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GFIMS Global Fire Information Management System
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What is GFIMS and who is it aimed at? |
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GFIMS integrates remote sensing and GIS technologies to deliver global MODIS hotspot/active
fire locations and burned areas to natural resource managers and other stakeholders around
the World. GFIMS is an operational system based on the Fire Information for Resource
Management System (FIRMS) which was developed by the University of Maryland with funds
from NASA. Click here for more information.
Data are provided in various formats, including email alerts, image subsets, WMS services
and KML, shape and text files. At the core of GFIMS there is the Web Fire Mapper,
a web mapping interface which displays near-real time hotspots/fires processed by the
MODIS Rapid Response System.
GFIMS is primarily aimed at supporting natural resource managers, researchers, planners
and policy makers by helping them understand when and where fires occur and delivering
the fire information in near real-time and in easy-to-use formats.
Each hotspot/active fire location represents the center of a 1km pixel (approximately)
flagged as containing one or more actively burning hotspots/fires within that pixel.
The hotspots/fires are detected using data from the MODIS (or Moderate Resolution
Imaging Spectroradiometer) instrument, on board NASA's Aqua and Terra satellites,
using a specific fire detection algorithm that makes use of the thermal band detection
characteristics of the sensor.
The components of GFIMS are: Web Fire Mapper (open source web mapping service), Email
Alerts, Text Files, Shape Files, KML Files, WMS (version 1.1.1), NASA WorldWind plugin
and MODIS image subsets.
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Fire data status / MODIS
Rapid Response System status |
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The MODIS hotspot/active fire data are processed by the MODIS Rapid Response System.
For more information, click on the MODIS Rapid Response
website and click
system status page for
more infornmation on this aspect.
If the Web Fire Mapper (open source web mapping service) does not work properly, or
you have not received your email alerts, it is possible that the issue is either caused
by the GFIMS system or by the source of the data, the MODIS Rapid Response System.
Please check the system status if there is a lag in the update of the fire data.
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MODIS Fire Product User's Guide |
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For more information on the hotspot/active fire product and other MODIS fire products,
please refer to the MODIS
Collection 5 Active Fire Product User's Guide (version 2.4).
The guide provides the most current information regarding the Terra and Aqua MODIS
Active Fire Products. It is intended to provide the end user with practical information
regarding their use and misuse, and to explain some of the more obscure and potentially
confusing aspects of the fire products and MODIS products in general.
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Citation Information |
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Please include a bibliographic citation for the hotspot/active fire data that you
have used in your publications. Such citations will enable others to find the data
and see how the data have been used.
The following reference is for the GFIMS/FIRMS website and project:
Davies, D.K., Ilavajhala, S., Wong, M.M., and Justice, C.O. 2009. Fire Information for
Resource Management System: Archiving and Distributing MODIS Active Fire Data. IEEE
Transactions on Geoscience and Remote Sensing 47 (1):72-79.
The following reference provides a brief description of Web Fire Mapper website:
Justice, C.O., Giglio, L., Korontzi, S., Owens, J., Morisette, J.T., Roy, D., Descloitres,
J., Alleaume, S., Petitcolin, F., and Kaufman, Y. 2002. The MODIS fire products. Remote
Sensing of Environment 83, 244-262
The following reference provides a description of the algorithm used to produce the
MODIS active fire product:
Giglio, L., J. Descloitres, et al. 2003. An Enhanced Contextual Fire Detection Algorithm
for MODIS. Remote Sensing of Environment 87(2-3): 273-282.
Data reference:
FAO/NASA/University of Maryland. 2010. MODIS Hotspot / Active Fire Detections. Data set.
MODIS Rapid Response Project, NASA/GSFC [producer], FAO of UN, Global Fire Information
Management System [distributors]. Available on-line
[http://www.fao.org/nr/gfims/]
Please notify us of your
publications that use the
MODIS hotspot/active fire data. This allows us to provide information to the user
community on how the fire data have been used, and we can keep our product-related
references current. We request a bibliographic citation to your work and, if possible, a
copy of the publication.
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What is MODIS? |
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MODIS stands for MODerate Resolution Imaging Spectroradiometer. The MODIS instrument
is on board NASA’s Earth Observing System (EOS) Terra (EOS AM) and Aqua (EOS PM)
satellites. The orbit of the Terra satellite goes from north to south across the
equator in the morning and Aqua passes south to north over the equator in the afternoon
resulting in global coverage every 1 to 2 days. The EOS satellites have a ±55
degree scanning pattern and orbit at 705 km with a 2,330 km swath width.
For an artist’s visualization of “MODIS scans the globe” go to:
http://aqua.nasa.gov/doc/viz/media/aqua_modis_soren.mov.
(Higher resolution movie files can be found at:
http://aqua.nasa.gov/about/instrument_modis.php).
The MODIS instrument provides 36 spectral bands from wavelengths of 0.4µm to 14.4µm.
For more information, please visit the NASA MODIS website.
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When were the Terra and Aqua satellites launched? |
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Terra (EOS AM) was launched 18
December 1999 and Aqua (EOS PM) was launched
4 May 2002. High quality hotspot/active fire observations are available from the
Terra satellite starting November 2000 and from the Aqua satellite starting 4 July
2002 onwards.
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What time does the satellite pass over my area? |
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Terra (EOS AM) passes over the equator at approximately 10:30 am and 10:30 pm each
day, Aqua (EOS PM) satellite passes over the equator at approximately 1:30 pm and 1:30 am.
The sun-synchronous orbit allows the satellites to pass over the same area at the
same time in every 24 hour period (at every 99 minute orbit the satellites cross
the equator at the above mentioned times; every other spot on Earth has similarly
constant overpass times). The time of satellite pass will vary according to your
location. To estimate when the satellite will pass over your area, you can use the
satellite
overpass predictor provided by NASA. Daily Terra and Aqua global and
regional orbit tracks are provided by the Space Science and Engineering Center (SSEC)
at University of Wisconsin-Madison. The maps show a series of white lines with tic
marks showing what time the satellite will pass over a certain location on the Earth.
