Drought Mitigation Strategies Research Articles

Risk analysis and evaluation of agricultural drought disaster in the major grain-producing areas, China

ABSTRACTThe analysis and evaluation of agricultural drought risk can assist in reducing regional disasters and agricultural drought losses. Because of the uncertainties and incomplete agricultural drought information, this paper employed an information diffusion technology and information matrix to identify a drought disaster risk distribution and to quantify the relationship between the annual drought-affected rate and the grain production losses in China's major grain-producing areas. From the assessment results, provincial drought disaster risk spatial distribution maps for each major grain-producing area in China were obtained. These risk patterns showed that the probability of drought fell when the annual drought-covered rate and the annual drought-affected rate increased, and that the high risk areas were located primarily in China's northern and central provinces. These results can provide the basis for the development of effective drought mitigation strategies which would be able to inform possible drought situations and allow for easier decision-making on drought resistance strategies. The fuzzy relationship between the annual drought-affected rate and the drought-caused grain production losses provides vital information for the development of disaster compensation plans. Furthermore, the results of this study indicated that the proposed methods had superior detection stability and higher precision. We hope that by conducting such agricultural drought risk analysis, the results are able to provide the basis for the development of drought mitigation strategies to reduce future losses.

Integrated drought causality, hazard, and vulnerability assessment for future socioeconomic scenarios: An information theory perspective

AbstractDrought properties and the socioeconomic impact it makes are expected to increase in the coming years due to climate change. Here we review the possible impacts of changes in climate variability on the properties of different drought types. The downscaled and bias‐corrected data from five general circulation models (GCMs) were used to produce an ensemble of precipitation, temperature, and wind speed, through a relative entropy approach and were used for drought analysis. A novel Multivariate Drought Index was then employed for an integrated quantification of all physical forms of drought. We studied the spatial patterns of drought properties and performed multivariate frequency analysis for each planning region in Texas to recognize the distribution of potential drought hazard areas under climate change impact by formulating a Drought Hazard Index. A drought vulnerability assessment was also carried out by taking into consideration various socioeconomic factors, leading to the development of socioeconomic Drought Vulnerability Index. A set of composite drought risk maps that combines hazard and vulnerability analysis were developed. This study also explored the cause‐effect relationship between the drought events and several hydroclimatic triggers. A transfer entropy measure was used to quantify the causal relationships, thus indicating the predominant future drought triggers. Overall, the findings are expected to help achieve an effective drought mitigation strategy for the state of Texas.

Effects of large-scale climate patterns and human activities on hydrological drought: a case study in the Luanhe River basin, China

Evaluation of the impact of climate variability and human activities on hydrological drought is of great significance for drought mitigation strategies. In this study, standardized runoff index (SRI) at various time scales is used to characterize hydrological droughts in the Luanhe River basin, northeast of China, for the period of 1959–2011. Correlation analysis is conducted to examine the associations between the hydrological droughts and large-scale oceanic–atmospheric patterns (AMO and ENSO). Climate-induced and human-induced influence indices are also developed based on standardized precipitation index and SRI to investigate the possible influences of the climate patterns and human activities on the hydrological droughts. Results indicate that the significant influence of AMO on hydrological drought at different time scales is evident among different months across the Luanhe River basin, with warm (cold) AMO phases favoring drought (wet) conditions. The direct linkage of ENSO to hydrological drought is relatively weak in the basin, while the extent of the linkage can be improved with increasing time lags. Moreover, El Nino phases show a closer relation with the drought events of the region as compared with La Nina phases. It is also implied that human activities exhibit aggravating effects on hydrological drought at shorter time scales over the basin, whereas they might show mitigating effects at longer time scales in some areas of the basin. These findings can be beneficial for better understanding how the hydrological drought responses to climate changes and human activities, thereby providing valuable references for drought forecasts and water resources managements in the Luanhe River basin.

