This Copernicus Sentinel-1 image combines two acquisitions over the same area of eastern Iraq, one from 14 November 2018 before heavy rains fell and one from 26 November 2018 after the storms. The image reveals the extent of flash flooding in red, near the town of Kut. Image: modified Copernicus Sentinel data (2018), processed by ESA, CC BY-SA 3.0 IGO.


Flood is usually used as a general term to describe the overflow of water from a stream channel into normally dry land in the floodplain (riverine flooding), higher-than–normal levels along the coast and in lakes or reservoirs (coastal flooding) as well as ponding of water at or near the point where the rain fell (flash floods) (IRDR Glossary).

Facts and figures

Floods are the natural hazard with the highest frequency and the widest geographical distribution worldwide. According to the Organization for Economic Cooperation and Development (OECD)  flooding is one of the most common, widespread and destructive natural perils, affecting approximately 250 million people worldwide and causing more than $40 billion in damage and losses on an annual basis (OECD).

Flooding occurs most commonly from heavy rainfall when natural watercourses lack the capacity to convey excess water. It can also result from other phenomena, particularly in coastal areas, by a storm surge associated with a tropical cyclone, a tsunami or a high tide. Dam failure, triggered by an earthquake, for instance, will lead to flooding of the downstream area, even in dry weather conditions.

Various climatic and non-climatic processes can result in different types of floods: riverine floods, flash floods, urban floods, glacial lake outburst floods and coastal floods.

Flood magnitude depends on precipitation intensity, volume, timing and phase, from the antecedent conditions of rivers and the drainage basins (frozen or not or saturated soil moisture or unsaturated) and status. Climatological parameters that are likely to be affected by climate change are precipitation, windstorms, storm surges and sea-level rise (UNDRR).

When floodwaters recede, affected areas are often blanketed in silt and mud. The water and landscape can be contaminated with hazardous materials such as sharp debris, pesticides, fuel, and untreated sewage. Potentially dangerous mold blooms can quickly overwhelm water-soaked structures. Residents of flooded areas can be left without power and clean drinking water, leading to outbreaks of deadly waterborne diseases like typhoid, hepatitis A, and cholera (UNDRR).