The white lines represent the center of the swath and the tic marks and time show
at what time in UTC the satellite has passed over that location. Click on the following
links for Aqua
Orbital Tracks or Terra
Orbital Tracks. Please refer to the MODIS Rapid Response System FAQ for more
information: “What do the orbit track maps show?”
For an artist’s visualization of “MODIS scans the globe” go to:
http://aqua.nasa.gov/doc/viz/media/aqua_modis_soren.mov.
(Higher resolution movie files can be found at:
http://aqua.nasa.gov/about/instrument_modis.php).
If you wish to view the MODIS near-real time swath image that corresponds to the
hotspot/active fire detections, please go to the following website:
http://rapidfire.sci.gsfc.nasa.gov/realtime/.
All times are in UTC (Coordinated Universal Time).
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How often are the hotspot / fire data acquired? |
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The MODIS instrument on board the Terra and Aqua EOS satellites acquire data continuously
providing global coverage every 1-2 days. Therefore there are at least 4 daily MODIS
observations for almost every area on the equator – with the number of overpasses
increasing (due to overlapping orbits) the closer an area is to the poles. See "What
time does the satellite pass over my area?"
It takes approximately 2 – 4 hours after satellite overpass for MODIS Rapid Response
to process the data, and for GFIMS to update the website. Occasionally, hardware errors
mean that it takes longer the 2-4 hours to process the data. For information on the
system status of MODIS Rapid Response, see
http://rapidfire.sci.gsfc.nasa.gov/status/.
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What is the plan after MODIS? |
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The designed life span for the Terra and Aqua satellites was 6 years. The Terra
satellite is effectively coming to the end of its predicted lifespan, as has happened
in the past with many other spacecraft. The
Visible
Imaging Infrared Radiometer Suite
(VIIRS) is being developed to extend the measurement series of the MODIS sensor,
currently flying aboard EOS' Terra and Aqua satellites. The VIIRS sensor is part of
the National
Polar-orbiting Operational Environmental Satellite System (NPOESS)
Preparatory Project
(NPP) - a joint NASA/IPO instrument risk reduction project. The
success of MODIS, and of the Terra and Aqua platforms in providing earth observations,
has set the bar for the next generation of instruments and spacecraft for the continuity
of Earth observation.
The launch schedule for NPP is currently still under review.
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What is NPP? |
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NPP is the
NPOESS (National
Polar-orbiting Operational Environmental Satellite System) Preparatory Project.
It is a joint mission between NASA and the NPOESS Integrated Program Office (IPO).
NPP's mission is to collect and distribute remotely sensed data for the land, ocean
and atmosphere for meteorological and global climate change studies. It allows for
the transition from Earth observing (EOS) missions carried out by satellites such as
Terra and Aqua to NPOESS. NPP will provide data such as atmospheric and sea surface
temperatures, humidity soundings, land and ocean biological productivity, and cloud
and aerosol properties. For more information, go
to: http://npoess.noaa.gov/index.php
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What is VIIRS? |
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The Visible
Imaging Infrared Radiometer Suite (VIIRS) is similar to MODIS, with somewhat fewer
bands but with most having higher spatial resolution than their MODIS counterpart. Like
MODIS, VIIRS has a high-dynamic-range band specifically for fire monitoring, from
which several standard active fire products will be produced.
For more information: http://npoess.noaa.gov/index.php?pg=viirs
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What is a MODIS hotspot/fire detection? |
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A MODIS hotspot/active fire location represents the center of a 1km (approx.) pixel
flagged as containing one or more actively burning hotspots/fires. The hotspots/fires
are detected using data from the MODIS (or Moderate Resolution Imaging Spectroradiometer)
instrument, on board NASA’s Aqua and Terra satellites. In most cases, MODIS hotspots are
vegetation fires, but sometimes it is a volcanic eruption or the flare from a gas well.
There is no way of knowing which type of thermal anomaly is detected based on the MODIS
data alone.
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How are hotspots/fires detected? |
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The hotspot/active fire detections are processed by the MODIS Rapid Response
System using the same algorithm as the standard MODIS
MOD14/MYD14 Fire and
Thermal Anomalies product. Fire detection is performed using a contextual
algorithm that exploits the strong emission of mid-infrared radiation from fires. The
algorithm
examines each pixel of the MODIS swath, and ultimately assigns to each
one of the following classes: missing data, cloud, water, non-fire, fire, or unknown.
More information can be found in
Giglio et al. (2003).
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What does a hotspot/fire detection mean on the ground? |
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Each hotspot/active fire detection represents the center of a 1km (approx.) pixel
flagged as containing one or more hotspots/fires within that pixel. The "location"
is the centre point of the pixel (not necessarily the coordinates of the actual fire).
The actual pixel size varies with the scan and track (see: What does scan and track mean?).
The hotspot/fire is often less than 1km in size (see: What size hotspots/fires can
be detected?).We are not able to determine the exact hotspot/fire size, what we do
know is that at least one hotspot/fire is located within that 1km pixel. Sometimes
you will see several active hotspots/fires in a line. This generally represents a
fire front.
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What size hotspots/fires can be detected? |
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In any given scene the minimum detectable fire size is a function of many different
variables (scan angle, biome, sun position, land surface temperature, cloud cover,
amount of smoke and wind direction, etc.), so the precise value will vary slightly
with these conditions. MODIS routinely detects both flaming and smouldering fires
1000 m² in size. Under very good observing conditions (e.g. near nadir, little or
no smoke, relatively homogeneous land surface, etc.) flaming fires one tenth this
size can be detected. Under pristine (and extremely rare) observing conditions even
smaller flaming fires 50 m² can be detected.
Unlike most contextual fire detection algorithms designed for satellite sensors that
were never intended for fire monitoring (e.g. AVHRR, VIRS, ATSR), there is no upper
limit to the largest and/or hottest fire that can be detected with MODIS.
The above diagram show the day and night relationship of fire size and fire temperature,
in different biomes, to the probability of being detected by MODIS (Giglio et al. 2003).
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I only see fire data available
for the last 7 days on your website. How can I get older data? |
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A download tool is being developed which will automate the process of accessing
data from the archive, but for now if the data you require are not available from
our website (see: data formats table for full list) then
please contact us.
