With a risk index score of 9.9, Somalia was the country most exposed to drought risk worldwide in 2024. Namibia and Zimbabwe tied for second, with a risk index score of 9.4. That year, seven out of the 10 countries most exposed to drought hazards worldwide were located in Africa.

The country that was most at risk from drought in 2020 was Somalia, with an index score of five out of a possible five. Many of the most at risk countries were in Africa, including Zimbabwe, Djibouti, and South Africa. Drought risk is classified in terms of socioeconomic effects such as agricultural losses.

This series of datasets has been created by AAFC’s National Agroclimate Information Service (NAIS) of the Agro-Climate, Geomatics and Earth Observations (ACGEO) Division of the Science and Technology Branch. The Canadian Drought Monitor (CDM) is a composite product developed from a wide assortment of information such as the Normalized Difference Vegetation Index (NDVI), streamflow values, Palmer Drought Index, and drought indicators used by the agriculture, forest and water management sectors. Drought prone regions are analyzed based on precipitation, temperature, drought model index maps, and climate data and are interpreted by federal, provincial and academic scientists. Once a consensus is reached, a monthly map showing drought designations for Canada is digitized. AAFC’s National Agroclimate Information Service (NAIS) updates this dataset on a monthly basis, usually by the 10th of every month to correspond to the end of the previous month, and subsequent Canadian input into the larger North American Drought Monitor (NA-DM). The drought areas are classified as follows: D0 (Abnormally Dry) – represents an event that occurs once every 3-5 years; D1 (Moderate Drought) – represents an event that occurs every 5-10 years; D2 (Severe Drought) – represents an event that occurs every 10-20 years; D3 (Extreme Drought) – represents an event that occurs every 20-25 years; and D4 (Exceptional Drought) – represents an event that occurs every 50 years. Impact lines highlight areas that have been physically impacted by drought. Impact labels specify the longitude and magnitude of impacts. The impact labels are classified as follows: S – Short-Term, typically less than 6 months (e.g. agriculture, grasslands). L – Long-Term, typically more than 6 months (e.g. hydrology, ecology).

Drought occurs when a region has an imbalance between water supply and water demand over an extended period of time. Droughts can have significant environmental, economic, and social consequences. Between 1980 and the present time, the cost of drought exceeded 100 billion dollars, making drought monitoring a key factor in planning, preparedness, and mitigation efforts at all levels of government. Data Source: U.S. Drought Monitor, National Drought Mitigation Center, GISData DownloadUpdate Frequency:  Weekly, typically on Friday around 10:00AM UTC. Using the Aggregated Live Feed MethodologyFor Current Week data only: See USA Drought Intensity - Current Conditions Online Item!For Current Week data only, in USDM Symbology Style: See USA Drought Intensity - Current Conditions - USDM Color Scheme Online Item!Dataset Summary:This feature service provides access to current and historical drought intensity categories for the entire USA. These data have been produced weekly since January 4, 2000 by the U.S. Drought Monitor and the full time series is archived here. Drought intensity is classified according to the deviation of precipitation, stream flow, and soil moisture content from historically established norms, in addition to subjective observations and reported impacts from more than 350 partners across the country. New map data is released every Thursday to reflect the conditions of the previous week.Layer Summary:'US_Drought': Time series containing polygon areas by week'US_Drought_Current': Polygon areas for most recent weekTable Summary:'US_Drought_by_State': Drought Conditions Table by state by week'US_Drought_by_County':Drought Conditions Table by county by weekThe tables contain a series of drought classification summaries that fall into two groups: Categorical Percent Area and Cumulative Percent Area.

Categorical Percent Area statistic is the percent of the area in a certain drought category and excludes areas that are better or worse. For example, the D0 category is labeled as such and only shows the percent of the area experiencing abnormally dry conditions.

Cumulative Percent Area statistics combine drought categories for a comprehensive percent of area in drought. For example, the D0-D4 category shows the percent of the area that is classified as D0 or worse.Drought Classification Categories are as follows:

Class Description Possible Impacts

D0 Abnormally Dry Going into drought: short-term dryness slows growth of crops/pastures. Coming out of drought: some lingering water deficits; drops/pastures not fully recovered.

D1 Moderate Drought Some damage to crops/pastures; streams, reservoirs, or wells are low with some water shortages developing or imminent; voluntary water-use restrictions requested.

D2 Severe Drought Crop/pasture losses are likely; water shortages are common and water retrictions are imposed.