SPATIO-TEMPORAL VARIATION OF AGRICULTURAL DROUGHT IN THE BARIND REGION OF BANGLADESH: AN APPLICATION OF A MARKOV CHAIN MODEL

The Barind region of Bangladesh is severely affected by agricultural drought. A geostatistical approach had been conducted to summarize the spatio-temporal variation of agricultural drought in this region. A Markov chain model of higher order has been used to evaluate probabilities of getting a sequence of wet–dry weeks over this region from the rainfall data recorded in 12 rainfall gauge stations for the period 1971–2008. A drought index (DI) considering crucial parameters (DI = 0 ~ 1.00) has been used to estimate the severity of agricultural drought. Geospatial analysis has been conducted to delineate the spatial extent of agricultural drought of different severities in different seasons. The probability of three consecutive dry weeks and probability of at least 10 and 12 weeks was also calculated to find out the suitability of agricultural production. The maximum variation of agricultural drought index (DI = 0.12 ~ 0.43) was found during the pre-kharif (March to May) and kharif (June to October) (DI = 0.47 ~ 0.81) seasons. However, no variation in drought index (DI = 0.01 ~ 0.03) was found during the rabi (November to February) season. The results of this study might be useful to agricultural planners and irrigation engineers in identifying areas where agricultural development should be focused as a long-term drought mitigation strategy. Copyright © 2013 John Wiley & Sons, Ltd.

Artificial neural networks models for predicting effective drought index: Factoring effects of rainfall variability

Though most factors that trigger droughts cannot be prevented, accurate, relevant and timely forecasts can be used to mitigate their impacts. Drought forecasts must define the droughts severity, onset, cessation, duration and spatial distribution. Given the high probability of droughts occurrence in Kenya, her heavy reliance on rain-fed agriculture and lack of effective drought mitigation strategies, the country is highly vulnerable to impacts of droughts. Current drought forecasting approaches used in Kenya are not able to provide short and long term forecasts and they fall short of providing the severity of the drought. In this paper, a combination of Artificial Neural Networks and Effective Drought Index is presented as a potential candidate for addressing these drawbacks. This is demonstrated using forecasting models that were built using weather data for thirty years for four weather stations (representing 3 agro-ecological zones) in Kenya. Experiments varying various input/output combinations were carried out and drought forecasting network models were implemented in Matrix Laboratory’s (MATLAB) Neural Network Toolbox. The models incorporate forecasted rainfall values in order to mitigate for unexpected extreme climate variations. With accuracies as high as 98 %, the solution is a great enhancement to the solutions currently in use in Kenya.

Analysis of meteorological drought in northwest Iran using the Joint Deficit Index

Summary Probabilistic assessment and prediction of drought provides valuable information for water resources planners and policy makers for developing drought mitigation strategies. In this study an evaluation of drought conditions in northwest of Iran was performed by means of the Joint Deficit Index (JDI). Monthly precipitation data from 1970 to 2007 based on 50 gauge stations uniformly distributed across the area were used for calculating the JDI. Results show that the JDI provides a comprehensive assessment of droughts and that it is capable of reflecting both emerging and prolonged droughts reported in the data. Furthermore, the method provides a basis for determining the amount of precipitation required to reach normal conditions in future months (1–3 months examined in this study), and the exceedance probability of this precipitation amount. Performance evaluation based on 6 years of independent precipitation data from the region showed Critical Success Index of 0.61 (0.64) for the 1-month (3-month) ahead prediction of the drought conditions. The analysis in this study indicated a good skill in predicting the evolution of drought conditions for the region based on JDI evaluated from monthly precipitation data.

Planning for drought-resilient communities: An evaluation of local comprehensive plans in the fastest growing counties in the US

Drought is one of the most frequent and destructive hazards around the world. Recent droughts in the United States have revealed the increasing vulnerability of the nation to this hazard. Since the damages and costs occur at the local levels, local capacity in preparing for drought is our main concern. This study examines 81 local comprehensive plans for the 100 fastest growing counties in the US by systematically evaluating these local comprehensive plans against an evaluation protocol of what makes a drought-ready community. Results show that these fast growing counties have inadequate factual basis, unclear goals and objectives, limited policies, and weak coordination and implementation for potential drought events in their comprehensive plans. The majority of jurisdictions fail to integrate drought mitigation and adaptation strategies into their land use planning. By understanding their strengths and weaknesses, policy implications and recommendations are given.

