What is drought?
Drought is a climate extreme characterised by persistent unusual dry weather conditions affecting the hydrological balance. The conditions are usually associated with lack of precipitation, deficit in soil moisture and water reservoir storage, leading to widespread impacts. Droughts can be exacerbated by heatwaves.
Drought is to be distinguished from aridity, a long-term climatic feature, and from water scarcity, a situation where the available water resources are insufficient to satisfy water demand.
The exact definition of drought depends on several factors, such as the prevailing effects on the hydrological cycle, the economic, environmental, socio-economic sector analysed for its dependency of the availability of freshwater.
Drought Stages
Droughts are commonly grouped into three basic types:
- Meteorological drought: it is generally defined as a period of unusual precipitation deficit, in relation to the long-term average conditions for a region.
- Agricultural/Ecological drought: it occurs when a meteorological drought leads to a soil moisture deficit that limits water availability for natural vegetation and crops.
- Hydrological drought: it is associated with the effects of prolonged periods of precipitation deficit and reduced surface or sub-surface water. For instance, reduced streamflow in rivers and creeks, reservoir and lake level lowering as well as groundwater level lowering.
Drought monitoring
Due to the different types of drought and its intrinsic complexity, drought monitoring needs to rely on a set of different indicators, representing several components of the hydrological cycle (e.g. precipitation, soil moisture, reservoir levels, river flow, groundwater levels) or impacts (e.g. vegetation water stress). Usually, indicators represent statistical anomalies of the current situation with respect to the long-term climatology at a given location and period of time.
In order to ease the interpretation and to provide information for decision-making, individual indicators can be logically combined into high-level indicators that highlight different warning levels with respect to a given economic sector or the natural system. An example is the Combined Drought Indicator (CDI), for agricultural and ecosystem drought, as shown in the Copernicus European and Global Drought Observatories (EDO & GDO).
Users can get access to all available information by using the Copernicus EDO/GDO web mapping service.
Our activities
Explore the drought situation in Europe and parameters such as rainfall, temperature, heatwaves, soil moisture, vegetation health, lowflow and groundwater availability.
Visualise the drought situation on the planet and for rainfall, soilmoisture, temperature, heatwaves, groundwater availability, soil moisture and vegetation response.
When severe droughts occur we publish ad-hoc reports detailing the situation, the forecasts and the impacts.
Find here a selection of our scientific publications on droughts.
Our latest news on droughts
Severe and prolonged drought events have affected Europe for more than two years and northern Africa for six years, causing water shortages and hampering vegetation growth.
Unprecedented drought and extreme heatwaves have affected the Amazon basin, threatening one of Earth’s most vibrant ecosystems and local communities.
The Atlas provides for the first time a comprehensive assessment and mapping of drought risks and impacts in the EU for a global warming of 1.5, 2 and 3 degrees.
Further reading
When severe droughts occur we resume their characteristics in reports, explaining the situation, the forecasts and the impacts if already reported in the media or by our partners.
Short explanation on how drought monitoring works and on which measured or modelled parameters we rely.
The parameters we display in the Mapviewer are based upon methodologies shortly explained in Factsheets, which we present on this page.
Drought monitioring relies on a series of datasets which all come available with a certain delay, On this page these delays are listed so that you can understand when you can expect a relevant update of our maps
We worked since 2007 on Drought monitoring as a team of scientists both at the JRC as well as with colleagues world-wide. Please find an excerpt of our scientific publications on this page.
With world-wide partners we execute projects that focus on collaboration to understand landscapes in other continents better for drought impacts, as well as on capacity building where we share our knowledge and experience with colleagues in sister institutions
In the European and Global Mapviewer you will find data delivered online from partners around Europe and the World, live integrated in our MapViewers, from this page you can go directly to their services to understand better a drought in their realm.