D3 Extreme Drought Major crop/pasture losses; widespread water shortages or restrictions.

D4 Exceptional Drought Exceptional and widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells creating water emergencies. The U.S. Drought Monitor is produced in partnership between the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. It is the drought map that the USDA and IRS use to define which farms have been affected by drought conditions, defining who is eligible for federal relief funds.RevisionsJul 5, 2024: Rebuilt dataset from source provider in order to correct gaps in missing or reclassified data.If you would like to be alerted to potential issues or simply see when this Service will update next, please visit our Live Feed Status Page!

Drought occurs when a region has an imbalance between water supply and water demand over an extended period of time. Droughts can have significant environmental, economic, and social consequences. Between 1980 and the present time, the cost of drought exceeded 100 billion dollars, making drought monitoring a key factor in planning, preparedness, and mitigation efforts at all levels of government. Data Source: U.S. Drought Monitor, National Drought Mitigation Center, GISData DownloadUpdate Frequency:  Weekly, typically on Friday around 10:00AM UTC. Using the Aggregated Live Feed MethodologyFor Current Week data only: See USA Drought Intensity - Current Conditions Online Item!For Current Week data only, in USDM Symbology Style: See USA Drought Intensity - Current Conditions - USDM Color Scheme Online Item!Dataset Summary:This feature service provides access to current and historical drought intensity categories for the entire USA. These data have been produced weekly since January 4, 2000 by the U.S. Drought Monitor and the full time series is archived here. Drought intensity is classified according to the deviation of precipitation, stream flow, and soil moisture content from historically established norms, in addition to subjective observations and reported impacts from more than 350 partners across the country. New map data is released every Thursday to reflect the conditions of the previous week.Layer Summary:'US_Drought': Time series containing polygon areas by week'US_Drought_Current': Polygon areas for most recent weekTable Summary:'US_Drought_by_State': Drought Conditions Table by state by week'US_Drought_by_County':Drought Conditions Table by county by weekThe tables contain a series of drought classification summaries that fall into two groups: Categorical Percent Area and Cumulative Percent Area.

Categorical Percent Area statistic is the percent of the area in a certain drought category and excludes areas that are better or worse. For example, the D0 category is labeled as such and only shows the percent of the area experiencing abnormally dry conditions.

Cumulative Percent Area statistics combine drought categories for a comprehensive percent of area in drought. For example, the D0-D4 category shows the percent of the area that is classified as D0 or worse.Drought Classification Categories are as follows:

Class Description Possible Impacts

D0 Abnormally Dry Going into drought: short-term dryness slows growth of crops/pastures. Coming out of drought: some lingering water deficits; drops/pastures not fully recovered.

D1 Moderate Drought Some damage to crops/pastures; streams, reservoirs, or wells are low with some water shortages developing or imminent; voluntary water-use restrictions requested.

D2 Severe Drought Crop/pasture losses are likely; water shortages are common and water retrictions are imposed.

D3 Extreme Drought Major crop/pasture losses; widespread water shortages or restrictions.

D4 Exceptional Drought Exceptional and widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells creating water emergencies. The U.S. Drought Monitor is produced in partnership between the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. It is the drought map that the USDA and IRS use to define which farms have been affected by drought conditions, defining who is eligible for federal relief funds.RevisionsJul 5, 2024: Rebuilt dataset from source provider in order to correct gaps in missing or reclassified data.If you would like to be alerted to potential issues or simply see when this Service will update next, please visit our Live Feed Status Page!

Historic Agricultural Drought Frequency Maps depict the frequency of severe drought in areas where 30 percent/50 percent of the cropland/grassland has been affected. The historical frequency of severe droughts (as defined by ASI) is based on the entire ASI times series (1984-2023).Phenomenon Mapped: Historic Drought FrequencyUnits: Frequency (percentage)Time Interval: Multi-annualTime Extent: 1984-2023Cell Size: 1 kmPixel Type: 32-bit Signed IntegerData Projection: WGS 1984Mosaic Projection: WGS 1984 Web MercatorSource: Food and Agriculture Organization of the United NationsUpdate Cycle: Annual, 5th of July for the previous crop yearFormula: The number of years when land affected>30 percent/50 percent occurred/(2023-1984+1) *100Pixel value ranges from 0-100 (unit: percentage). Flag: 252: no data; 253: no season; 254: no cropland/grassland.Explore this and related data in this web application.More information please visit FAO GIEWS Earth Observation website

With a risk index score of 9.9, Somalia was the country most exposed to drought risk worldwide in 2024. Namibia and Zimbabwe tied for second, with a risk index score of 9.4. That year, five out of the 10 countries most exposed to drought hazard worldwide were located in Africa.