Effectiveness of Drought Mitigation Strategies in Bikita District, Zimbabwe

Drought induced famine has been the worst disaster from which most rural people experience immense anguish. It still remains a National Policy agenda and a problem in most developing countries like Zimbabwe. Due to climate change, the impacts of droughts are expected to deepen where the capacity to adapt is low. Though it remains a challenge in communities, local people have devised different coping mechanisms based on the resources that are locally available but the effectiveness of these mechanisms are questionable. Therefore, using both qualitative and quantitative research methods this paper aims at identifying the drought mitigation strategies used in the Ward 2 of Bikita District, assess the impacts of these strategies and examine the challenges faced during attempts to implement them. Results indicated that in Ward 2 of Bikita District, people are using drought mitigation strategies which include food aid, food for work, and sale of livestock, remittances and irrigation scheme. It was also revealed that the most effective drought mitigation strategies were provision of food aid and food for work whereas the least effective were remittances and irrigation. The study also revealed that 72% of the community was not satisfied with the effectiveness of all the drought mitigation strategies being used. These strategies are held back by challenges in the Ward which include poor service delivery by NGOs and Government departments in mitigating droughts, poverty, corruption, lack of resources and unclear selection criterion of beneficiaries as well as lack of markets thereby leading to inefficiency of the drought mitigation strategies. The study recommended the construction of more dams and necessary infrastructure for irrigation, adoption of local knowledge into mitigation strategies, improving access to agricultural inputs and enhanced provision of technical assistance to farmers in the area.

Drought impact on crop production and the soil environment: 2012 experiences from Iowa

Enormous challenges were presented by the 2012 drought. Poor water availability and high temperatures resulted in significant stress during critical phases of corn (Zea mays L.) and soybean (Glycine max L.) development. These stress factors lead to management challenges with insects, diseases, and reduced nutrient availability and uptake by plants. The drought triggered soil changes, particularly in conventional tillage systems, such as increased fracturing, crusting, and deterioration of soil structure and aggregation. All this reinforced the need for soil conservation planning, especially its necessary role in buffering against unpredictable conditions and the impacts of dry and wet events on production and soil quality. In 2011, the USDA's National Drought Mitigation Center reported that 43% of Iowa experienced moderate-drought conditions and nearly 10% experienced severe-drought conditions. In 2012, 100% of Iowa experienced severe-drought conditions, while 65% experienced extreme-drought conditions by October. This article addresses several effects of drought on soil and crop production and lessons learned that will help develop appropriate drought mitigation strategies for future soil and crop management practices.

Evaluation of SEBS for estimation of actual evapotranspiration using ASTER satellite data for irrigation areas of Australia

Spatial knowledge of land surface evapotranspiration (ET) is of prime interest for environmental applications, such as optimizing irrigation water use, irrigation system performance, crop water deficit, drought mitigation strategies, and accurate initialization of climate prediction models especially in arid and semiarid catchments where water shortage is a critical problem. The recent drought in Australia and concerns about climate change have highlighted the need to manage water resources more sustainably especially in the Murrumbidgee catchment which utilizes bulk water for food production. This study deals with the application of a Surface Energy Balance System (SEBS) algorithm based on Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) data and field observations has been proposed and tested for deriving ET over Coleambally Irrigation Area, located in the southwest of NSW, Australia. We have used 12 ASTER scenes covering the time period of 2002, 2003, 2004, 2005, 2006, and 2009 for estimating the actual ET over the study area. To validate the proposed methodology, the ground-measured ET was compared to the ASTER-derived actual ET values for the study area. The derived ET value over the study area is much closer to the field measurement. From the remote sensing results and observations, the root mean square error is 0.89 and the mean absolute percentage difference is 2.87 %, which demonstrate the reasonability of SEBS ET estimation for the study area.

