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Wikipedia / Moderate Resolution Imaging Spectroradiometer

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. Since 2011, MODIS operations have been supplemented by VIIRS sensors, such as the one aboard Suomi NPP. The systems often conduct similar operations due to their similar designs and orbits (with VIIRS data systems designed to be compatible with MODIS), though they have subtle differences contributing to similar but not identical uses.

The MODIS instruments were built by Santa Barbara Remote Sensing. They capture data in 36 spectral bands ranging in wavelength from 0.4 μm to 14.4μm and at varying spatial resolutions (2 bands at 250 m, 5 bands at 500 m and 29 bands at 1km). 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, radiation budget and processes occurring in the oceans, on land, and in the lower atmosphere.

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 Aral Sea, and the detection and mapping of wildland fires 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.

Specifications

Specifications

Orbit

705km, 10:30a.m. descending node (Terra) or 1:30p.m. ascending node (Aqua), Sun-synchronous, near-polar, circular

Scan rate

20.3 rpm, cross track

Swath

2330km (cross track) by 10km (along track at nadir)

Dimensions

Telescope

17.78cm diam. off-axis, afocal (collimated), with intermediate field stop

Size

1.0 × 1.6 × 1.0 m

Weight

228.7kg

Power

162.5 W (single orbit average)

Data rate

10.6 Mbit/s (peak daytime); 6.1Mbit/s (orbital average)

Quantization

12 bits

Spatial resolution

250 m (bands 1–2) 500 m (bands 3–7) 1000 m (bands 8–36)

Temporal resolution

1–2 days

Design life

6 years

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

Band

Wavelength(nm)

Resolution(m)

Primary use

1

620–670

250

Land/cloud/aerosolsboundaries

2

841–876

250

3

459–479

500

Land/cloud/aerosolsproperties

4

545–565

500

5

1230–1250

500

6

1628–1652

500

7

2105–2155

500

8

405–420

1000

Ocean color/phytoplankton/biogeochemistry

9

438–448

1000

10

483–493

1000

11

526–536

1000

12

546–556

1000

13

662–672

1000

14

673–683

1000

15

743–753

1000

16

862–877

1000

17

890–920

1000

Atmosphericwater vapor

18

931–941

1000

19

915–965

1000

Band

Wavelength(μm)

Resolution(m)

Primary use

20

3.660–3.840

1000

Surface/cloudtemperature

21

3.929–3.989

1000

22

3.929–3.989

1000

23

4.020–4.080

1000

24

4.433–4.498

1000

Atmospherictemperature

25

4.482–4.549

1000

26

1.360–1.390

1000

Cirrus cloudswater vapor

27

6.535–6.895

1000

28

7.175–7.475

1000

29

8.400–8.700

1000

Cloud properties

30

9.580–9.880

1000

Ozone

31

10.780–11.280

1000

Surface/cloudtemperature

32

11.770–12.270

1000

33

13.185–13.485

1000

Cloud topaltitude

34

13.485–13.785

1000

35

13.785–14.085

1000

36

14.085–14.385

1000

MODIS data

MODIS Level 3 datasets

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

Daily

8-day

16-day

32-day

Monthly

Yearly

Grid

Platform

Description

MxD08_D3

MxD08_E3

—

—

MxD08_M3

—

1° CMG

Terra, Aqua

Aerosol, cloud water vapor, ozone

MxD10A1

MxD10A2

—

—

—

—

500m SIN

Terra, Aqua

Snow cover

MxD11A1

MxD11A2

—

—

—

—

1000m SIN

Terra, Aqua

Land surface temperature/emissivity

MxD11B1

—

—

—

—

—

6000m SIN

Terra, Aqua

Land surface temperature/emissivity

MxD11C1

MxD11C2

—

—

MxD11C3

—

0.05° CMG

Terra, Aqua

Land surface temperature/emissivity

—

—

MxD13C1

—

MxD13C2

—

0.05° CMG

Terra, Aqua

Vegetation indices

MxD14A1

MxD14A2

—

—

—

—

1000m SIN

Terra, Aqua

Thermal anomalies, fire

—

—

—

—

MCD45A1

—

500m SIN

Terra+Aqua

Burned area

250m SIN

500m SIN

1000m SIN

0.05° CMG

1° CMG

Time window

Platform

Description

MxD09Q1

MxD09A1

—

—

—

8-day

Terra, Aqua

Surface reflectance

—

—

—

MxD09CMG

—

Daily

Terra, Aqua

Surface reflectance

—

MCD12Q1

—

MCD12C1

—

Yearly

Terra+Aqua

Land cover type

—

MCD12Q2

—

—

—

Yearly

Terra+Aqua

Land cover dynamics

(global vegetation phenology)

MxD13Q1

MxD13A1

MxD13A2

MxD13C1

—

16-day

Terra, Aqua

Vegetation indices

—

—

MxD13A3

MxD13C2

—

Monthly

Terra, Aqua

Vegetation indices

—

MCD43A1

MCD43B1

MCD43C1

—

16-day

Terra+Aqua

BRDF/albedo model parameters

—

MCD43A3

MCD43B3

MCD43C3

—

16-day

Terra+Aqua

Albedo

—

MCD43A4

MCD43B4

MCD43C4

—

16-day

Terra+Aqua

Nadir BRDF-adjusted reflectance

See also

References

Modis has 36 spectral bands