Drought occurs when a region has an imbalance between water supply and water demand over an extended period of time. Droughts can have significant environmental, economic, and social consequences. Between 1980 and the present time, the cost of drought exceeded 100 billion dollars, making drought monitoring a key factor in planning, preparedness, and mitigation efforts at all levels of government.Data Source: U.S. Drought Monitor, National Drought Mitigation Center, GISData DownloadUpdate Frequency:  Weekly, typically on Friday around 10:00AM UTC. Using the Aggregated Live Feed MethodologyFor Full Historical data: See USA Drought Intensity 2000 - Present Online Item!For Standard Symbology Style: See USA Drought Intensity - Current Conditions - Standard Color Scheme Online Item!Dataset Summary:This feature service provides access to current drought intensity categories for the entire USA. These data have been produced weekly since January 4, 2000 by the U.S. Drought Monitor, see the Full Historical data for the full time series. Drought intensity is classified according to the deviation of precipitation, stream flow, and soil moisture content from historically established norms, in addition to subjective observations and reported impacts from more than 350 partners across the country. New map data is released every Thursday to reflect the conditions of the previous week.Layer Summary:'US_Drought_Current': Polygon areas for most recent weekThis Layer contains a series of drought classification summaries that fall into two groups: Categorical Percent Area and Cumulative Percent Area.Categorical Percent Area statistic is the percent of the area in a certain drought category and excludes areas that are better or worse. For example, the D0 category is labeled as such and only shows the percent of the area experiencing abnormally dry conditions.Cumulative Percent Area statistics combine drought categories for a comprehensive percent of area in drought. For example, the D0-D4 category shows the percent of the area that is classified as D0 or worse.Drought Classification Categories are as follows:ClassDescriptionPossible ImpactsD0Abnormally DryGoing into drought: short-term dryness slows growth of crops/pastures. Coming out of drought: some lingering water deficits; drops/pastures not fully recovered.D1Moderate DroughtSome damage to crops/pastures; streams, reservoirs, or wells are low with some water shortages developing or imminent; voluntary water-use restrictions requested.D2Severe DroughtCrop/pasture losses are likely; water shortages are common and water retrictions are imposed.D3Extreme DroughtMajor crop/pasture losses; widespread water shortages or restrictions.D4Exceptional DroughtExceptional and widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells creating water emergencies.The U.S. Drought Monitor is produced in partnership between the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. It is the drought map that the USDA and IRS use to define which farms have been affected by drought conditions, defining who is eligible for federal relief funds.

China has been impacted by more drought-related disasters than any other country over the past three decades, with 34 events occurring between 1990 and 2023. The U.S. ranked second, with 18 drought events recorded during this period. In 2023, more than 29 million people were affected by drought worldwide.

Per California Water Code Section 10609.80 (a), DWR has released an update to the indicators analyzed for the rural communities water shortage vulnerability analysis and a new interactive tool to explore the data. This page remains to archive the original dataset, but for more current information, please see the following pages: - https://water.ca.gov/Programs/Water-Use-And-Efficiency/SB-552/SB-552-Tool - https://data.cnra.ca.gov/dataset/water-shortage-vulnerability-technical-methods - https://data.cnra.ca.gov/dataset/i07-water-shortage-vulnerability-sections - https://data.cnra.ca.gov/dataset/i07-water-shortage-social-vulnerability-blockgroup This dataset is made publicly available pursuant to California Water Code Section 10609.42 which directs the California Department of Water Resources to identify small water suppliers and rural communities that may be at risk of drought and water shortage vulnerability and propose to the Governor and Legislature recommendations and information in support of improving the drought preparedness of small water suppliers and rural communities. As of March 2021, two datasets are offered here for download. The background information, results synthesis, methods and all reports submitted to the legislature are available here: https://water.ca.gov/Programs/Water-Use-And-Efficiency/2018-Water-Conservation-Legislation/County-Drought-Planning Two online interactive dashboards are available here to explore the datasets and findings. https://dwr.maps.arcgis.com/apps/MapSeries/index.html?appid=3353b370f7844f468ca16b8316fa3c7b The following datasets are offered here for download and for those who want to explore the data in tabular format. (1) Small Water Suppliers: In total, 2,419 small water suppliers were examined for their relative risk of drought and water shortage. Of these, 2,244 are community water systems. The remaining 175 systems analyzed are small non-community non-transient water systems that serve schools for which there is available spatial information. This dataset contains the final risk score and individual risk factors for each supplier examined. Spatial boundaries of water suppliers' service areas were used to calculate the extent and severity of each suppliers' exposure to projected climate changes (temperature, wildfire, and sea level rise) and to current environmental conditions and events. The boundaries used to represent service areas are available for download from the California Drinking Water System Area Boundaries, located on the California State Geoportal, which is available online for download at https://gispublic.waterboards.ca.gov/portal/home/item.html?id=fbba842bf134497c9d611ad506ec48cc (2) Rural Communities: In total 4,987 communities, represented by US Census Block Groups, were analyzed for their relative risk of drought and water shortage. Communities with a record of one or more domestic well installed within the past 50 years are included in the analysis. Each community examined received a numeric risk score, which is derived from a set of indicators developed from a stakeholder process. Indicators used to estimate risk represented three key components: (1) the exposure of suppliers and communities to hazardous conditions and events, (2) the physical and social vulnerability of communities to the exposure, and (3) recent history of shortage and drought impacts. The unit of analysis for the rural communities, also referred to as "self-supplied communities" is U.S. Census Block Groups (ACS 2012-2016 Tiger Shapefile). The Census Block Groups do not necessarily represent socially-defined communities, but they do cover areas where population resides. Using this spatial unit for this analysis allows us to access demographic information that is otherwise not available in small geographic units.