Retrieved actual ET using SEBS model from Landsat-5 TM data for irrigation area of Australia

The idea of ground-based evapotranspiration (ET) is of the most interesting for land–atmosphere interactions, such as water-saving irrigation, the performance of irrigation systems, crop water deficit, drought mitigation strategies and accurate initialization of climate prediction models especially in arid and semiarid catchments where water shortage is a critical problem. The recent year's drought in Australia and concerns about climate change has prominent the need to manage water resources more sustainably especially in the Murrumbidgee catchment which utilizes bulk water for food security and production.This paper discusses the application of a Surface Energy Balance System (SEBS) model based on Landsat-5 TM data and field observations has been used and tested for deriving ET over Coleambally Irrigation Area (CIA), located in the southwest of NSW, Australia. 16 Landsat-5 TM scenes were selected covering the time period of 2009, 2010 and 2011 for estimating the actual ET in CIA. To do the validation the used methodology, the ground-measured ET was compared to the Landsat-5 TM retrieved actual ET results for CIA. The derived ET value over CIA is much closer to the field measurement. From the remote sensing results and observations, the root mean square error (RMSE) is 0.74 and the mean APD is 7.5%. The derived satellite remote sensing values belong to reasonable range.

Innovative Sustainable Drought Management Strategy Incorporating Forensic Techniques and Policy Framework

The ever-growing human population and the changing food habits of the expanding middle class in emerging economies with more and more advanced technological needs, along with foreseeable changes in climate (global warming) due to intensified human activity may exacerbate the occurrence and magnitude of droughts all over the world. Both this generation and future generations are left vulnerable to droughts that could have serious global consequences. Droughts are already an integral part of global climate variability, but their impact can be mitigated significantly by proactive risk management planning and preparedness emphasizing increase in water supplies with appropriate reduction in demands, strengthening regulatory framework, education, emergency responses and community rehabilitation services. Sustainable mitigation initiatives are needed to protect life and manage risks and damages to property, agriculture, industries, ecological biodiversity and natural resources. Forensic applications can help in many ways, for example, to understand interaction between components of hydrologic cycle, to determine their origin and history, in land use classification, to locate recharge areas, and in the management of water quality, as well as to determine the time of release, to identify the sources of pollution and dominant ongoing biochemical reactions, to resolve disputes, and to synthesize missing historic data that are so critical in the planning for worst droughts. Weather forecasting capabilities can reduce uncertainties and help in drought preparedness and mitigation strategies. This article reviews global weather pattern and interactions as well as coupled ocean-land-atmosphere phenomenon (El Niño Southern Oscillation and/or La Niña [ENSO] ENSO) causing interannual global climate variability, drought preparedness planning and policies, and mitigation strategies to conserve water, enhance water use efficiencies, to promote sustainable socioeconomic development, and to preserve values of natural resources. Potential applications of classic and emerging forensic fingerprinting techniques and materials to enhance and harness diverse sources of water and address growing water needs now and in the future are also discussed. Finally, an innovative sustainable drought management strategy is proposed.

Drought Assessment and Forecasting: A Case Study on the Yarra River Catchment in Victoria, Australia

Drought is a natural phenomenon, and has widespread and significant impacts on the world’s economy, environment, industries and the wider community. Early detection of droughts helps to implement drought mitigation strategies and measures before they occur. Therefore, drought forecasting plays an important role in the planning and management of water resources systems, especially during dry climatic periods. However, drought assessment and forecasting are not always easy tasks. In this paper, an approach that was developed and tested for drought assessment and forecasting is presented together with a case study on the Yarra River catchment in Victoria (Australia). An evaluation of existing drought indices was first conducted in this study, which led to the development of a new non-linear aggregated drought index (NADI). The NADI defines a broad perspective of dryness within the catchment rather than the traditional individual meteorological, hydrological and agricultural subcategories. Thereafter, a novel drought forecasting modelling approach was developed using the NADI time series. The results show that the developed forecasting models are capable of forecasting drought conditions well up to 6 months ahead forecasts which were statistically significant at 1% level. The outcomes of this study will be useful for water resources managers to assess droughts effectively and forecast future drought conditions, which will allow them to plan ahead the future water management activities especially during drought periods.

