Drought Risk Mitigation Research Articles

Drought risk assessment for citrus and its mitigation resistance under climate change and crop specialization: A case study of southern Jiangxi, China

Crop specialization has become an important way to promote agricultural efficiency and increase incomes for farmers in China. Under extreme weather conditions, this is likely to increase resistance to drought risk mitigation and lead to greater drought damage. In order to make more sophisticated mitigation policy decisions, it requires efforts to assess crop drought risk variability and its risk mitigation resistance in detail. This study focuses on citrus as a cash crop, using a case of southern Jiangxi. We first constructed a drought risk assessment system for citrus, and then geographic information technology was used to characterize the risk dynamics. The factor contribution model was applied to calculate the risk mitigation resistance. And the least square error (LSE) model was finally employed to classify risk mitigation resistance types. The results showed that citrus drought risk had fluctuated moderately over macro-regions in the past 30 years, but had varied dramatically at local scales. Citrus drought risk significantly increases during the bud bust to flowering, fruit expansion, and fruit maturation stages. Exposure contributed 33.23 % to drought risk fluctuations, specifically, mainly attributed to the amplification of drought exposure in the farmer and agricultural production sectors, while 14.95 % was derived from climate change. In large-scale citrus expansion areas, the improvement in drought mitigation capacity generally lags behind the increase rate of the exposure system. The LSE model showed that risk mitigation resistance type varied across regions at system level and indicator level. In addition, water scarcity has emerged as a widespread issue that limits drought risk mitigation. Generally, this study provides new insights into the measurement of drought risk mitigation resistance and its type identification, thus contributing to the safe supply of agricultural products and human well-being.

Drought risk assessment on arid region under different socioeconomic scenarios: A case of Loess Plateau, China

Quantitative understanding of drought risks on arid region is vital in drought risk mitigation and ecological restoration. However, no study has been conducted on the drought risk variance between different shared socioeconomic pathway (SSP) scenarios and China’s dual carbon goals scenario on arid region. This study evaluates drought risks of Loess Plateau between the year of 1980–2100 based on the Coupled Model Intercomparison Project phase 6 data sets and the United Nations International Strategy for Disaster Reduction drought risk assessment framework. The average values of the drought risk index in four scenarios during the projection period (2030–2100) are 0.29 (±0.026) for the low carbon emission scenario, 0.257 (±0.019) for the China’s dual carbon target scenario, 0.232 (±0.057) for the medium carbon emission scenario, and 0.248 (±0.059) for the high carbon emission scenario, which are higher than the historical period (i.e. 1980: 0.210; 2020: 0.215). Accordingly, the Loess Plateau will have severe drought risks in the future. In the zone of increased drought risk indices on the Loess Plateau, the areas of woodland and croplands increased, whereas the area of grasslands increased in the zone of decreased drought risk indices. China’s dual carbon goals (i.e. SSP1-2.6) scenario has the smallest degree of variability in drought risk, which is the most reliable pathway of across the four scenarios. We emphasize the potential of spatial planning based on regional characteristics and creating ecological buffer zones for endemic biome habitats to address the uncertainty of drought risk in arid and semi-arid regions like the Loess Plateau.

The Three-Points Sponge Policy approach; toward an enhanced multi-level resilience strategy

Urban water management is confronted with more frequent, more extreme weather events. This paper introduces the Three-Points Approach (3PA) into Sponge City concept, to create a novel framework aimed at guiding water management interventions across local, urban, regional, and river basin scales. The 3PA integrates three domains—Day-to-day, Design, and Extreme —offering a nuanced strategy for flood and drought risk mitigation, also for extreme events. Notably, the 3PA emphasizes the fusion of blue-green infrastructure (BGI) with conventional gray approaches to enhance both multifunctionality and resilience in extreme weather conditions. The study identifies critical issues of implementing this Three-Points Sponge Policy (3PSP) approach, including spatial and temporal scales, transitioning from gray to blue-green infrastructure, asset management, data handling, and effective communication. Interventions spanning various spatial scales and addressing flood protection, drought resilience, and water quality are explored in a first and indicative application in Zhengzhou. The case study distills key design principles, highlighting the imperative of never shifting problems, embracing ecosystem-based adaptation, seeking synergy between interventions, and incorporating adaptability into designs. The 3PSP approach emerges as a holistic framework that considers both risks and benefits, contributing valuable insights to the discourse on integrating urban and river basin water management, improving our ways of dealing with extreme weather events while maximizing the day-to-day benefits of our interventions.