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Factors Affecting Fire Detections
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Why did MODIS not detect a particular fire? |
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There are several reasons why MODIS may not have detected a certain fire. The fire may
have started and ended between satellite overpasses. The fire may have been too small
or too cool to be detected in the 1 km² MODIS footprint. Cloud cover, heavy smoke,
or tree canopy may completely obscure a fire. Occasionally the MODIS instruments
are inoperable for extended periods of time (e.g. the Terra MODIS in September 2000)
and can of course observe nothing during these times. To find out the status of MODIS
and the MODIS Rapid Response system go to:
http://rapidfire.sci.gsfc.nasa.gov/status/.
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How do I know if a hotspot/fire
detection was missed due to cloud or missing data? |
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An indication of cloud cover or missing data is not yet included in GFIMS. If you
want to know whether the MODIS Rapid Response system may have failed to report some
hotspots/fires due to cloud or missing data, you can look on the MODIS Rapid Response
Real-Time
website. There you can view the MODIS near-real-time level 2 browse images
which clearly show satellite coverage and cloud at the time of overpass. To take cloud
and missing data in to account, it may be more appropriate to use one of the 1-km Level
3 or CMG fire products.
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Why do you not see the
same fire twice in subsequent overpasses? |
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This is due to the dynamic and diurnal patterns associated with fire. Fires move
across the landscape at varying rates, depending on multiple factors including,
for example, the underlying vegetation type and the specific characteristics of
the fire, and therefore may be present in different locations when the satellites
pass overhead. In addition, the inherent diurnal burn-up and die-down patterns of
a fire can impact whether one can see the same fire twice.
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Do cloud shadows affect hotspot/fire detections? |
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Cloud shadows do not significantly affect hotspot fire detections.
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Can MODIS detect fires
below the forest canopy? |
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The likelihood of detecting a fire beneath the tree canopy is unknown, but likely to
be very low. Understory fires are typically small, and with the tree canopy obstructing
the view of the fire, detection will be very unlikely.
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How does the view angle
of the MODIS instrument affect hotspot/fire detections? |
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The wider the view, the larger the pixel field of view (the ground space covered).
As a result, you would need a proportionately larger fire area to achieve the same
likelihood of detection at nadir for most algorithms. This necessity is incorporated
into quality control reporting.
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How does air temperature
affect fire detection? |
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Differences in air temperature have a negligible effect on fire detection. Differences
in surface temperature, however, have a much larger impact as warmer areas like sandbeds,
rock outcrops, etc., can cause false positives. Filters incorporated into the algorithms
attempt to correct for this.
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How appropriate are the 1km MODIS
hotspot/fire locations for my research? |
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The MODIS hotspot/fire locations are good for determining the location of active fires,
providing information on the spatial and temporal distribution of fires and comparing
data between years. The 1km (approx.) MODIS hotspot/active fire pixel locations may not
always be the most appropriate source of fire related information. The data do not
provide any information on cloud cover or missing data. Depending on the analysis
you are performing, it is sometimes possible to derive misleading or even incorrect
results by ignoring the other types of pixels. In some cases it is more appropriate
to use one of the 1km Level 3 or
CMG
fire products. For more information, refer to the
MODIS
Collection 5 Active Fire Product User's Guide.
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What is the Climate Modeling
Grid (CMG) fire product? |
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The CMG fire products are gridded statistical summaries of fire pixel information
intended for use in regional and global modeling. The products are currently generated
at 0.5 degree spatial resolution for time periods of one calendar month
(MOD14CMH/MYD14CMH) and eight days (MOD14C8H/MYD14C8H). Higher resolution 0.25
degree CMG fire products will eventually be produced as well. More information
can be found in the
MODIS
Collection 5 Active Fire Product User's Guide.
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Fire Pixel Locations vs.
Gridded Fire Products |
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We urge caution in using fire pixel locations in lieu of the 1-km gridded MODIS fire
products (CMG fire product). The former includes no information about cloud cover
or missing data and, depending on the sort of analysis that is being performed, it
is sometimes possible to derive misleading (or even incorrect) results by not
accounting for these other types of pixels. It is also possible to grossly misuse
fire pixel locations, even for regions and time periods in which cloud cover and
missing observations are negligible.
Some caveats to keep in mind when using MODIS fire pixel locations:
- The fire pixel location files allow users to temporally and spatially bin fire
counts arbitrarily. However, severe temporal and spatial biases may arise in any
MODIS fire time series analysis employing time intervals shorter than about eight
days.
- Known fires for which no entries occur in the fire-pixel location files are not
necessarily missed by the detection algorithm. Cloud obscuration, a lack of coverage,
or a misclassification in the land/sea mask may instead be responsible, but with only
the information provided in the fire location files this will be impossible to determine.
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Can I estimate burned area
using the active fire/hotspot data? |
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It is not recommended to use hotspot/active fire locations to estimate burned area
due to spatial and temporal sampling issues. Determining this to an acceptable degree
of accuracy is generally not possible due to nontrivial spatial and temporal sampling
issues. For some applications, however, acceptable accuracy can be achieved, although
the effective area burned per fire pixel is not simply a constant, but rather varies
with respect to several different vegetation and fire-related variables. See
Giglio et al. (2006)
for more information.
GFIMS provides monthly burned area images for visualization via
Web Fire
Mapper. Please refer to the following link for more information on the
MODIS Burned Area Product and
instructions on how download the HDF and GeoTIFF monthly burned area files.
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How often are the hotspot/fire
data acquired – what is the temporal resolution? |
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The MODIS instruments on board the Terra and Aqua EOS satellites acquire data continuously
providing global coverage every 1-2 days. As polar-orbiting spacecraft, Terra and
Aqua are synchronized with the sun, in order to pass over the same area at the same
time every day. Terra’s descending orbit (N-S) will cross the equator at 10:30 a.m.
local time during each orbit—hence the original term “AM.” in its formal name (EOS AM-1).
Clouds typically form over tropical land in the afternoon as the surface warms, creating
updrafts; hence, Terra’s morning view will provide clearer images of the Earth’s lands.