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 (RIM) model. The data include county-level variables on drought hazards, damages, socioeconomic, and environmental variables for the time period 1991-2010.

A drought is a natural hazard that is characterized by an extended period of dryness or a deficiency or lack of precipitation. Droughts are normal for many climate zones and are a natural part of climate variability. They may last for weeks, months, or even years. There are four types of drought:An agricultural drought occurs when there is not enough soil moisture to grow crops. This can be due to a lack of precipitation or reduced groundwater or reservoir levels needed to maintain irrigation.A hydrological drought occurs when surface or groundwater levels decrease. This could be due to reduced precipitation totals or overuse.A meteorological drought occurs when a place receives less precipitation than normal.A socioeconomic drought occurs when the demand for a good exceeds the supply due to a weather-related deficit in water.Drought has many interconnected impacts. The most obvious are those influencing the agriculture industry. Without enough water, crops fail, which results in food shortages for humans and livestock. This drives up prices, causing some families to go without the goods impacted by the dry spell. While irrigation from surface or groundwater sources may be able to alleviate the issue in the short term, these have their own drawbacks. For example, pumping groundwater at a faster rate than it can be replenished (if it can be replenished) will lead to land subsidence, which can damage critical infrastructure or make room for seawater intrusion in coastal regions, killing salt intolerant species–including crops–or causing contamination of drinking water.Humans are not the only organisms affected by drought. Without water, native plants may wither and animals may have to travel long distances to access water or die of thirst. The lack of water can lead to local extinction events or landscape or ecosystem changes in favor of species with lower water needs. Dry vegetation can also become fuel for wildfires sparked by lightning or human activity.Life cannot exist without water, which is perhaps why the first cities formed along rivers. As with all natural resources, rules and regulations have been created surrounding the use and protection of this vital commodity. One of the most infamous and influential in the United States is the Colorado River Compact of 1922. The Compact was written during a noted wet period in history and allotted amounts of water from the Colorado River to the U.S. states of Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming. This is the document regional water rights and laws have since been built upon. In spite of not taking into consideration the water needs of Native Americans forced onto regional reservations or of Mexico, each state was permitted to take a designated amount from the river. Mexico was eventually allotted water in a treaty signed in 1944, although the Colorado River runs dry before it reaches the Gulf of California.Droughts have played an important role throughout history. They are suspected to have spurred human migration out of Africa and ended civilizations such as the Mayan Empire. The Dust Bowl hit the Great Plains region of the United States from 1930 to 1936. This displaced an estimated 2 million people and led to disease outbreaks among people weakened by malnutrition as a result of crop failures due to poor land management practices in the prior decades, topsoil erosion, and a severe drought.As Earth’s climate continues to warm, models show dry places are likely to become drier. Rising temperatures facilitate quicker evaporation, increasing drought risk or prolonging ongoing droughts.It is important to practice water conservation whether your region is experiencing a drought or not. On a larger scale, you can advocate for water conservation legislation by writing, calling, or voting for leaders who are working toward systemic change. Here are some things you can implement on a personal level:Capture water you use while you are washing your hands or waiting for the shower to get warm and use that water for your house plants or your garden.Fix or call a plumber to repair any leaks in your plumbing or faucets.Install low-flow fixtures or appliances, use low-volume toilets, or retrofit existing faucets with flow restrictors.Compost food scraps rather than putting them in the garbage disposal.Plant native or drought-tolerant plants on your property.Harvest rainwater.Water plants and gardens by hand or choose water-efficient irrigation systems with a smart, weather-based controller and check the systems regularly to be sure they are watering plants and not pavement.Reduce the amount of fertilizer you use as it increases the amount of water needed.Mow your lawn at 3 inches or higher to encourage grass to root more deeply and hold soil moisture. Mulch your garden to help the soil retain moisture and keep weeds at bay that would compete with your plants for water.Keep your pool covered to minimize water evaporation.Take shorter showers.Only use the laundry machine or dishwasher when they are full, and use water-saving features if available.Wash your car at a car wash that recycles water or wash it less often or not at all.Drought intensity data from the National Drought Mitigation Center’s United States Drought Monitor is calculated from measures of precipitation, stream flow, and soil moisture. Scientists look at long-term averages and compare current conditions to determine if a region is drier or wetter than it has been historically. This real-time dataset updates every Friday around 10 a.m. coordinated universal time and displays conditions for the previous week. The data has been classified into five categories: abnormally dry, moderate drought, severe drought, extreme drought, and exceptional drought.Under abnormally dry conditions, one might observe slower plant growth or lower water availability. During moderate drought, crops may be damaged and water shortages may develop, triggering some municipalities to request residents implement water-use restrictions, such as turning off sprinkler systems. Under severe drought conditions, crop losses become likely, water shortages are common, and water-use restrictions would be implemented with fines issued to those who do not follow them. Extreme drought would result in major crop losses and widespread water deficits and use restrictions. Finally, exceptional drought would lead to exceptional losses in agriculture and water emergencies.