Drought Characterization and Potential of Nature-Based Solutions for Drought Risk Mitigation in Eastern Ethiopia

Drought is one of the challenges in Ethiopia that affects the agricultural production. Ecosystems can mitigate the effects of climate-related hazards including drought. For this reason, nature-based solutions (NbS) are becoming more prominent to manage climate-related impacts in developing countries; however, there is still limited empirical evidence, which would inform NbS policy and practices. Thus, the aim of this study was to characterize droughts in Eastern Ethiopia (the case of Erer Sub-basin) and assess the effectiveness of various NbS for drought. The temporal changes in soil moisture deficit index (SMDI) (agricultural drought) and standard precipitation evapotranspiration index (SPEI) (meteorological drought) at various timescales (1, 3, and 6 months) between 1981 and 2020 were analyzed. Qualitative analysis was used to categorize and evaluate the effectiveness of NbS to mitigate drought risk by adopting a Living Labs approach. Overall, the study revealed that droughts showed an increasing trend with more frequency, longevity, and severity. The drought analysis results showed that SPEI’s variants were less reliable than SMDI0–5 and SMDI5–100. With an increase in rainfall, SPEI showed stronger relationships with SMDI0–5 at one and two-month delays between May and July. SPEI and SMDI5–100 performed better in terms of capturing actual drought occurrences than SMDI0–5. The results of focus group discussions (FGD) suggested NbS such as habitat restoration, structural restoration, reforestation, rehabilitation, revegetation, land enclosures, conservancies, and locally managed areas have been practiced as a strategy to manage drought risks. Overall, the study indicated that a new, comprehensive approach through nature-based solutions to reduce the risk of drought is urgently needed.

Observed and projected changes in wet and dry spells for the major river basins in East Asia

AbstractSpatiotemporal changes in wet and dry spells had significantly contributed to climate‐related natural hazards in East Asia, especially in river basins undergoing warming. However, few studies have systematically analysed these changes for river basins at different latitudes. Herein, we investigated the observed and projected variations in wet and dry spells for East Asian river basins at different latitudes. We found that river basins at low latitudes (Yangtze and Pearl rivers) had obvious wet characteristics, whereas those at high latitudes (Amur and Yellow rivers) had obvious dry characteristics. In general, the river basins presented a ‘wet south but dry north’ spatial pattern. Long‐duration wet spells have been shown to be the primary contributor to total wet spells in low‐latitude river basins, while long‐duration dry spells have been found to be the primary contributor to total dry spells in high‐latitude river basins. Importantly, climate is changing from prolonged wet spells to short, intense wet spells in low‐latitude river basins, whereas the climate is changing from single, short dry spells to moderate, prolonged dry spells at high latitudes. These changes indicate a high probability of flash floods in river basins at low latitudes and a high probability of droughts at high latitudes. In the future, more temporally clustered heavy precipitation events and prolonged dry spells may lead to increasingly uneven precipitation in high‐latitude river basins and the Pearl River basin, especially under the higher shared socioeconomic pathway scenarios. In contrast, more frequent consecutive heavy precipitation events may aggravate the risk of flooding in the Yangtze River basin. These findings are expected to serve as a guide for flood and drought risk mitigation in East Asia under a warming climate.

Plant diversity and ecological intensification in crop production systems

AbstractEcological intensification (EI) is the enhancement of ecosystem services to complement or substitute for the role of anthropogenic inputs in maintaining or increasing yields. EI has potential to increase farming’s environmental sustainability, e.g. reducing environmentally harmful management activities while sustaining yields. EI is based upon ecological processes which in turn are influenced by biodiversity. We review how biodiversity, particularly vascular plant diversity, can regulate ecosystem processes relevant to EI at multiple spatial scales. At an individual plant genotype level, complementarity in functional traits has a direct impact on productivity. At in-field, population level, mixtures of crop types confer resilience to minimize the risk of pest and disease incidence and spread. Scaling up to the field level, a diversity of non-crop plants (i.e. weeds) provides resources necessary for in-field functional processes, both below ground (carbon inputs, decomposition) and above ground (resource continuity for pollinators and natural enemies). At the landscape scale, mosaics of semi-natural and managed vegetation provide buffers against extreme events through flood and drought risk mitigation, climate amelioration and pest population regulation. Overall this emphasizes the importance of heterogeneity across scales in maintaining ecosystem functions in farmland. Major research challenges highlighted by our review include the need: to better integrate plant functional diversity (from traits to habitat scales) into cropping system design; to quantify the (likely interactive) contribution of plant diversity for effective EI relative to other management options; and to optimize through targeted management the system function benefits of biodiversity for resilient, efficient and productive agroecosystems.

