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Abstract (from http://link.springer.com/article/10.1007/s11069-016-2376-z): Drought is among the most insidious types of natural disasters and can have devastating economic and human health impacts. This research analyzes the relationship between two readily accessible drought indices—the Palmer Drought Severity Index (PDSI) and Palmer Hydrologic Drought Index (PHDI)—and the damage incurred by such droughts in terms of monetary loss, over the 1975–2010 time period on monthly basis, for five states in the south-central USA. Because drought damage in the Spatial Hazards Events and Losses Database for the United States (SHELDUS™) is reported at the county level, statistical downscaling techniques were used to estimate...
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Drought is a natural hazard that inflicts costly damage to the environment and human communities. Although ample literature exists on the climatological aspects of drought, little is known on whether existing drought indices can predict the damages and how different human communities respond and adapt to the hazard. This project examines (1) whether existing drought indices can predict the occurrence of drought events and their actual damages; (2) how the adaptive capacity (i.e., resilience) varies across space; and (3) what public outreach and engagement effort would be most effective for mitigation of risk and impacts. The study region includes all 503 counties in Arkansas, Louisiana, New Mexico, Oklahoma, and...
Historically, drought has been viewed in terms of its agricultural, hydrological, and socioeconomic impacts. How drought affects ecosystems - and the services they provide human communities - is often not discussed. In response, the U.S. Geological Survey's National Climate Adaptation Science Center (NCASC) initiated a national-scale effort that’s addressing this gap in drought research. A new concept – ecological drought – was defined as part of this effort. This geo-narrative explains the concept of ecological drought, and highlights the research and products that were initiated as part of this effort.
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It is well understood that plant phenology is sensitive to climate, however it is not so clear exactly how climate change might alter the spatial and temporal patterns of vegetation phenology. Satellite remote sensing offers a unique vantage point from which to observe phenological cycles across large regions. Although ubiquitous, cycles of green-up and brown-down are complex and exhibit great variability across space and time. Herbivore species such as elk, moose, and deer depend on the availability of herbaceous plants and deciduous shrubs for forage. These vegetation types are most nutritious for herbivores from early season to peak green-up, so characterizing vegetation cycles, or phenology, over the long term...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-15-0042.1): Drought is a natural part of the historical climate variability in the northern Rocky Mountains and high plains region of the United States. However, recent drought impacts and climate change projections have increased the need for a systematized way to document and understand drought in a manner that is meaningful to public land and resource managers. The purpose of this exploratory study was to characterize the ways in which some federal and tribal natural resource managers experienced and dealt with drought on lands managed by the U.S. Department of the Interior (DOI) and tribes in two case site examples (northwest Colorado and southwest...
The Wind River Indian Reservation (WRIR) in west-central Wyoming is home to the Eastern Shoshone and Northern Arapaho tribes, who reside near and depend on water from the streams that feed into Wind River. In recent years, however, the region has experienced frequent severe droughts, which have affected tribal livelihoods and cultural activities. Scientists with the North Central Climate Adaptation Science Center (NCCASC) at Colorado State University, the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, and several other university and agency partners in the region worked in close partnership with tribal water managers to assess how drought affects the reservation, which included...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12847/full): Climate models predict increasing drought intensity and frequency for many regions, which may have negative consequences for tree recruitment, growth and mortality, as well as forest ecosystem services. Furthermore, practical strategies for minimizing vulnerability to drought are limited. Tree population density, a metric of tree abundance in a given area, is a primary driver of competitive intensity among trees, which influences tree growth and mortality. Manipulating tree population density may be a mechanism for moderating drought-induced stress and growth reductions, although the relationship between tree population density and...
This 2-pager describes the Evaporative Demand Drought Index (EDDI), which is a drought index that can serve as an indicator of both rapidly evolving “flash” droughts (developing over a few weeks) and sustained droughts (developing over months but lasting up to years).
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The South Central U.S. is one of the main agricultural regions in North America: annual agricultural production is valued at more than $44 billion dollars. However, as climate conditions change, the region is experiencing more frequent and severe droughts, with significant impacts on agriculture and broader consequences for land management. For example, in 2011 drought caused an estimated $7.6 billion in agricultural losses in Texas and an additional $1.6 billion in Oklahoma. Although there are many drought monitoring tools available, most of these tools were developed without input from the stakeholders, such as farmers and ranchers, who are intended to use them. The goal of this project is to assess the information...
