover in the state has further aggravated the drought situation. This has led to large-scale erosion of the topsoil, particularly near the riverside. There is apprehension that the region will soon …


Creating A Network Of Regional Drought Preparedness Networks: A Call For Action, Donald A. Wilhite Oct 2001

Creating A Network Of Regional Drought Preparedness Networks: A Call For Action, Donald A. Wilhite

Drought Network News (1994–2001)

Drought is a creeping, slow-onset natural hazard that is a normal part of climate for virtually all regions of the world; it results in serious economic, social, and environmental impacts. Its onset and end are often difficult to determine, as is its severity. Drought affects more people than any other natural hazard. Lessons from developed and developing countries demonstrate that drought results in significant impacts, regardless of level of development, although the character of these impacts will differ profoundly. At the Meeting on Opportunities for Sustainable Investment in Rainfed Areas of West Asia and North Africa (WANA), held in June …


Announcements: Summer/Fall 2001 Jul 2001

Announcements: Summer/Fall 2001

Drought Network News (1994–2001)

Contents:

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World

Defending the Integrity of Ground Water: Understanding the Impacts of Natural and Manmade Disasters

Conference on Energy Climate, Environment and Water—Issues and Opportunities for Irrigation and Drainage


An Analysis Of Recent Drought Conditions In Turkey In Relation To Circulation Patterns, Ali Umran Komuscu Jun 2001

An Analysis Of Recent Drought Conditions In Turkey In Relation To Circulation Patterns, Ali Umran Komuscu

Drought Network News (1994–2001)

Drought commonly is perceived to be a prolonged period with a significant reduction in precipitation. Namias (1985) argues that drought is associated with persistent or persistently recurring atmospheric circulation patterns. For example, the North Atlantic Oscillation (NAO) has a major role in controlling European climate and appears to exert a strong influence in modulating North Atlantic ecosystems. During the positive phases of NAO, the North Atlantic westerlies, which provide much of the atmospheric moisture to north Africa and Europe, shift northward. This, in turn, results in drier conditions over southern Europe, the Mediterranean Sea, and northern Africa (Hurrell, 1995; Hurrell …