Rainwater Harvesting and Treatment: State of the Art and Perspectives

Rainwater harvesting is an ancient practice currently used for flood and drought risk mitigation. It is a well-known solution with different levels of advanced technology associated with it. This study is aimed at reviewing the state of the art with regards to rainwater harvesting, treatment, and management. It focuses on the environmental and social benefits of rainwater harvesting and links them to the Sustainable Development Goals. The review identifies characteristics of laws and regulations that encourage this practice and their current limitations. It presents methodologies to design a rainwater harvesting system, describes the influence of design variables, and the impact of temporal and spatial scales on the system’s performance. The manuscript also analyzes the most advanced technologies for rainwater treatment, providing insights into various processes by discussing diverse physiochemical and biological technology options that are in the early stages of development. Finally, it introduces trends and perspectives which serve to increase rainwater harvesting, water reuse, and effective management.

Dynamic evolution of recent droughts in Central Asia based on microwave remote sensing satellite products

Under warm climates, the more complex and malleable relationship between water and heat and the changes in the water components at the land–atmosphere interface pose greater challenges to understanding hydro-meteorological processes. However, the emergence of the advanced microwave scanning radiometer (AMSR) has facilitated the precise monitoring of these changes. Therefore, this study investigated and analyzed the spatiotemporal transformation characteristics of drought–wetness and its driving mechanisms in Central Asia from July 2002 to December 2018 based on the AMSR surface wetness index (ASWI) coupled with multiple water components. Three major conclusions were drawn from this investigation. First, the spatiotemporal differences in multiple water components in Central Asia caused substantial spatiotemporal differences in the extent of changes in drought–wetness. For example, arid areas were mainly concentrated in the lower reaches of the Amu Darya and Syr Darya river basins, where the dominant drought periods were 2007 and 2018. Second, the centroids of the largest drought patches were mainly located in the northeast, northwest, and southwest regions of Central Asia. Central Asia experienced a continuous drought from 2002 to 2005, and then a gradual wetting from 2008 to 2017. Third, the drought–wetness variation can be attributed to the variation of water vapor flux in the typical barometric layer as well as the variation of precipitation and temperature. The ASWI may play an essential role in drought monitoring and tracking prediction, particularly for drought risk mitigation and aversion.

Center Pivot Irrigation Systems as a Form of Drought Risk Mitigation in Humid Regions

Center Pivot Irrigation Systems as a Form of Drought Risk Mitigation in Humid Regions

Probabilistic assessment of crop yield loss to drought time‐scales in Xinjiang, China

AbstractFrequent drought events under climate change are endangering food security and sustainable agricultural development. Quantitative assessment of crop yield anomalies under drought conditions is essential for effective water resources management and adaptative drought risk mitigation strategies. In this study, a copula‐based bivariate probabilistic framework model is developed to assess the impacts of drought events on crop yield, where the correlation of crop yield anomalies and standardized precipitation evapotranspiration index (SPEI) at multi‐month lags are quantified. This model has advantages in quantifying the impacts of drought scales on crop yield through the joint probability of the corresponding series. Then, the model is applied to Xinjiang Province in Northwestern China, an arid region with extensive agricultural activities. SPEI and yield anomalies of wheat, maize and cotton during 1984–2015 are firstly identified, and then copula‐based framework is constructed to quantify probabilistic crop yield losses caused by drought events. Finally, crop water amounts and irrigation requirements under different drought severity conditions are compared and analysed. Our findings are: (a) wheat and maize yield anomalies are vulnerable to long drought time‐scales, with exceedance probabilities of required yield anomalies returning to normal are 19.3% for wheat and 21.1% for maize, while cotton is susceptible to short drought time‐scales, with exceedance probability of 42.3% for drought recovery; (b) response of wheat crop yield anomalies to the SPEI at 1‐, 3‐, 6‐ and 12‐month scales is the most sensitive, followed by maize, and cotton is the least; (c) under extreme drought conditions, the probability of cotton yield reduction is lower than that of wheat and maize. Results may enhance our understanding of the impacts of drought scales on crops during the growing season, thus providing general guidance for rational irrigation management of crops and incentives for irrigation to mitigate drought risk, ultimately promoting sustainable agricultural development.