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Data Source

Publishing institution: Technical University Munich (TUM)
The Database for Hydrological Time Series of Inland Waters (DAHITI) was developed by the Deutsches Geodätisches Forschungsinstitut der Technischen Universität München (DGFI-TUM) in 2013. DAHITI provides water level time series of lakes, reservoirs, rivers, and wetlands derived from multi-mission satellite altimetry for hydrological applications. All water level time series are free available for the user community after a short registration process. Altimeter Data For the estimation of water heights, multi-mission altimeter data are used. In detail, altimeter missions such as Topex (NASA, CNES), Jason-1 (NASA, CNES), Jason-2 (NASA, CNES, NOAA, EUMETSAT ), Jason-3 (NASA, CNES, NOAA, EUMETSAT ), GFO (US Navy), Envisat (ESA), ERS-1 (ESA), ERS-2 (ESA), Cryosat-2 (ESA), IceSAT (NASA), SARAL/AltiKa (ISRO, CNES) and Sentinel-3A (ESA) are used.
Screenshot of Global Flood Awareness System (GLoFAS)
Publishing institution: Copernicus Emergency Management Service (Copernicus EMS)
GloFAS is an interactive map which presents *forecasted meteorological data*, *predicted hydrological data*, such as stream flows categorized by their probability of occurring (hydrological Return-period), *static maps* of lakes and reservoirs included in the model and *reporting points* where additional forecast information is available. Access to real-time forecasts and forecast reruns from GloFAS is possible through a dedicated ftp service set-up by the GloFAS team upon request. Data is provided either as point time series or 2D grid series, both in netCDF format. Switch-over from version 1.0 to version 2.0 will be transparent to the user, with real-time forecasts from version 2.0 being automatically transferred from the release date, the 14th November 2018. , Requesting data for stations/points (only for river sections with upstream area larger than 1000 km2): Station ID(s) Name of station(s) Name of River(s) Name of country Station latitude(s)/longitude(s) Station upstream area(s) from provider (if available) Requesting data for areas: Latitudes/longitudes of the bounding box region
Publishing institution: OceanDataLab
The Ocean Virtual Laboratory is a web platform making satellite and in-situ data for ocean monitoring accessible. It presents one of multiple Syntool Web portals that promote the synergistic use of Ocean Remote Sensing data in a wider context of Oceanic and Atmospheric models or in-situ data. , ESA/SEOM Ocean Virtual Laboratory portal: SAR roughness Sentinel 1: Ocean Color: From Sentinel-2, Sentinel-3 and Meteosat. Chlorophyll: From VIIRS and MODIS Sea Surface Temperature, Sea level, Salinity, Wind, Current, Rain, Mean Square Slope, Sea ice concentration , ESA/DUE GlobCurrent portal: SAR roughness, Ocean Color, Chlorophyll, Sea surface temperature, Sea level, Salinity, Wind, Wave, Current, Rain, ESA SMOS Storm portal: Significant Wave height (SWH) Jason 2 and ALTIKA, SAR roughness Sentinel-1, Wind speed SMOS, SMAP, AMSR2 and ASCAT, wind barbs ASCAT, CNES Aviso'VIZ altimetry portal: Sea Surface Height Anomaly (SSHA) Jason-2 and SARAL, Sea Level Anomaly (SLA) Jason-2 and SARAL, Absolute Dynamic Anomaly (ADT) Jason-2 and SARAL, Mean Sea Level RIse, Sea Level Anomaly, Geostrophic current vectors and streamlines., ESA Sentinel3 Viewer: products from OLCI, SLSTR and SRAL sensors., CNES PEPS Sentinel-1 Ocean Viewer: SAR roughness Sentinel-1, ESA Sea Surface Salinity portal: SMOS salinity, SMAP salinity
Publishing institution: European Organization for the Exploitation of Meteorological Satellites (EUMETSAT)
Map Viewer that allows downloading and time series creation of Meteosat and Sentinel-3 products.
Publishing institution: National Aeronautics and Space Administration (NASA)
The Hazards Mapper home page is a base map of the world with darker shaded areas indicating higher population densities. Custom population estimates generated by the Hazards Mapper are provided by SEDAC’s Population Estimation Service (PES). Population and settlement data are based on SEDAC’s Global Rural-Urban Mapping Project (GRUMP) and Gridded Population of the World, version 3 (GPWv3) data collections. GPWv3 provides a resolution of roughly 4 km (2.5 miles) at the equator. This population resolution will increase significantly when the updated version, GPWv4, is released in 2016. “Our new population layer will be at a resolution of 1 km (0.6 miles) at the equator, which will give higher precision for smaller areas,” says de Sherbinin. Continuously updated data layers that can be overlaid on the base map are available from NASA’s EOSDIS, including data from SEDAC; NASA's Land, Atmosphere Near real-time Capability for EOS (LANCE); and Global Imagery Browse Services (GIBS)...., The default base map includes: Red dots indicating fires and other hotspots detected over the past 48 hours by NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) instrument; Colored circles indicating earthquakes over the past seven days from the USGS Earthquake Hazards Program; Icons indicating the location of individual dams, dam clusters, and nuclear power plants from SEDAC’s Global Reservoir and Dam and Population Exposure Estimates in Proximity to Nuclear Power Plants, Locations databases; and, Colored polygons indicating tornado and flood warnings issued by NOAA (U.S. locations only).
Publishing institution: Wetlands International
Satellite derived rainfall and flooding estimates based on data from NOAA/FEWS.


The Asia and Oceania regions are frequently affected by severe natural phenomena such as tropical cyclones, torrential monsoons, volcanic eruptions, yellow sandstorms, floods, sea ice, and wildfires. The importance of monitoring the climate and the environment is also increasing, which has prompted enhanced global interest in the field.

In this area, the new generation of meteorological and earth observation satellites provide frequent and extensive observational information for use in disaster prevention and climate monitoring/diagnostics; they are indispensable in today’s world. The Asia/Oceania Meteorological Satellite Users’ Conferences provide an excellent forum for satellite operators and users within the Asia/Oceania community to meet and enhance their joint efforts in the utilization of satellite data and products for better weather, climate, and disaster mitigation services.


An image of Niamey from a drone. Image: Drone Africa Services.

The government of Niger, in partnership with the World Bank and a team of local volunteers, steps up the gathering of data on Niamey’s exposure to floods using drone and open source data to support disaster preparedness.

The initiative started with a team of volunteers, students and young professionals who used an open source mobile application to build a database on exposed people and assets in Niamey, the capital city. 

The team has so far gathered about 15,000 data point on household and infrastructure in the region. Drone African Service, a Nigerien startup has been providing training on the use of drones to acquire high-resolution images of exposed people and facilities. This is further analyzed and modelled for flood risk of the most vulnerable communities, which will be further shared with Nigerien government authorities on the risk data portal.

Drone Africa Services trained the team on digital cartography using OpenStreetMaps and a mobile application... read more

Publishing date: 26/09/2018


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