The satellite will orbit the Earth once every 99 minutes at an inclination of 98 degrees
relative to the equator, at a mean altitude of 438 nautical miles (705 kilometers). Aqua
(EOS PM-1) flies with similar characteristics, but with a “PM” equatorial crossing time
in an ascending orbit with a 1:30 p.m. equatorial crossing time, thus complementing and
extending the temporal resolution of the MODIS sensor. Terra and Aqua subsequently also
pass over the equator at around 10:30 pm and 1:30am, respectively.
For most parts of the Earth’s equator, therefore, there are 4 overpasses in a 24 hour
period (2 for Aqua and 2 for Terra – [Descending and ascending]). As the orbits of both
satellites “overlap” at the poles, there is more coverage per given area the further
north or south the area is from the equator. The precise number and timing of overpasses
depends therefore on your geographic location. See “What time does the satellite pass
over my area?.
For an artist’s visualization of “MODIS scans the globe” see:
http://aqua.nasa.gov/doc/viz/media/aqua_modis_soren.mov.
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What is the time delay between
satellite overpass and data provision on GFIMS? |
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The data feed from the MODIS sensors is continuous and at a download rate of +/- 1
terabyte per day. Thermal band information is received constantly from the ground
receiving stations and processed by MODIS Rapid Response at NASA as soon as it is received.
Data processed by MODIS Rapid Response are made available as active fire data on the
GFIMS website approximately 2 - 4 hours after local overpass. Occasionally, hardware
errors mean that it takes longer the 2-4 hours to process the data. For information
on the system status of MODIS Rapid Response, see:
http://rapidfire.sci.gsfc.nasa.gov/status/
Please refer to the data formats table for detailed information on when each GFIMS
service is updated.
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What are the attributes in
the hotspot/active fire data? |
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- Latitude and Longitude: The center point location of the 1km (approx.) pixel
flagged as containing one or more fires/hotspots (fire size is not 1km, but variable). See
What does a hotspot/fire detection mean on the ground?
- Brightness: The brightness temperature, measured (in Kelvin) using the MODIS
channels 21/22 and channel 31.
- Scan and Track: The actual spatial resolution of the scanned pixel. Although
the algorithm works at 1km resolution, the MODIS pixels get bigger toward the edge of the
scan. See What does scan and track mean?
- Date: Acquisition date of the hotspot/active fire pixel.
- Time: Time of the overpass of the satellite (in UTC).
- Satellite: Whether the detection was picked up by the Terra or Aqua satellite.
- Confidence: The detection confidence is a quality flag of the individual
hotspot/active fire pixel.
- Version: Version refers to the processing collection and source of data. The
number before the decimal refers to the collection (e.g. MODIS Collection 5). The number
after the decimal indicates the source of Level 1B data; data processed in near-real time
by MODIS Rapid Response will have the source code “CollectionNumber.0”. Data sourced from
MODAPS (with a 2 month lag) and processed by GFIMS using the standard MOD14/MYD14 Thermal
Anomalies algorithm will have a source code “CollectionNumber.x”. For example, data with
the version listed as 5.0 is collection 5, processed by MRR, data with the version listed
as 5.1 is collection 5 data processed by GFIMS using Level 1B data from MODAPS. See What
is the difference between data sourced from MODIS Rapid Response and MODAPS Collection 5?
- Bright.T31: Channel 31 brightness temperature (in Kelvins) of the hotspot/active
fire pixel.
- FRP: Fire Radiative Power. Depicts the pixel-integrated fire radiative power
in MW (MegaWatts). FRP provides information on the measured radiant heat output of detected
fires. The amount of radiant heat energy liberated per unit time (the Fire Radiative Power)
is thought to be related to the rate at which fuel is being consumed
(Wooster et. al. (2005))
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What is the brightness
temperature? |
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The brightness temperature of a hotspot/fire pixel is measured (in Kelvins) using
the MODIS channels 21/22 and channel 31. Brightness temperature is actually a measure
of the photons at a particular wavelength received by the spacecraft, but presented
in units of temperature.
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What does scan and track mean? |
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It should be noted that the pixel size is not always 1km across the scan track.
The pixels at the "Eastern" and the "Western" edges of the scan are bigger than 1km.
It is 1km only along the nadir (exact vertical from the satellite). Thus, the values
shown for scan and track represent the actual spatial resolution of the scanned pixel.
The scan value represents the spatial-resolution in the East-West direction of the scan
and the track value represents the North-South spatial resolution of the scan.
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What is the detection
confidence? |
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What are Collections? |
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Reprocessing of the entire MODIS data archive is periodically performed to incorporate
better calibration, algorithm refinements, and improved upstream products into all
MODIS products. The updated MODIS data archive resulting from each reprocessing is
referred to as a collection. Later collections supersede all earlier collections.
For the Terra MODIS, Collection 1 consists of the first products generated following
launch. Terra MODIS data were first reprocessed for the first time in June 2001 to
produce Collection 3. Note that this first reprocessing was numbered Collection 3,
rather than Collection 2, as one would expect. Collection 3 was also the first produced
for the Aqua MODIS products. Collection 4 reprocessing was initiated in December 2002
for the Terra MODIS, and somewhat later for the Aqua MODIS, and it forms the current
archive of the MODIS products. Collection 5 began reprocessing in early 2007, and it
forms the current archive of the MODIS products. Collection 6 is scheduled to begin
in 2011.
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What are the improvements
with Collection 5? |
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The detection confidence was improved to more accurately identify questionable
hotspot/active fire pixels (see: What is the detection confidence?). Fire Radiative
Power (FRP) value was also added (see: Fire Radiative Power).
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Are there any missing
MODIS fire/hotspot data? |
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In the Collection 5 fire data archive, there are several days where data was not
collected and days with lower than usual fire counts due to reasons such as sensor
outage. These include: 15 June - 3 July 2001; 19 - 28 March 2002; and 15 April 2001.
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Can you use the MODIS active
fire product for detecting volcanoes or volcanic eruptions? |
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The algorithm routinely detects active volcanoes but the active fire product has
not been validated against independent data for its ability to detect volcanoes.