Future drought characteristics through a multi-model ensemble from CMIP6 over South Asia

To characterize future drought events over a drought prone area like South Asia is paramount for drought risk mitigation. In this paper, a five-model ensemble mean from CMIP6 was chosen to project drought characteristics in South Asia under the latest SSPs-RCPs emission scenarios (SSP1–2.6, SSP2–4.5, and SSP5–8.5) for the period 2020–2099. Additionally, corresponding scenarios RCP2.6, RCP4.5 and RCP8.5 of CMIP5 were used for comparison and to identify the changes and improvements of CMIP6 over the South Asia. Principle Component Analysis and the Varimax rotation method is used to divided the study area into five homogenous drought sub-regions. Drought duration, frequency, and intensity are analyzed based on the Run theory, and the Standardized Precipitation Evapotranspiration Index (SPEI) at 12-months timescale, and the self-calibrating Palmer Drought Severity Index (sc-PDSI). The Modified Mann-Kendall and Sen's slope method is adopted to detect sub-regional trends in drought characteristics. Results show that significant increases in drought conditions mainly pronounced over the North-West sub-region. Strong increases are projected in the average drought duration and drought frequency. The North-West sub-region is the most vulnerable to face frequent drought events with longer duration with higher intensity. Parts of the South-West, North-Central, and North-East sub-regions will also face more adverse drought conditions in future. The selected model ensemble from CMIP6 has a very robust capability to simulate present climate parameters (precipitation, temperature, and evaporation) and satisfactorily captures drought characteristics in South Asia. These results provide a basis for developing drought adaptation measures for South Asia.

Less to Lose? Drought Impact and Vulnerability Assessment in Disadvantaged Regions

Droughts hit the most vulnerable people the hardest. When this happens, everybody in the economy loses over the medium- to long-term. Proactive policies and planning based on vulnerability and risk assessments can reduce drought risk before the worst impacts occur. The aim of this article is to inform a global initiative, led by the United Nations Convention to Combat Desertification (UNCCD), to mitigate the effects of drought on vulnerable ecosystems and communities. This is approached through a rapid review of experiences from selected nations and of the available literature documenting methodological approaches to assess drought impacts and vulnerability at the local level. The review finds that members of the most vulnerable communities can integrate available methods to assess drought risks to their land and ecosystem productivity, their livelihoods and their life-supporting hydrological systems. This integration of approaches helps to ensure inclusive assessments across communities and ecosystems. However, global economic assessments often still fail to connect to holistic consideration of vulnerability at a local scale. As a result, they routinely fall short of capturing the systemic effects of land and water management decisions that deepen vulnerability to droughts over time. To ensure proactive and inclusive drought risk mitigation, multiscale, systemic approaches to drought vulnerability and risk assessment can be further reinforced at a global level.

Mapping the Spatial-Temporal Dynamics of Vegetation Response Lag to Drought in a Semi-Arid Region

Drought, as an extreme climate event, affects the ecological environment for vegetation and agricultural production. Studies of the vegetative response to drought are paramount to providing scientific information for drought risk mitigation. In this paper, the spatial-temporal pattern of drought and the response lag of vegetation in Nebraska were analyzed from 2000 to 2015. Based on the long-term Daymet data set, the standard precipitation index (SPI) was computed to identify precipitation anomalies, and the Gaussian function was applied to obtain temperature anomalies. Vegetation anomaly was identified by dynamic time warping technique using a remote sensing Normalized Difference Vegetation Index (NDVI) time series. Finally, multilayer correlation analysis was applied to obtain the response lag of different vegetation types. The results show that Nebraska suffered severe drought events in 2002 and 2012. The response lag of vegetation to drought typically ranged from 30 to 45 days varying for different vegetation types and human activities (water use and management). Grasslands had the shortest response lag (~35 days), while forests had the longest lag period (~48 days). For specific crop types, the response lag of winter wheat varied among different regions of Nebraska (35–45 days), while soybeans, corn and alfalfa had similar response lag times of approximately 40 days.