The Canadian Drought Monitor (CDM) brings together Agriculture and Agri-Food Canada’s drought monitoring capabilities and collaboration with external agencies (federal and provincial) to produce, through analysis and consolidation of multiple indices and indicators, an easily understood comprehensive national drought severity map and report each month. The monitor provides specific details on agricultural impacts of the current drought situation, including statistics on land area, cattle, and the number of producers impacted.

The Canadian Drought Monitors are based on a five class system ranking the severity of the drought condition. The Monitor map identifies general drought areas, labelling droughts by intensity, with D1 being the least intense and D4 being the most intense. The classifications are as follows:

• D0 (Abnormally Dry) – represents an event that occurs once every 3-5 years;

• D1 (Moderate Drought) – represents an event that occurs every 5-10 years;

• D2 (Severe Drought) – represents an event that occurs every 10-20 years;

• D3 (Extreme Drought) – represents an event that occurs every 20-25 years; and

• D4 (Exceptional Drought) – represents an event that occurs every 50 years.

D0 is not recognized as a drought classification; however, it provides a warning of areas that are currently vulnerable to drought or areas that are recovering from drought.

As of February 5, 2025, approximately 14 percent of India's total land area was affected by drought conditions ranging from moderate to exceptional. This was less than double the amount affected by drought in the same month the previous year. In February 2024, around nine percent of India's land area suffered from extreme drought conditions.

Abstract: A CPC forecaster (from a rotating schedule of 5 as of August 2013) creates the Seasonal Drought Outlook map and narratives. The map, produced using GIS, shows where current drought areas are expected to improve, be removed, or persist with intensity, as well as new areas where drought may develop, at the end of the forecast period. The current drought areas are obtained from the most recent weekly U.S. Drought Monitor where drought is considered D1 (moderate drought) or worse. There are two narratives: a brief, general summary and a detailed, regional technical discussion that describes the thought process, forecast tools used, and confidence for each region on the map. These outlook products apply to the following 3-month period from the date of issue. Originally produced once a month on the third Thursday of each month, the SDOs were changed to twice a month in June 2007 (initial SDO third Thursday of month, updated SDO first Thursday of next month). Since June 30, 2013, however, the SDO is now produced once a month on the third Thursday. The forecast applies to all 50 states of the United States plus Puerto Rico.