On the forest cover–water yield debate: from demand‐ to supply‐side thinking

Several major articles from the past decade and beyond conclude the impact of reforestation or afforestation on water yield is negative: additional forest cover will reduce and removing forests will raise downstream water availability. A second group of authors argue the opposite: planting additional forests should raise downstream water availability and intensify the hydrologic cycle. Obtaining supporting evidence for this second group of authors has been more difficult due to the larger scales at which the positive effects of forests on the water cycle may be seen. We argue that forest cover is inextricably linked to precipitation. Forest-driven evapotranspiration removed from a particular catchment contributes to the availability of atmospheric moisture vapor and its cross-continental transport, raising the likelihood of precipitation events and increasing water yield, in particular in continental interiors more distant from oceans. Seasonal relationships heighten the importance of this phenomenon. We review the arguments from different scales and perspectives. This clarifies the generally beneficial relationship between forest cover and the intensity of the hydrologic cycle. While evidence supports both sides of the argument – trees can reduce runoff at the small catchment scale – at larger scales, trees are more clearly linked to increased precipitation and water availability. Progressive deforestation, land conversion from forest to agriculture and urbanization have potentially negative consequences for global precipitation, prompting us to think of forest ecosystems as global public goods. Policy-making attempts to measure product water footprints, estimate the value of ecosystem services, promote afforestation, develop drought mitigation strategies and otherwise manage land use must consider the linkage of forests to the supply of precipitation.

Application of copulas for derivation of drought severity–duration–frequency curves

AbstractThis study presents copula‐based multivariate probabilistic approach to model severity–duration–frequency (S‐D‐F) relationship of drought events in western Rajasthan, India. Drought occurrences are analysed using standardized precipitation index computed on monthly mean areal precipitation, aggregated at a time scale of 6 months. After testing with a series of probability density functions, the drought variable severity is found to be better represented with log‐normal distribution, whereas duration is well fitted with exponential distribution. Four different classes of bivariate copulas – Archimedean, extreme value, Plackett, and elliptical families are evaluated for modelling joint distribution of drought characteristics. It is observed that the extreme value copula – Gumbel–Hougaard copula – performed better as compared with other classes of copulas, based on results of various statistical tests and upper tail dependence coefficient. The joint distribution obtained from best performing copula is then employed to determine conditional return period and to derive drought severity‐duration‐frequency (S‐D‐F) curves for the study region. The results of the study suggests that the copula method can be used effectively to derive the drought S‐D‐F curves, which can be helpful in planning and adopting suitable drought mitigation strategies in drought‐prone areas. Copyright © 2011 John Wiley & Sons, Ltd.

Economics of Drought in India

This research 'Economics of drought in India' is aimed at taking an overview of the drought in India during 1991-2003. The scope was limited to cover the impacts of drought on agriculture and livestock in the State of Orissa during 1991-2003. The desktop methodology was employed to undertake this research for which secondary data was used. The results show that 2002-2003 drought in Orissa effected agriculture by damaging crop production of 85 million tons. However, it was the livestock which was hit severely by the 1999-2003 droughts. The impact of drought on livestock indicates that 92 million cattle population was affected. The total economic loss to agriculture and livestock was estimated as US$ 31370 million (US$ 510 million loss to agriculture and US$ 30860 million to livestock subsectors). There were also some benefits accrued from this drought in the form of increase in number of tube wells, adoption of efficient irrigation technologies etc. However, monetary value of such benefits was difficult to estimate and may need separate research in future. The research proposes a number of recommendations for mitigation of drought such as Preventive measures by public sectors, preparation of drought mitigation strategies, institutional infrastructure, capacity building and timely emergency relief as a quick response to address immediate concerns (food grains, fodder and medicine for livestock, seed and fertilizers). The long term strategies suggested in this research include developing database, effective monitoring system, and financial, engineering, agronomical and social interventions to minimize the impacts of future droughts.

