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A type of volcanic event near an opening/vent in the Earth’s surface including volcanic eruptions of lava, ash, hot vapour, gas, and pyroclastic material (IRDR Glossary).
The majority of volcanoes in the world form along the boundaries of Earth's tectonic plates. When tectonic plates collide, one often plunges deep below the other in what's known as a subduction zone. Not all volcanoes are related to subduction: another way volcanoes can form is what's known as hotspot volcanism. In this situation, a zone of magmatic activity—or a hotspot—in the middle of a tectonic plate can push up through the crust to form a volcano. Although the hotspot itself is thought to be largely stationary, the tectonic plates continue their slow march, building a line of volcanoes or islands on the surface (National Geographic).
A volcano is currently active if it is erupting lava, releasing gas or generating seismic activity. An active volcano is labelled dormant if it has not erupted for a long time but could erupt again in the future. When a volcano has been dormant for more than 10 000 years, it is considered extinct. Volcanoes can remain inactive, or dormant, for hundreds or thousands of years before erupting again. During this time, they can become covered by vegetation, making them difficult to identify.
How explosive a volcanic eruption is depends on how easily magma can flow or trap gas. If magma is able to trap a large amount of gas, it can produce explosive eruptions. (Australian Government).
Over the last 11,500 years, more than 1,500 major eruptions have occurred, with approximately 500 in the Pacific "Ring of Fire" alone (PreventionWeb).
There are volcanoes on every continent, even Antarctica. Some 1,500 volcanoes are still considered potentially active around the world today; 161 of those—over 10 percent—sit within the boundaries of the United States (National Geographic).
There are different types of eruptive events. We can distinguish between primary and secondary events.
Primary events are:
Secondary events are:
Volcanoes can have many different appearances. The shape of a volcano provides clues to the type and size of eruption that occurred. Eruption types and sizes depend on what the magma is made up of. Three common volcano forms are:
In order to encourage the targeted retrieval of space-based information and data by disaster risk reduction practitioners, content on the Portal is systematically enriched with metadata. For instance, data sources are marked up with data about their file type, satellite/sensor and spatial coverage and whether they relate to the disaster risk management or emergency response phase. The tool features a range of filters that draw on the metadata, thereby allowing users to narrow down their search, for example, filtering available GIS software by hazard type. This ensures that users efficiently find the content that is most relevant to them. At the same time, the Portal encourages the discovery of resources related to those accessed by the user, by providing links to them on the same page. This allows for contextualisation and highlights links between resources…
read moreBased on optical and radar images of different resolutions, UNOSAT products are also enriched with the available baseline GIS datasets and crowdsourcing data. Satellite-derived analysis performed by UNOSAT is delivered in the form of GIS Data, Static Maps, Live Web Maps, and Reports, and is then shared with a wide range of end-users such as UN Agencies, International Organizations, and Governments.
The Global Human Settlement (GHS) framework produces global open source spatial information about the human presence on the planet over time. This is in the form of built up maps, population density maps and settlement maps. This information is generated with evidence-based analytics and knowledge using new spatial data mining technologies. The framework uses heterogeneous data including global archives of fine-scale satellite imagery, census data, and volunteered geographic information. The data is processed fully automatically and generates analytics and knowledge reporting objectively and systematically about the presence of population and built-up infrastructures.
The guidelines will be reviewed and updated periodically, in order to integrate new best practices and to be responsive to evolutions in technology and end-user needs. The IWG-SEM chair has the responsibility to initiate the review, by agreement of the Working Group.
The production and the maintenance of the guidelines are based on a joint effort by the members of the International Working Group on Satellite-based Emergency Mapping (IWG- SEM), a voluntary group of organizations involved in satellite-based emergency mapping. It was founded to improve cooperation, communication and professional standards among the global network of satellite-based emergency mapping providers. The chairperson of the group is nominated for a term of one year and is responsible for organizing the monthly telecons and bi-annual meetings. The current chair is from the Department of Geoinformatics, Z_GIS University of Salzburg / Spatial Services Ltd, Austria…
Intensive capacity development sessions for Pacific island countries (Cook Islands, Fiji, Kiribati, Micronesia (the Federated States of), Samoa, Solomon Islands, Tonga, and Vanuatu).
The project aims to enhance institutional and technical capacity for using geospatial data and technology applications and promote regional cooperation for sharing geospatial data for disaster management in Pacific island countries.
Developed for the needs of the ASEAN sub-region in Asia and the Pacific, the handbooks can also be adapted for use in other regions.
The handbooks have been developed through expert working groups, in collaboration with United Nations partners including UNOOSA/UN-SPIDER, UNITAR-UNOSAT, and OCHA. As well as extensive consultation with space agencies, national disaster management authorities and regional institutions, including GISTDA, LAPAN, ASEAN Coordinating Centre for Humanitarian Assistance on Disaster Management and Asian Institute of Technology.
For a comprehensive and objective analysis of the settlement patterns, the DLR additionally developed an approach to display the spatial networks between the mapped settlements. It enables the computation of various form and centrality measures to characterize settlement patterns, at different spatial units, ranging from global to local scale.
CEMS is a core service of the European Union’s Earth Observation programme Copernicus. It supports all phases of the disaster management cycle by delivering warnings and risk assessments of floods and forest fires and by providing geospatial information derived from satellite images on the impact of natural and man-made disasters all over the world (before, during or after a crisis). The two Mapping services of CEMS (Rapid Mapping, Risk and Recovery Mapping) are delivering products since April 2012. The Risk & Recovery Mapping provided for example information for preparedness, disaster risk assessment and risk reduction related to earthquakes in Nepal, several post-disaster assessments for flood and fire events, reconstruction and recovery monitoring in Haiti, and multi-risk assessments for the Azores Islands in Portugal.
CEMS is coordinated by the European Commission (joint coordination between the Directorate Generals ECHO, JRC, GROW). Activation requests…
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