Does Wetland Location Matter When Managing Wetlands for Watershed‐Scale Flood and Drought Resilience?

AbstractWetland protection and restoration strategies that are designed to promote hydrologic resilience do not incorporate the location of wetlands relative to the main stream network. This is primarily attributed to the lack of knowledge on the effects of wetland location on wetland hydrologic function (e.g., flood and drought mitigation). Here, we combined a watershed‐scale, surface–subsurface, fully distributed, physically based hydrologic model with historical, existing, and lost (drained) wetland maps in the Nose Creek watershed in the Prairie Pothole Region of North America to (1) estimate the hydrologic functions of lost wetlands and (2) estimate the hydrologic functions of wetlands located at different distances from the main stream network. Modeling results showed wetland loss altered streamflow, decreasing baseflow and increasing stream peakflow during the period of the precipitation events that led to major flooding in the watershed and downstream cities. In addition, we found that wetlands closer to the main stream network played a disproportionately important role in attenuating peakflow, while wetland location was not important for regulating baseflow. The findings of this study provide information for watershed managers that can help to prioritize wetland restoration efforts for flood or drought risk mitigation.

Analysis of drought and vulnerability in the North Darfur region of Sudan

AbstractNorth Darfur of Sudan is located on the edge of the Sahara Desert and endures frequent droughts due to water shortages and high summer temperatures. Monitoring and understanding drought characteristics are essential for integrated drought risk mitigation and prevetion of land degradation. This study evaluates drought conditions in North Darfur by analyzing the spatiotemporal distribution of drought using three drought indices (Standardized Precipitation Index, Vegetation Condition Index, and Soil Moisture Content Index) and their combined drought index (CDI) from 2004 to 2013. Biophysical and socioeconomic indicators are further used to measure vulnerability to drought risk and its three components (exposure, sensitivity, and adaptive capacity) through a comprehensive risk assessment framework. The results show that most of North Darfur has experienced prolonged droughts during the study period, especially from 2007 to 2011. There is also a significant correlation between the monsoon season CDI and annual crop yield anomaly. The results confirm the validity of the CDI index, which provides a comprehensive description of the drought situation by combing four drought indices quantifying different drought aspects. The vulnerability results show that the majority of this region is highly exposed and sensitive to drought risks. In particular, the northern zone of the region is highly vulnerable, which is categorized by less‐crop diversity, higher land degradation, frequent droughts, and high‐poverty levels. This study provides valuable information for coping with climate change‐induced drought risk in this region and demonstrates that there is still a large room for enhancing the adaptation capacity in this region.

Space-time characterization of drought events and their impacts on vegetation in Central Asia

Understanding the space-time structure and characteristics of drought is crucial for drought risk mitigation and forecasting efforts. In this paper, the drought events are identified by an improved 3-dimensional clustering algorithm. The 3-month Standardized Precipitation Evapotranspiration Index (SPEI3) is calculated based on the Climatic Research Unit (CRU) dataset from January 1966 to December 2015 to construct the longitude-latitude-time space. The characteristics of these identified events are described by a series of indicators such as duration, severity, intensity, affected area, centroids and track path after which the spatial pattern and temporal evolution are studied. In addition, the Vegetation Health Index (VHI), Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) are also included to investigate the possible impact of drought on the vegetation health. Results show that a total of 60 persisting drought events for at least 3 months have been identified in Central Asia. The most severe drought event occurred between May 1974 and January 1976 with a duration of 21 months and an affected area of 5.77 million km2. Most events have a duration between 3 and 5 months. In addition, the droughts in Central Asia tend to have an east-west trajectory. Seasonally, the study area experienced more drought months in spring and summer. During the recent 35 years, there has been a slowly increasing thermal stress and a significantly decreasing soil moisture stress that causes an overall decreasing drought stress on vegetation health.