There is a separate near-real time MODIS product specifically for volcanoes: MODVOLC.
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What validation of the MODIS
active fire products has been performed? |
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Validation of the Terra MODIS Fire Product has primarily been performed using coincident
observations from the Advanced Spaceborne Thermal Emission and Reflection Radiometer
(ASTER); see the
MODIS
Land Team Validation page, and publications by Csiszar et al.
(2006) and two publications from Morisette et al. (2005) for details. A very brief
discussion of the general validation procedure, with some preliminary results, can
be found in the Justice et al. (2002) publication.
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Where can I get more
information on the MODIS Fire Products? |
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For more information on the active hotspot/fire product and other MODIS fire products,
please refer to the
MODIS
Fire Product User's Guide, Version 2.4.
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What other types of hotspot/fire
data are available? |
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AVHRR: Advanced
Very High Resolution Radiometer.
AVHRR is a passive optical sensor that measures electromagnetic radiation (light reflected
and heat emitted) from our planet. AVHRR was originally intended only as a meteorological
satellite system but it does have applications for fire monitoring. AVHRR remotely senses
cloud cover and sea surface temperature, enabling its visible and infrared detectors to
observe trends in vegetation, clouds, shorelines, lakes, snow and ice. The visible bands
can detect smoke plumes from fires as well as burn scars. The thermal infrared band can
detect actual hotspots and active fires. Its ability to detect fires is greater at night,
since the system can confuse active fires with heated ground surfaces, such as beach sand and asphalt.
Active fire mapping on a global scale using a single satellite system has been coordinated
by the International Geosphere Biosphere Program (IGBP) using AVHRR data for 1992-93
from international ground stations.
In addition, a small number of countries have developed their own regional AVHRR
satellite fire monitoring systems using direct read-out; e.g., Brazil, Russia,
and Senegal. Research groups have provided regional examples of trace gas and particulate
emissions from fires for Brazil, Southern Africa and Alaska.
GOES: Geostationary
Operational Environmental Satellite.
The Geostationary Operational Environmental Satellites (GOES) house a five-channel
(one visible, four infrared) imaging radiometer designed to sense radiant and solar
reflected energy from sample areas of the Earth. They are stationed in orbits that
remain fixed over one spot on the equator, providing continuous coverage of one hemisphere.
GOES satellites acquire images every 15–30 minutes, at up to 1km resolution in visible
light, for the detection of smoke, and 4km resolution in thermal infrared to directly detect
the heat of fires.
MSG
SEVIRI: Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI).
The Meteosat Second Generation (MSG) satellite houses the optical imaging radiometer
called the Spinning Enhanced Visible and Infrared Imager (SEVIRI). The sensor features
12 spectral channels and will provide cloud imaging and tracking, fog detection, measurement
of the Earth surface and cloud top temperatures, tracking ozone patterns, as well as
active fire monitoring.
The nominal coverage of the satellite includes the whole of Europe, all of Africa and
locations at which the elevation to the satellite is greater than or equal to 10°. The
various channels provide measurements with a resolution of 3 km at the sub-satellite point.
The High Resolution Visible (HRV) channel provides measurements with a resolution of 1km.
The service, which commenced operations in January 2004, is due to continue until at least 2018.
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What is Web Fire Mapper? |
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Web Fire Mapper is an open source internet based mapping tool that delivers locations
of hotspots/fires. You can view an interactive map of the world showing hotspots/fires
for a specified time period, combined with a selection of GIS layers and satellite imagery.
Each hotspot/active fire location represents the center of a 1km (approx.) pixel
flagged as containing one or more actively burning hotspots/fires within that pixel.
The hotspots/fires are detected using data from the MODIS (or Moderate Resolution
Imaging Spectroradiometer) instrument, on board NASA's Aqua and Terra satellites.
|
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Why can't I open Web Fire
Mapper in my browser? |
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If you are having trouble accessing Web Fire Mapper, your Internet Service Provider
or organization may be blocking port 8080. Web Fire Mapper runs on port 8080 and
blocking this port will effectively prevent the service from loading in your browser.
Please contact your network administrator to remedy the situation. However, if you
have determined that port 8080 is NOT blocked on your end, the WFM service may be
experiencing technical interruptions. Please contact us at
gfims@fao.org and let us
know about this issue.
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When trying to access Web Fire
Mapper, I get an error that reads "Service not available. Please try again". What does this
mean? |
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The "Service not available" message is displayed in the event there is an error with
the internal workings (e.g. database) of the Web Fire Mapper system. Please wait
for a few minutes and try to refresh the page (Ctrl + F5). If you still get the error,
please contact GFIMS at gfims@fao.org.
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What open source components
are used in Web Fire Mapper? |
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The Web Fire Mapper was developed using Open Source web-GIS technologies, including
UMN Mapserver, Google Web Toolkit, PHP and PostgreSQL with the spatial database add-on,
PostGIS. The Servers utilized at the University of Maryland have Linux operating
systems and Apache/Tomcat web-servers, making the entire system completely based on
free and open source software.
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Can I download the hotspot/fire
data from Web Fire Mapper? |
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Hotspot/active fire data are not currently available for download via Web Fire Mapper.
However, hotspot/active fire locations are available in text file format from the ftp
site and as shape and KML files at the Active Fire Data section in the GFIMS website.
The text files provide data for the last 2 months; the shape files provide data for
the last 24 hours, last 48 hours and last 7 days for download.
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Can I get information on
burned areas from Web Fire Mapper? |
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GFIMS currently offers visualization of monthly burned area images in Web Fire Mapper.
Please refer to the following link for background information on MODIS burned area
images in Web Fire Mapper. For more information regarding the MODIS Burned Area Product,
please refer to this link on the GFIMS website.
