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Using infrared satellite data provided by the Moderate Resolution Imaging Spectroradiometer (MODIS), scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, have developed an automated system which maps the global distribution of thermal hot-spots in near-real-time, and displays the results on this web-site

In addition to the hot-spot data themselves, this page provides information (or links to information) which explains how the HIGP MODIS Thermal Alert System works. Any additional queries should be directed at the following people:

Queries about the web-site itself should be directed at the site administrator:

MODIS is one of four sensors carried on-board NASA's first Earth Observing System (EOS) satellite 'Terra', which was launched in December 1999. Another MODIS sensor was launched on the second EOS satellite 'Aqua' in May 2002. For each image of the Earth's surface that MODIS collects, the MODVOLC algorithm automatically scans each 1 kilometre pixel within it to check for the presence of high-temperature hot-spots. When a hot-spot is found the date, time, location, and intensity of the hot-spot are recorded. MODIS looks at every square kilometre of the Earth's surface every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows us to provide at least 4 hot-spot observations every two days. Each day we compile updated global maps which display the locations of all hot-spots detected in the previous 24 hour period. By clicking on our target areas you can 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales. Clicking on the 'Text Alert File' link (which can be found directly beneath the main map) launches another window which contains detailed information about the hot-spots you are looking at (click here for an explanation of the contents of this file).

Click on the following link to see the hot-spots detected by the HIGP MODIS Thermal Alert System today. A map of the globe will appear, and the green dots are hot-spots. The MODVOLC algorithm is currently ∼8 hours behind, and is updated every hour. With the exception of a couple of two week periods during late 2000 and early 2001 when the sensor malfunctioned, you have direct access to our complete global hot-spot archive.

Take me to the hot-spots

Publications and Information

  • A detailed description of the development and implementation of the nighttime MODVOLC algorithm is available in the following publications:

  • A description of the daytime MODVOLC algorithm, which has been in operation since January 2002, can be found here.
  • Scientists on the HIGP MODIS Thermal Alert Team also interact directly with other research and governmental agencies to provide timely information regarding the hot-spot data our system collects. This interaction often takes the form of relatively short descriptive reports, examples of which can be found below:


We would like to thank Rich Hucek, Andrey Savtchenko, and the members of the MODIS Science Data Support Team at Goddard Space Flight Center, for their efforts maintaining the MODIS data stream.

Use of the data

© 2004, University of Hawai'i. Data can only be published with our permission.

Site Administrator:

Eric Pilger pilger@higp.hawaii.edu

Hawai'i Institute of 
Geophysics and Planetology,
School of Ocean and 
Earth Science and Technology,
University of Hawai'i at Manoa

Last Update:
30 June 2004

Support for the HIGP MODIS Thermal Alert System provided by:

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