Glacial Lake Outburst

The false-color images above show a glacial lake in the Himalayas nearly doubling in length over 30 years. Ice is represented as light blue, while significant meltwater is dark blue. Rocks are brown; vegetation is green. The growth of glacial lakes can increase the risk of flooding in nearby valleys. Image: NASA.

Definition

“Glacial lake outburst flood” (GLOF) is a phrase used to describe a sudden release of a significant amount of water retained in a glacial lake, irrespective of the cause. GLOFs are characterized by extreme peak discharges, often several times in excess of the maximum discharges of hydrometeorological induced floods, with an exceptional erosion/transport potential; therefore, they can turn into flow-type movements, e.g. GLOF-induced debris flows (Emmer).

Facts and figures

A GLOF may have diverse causes and subsequent mechanisms, for example accordingly on how water is released. Specific causes are related to specific mechanisms and not all their combinations are realistic scenarios. Moreover, specific subtypes of glacial lakes are susceptible to specific causes and subsequent mechanisms of outburst floods. Numerous studies have investigated the causes of lake outburst floods for specific lake subtypes and regions ; however, systematic investigation of the causes and mechanisms of GLOF, as well as database construction, are required in order to better understand the complex processes and, in turn, provide more effective hazard and risk management (Emmer).

 

The following direct causes of glacial lake outburst floods were documented:

  • Rapid slope movement into the lake
  • Heavy rainfall/snowmelt
  • Cascading processes (flood from a lake situated upstream)
  • Earthquake
  • Melting of ice incorporated in dam/forming the dam (including volcanic activity-triggered jökulhlaups)
  • Blocking of subsurface outflow tunnels (applies only to lakes without surface outflow or lakes with a combination of surface and subsurface outflow)
  • Long-term dam degradation (Emmer).

Related content on the Knowledge Portal

SAM Satellite

The satellites SPOT 1, 2 and 3 (Satellite Probatoire de l'Observation de la Terre) were the first generation of SPOT earth observation satellites operated by Spot Image.

The first generation SPOT satellites were built on the SPOT Mk.1 bus with a lifetime of three years.

The SPOT satellites were identical, with each carrying two identical HRV (High... read more

Launch date:
26/09/1993

The satellites SPOT 1, 2 and 3 (Satellite Probatoire de l'Observation de la Terre) were the first generation of SPOT earth observation satellites operated by Spot Image.

The first generation SPOT satellites were built on the SPOT Mk.1 bus with a lifetime of three years.

The SPOT satellites were identical, with each carrying two identical HRV (High... read more

Launch date:
22/01/1990

The satellites SPOT 1, 2 and 3 (Satellite Probatoire de l'Observation de la Terre) were the first generation of SPOT earth observation satellites operated by Spot Image.

The first generation SPOT satellites were built on the SPOT Mk.1 bus with a lifetime of three years.

The SPOT satellites were identical, with each carrying two identical HRV (High... read more

Launch date:
22/02/1986

Landsat 5 was launched from Vandenberg Air Force Base in California on March 1, 1984, and like Landsat 4, carried the Multispectral Scanner (MSS) and the Thematic Mapper (TM) instruments. Landsat 5 delivered Earth imaging data nearly 29 years - and set a Guinness World Record For 'Longest Operating Earth Observation Satellite', before being decommissioned on June 5, 2013.
The Landsat 5 satellite orbited the the Earth in a... read more

Launch date:
01/03/1984

Actualités

Screenshot of the SMAP tool in action. Image: NASA

Officially launched in 2015 by the National Aeronautics and Space Administration (NASA), the SMAP mission is an orbiting satellite that measures the amount of wetness in the top layer of soil incrementally every 2-3 days. These Soil Moisture Active Passive (SMAP) measurements rely on radiation frequencies that point to different levels of moisture on the surface of  earth’s soil and are useful for... read more

Publishing date: 25/11/2020
Cover of the IFRC World Disasters Report 2020. Image: Indian Red Cross Society.

A new report by the world’s largest humanitarian aid network highlights global disasters, populations most vulnerable to them and the efforts of local institutions in preventing, preparing for and responding to them. The 2020 edition of the World Disasters Report, “Come Heat or High Water”, was launched virtually from the offices of the International Federation of Red Cross and Red Crescent Societies (IFRC) in Vienna on November 16. This year’s report discusses climate- and weather-related disasters and their humanitarian impact. It argues for the usefulness of smart financing and space-based information in disaster... read more

Publishing date: 19/11/2020
A SpaceX Falcon 9 rocket launches the SAOCOM 1B satellite. Image: Manuel Mazzanti/CONAE

The Argentinean SAOCOM 1B satellite was successfully launched into orbit on 30 August 2020. Developed by the National Argentinean Space Commission (CONAE), this new satellite will join SAOCOM 1A and four Italian COSMO-SkyMed to complete the joint Italian-Argentinean Satellite System for Emergency Management (SIASGE). Like its predecessor, SAOCOM 1B was built in Argentina through a joint effort with private companies and universities. It will operate at an elevation of 620 kilometers above the surface of the Earth. A SpaceX Falcon 9 booster launched the satellite from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida, United States of America.

The SAOCOM 1B satellite has been fitted with a Synthetic Aperture Radar (SAR) sensor that makes use of microwaves in the electromagnetic L-band, which goes through clouds... read more

Publishing date: 14/09/2020
Regional Support Offices mentioned:
Tropical cyclone Fani over the eastern coast of India on 2 May 2019. Image: NASA.

According to the latest issue of an annual disaster statistics report, floods were the deadliest type of disasters in 2019, followed by extreme... read more

Publishing date: 20/08/2020

Événement

EO for Polar Science Workshop logo. Image: ESA
Polar regions have experienced the most rapid rates of warming in recent years and its expected impacts will exceed those forecasted for many other regions in the planet resulting in local, regional and globally significant consequences affecting natural ecosystems and human activities.
 
This workshop aims at assessing the latest advancement in the use of EO technology for Polar science, exploring the main challenges and opportunities for the coming decade and consulting with the community to contribute to define a common scientific agenda for the future.
 
Workshop Objectives:
  • Reviewing the progress and latest results in polar science with major focus on EO- advances in the domain of polar research and applications
  • Identifying the major Polar scientific challenges, observation gaps and research needs for the coming years
  • Exploring effective mechanisms to promote networking and... read more
CRYOSAT logo. Image: ESA

As well as providing critical information about ice, CryoSat has also demonstrated that it can offer a valuable source of data for oceanography, hydrology and geodesy.

The conference therefore provides a forum for international scientists and operational users to present and share state-of-the-art CryoSat-based results, its decadal contribution to science and future perspectives in the following areas:

  • Sea ice
  • Greenland and Antarctica icesheets
  • Glaciers and ice caps
  • Oceans and marine gravity... read more

Pages

Hazard group

Terms in the same hazard group

Zircon - This is a contributing Drupal Theme
Design by WeebPal.