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What is the difference between
the data sourced from MODIS Rapid Response and MODAPS Collection 5? |
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There are 3 key differences between data processed by MODIS Rapid Response (MRR) and
MODIS Data Processing System (MODAPS). The first is the time taken to process the data:
data from MRR are processed in near-real time (approx 2-4 hours after satellite overpass),
while data from MODAPS will generally available after a two month lag. The second is the
"quality assurance" of Level 1B data used to generate the fire product - data from MODAPS
are quality checked, and sometimes reprocessed at a later date if some problems are found
with specific granules (the reason for the 2 month lag in making the collection from
MODAPS available via GFIMS is to allow for any reprocessing of granules before the fire
product is generated). The third reason is that MODAPS Aqua data are processed with the
definitive ephemeris downloaded from the satellite (this provides the actual location of
the satellite, which in turn affects the geolocational accuracy of the MODIS granules).
Aqua data processed by MRR uses a predicted ephemeris (updated daily using definitive data).
The difference in geolocations from the definitive and predicted is checked daily by the
MRR system. The difference is usually in the range of 50-100m. In cases where it exceeds
400m (only happens during certain spacecraft manoeuvres), affected MRR data are reprocessed
with the definitive data the next day. Users are encouraged to use MODAPS collection 5 for
any historical analysis.
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What are the known issues
with Web Fire Mapper? |
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November 2009: Fire density grid does not operate as expected.
The Web Fire Mapper (WFM) allows users to view historical fire data by entering
custom dates. If the query returns a large number of fire points, WFM displays an
aggregate summary of fires by displaying a fire density grid. This grid provides
an overview of the density of fires in a given area rather than individual fire
locations, thereby avoiding the need to query large number of fires from the server.
To display the fire density grid, WFM uses certain pre-calculated summaries where
fire points are aggregated into specific spatial and temporal intervals. Having fire
data aggregated at fixed intervals means that when a user enters a custom date range
it may not match the fixed interval date range of the fires calculated for the grid
displayed. As a result, the grid may include summaries of fire points beyond the
user-entered date range. This system flaw is currently being addressed and is a priority
in the ongoing update of the GFIMS system.
In the interim, when a fire aggregate grid is displayed, please zoom in further until
you see individual fire points. As long as the total number of fires being queried
is relatively small for smaller spatial extents, the user query will be returned
correctly as fire points instead of the fire density grid.
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Can you notify me when a
hotspot/fire occurs in my area of interest? |
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We have developed a global hotspot/fire alert system to notify users when a hotspot/fire
occurs in, or near, a specified area of interest, country or protected area. You can
subscribe to receive near-real time, daily or weekly alerts in English, French or Spanish.
Click here to subscribe,
or learn more about the email based alert system.
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Do you provide mobile/cell
phone text messages? |
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No, we do not currently provide SMS text messages. In the past, we helped develop
such a service in collaboration with ESKOM and CSIR Meraka in South Africa for the
protection of power lines in remote areas from wildfires informing operators in the
field about fire events in near-real time (Davies et al. (2008)).
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What are the near-real time
email alerts? |
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The near-real time alerts provide fire locations of fires that have occurred in your
area of interest 2 - 4 hours after satellite overpass. They are subscribed to
and managed by the user just the same way as the daily and weekly detection summaries,
but the near-real time alerts are actually mailed to you directly from
MODIS Rapid Response
to minimize the temporal detection-to-inbox lag time.
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Why do I receive more than
one near-real time alert in a short period of time? |
|
The MODIS sensor is on board two satellites, Terra and Aqua. Each satellite generally
makes at least 2 daily overpasses over every area on the earth's equator (and many
more towards the poles). The sensor images the earth in 2330 km swaths, therefore if
you subscribed to a large area, like the USA, you will receive multiple near-real
time email alerts for a given overpass (e.g. Terra daytime overpass) as it takes
several swaths to cover the whole of the US.
For an artist's visualization of "MODIS scans the globe" go to:
Higher resolution movie files can be found at:
To determine where and when the overpass is going to occur, you may refer to the Terra
and Aqua Orbit Tracks from the following websites:
The maps show a series of white lines with tic marks showing what time the satellite
will pass over a certain location on the Earth. The white lines represent the center
of the swath and the tic marks and time show at what time in UTC the satellite has
passed over that location. Please refer to the
MODIS RR FAQ
for more information.
If you wish to view the MODIS near-real time swath image that corresponds to the
active fire detections, please go to the following website:
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How do I subscribe or
edit email alerts? |
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- Go to GFIMS
Fire Email Alerts Home
- Enter the email address where you want to receive the email alerts and click "Proceed".
- If you have not yet subscribed you will be asked to enter your Name, Organization,
and Country. Click on "Save" after you have entered your information.
- You will be taken to the subscription summary page, where the user can create a new
subscription or view the existing ones.
- The user can create several subscriptions, and they will be added to his/her subscription
summary profile.
- Clicking on the "Create a New Subscription" link takes the user to the interface to
subscribe to an email alert.
Creating a new subscription:
- Choose your area of interest: The user can choose to select an area from a map (by
defining a rectangular area), from a political boundary drop down list or a drop down
list of protected areas.
- Customize your email alert by changing your subscription preferences:
- Name your alert (optional): The user can choose to give your alert a name
for you to easily reference.
- Output map size: The user may choose to receive a map in the email and different
sized maps are available.
- Background image: This refers to the background image on which the fires will
be overlaid in the map in the email.
- Language preference: Currently only in English and Spanish, this will be expanded
initially to French, as part of FAO agreements.
- Alert type: Daily, Weekly or Near-Real Time:
- Daily: All the received MODIS Rapid Response fire hotspots are sent in a
summary email every morning ET (USA) with fire detections from the previous
24 hours.
- Weekly: A week's worth of fire points detected for the specified area are
sent to the user on Monday mornings ET (USA).
- Near-real time: The fire points are sent out in an email as soon as they
are processed by MODIS Rapid Response (approximately 2-4 hours after satellite
overpass). The number of email varies depending on whether or not there was a
fire in the specified area, whether or not it was detected, and the geographical
location of the area (there are more frequent overpasses at high latitudes, and 4
daily overpasses for most places on the equator).
- Email preferences: The user can choose to receive an email with a map and text, or
text only.
- Attach .CSV file: By default this option is flagged, meaning that the subscriber will
also receive a CSV file containing the fire hotspots information.
- Help with subscription preferences: Clicking on the hyperlinked text of the subscription
preferences will open pop-up messages containing the description and usage of the preference.
