Extreme Temperature

The image shows the heat emanating from Death Valley on 30 June 2013. The measurement is surface temperature as measured by the Thermal Infrared Sensor on the Landsat 8 satellite. The accompanying natural color view from the Operationa

Definition

A general term for temperature variations above (extreme heat) or below (extreme cold) normal conditions (IRDR Glossary).

Since climate varies regionally, the definition of an extreme temperature and its threshold will differ from location to location. In other words, an extreme value in one location may be within the normal range in a different location (WMO).

A simple method is to establish a specific threshold for temperature and extreme precipitation events and evaluate the extremes that occur over (or under) that given threshold. Another common mean of ascertaining thresholds is based on selecting the tail of distributions for temperature and precipitation.Statistical partitions such as by quartiles or percentiles of the distribution have provided a means for evaluating extremes (WMO).

Facts and figures

Heat waves

A period of marked unusual hot weather (maximum, minimum and daily average temperature) over a region persisting at least three consecutive days during the warm period of the year based on local (station-based) climatological conditions, with thermal conditions recorded above given thresholds. Heat waves differ from warm spells. Similar to heat waves, warm spells are defined as a persistent period of abnormal warm weather. A warm spell occurs at any time of the year, whereas heat waves can only occur in the warm season (WMO).

Cold waves

A period of marked and unusual cold weather characterized by a sharp and significant drop of air temperatures near the surface (maximum, minimum and daily average) over a large area and persisting below certain thresholds for at least two consecutive days during the cold season. “Cool spell” refers to persistently below-average temperature conditions occurring during the warm season (WMO).

Further information

GISS Surface Temperature Analysis (GISTEMP v3)
IPCC report on Managing the Risks of Extreme Events and Disasters to Advance Cl…
WMO Guidelines on the Definition and Monitoring of Extreme Weather and Climate …

UN-SPIDER Regional Support Offices with hazard-specific expertise

Title: Asian Disaster Reduction Center (ADRC)
Title: Greece Regional Support Office

Related content on the Knowledge Portal

  • AIRBUS data set
    Map
    Pleidas, TerraSar-X, SPOT and Elevation data available commercially from airbus, certain sample data sets at various locations available for free.
    Publishing institution:
    1. Airbus Defence & Space
  • Radiant Earth (Radiant Earth Foundation)
    The website: https://www.radiant.earth
    Help and Tutorials: https://help.radiant.earth/
    Demos & Use Cases: https://demos.radiant.earth/
    Publishing institution:
    1. Radiant Earth Foundation
  • EarthData (NASA)
    NASA's Earth Observing System Data and Information System (EOSDIS) is a program for archiving and distributing Earth science data from multiple missions to users.
    Publishing institution:
    1. NASA Earth Science Disasters Program
  • Ocean Virtual Laboratory (OVL - OceanDataLab, ESA)
    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:
    1. OceanDataLab
    2. European Space Agency (ESA)
  • Ocean Virtual Laboratory (OVL - OceanDataLab, ESA)
    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:
    1. OceanDataLab
    2. European Space Agency (ESA)
  • EUMETSAT Image Gallery
    Map Viewer that allows downloading and time series creation of meteosat products.
    Publishing institution:
    1. European Organization for the Exploitation of Meteorological Satellites (EUMETSAT)
  • Bilko
  • Application for Extracting and Exploring Analysis Ready Samples (AppEEARS - NASA)
    Screenshot of Application for Extracting and Exploring Analysis Ready Samples (AppEEARS)
    Publishing institution:
    1. National Aeronautics and Space Administration (NASA)
  • Remote Sensing Systems (RSS)
    Screenshot of Remote Sensing Systems (RSS)
    Publishing institution:
    1. Remote Sensing Systems (RSS)
  • Large‐Area Morphological Characterization of Urban Environments for Exposure Modelling
    Mapping of built-up height and share of built-up area for the example of the city of Munich. The estimated average built-up height features a mean absolute error (MAE) of 2.7 m (i.e., less than one floor) and the share of built-up area could be estimated with a MAE of 13.3 %, when compared to a reference data set.
    Publishing institution:
    1. German Aerospace Center (DLR)

Term Parents

Meteorological

UN-SPIDER Regional Support Offices with hazard-specific expertise

Title: Asian Disaster Reduction Center (ADRC)
Title: Greece Regional Support Office