An EPIC model-based wheat drought risk assessment using new climate scenarios in China

There is considerable research interest in future agro-drought risk assessment, since the increasing severity of climate change-related hazards poses a great threat to global food security. Wheat is the most important staple crop in the world, and China’s wheat production has long been impacted by drought. The frequency, intensity, and duration of droughts may increase due to climate change and stressing the need for robust assessment methods for drought risk, as well as adaptation and mitigation strategies. This paper investigates a method for assessing future wheat drought risk using climate scenarios and a crop model. We illustrate the utility of such an approach by assessing the risk of wheat drought under climate change scenarios in China using the Environmental Policy Integrated Climate model. Results show that the risk level of wheat drought is highest under scenario RCP8.5, followed by RCP4.5, RCP6.0, and RCP2.6, in descending order. If current climate change trends continue, wheat drought risk in China will be at risk levels between RCP6.0 and RCP8.5 by the end of the twenty-first century. The wheat drought risk assessment shows a “low-risk, high-risk, low-risk” spatial pattern starting in the spring wheat-planting regions in northern China and progressing to the winter wheat-planting regions in southern China. Significant differences were observed across regions, but in all RCP scenarios, the relative high-risk zones are the Huang-Huai Winter Wheat Region and the North Winter Wheat Region. In addition, wheat drought risk mitigation and adaptation strategies in China are proposed.

Spatial and temporal characteristics of droughts in Central Asia during 1966–2015

In drought-prone regions like Central Asia, drought monitoring studies are paramount to provide valuable information for drought risk mitigation. In this paper, the spatiotemporal drought characteristics in Central Asia are analyzed from 1966 to 2015 using the Climatic Research Unit (CRU) dataset. Drought events, as well as their frequency, duration, severity, intensity and preferred season, are studied by using the Run theory and the Standardized Precipitation Evapotranspiration Index (SPEI) at 3-month, 6-month, and 12-month timescales. The Principle Components Analysis (PCA) and the Varimax rotation method, the Sen's slope and the Modified Mann-Kendall method (MMK), as well as the wavelet analysis are adopted to identify the sub-regional drought patterns and to study the drought trend, periodicity and the possible links between drought variation and large-scale climate patterns, respectively. Results show that the drought characteristics in Central Asia vary considerably. The Hexi Corridor region and the southeastern part suffered from more short-term drought occurrences which mostly occurred in summer while the northeastern part experienced fewer droughts with longer duration and higher severity. Central Asia showed an overall wetting trend with a switch to drying trend since 2003. Regionally, the continuous wetting trend is found in north Kazakhstan while a consistent drying in the Aral Sea and Hexi Corridor region is observed in the last half-century. For 2003–2015, a significant drying pattern is detected in most Central Asia, except the northern Kazakhstan. A common significant 16–64-month periodical oscillation can be detected over the six sub-regions. The drought changes in Central Asia are highly associated with ENSO but less related to the Tibetan Plateau pressure. The North Atlantic Oscillation has an influence on drought change in most Central Asia but less for the Hexi Corridor and the drought variation in eastern Central Asia is affected by the strength of the Siberian High.

Water Markets and Storage — Substitutes or Complements for Drought Risk Mitigation?

Are water storage and water markets complements or substitutes? This paper examines the conditions under which water storage for drought risk mitigation augments or attenuates water market gains from trade, and conversely, the conditions under which water markets augment or attenuate the value of additional water storage. The analysis is performed in the context of the Prior Appropriations doctrine in a fully appropriated basin. Two stylized examples based on water use at the intensive and extensive margin are provided, along with simulation results for proposed water storage projects and market development in the Yakima Basin in South-central Washington State.

관개취약성 평가모형 및 군집분석을 활용한 용수공급 위험도 평가

Because reservoirs that supply irrigation water play an important role in water resource management, it is necessary to evaluate the vulnerability of this particular water supply resource. The purpose of this study is to provide water supply risk maps of agricultural reservoirs in South Korea using irrigation vulnerability model and cluster analysis. To quantify water supply risk, irrigation vulnerability indices are estimated to evaluate the performance of the water supply on the agricultural reservoir system using a probability theory and reliability analysis. First, the irrigation vulnerability probabilities of 1,346 reservoirs managed by Korea Rural Community Corporation (KRC) were analyzed using meteorological data on 54 meteorological stations over the past 30 years (1981-2010). Second, using the K-mean method of non-hierarchical cluster analysis and pre-simulation approach, cluster analysis was applied to classify into three groups for characterizing irrigation vulnerability in reservoirs. The morphology index, watershed area, irrigated area, and ratio between watershed and irrigated area are selected as the clustering analysis parameters. It is suggested that the water supply risk map be utilized as a basis for the establishment of risk management measures, and could provide effective information for a reasonable decision making on drought risk mitigation.