Drought occurs when a region has an imbalance between water supply and water demand over an extended period of time. Droughts can have significant environmental, economic, and social consequences. Between 1980 and the present time, the cost of drought exceeded 100 billion dollars, making drought monitoring a key factor in planning, preparedness, and mitigation efforts at all levels of government. Data Source: U.S. Drought Monitor, National Drought Mitigation Center, GISData DownloadUpdate Frequency:  Weekly, typically on Friday around 10:00AM UTC. Using the Aggregated Live Feed MethodologyFor Full Historical data: See USA Drought Intensity 2000 - Present Online Item!For Default Symbology Style: See USA Drought Intensity - Current Conditions Online Item!Dataset Summary:This feature service provides access to current drought intensity categories for the entire USA. These data have been produced weekly since January 4, 2000 by the U.S. Drought Monitor, see the Full Historical data for the full time series. Drought intensity is classified according to the deviation of precipitation, stream flow, and soil moisture content from historically established norms, in addition to subjective observations and reported impacts from more than 350 partners across the country. New map data is released every Thursday to reflect the conditions of the previous week.Layer Summary:'US_Drought_Current': Polygon areas for most recent weekThis Layer contains a series of drought classification summaries that fall into two groups: Categorical Percent Area and Cumulative Percent Area.

Categorical Percent Area statistic is the percent of the area in a certain drought category and excludes areas that are better or worse. For example, the D0 category is labeled as such and only shows the percent of the area experiencing abnormally dry conditions.

Cumulative Percent Area statistics combine drought categories for a comprehensive percent of area in drought. For example, the D0-D4 category shows the percent of the area that is classified as D0 or worse.Drought Classification Categories are as follows:

Class Description Possible Impacts

D0 Abnormally Dry Going into drought: short-term dryness slows growth of crops/pastures. Coming out of drought: some lingering water deficits; drops/pastures not fully recovered.

D1 Moderate Drought Some damage to crops/pastures; streams, reservoirs, or wells are low with some water shortages developing or imminent; voluntary water-use restrictions requested.

D2 Severe Drought Crop/pasture losses are likely; water shortages are common and water retrictions are imposed.

D3 Extreme Drought Major crop/pasture losses; widespread water shortages or restrictions.

D4 Exceptional Drought Exceptional and widespread crop/pasture losses; shortages of water in reservoirs, streams, and wells creating water emergencies. The U.S. Drought Monitor is produced in partnership between the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. It is the drought map that the USDA and IRS use to define which farms have been affected by drought conditions, defining who is eligible for federal relief funds.

Drought: areas where the change in the Standardized Precipitation Index (SPI) is below -20%. The long-term change in annual drought is calculated over a 20 year time period, from 2041 to 2060 (mid term), with RCP 2.6 low emission scenario. Source: WCRP CORDEX - CMIP6/CORDEX (https://cordex.org/experiment-guidelines/cordex-cmip6/)

The extreme drought damage historical events data of the 34 key areas along One Belt One Road were collected from Internet. First, a Web crawler was coded by python language. Using several key words about extreme drought damage, web pages were then collected by Google and Baidu search engine. Last, important information about the extreme drought events (e.g., place, time, affected area, affected population, count of death) were extracted from web pages. This data can be used for risk assessment of extreme drought in the 34 key areas along One Belt One Road.

Drought Areas data description: This data layer is derived from copying the designated WRIAs. WRIAs data description: Water Resource Inventory Areas (WRIA) for Washington State at 1:24,000 scale. WRIAs were formalized under WAC 173-500-040 and authorized under the Water Resources Act of 1971, RCW 90.54. Ecology was given the responsibility for the development and management of these administrative and planning boundaries. These boundaries represent the administrative under pinning of this agency's business activities. The original WRIA boundary agreements and judgments were reached jointly by Washington's natural resource agencies (Ecology, Natural Resources, Fish and Wildlife) in 1970.

A CPC forecaster (from a rotating schedule of 5 as of August 2013) creates the Monthly Drought Outlook map and narratives. The map, produced using GIS, shows where current drought areas are expected to improve, be removed, or persist with intensity, as well as new areas where drought may develop, at the end of the forecast period. The current drought areas are obtained from the most recent weekly U.S. Drought Monitor where drought is considered D1 (moderate drought) or worse. There are two narratives: a brief, general summary and a detailed, regional technical discussion that describes the thought process, forecast tools used, and confidence for each region on the map. These outlook products apply to the following 1-month period from the date of issue. The MDO replaced the updated SDO (which had been released on the first Thursday of the month) starting on June 30, 2013, with the MDO released on the last day of the month. The forecast applies to all 50 states of the United States plus Puerto Rico.