Abstract (from AGU100): Forest conservation and carbon sequestration efforts are on the rise, yet the long‐term stability of these efforts under a changing climate remains unknown. We generate nearly three decades of remotely sensed canopy water content throughout California, which we use to determine patterns of drought stress. Linking these patterns of drought stress with meteorological variables enables us to quantify spatially explicit biophysical drought resistance in terms of magnitude and duration. These maps reveal significant spatial heterogeneity in drought resistance and demonstrate that almost all forests have less resistance to severe, persistent droughts. By identifying the spatial patterning of biophysical...
The responses of individual species to environmental changes can be manifested at multiple levels that range from individual-level (i.e., behavioral responses) to population-level (i.e., demographic) impacts. Major environmental changes that ultimately result in population level impacts are often first detected as individual-level responses. For example, herbivores respond to limited forage availability during drought periods by increasing the duration of foraging periods and expanding home range areas to compensate for the reduction in forage. However, if the individual-level responses are not sufficient to compensate for reduced forage availability, reduced survival and reproductive rates may result. We studied...
The responses of individual species to environmental changes can be manifested at multiple levels that range from individual-level (i.e., behavioral responses) to population-level (i.e., demographic) impacts. Major environmental changes that ultimately result in population level impacts are often first detected as individual-level responses. For example, herbivores respond to limited forage availability during drought periods by increasing the duration of foraging periods and expanding home range areas to compensate for the reduction in forage. However, if the individual-level responses are not sufficient to compensate for reduced forage availability, reduced survival and reproductive rates may result. We studied...
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JAMC-D-15-0167.1): Annual precipitation in California is more variable than in any other state and is highly influenced by precipitation in winter months. A primary question among stakeholders is whether low precipitation in certain months is a harbinger of annual drought in California. Historical precipitation data from 1895 to 2013 are investigated to identify leading monthly indicators of annual drought in each of the seven climate divisions (CDs) as well as statewide. For this study, drought conditions are defined as monthly/annual (October–September) precipitation below the 20th/30th percentile, and a leading indicator is defined as a monthly drought...
Severe droughts cause widespread tree mortality and decreased growth in forests across the globe. Forest managers are seeking strategies to increase forest resistance (minimizing negative impacts during the drought) and resilience (maximizing recovery rates following drought). Limited experimental evidence suggests that forests with particular structural characteristics have greater capacity to resist change and or recover ecosystem function in the face of drought. However, the applicability of these results to practical forest conservation and management remains unclear. This project utilized an existing network of eight long-term, operational-scale, forest management experiments from Arizona to Maine to examine...
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 potential agricultural drought risks on...
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The threat of droughts and their associated impacts on the landscape and human communities have long been recognized in the United States, especially in high risk areas such as the southcentral region. This project examines whether existing drought indices can predict the occurrence of drought events and their actual damages, how the adaptive capacity (i.e., resilience) varies across space, and what public outreach and engagement effort would be most effective for mitigation of risk and impacts. The study region includes all 503 counties in Arkansas, Louisiana, New Mexico, Oklahoma, and Texas. This data set was created to assess the community resilience to the drought hazards using the Resilience Inference Measurement...
Drought indices are widely used for drought monitoring. This study evaluates the performance of six indices (Palmer’s Drought Severity Index (PDSI), Palmer’s Z-index, precipitation percent normal, precipitation percentiles, Standardized Precipitation Index (SPI), and the Standardized Precipitation Evapotranspiration Index (SPEI)) to determine which are most appropriate for monitoring agricultural drought in the south-central United States. Soil moisture and crop yield data for winter wheat, corn and cotton are used to assess the performance of drought indices. The results indicate that SPEI is the most representative of soil moisture conditions. The best drought index for crop yield varies depending on crop type...
Although tropical Pacific islands are generally perceived as having wet climates, they are vulnerable to periodic episodes of drought. This literature review strives to establish a base of information relating to such drought events in the U. S.- affiliated Pacific Islands (USAPI), a vast expanse of the oceanic Pacific larger than the North American continent, spanning five time zones and the International Date Line roughly between the southern Tropic of Capricorn across the equator to the northern Tropic of Cancer. The USAPI include the Territories of American Samoa and Guam, Commonwealth of the Northern Mariana Islands, and the Freely Associated States of the Republic of Palau, Federated States of Micronesia,...
map background search result map search result map The Effects of Drought on Vegetation Phenology and Wildlife Combined county-level drought incidence, damage, and census data County-level drought indices The Palmer Drought Severity Index(PDSI)and Palmer Hydrological Drought Index(PHDI) Drought Indicators of the South Central Plains (1981-2014) The Effects of Drought on Vegetation Phenology and Wildlife Drought Indicators of the South Central Plains (1981-2014) Combined county-level drought incidence, damage, and census data County-level drought indices The Palmer Drought Severity Index(PDSI)and Palmer Hydrological Drought Index(PHDI)