Value of Irrigation Water for Drought Proofing in the South Saskatchewan River Basin (Alberta)

Typically, the value of irrigation water is recognized for enhancing producer income and reducing rural poverty through its primary use—crop production. However, in this study an additional benefit to producers from irrigation is explored—reducing variability in farm income due to extreme weather events (droughts). This benefit is estimated for the Alberta portion of the South Saskatchewan River Basin (SSRB). Benefits from irrigation during a drought year were measured as the difference between producer surpluses from irrigated and dryland production systems, in a drought year, excluding the value of water for irrigated crop production in a non-drought year. This value was expressed per unit of water applied to irrigation. Short-run value estimates ranged from $37 per dam3 in the Bow River sub-basin, to about $42 per dam3 in the Oldman River sub-basin. These results suggest that water used for irrigation provides additional benefits beyond enhanced producer income in crop production. Thus, it is an effective drought mitigation strategy, and provides a successful adaptation to occurrence of extreme events (droughts) under climate change.

New U.S. drought web site

A new U.S. Drought Portal Web site will help provide early warnings about droughts, offer information about risk and impact of droughts to different agencies and stakeholders, and explain how to plan for and manage the impacts of droughts. The portal (http://www.drought.gov), unveiled by the National Oceanic and Atmospheric Administration (NOAA) on 1 November, was developed as part of the National Integrated Drought Information System (NIDIS). The NIDIS implementation plan also calls for integrating and fostering drought mitigation strategies through research, preparedness, education, and public awareness as well as developing pilot programs for the design and implementation of early warning systems in selected locations. The portal “centralizes drought information in an unprecedented manner, and paves the way for planned early warning system development pilots in select watersheds and states across the U.S.,” said Roger Pulwarty, director of the NIDIS program office located on NOAA's campus in Boulder, Colo.

Evaluating the Impact of Drought Using Remote Sensing in a Mediterranean, Semi-arid Region

This paper analyses monthly differences in drought impact on vegetation activity in a semi-arid region in the north-east of the Iberian Peninsula between 1987 and 2000. The study determines spatial differences in the effects of drought on the natural vegetation and agricultural crops by means of the joint use of vegetation indexes derived from AVHRR images, a drought index (standardized precipitation index), and Geographic Information Systems. The results show that the effect of drought on vegetation varies noticeably between areas, a pattern that is determined mainly by the location of land-cover types. The influence also varies each month and, in general, is higher during the spring and summer. Aridity and vegetation characteristics similarly account, in part, for spatial differences in the impact of drought on vegetation. In general, the most arid areas, where vegetation cover and activity are low, are those in which the interannual variability of vegetation activity is more determined by the drought occurrence. In assessing drought impact, this analysis takes into account the effects of drought on the vegetation and also considers spatial and seasonal differences. The results should be useful for the management of natural vegetation and crops and for the development of better drought mitigation strategies.

Managing agricultural intensification: The role of international research

Over the next 20–25 yr, global food demand is expected to increase by around 50%, largely due to demand in developing countries. The challenge is to increase production without damaging the natural resource base. Various technologies for integrated natural resource management (INRM) have been developed, but adoption has been poor, for various reasons—technical, socio-economic, and institutional. To date a great deal of past work has focused at the plot and farm level, with little farmer involvement in developing the research agenda. Work needs to be extrapolated to more sites, with greater farmer involvement in the research process, in order to answer the key question: ‘Under what conditions will rural households be encouraged to reinvest in their agroecosystems?’ Encouraging such investment involves several challenges: improving returns from such investments; creating market access for smallholder farmers; improving research–extension–farmer linkages; developing enabling policies on soil, water and biodiversity; integration of livestock–wildlife–crop systems; development of drought mitigation strategies; capacity building; better information flow; and a clearer gender perspective in research and training. A large body of successful INRM research is available from many countries in the West and in Latin America. Unfortunately much of this work is reaching sub-Saharan Africa only now, and its appropriateness to the needs of the African smallholder farmer requires verification. This paper shares some of the experiences of the Consultative Group on International Agricultural Research (CGIAR), International Agricultural Research Centers (IARCs) in Africa, particularly the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). Reference is made to some specific technologies and some limited successes with small-scale farmers in Africa.