- Email confirmation and final subscription: The user can choose not to receive an email
confirming that he/she has subscribed successfully to an alert. The final signoff is completed
by clicking either "Subscribe" or "Cancel" (deletes all selections).
Subscription confirmations:
- The successful subscription is identified by two steps, the first of which is
the confirmation page and a confirmation email (if this was selected).
- The confirmation page provides a link to let you return to the 'add, view or
edit your subscription' page.
For more details on the subscription tasks, refer to the
User Guide.
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My email has changed,
how do I change it? |
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- Go to: GFIMS
Fire Email Alerts Home
- Enter the email address where you currently receive email alerts and click "Proceed".
- You will be taken to the Subscription Summary page where you can edit your information.
- Click on "Edit" in the Your Information box.
- Here you can change your email address to the new address where you would like the
email alerts sent.
- Click "Save" to save the changes you made to your information.
For more details on this task, refer to the
User Guide.
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I can't see the administrative
boundaries, where are they? |
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In order to see the administrative boundaries on the email alerts system, visit the
GFIMS
Fire Email Alerts page and log in with your email address.
Once you have logged in, proceed to the subscriptions page by either creating a
new subscription or by editing one of your existing subscriptions. Then, choose the
interactive map option, and zoom in using the zoom-in tool provided. Once you zoom
in considerably to an area, you should be able to see the administrative boundaries.
For more details on this task, refer to the
User Guide.
|
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I have received a CSV file
as part of my Email Alert, how do I add it as a layer in a Desktop GIS software? |
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A CSV or Comma Separated Value file, is a text file in which separate fields are delimited
by commas. This type of file can be used to store simple tabular data efficiently,
minimizing file size. CSV files are easily opened with DB administration software
such as PostgreSQL or MS Access, or by spreadsheet software such as MS Excel. This
type of file can also be used to easily plot point data on desktop GIS software,
given, as the active fire data does, that the tabular data contains X and Y coordinate
information. The active fire data contains latitude and longitude location coordinates
and the attributes of the detected hotspots.
An example of plotting the fire points using ESRI ArcGIS 9.X ArcMap:
- Open ArcMap and go to 'Tools' on the Main Menu
- Select 'Add XY Data'
- Navigate to the location of your CSV file and select the file
- It should automatically select:
- X Field: Longitude
- Y Field: Latitude
- Then you should select the Coordinate System
- Click 'Edit...' then the 'Spatial Reference Properties' window will open
- Click on 'Select'
- Select 'Geographic Coordinate System' > 'World' > 'WGS 1984'
- Click Add and click OK
- To permanently save your hotspots/fires layer as a shapefile:
- Right-click on the layer
- Select 'Data' > 'Export Data' and enter the file name with the .shp extension
- Click OK.
* Please note: ArcMap does NOT honor the time values in the CSV file and will default
the time values to 12:00:00 AM. If you need the time values intact, please export
the CSV file to a personal geodatabase.
An example of plotting the fire points using ESRI ArcView 3.X:
- Re-name the extension of the CSV file to .txt
- Open ArcView
- Click on 'Tables' in the Project window and select 'Add'
- Change 'List Files of Type' to 'Delimited Text (*.txt)' and navigate to the .txt file, select and click OK
- Select the View window
- Go to 'View' on the Main Menu > 'Add Event Theme'
- The Add Event Theme window will open with the following automatically selected:
- Table: The .txt file that you selected
- X Field: Longitude
- Y field: Latitude
- Click OK and your hotspot/fire points will show up in the View window
- To permanently save your hotspot/fire locations as a shapefile:
- Select the fire points theme in the View window
- Go to 'Theme' on the Main Menu > 'Convert to Shapefile...'
- Give it a file name with .shp extension
- Click OK.
* Please note: ArcView WILL honor the time values in the CSV files.
|
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Available Data Formats for hotspot/fire information |
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Data |
Type |
Description |
Coverage |
Projection |
Update frequency |
Active Fire Text Files(.txt) |
Daily Text files for the last 2 months |
Location coordinates of the center point of 1km (approx.) fire pixel detected |
Global and regional* |
Geographic, WGS 1984 |
Near-real time updates. Text files are pushed from MODIS Rapid Response as they are processed from Level 2 data. |
Active Fire Shapefiles(.shp) |
Last 24 hours
Last 48 hours
Last 7 days |
Point (Center point of 1km fire pixel detected) |
Global |
Geographic, WGS 1984 |
Updated every hour, starting at 00:42 ET (USA) |
Web Fire Mapper |
Last 24, hours, 48 hours, 72 hours, last 7 days, and previous years |
Interactive web fire map of the world. Data not yet downloadable. |
Global |
Geographic, WGS 1984 |
Updated every hour, starting 00:00 ET (USA) |
KML (.kml)(.kml) |
Last 24 hours last 48 hours |
Center point of 1km (approx.) fire pixel detected |
Global and regional* |
Geographic, WGS 1984 |
Updated every hour, starting 00:42 ET (USA) |
Web Map Services (WMS version 1.1.1) (WMS version 1.1.1) |
Last 24 hours Last 48 hours |
Allow local (desktop) or web GIS clients to access the Web Fire Mapper data without accessing website |
Global and regional* |
Geographic, WGS 1984 |
Same as Web Fire Mapper |
Near-real time, daily and weekly Email Alerts (email, .csv) |
Near-real time Last 24 hours Past week |
Near-real time, daily and weekly email alerts of fires |
Select area using map, or from list of countries and protected areas |
Geographic, WGS 1894 |
Sent out starting at 04:30 ET (USA) |
MODIS Image Subsets (.jpg or .tif) |
Daily near-real time in various resolutions 4km, 2km, 1km, 500m, and 250m |
Images of certain regions of the world overlaid with red polygon outline of 1km fire pixel detected |
Select regions of the world |
Plate Caree |
Updated in near-real time from MODIS Rapid Response System. |
* Regional datasets include: Australia and New Zealand, Alaska, Canada, North,
Central and South America, Northern, Central and Southern Africa, Mozambique, Namibia,
Europe, Russia, Asia, South and South East Asia.
