Earthquake

Based on data from the Sentinel-1A satellite, this image shows how and where the land uplifted and sank from the 7.8-magnitude earthquake that struck Nepal on 25 April 2015. The image was generated by the German Aerospace Center (DLR) Earth Observation Center (EOC) using data acquired by Sentinel-1A before and after the earthquake event. Image: DLR/EOC.

Definition

Sudden movement of a block of the Earth’s crust along a geological fault and associated ground shaking (IRDR Glossary).

Earthquake can be defined as the shaking of earth caused by waves moving on and below the earth's surface and causing: surface faulting, tremors vibration, liquefaction, landslides, aftershocks and/or tsunamis (WHO).

 

Facts and figures

The size or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake. These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake. For every unit increase in magnitude, there is roughly a thirty-fold increase in the energy released. Earthquake magnitude was traditionally measured on the Richter scale. It is often now calculated from seismic moment, which is proportional to the fault area multiplied by the average displacement on the fault (Australian Government).

There are four different types of earthquakes: tectonic, volcanic, collapse and explosion.

  • A tectonic earthquake is one that occurs when the earth's crust breaks due to geological forces on rocks and adjoining plates that cause physical and chemical changes.
  • A volcanic earthquake is any earthquake that results from tectonic forces which occur in conjunction with volcanic activity.
  • A collapse earthquake are small earthquakes in underground caverns and mines that are caused by seismic waves produced from the explosion of rock on the surface.
  • An explosion earthquake is an earthquake that is the result of the detonation of a nuclear and/or chemical device.
 

Related content on the Knowledge Portal

Data Source

Population Density Map. Image: Facebook Connectivity
Publishing institution: Facebook Connectivity Lab, Center for International Earth Science Information Network (CIESIN) - Columbia University
Facebook Connectivity Lab in collaboration with the Center for International Earth Science Information Network (CIESIN) at Colombia University combines machine vision AI with satellite imagery and census information to create population density maps. With the integration of demographic information, specifically related to age and gender, these maps collectively provide information on both the location and the demographic of a population in a certain country. The population density maps cover the majority of countries around the world.
Population Density Map. Image: Facebook Connectivity
Publishing institution: Facebook Connectivity Lab, Center for International Earth Science Information Network (CIESIN) - Columbia University
Facebook Connectivity Lab in collaboration with the Center for International Earth Science Information Network (CIESIN) at Colombia University combines machine vision AI with satellite imagery and census information to create population density maps. With the integration of demographic information, specifically related to age and gender, these maps collectively provide information on both the location and the demographic of a population in a certain country. The population density maps cover the majority of countries around the world.

Noticias

The signing ceremony of the ROSE-L mission. Image: ESA.

The European Commission plans to rapidly expand its environmental monitoring programme Copernicus. For this purpose, the European Space Agency (ESA) recently pledged 2.55 billion Euros towards contracts to advance the production of six new Copernicus satellite missions. The final of the six contracts was signed last Thursday between ESA and Thales Alenia Space for a mission that will provide new and important information to climate research and disaster management.

The high-priority Copernicus Radar Observation System for Europe in L-band (ROSE-L) mission is planned to launch in 2028 for a period of 7.5 years. The ROSE-L mission will orbit Earth every few days at an altitude of 690km and will carry a L-Band synthetic aperture radar (SAR). With a wavelength of approximately 23cm... read more

Publishing date: 18/12/2020
Participants at the virtual expert meeting. Image: UNOOSA.

In order to discuss and promote the use of space technologies in addressing natural hazards such as forest fires and landslides in Latin America, UN-SPIDER conducted a virtual regional expert meeting on the topic of “Space-based Solutions for Disaster Risk Reduction and Emergency Response in Latin America” from 22 to 24 September 2020. The meeting was jointly organized with UN-SPIDER Regional Support Offices from Argentina (National Space Activities Commission, CONAE), Brazil (Federal University of Santa Maria, UFSM), Colombia (Geographic Institute Agustin Condazzi, IGAC), and Mexico (Mexican Space Agency, AEM).

In Latin America, UN-SPIDER and its Regional Support Offices have regularly carried out regional expert meetings, training courses and other joint efforts since 2011. The last Regional Expert Meeting took place in 2017 in Mexico.

The meeting, which consisted of three two-hour-long sessions, brought together a total of over 200 disaster management stakeholders... read more

Publishing date: 28/09/2020
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 temperature, while storms affected the highest number of people. Published by the Centre for Research on the Epidemiology of Disasters (CRED), “Natural disasters 2019 - Now is the time to not give up” draws on data recorded in the Emergency Events Database (EM-DAT), which saw the addition of 396 disasters that affected a total of 95 million and caused $103 billion in economic losses around the world. 

