The Moderate Resolution Imaging Spectroradiometer (MODIS) is a satellite-based sensor used for earth and climate measurements. There are two MODIS sensors in Earth orbit: one on board the Terra ( EOS AM) satellite, launched by NASA in 1999; and one on board the Aqua (EOS PM) satellite, launched in 2002. MODIS has now been replaced by the VIIRS, which first launched in 2011 aboard the Suomi NPP satellite. The MODIS instruments were built by Santa Barbara Remote Sensing. They capture data in 36 spectral bands ranging in wavelength from 0.4

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

to 14.4 μm and at varying spatial resolutions (2 bands at 250 m, 5 bands at 500 m and 29 bands at 1 km). Together the instruments image the entire Earth every 1 to 2 days. They are designed to provide measurements in large-scale global dynamics including changes in Earth's

cloud cover Cloud cover (also known as cloudiness, cloudage, or cloud amount) refers to the fraction of the sky obscured by clouds on average when observed from a particular location. Okta is the usual unit for measurement of the cloud cover. The cloud co ...

radiation budget Earth's energy budget accounts for the balance between the energy that Earth receives from the Sun and the energy the Earth loses back into outer space. Smaller energy sources, such as Earth's internal heat, are taken into consideration, but m ...

and processes occurring in the oceans, on land, and in the

lower atmosphere Lower atmosphere is a collective term sometimes used to refer to various layers of the atmosphere of the Earth and corresponding regions of the atmospheres of other planets, and includes: * The troposphere The troposphere is the first and lowest ...

. Support and calibration is provided by the MODIS characterization support team (MCST).

Applications

With its high temporal resolution although low spatial resolution, MODIS data are useful to track changes in the landscape over time. Examples of such applications are the monitoring of vegetation health by means of time-series analyses with vegetation indices, long term land cover changes (e.g. to monitor deforestation rates), global snow cover trends, water inundation from pluvial, riverine, or sea level rise flooding in coastal areas, change of water levels of major lakes such as the

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, and the detection and mapping of

wildland fires A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...

in the United States. The United States Forest Service's Remote Sensing Applications Center analyzes MODIS imagery on a continuous basis to provide information for the management and suppression of wildfires."MODIS Active Fire Mapping Program FAQs."
''United States Forest Service.'' Retrieved: 30 September 2014.

Specifications

Calibration

MODIS utilizes four on-board calibrators in addition to the space view in order to provide in-flight calibration: solar diffuser (SD), solar diffuser stability monitor (SDSM), spectral radiometric calibration assembly (SRCA), and a v-groove black body. MODIS has used the marine optical buoy for vicarious calibration.

MODIS bands

MODIS data

MODIS Level 3 datasets

The following MODIS Level 3 (L3) datasets are available from NASA, as processed by the Collection 5 software.

Availability

Raw MODIS data stream can be received in real-time using a tracking antenna, due to the instrument's direct broadcast capability. Alternatively, the scientific data are made available to the public via several World Wide Web sites and FTP archives, such as:
ECHO Reverb
– the next generation metadata and service discovery tool, which has replaced the former Warehouse Inventory and Search Tool (WIST);
LAADS Web
– Level 1 and Atmosphere Archive and Distribution System (LAADS) web interface;
LANCE-MODIS
– Land Atmosphere Near real-time Capability for EOS * ftp://ladsftp.nascom.nasa.gov/ – LAADS underlying FTP server; * http://e4ftl01.cr.usgs.gov/ – Earth land surface datasets; * ftp://n4ftl01u.ecs.nasa.gov/ – snow and ice datasets. Most of the data are available in the HDF-EOS format — a variant of Hierarchical Data Format prescribed for the data derived from Earth Observing System missions.

References

External links

Official NASA siteMODIS bands and spectral ranges (broken link)MODIS Images of the Day

– Google Gadget referring to MODIS image of the day.
Gallery of Images of Interest
* ttp://rapidfire.sci.gsfc.nasa.gov/ MODIS Rapid Response system (near real time images)br>NASA OnEarth (Web service for MODIS imagery)Visible Earth: Latest MODIS imagesMODIS Sinusoidal: Projection 6842 – MODIS SinusoidalPython: accessing near real-time MODIS images and fire data from NASA’s Aqua and Terra satellites
( Python) {{Authority control Satellite imaging sensors NASA