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| TXT FILES: |
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How do I register
to receive active fire/hotspot text files? |
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There is no charge to access the hotspot/ active fire text files for the last 2
months; but we would like to keep track of who accesses the FTP site and keep you
up to dated with changes made to the site. Please email
us the following information:
- Name, Organization, Address, Country and Email
Please also state:
- How often you access the site (i) daily, (ii) weekly, (iii) monthly OR (iv) occasionally?
- What do you use the data for?
- What is your region of interest?
You will be sent an email with a user name and password to enable you to access the FTP site.
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| SHAPE FILES: |
 |
How do I use them? |
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A shapefile is a proprietary file format of ESRI. Shapefiles have de facto become a
standard for the storage of vector geometry information and associated attribute
information to be used in desktop GIS applications. This file format is composed by
a minimum of three files, a .shp .shx and .dbf files which need to be kept together
in the same directory for the file to be opened by GIS software. A shapefile can be
opened and visualized by the vast majority of GIS software, including ESRI ArcGIS
and free and open source software such as Quantum GIS.
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| KML: |
 |
How do I view the KML
in Google Earth? |
|
Once you have installed Google Earth on your computer, you can view the KML in Google Earth.
- First, download the KML from the KML download page to a location on your computer.
- Then, double-click the file. This will launch Google Earth and open the hotspots/fire
points in the Temporary Places location.
Alternatively, open Google Earth, go to File… then navigate to the location of the KML
on your computer and open the file.
|
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Things to be aware of when
viewing MODIS active fire data in Google Earth |
|
When viewing GFIMS hotspot/fire data in Google Earth you need to bear in mind that
the GFIMS data will remain at 1km (approx.) resolution whereas the spatial resolution
of the imagery in Google Earth will change as you zoom in. This is important to remember
as when zoomed in the actual location of a hotspot/fire will not exactly where the
fire icon is but rather anywhere within an approximate 1km pixel centering on the icon.
|
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The KML in Google Earth shows
a hotspot/fire in a park nearby, but I did not see that fire. Is it a real fire? |
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This may be because you are viewing the 1km (approx.) hotspot/fire data on imagery that has
much higher spatial resolution (at least 30m), such as the imagery provided in Google
Earth. As explained earlier (What does a hotspot/fire detection mean on the ground?),
the coordinates of a fire/hotspot are given as the centre of an approximate 1km pixel.
In actual fact, one or more hotspots/fires can occur anywhere within the 1km (approx.)
pixel. When viewing higher resolution imagery it is easy to 'see' the fire location as
being inside a boundary, or on one side of the road - but it is important to remember
the location you see when zoomed into the imagery is the centre of the 1km fire pixel
and the fire could have actually occurred anywhere within that 1km pixel.
In the image below, the zoom is centred on the fire hotspot icon in the middle of
the window. The actual fire could be anywhere in an area of 1km x 1km centred on that
icon. The size of the fire is also variable depending on many factors.

|
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What is the KML Time series? |
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The MODIS KML time series is an experimental product that shows hotspot/active fire
detections by animating the location of fires that have occurred in the region in
the last 48 hours. The Time Series should be used with caution, taking into mind
the caveats and issues with the temporal and spatial resolution of the MODIS fire
pixel locations.
|
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Why can't I see all
the fire points in Google Maps? |
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If you are using Google Maps to view the GFIMS KML, you may not be able to view all
of the fire points. This is due to the size and complexity
restrictions
Google imposes on KML rendering within Google Maps. We recommend using Google Earth
for viewing GFIMS KML files.
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| Web Map Services (WMS): |
 |
How do I view the WMS? |
|
The Web Fire Mapper
WMS (version 1.1.1) offers Open GIS Consortium standard Web Map Service interface.
Using the Web Fire Mapper, you can allow your local (desktop) or web GIS clients to
access the data without accessing the Web Fire Mapper Website.
The two WMS requests currently available here are (i) the GetMap request, and (ii) the
GetCapabilities request. Click on these links to obtain the corresponding result.
If you want the request URLs, click on "Show URL" link and copy-paste the required
URL into your desired GIS client.
If you want more information about the OpenGIS WMS specification, click
here.
For help with customizing the requests, read ESRI
WMS
and WFS Connector help.
|
| NASA WorldWind: |
 |
How do I view the NASA
WorldWind Plugin? ? |
|
GFIMS provides a plugin for NASA World Wind to display hotspot/ active fire detections
for the last 48 hours for most of the globe.
NASA World Wind can be downloaded from:
Installation:
- Extract the zip file and copy the gfims-wms XML document and the fires.png file
to:($installation directory)\Config\Earth
- For example, in Windows, the default path set for NASA World Wind Version 1.4 is:
C:\Program Files\NASA\World Wind 1.4\Config\Earth
- Open NASA World Wind and click on the "GFIMS Hotspots - Past 48 Hours" icon in the
tool bar to see the active fire/hotspot detections.
|
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What is an image subset? |
|
An image subset is an image created by the MODIS Rapid Response team for a specific
area of the globe. These images are available as true color composites as well as
other band visualizations and ratios which illustrate different land characteristics.
The images can be overlaid on the MODIS Rapid Response website with vector information
such as fires detected and political boundaries, and can be downloaded as GeoTIFFs
or JPEGs with associated world files containing the georeferencing information for
loading into GIS software. Metadata are also available.
Subsets are available at:
|
 |
Can I get an image subset for
my area of interest? |
|
Please let us know if you are interested in setting up a MODIS image subset for the area
you are interested in. Our objective is to provide users with a quick overview of their
area. The JPEG or GeoTIFF images are kept small to enable users with slow or limited
Internet access to still get the data. By improving access to these MODIS images we hope
to enhance the capabilities of protected area managers to monitor fires and determine
the extent of burn.
|
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What other products are available? |
|
GFIMS provides yearly global animations of monthly Terra hotspot/active fire pixel
locations. The global animation is created from monthly subsets to provide a
synopsis of the burning pattern. The global animation cycles through an entire year
to show the spatial and temporal variation of the burning in different parts of the
world. These images help provide an understanding of the global pattern of hotspots/active
fires. All these images can be accessed from the Resources page.
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