Accounting for 40 per cent of disaster events, Asia suffered the highest impact with 45 per cent of deaths and 74 per cent of total affected. India, which saw cyclone Fani cause destruction in 2019, was the country most affected... read more

Publishing date: 20/08/2020

Evento

The University of Alaska Fairbanks has launched a MOOC about Synthetic Aperture Radar (SAR) remote sensing for disaster monitoring. SAR is a remote sensing technology that can see the ground even during darkness and through rain, clouds, or smoke. Participants of the course will gain an intuitive understanding of the information contained in SAR observations and learn to use a range of analysis techniques to apply SAR data to disaster mapping and management. Specific topics will include:

  • The mathematical and physical principles of SAR remote sensing
  • How to access and visualize SAR data
  • Interpretation of SAR images in the context of disaster monitoring
  • Interferometric SAR (InSAR) concepts
  • Flood mapping and SAR change detection for hazard analysis
  • InSAR-based analysis of volcanoes and landslides

The learned concepts will be put into practice in simulated disaster response exercises, in which participants will... read more

2nd Edition of World Congress on Geology & Earth Science logo. Image: Innovinc International

GeoEarth-2020 welcomes colleagues from all branches of Geosciences and from many countries in the world to participate to the second edition of thw 'World Congress on Geology and Earth Science'. The Conference will enable the sharing of best practices in Geoscience as well as exploring the role of remote sensing in monitoring Earth processes and dynamics.

The topics of the Conference include:

  • Environmental Geology, 
  • GIS, Remote Sensing and Geospatial Sciences, 
  • Marine Geosciences and Oceanography,
  • Groundwater and Hydrology: Surface Hydrology/Surface Water,
  • Rock Deformation and Structural Geology,
  • Volcanology and Plate Tectonics,
  • Earth, Ecology and Ecosystems,
  • Soil Science and Conservation of Soil Biodiversity.

Advisory Support

UN-SPIDER conducted a Institutional Strengthening Mission (ISM) in Myanmar from 28 March to 2 April 2017. The activity was a follow-up to the technical advisory mission conducted in March 2012, which was aimed at improving the utilization of space-based and geospatial information in all stages of disaster management. In November 2012, UN-SPIDER visited Myanmar to disseminate the report of the technical advisory mission and offered a training course on geo-informatics for disaster risk management in collaboration with the International Centre for Integrated Mountain Development (ICIMOD). As a follow-up activity aimed at taking account of the progress realized since 2012, UN-SPIDER revisited Myanmar in June 2016 and held a high-level advocacy meeting of stakeholders and a training course on Earth observation technologies for landslide hazard and risk assessment.

 
Mission dates: 28/03/2017 to 02/04/2017

As part of the technical advisory support it provides to countries worldwide, UN-SPIDER carried out an Institutional Strengthening Mission to Myanmar from 11 to 15 March 2019 upon the request of the government. This activity was jointly organized by UN-SPIDER and the United Nations Human Settlement Programme (UN-Habitat), under auspices of the Ministry of Social Welfare, Relief and Resettle­ment (MSWRR) of Myanmar. It was hosted by the Emergency Operation Centre (EOC). 

Mission dates: 11/03/2019 to 15/03/2019

At the request of, and in coordination with the National Civil Protection Office of Tunisia, UN-SPIDER is conducting a Technical Advisory Mission to Tunisia from 4 to 6 March 2020 to identify the needs of the country to fully take advantage of space-based information for disaster management. In order to discuss the use of space-based information for risk and disaster management to subsequently make recommendations on improvements, the expert team meets with key disaster management authorities in the country.

The mission is conducted with the support of experts from the Algerian Space Agency (ASAL); the Romanian Space Agency (ROSA); the United Nations Economic Commission for Africa (UNECA); the National Observatory of Athens (NOA); and an expert on the Copernicus Emergency Management Service. The mission team is also benefiting from the support of the Chief of Space Applications of the United Nations Office for Outer Space Affairs.

As part of the mission, the team of experts will visit several institutions including the National Office of Civil Protection; the Directorate General for Forests of the Ministry of Agriculture; the Faculty of Sciences of Tunis, University of Tunis El Manar; the National Agronomic Institute of Tunisia; the National Institute of Meteorology; as well as at the Ministry of Local Affairs and Environment. Meetings will also be conducted with representatives of the National Cartographic and Remote Sensing Centre of Tunisia and other organizations. In addition, the TAM team will meet the United Nations Country Team in Tunisia, which supports disaster management efforts in the country.

During the TAM, a workshop with over 20 participants from nine institutions will take place in order to present the UN-SPIDER programme to Tunisian counterparts involved in disaster management, and encourage inter-institutional cooperation and sharing of geospatial information among them.

UN-SPIDER aims at ensuring all countries have the capacity to use all types of space-based information to support risk and disaster management efforts. To make sure that all interested stakeholders can benefit from this information in the most effective way possible, UN-SPIDER provides Technical Advisory Support to Member States through missions such as this one.

The Algerian Space Agency (ASAL), the Romanian Space Agency (ROSA) and the National Observatory of Athens (NOA) are UN-SPIDER Regional Support Office.

On request of the Tunisian Government and immediately after the technical advisory mission, UN-SPIDER conducted a three-day hands-on training on the use of Sentinel-1 radar data for flood mapping. In order to further strengthen the capacity of Tunisia to use space technologies for disaster management, UN-SPIDER will continue to encourage the participation of Tunisian institutions in its conferences and expert meetings. In addition, together with its regional and international partners, UN-SPIDER will provide training on forest fire mapping in the medium term. 

Mission dates: 04/03/2020 to 06/03/2020

Pages

Hazard group

Terms in the same hazard group

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