MODIS/Terra Calibrated Radiances 5-Min L1B Swath 1km (MOD021KM, Collection 004 and 005)
Entry ID: MOD021KM

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Summary
Abstract: The MODIS Level 1B data set contains calibrated and geolocated
at-aperture radiances for 36 discrete bands located in the 0.4 to 14.4
micron region of electromagentic spectrum. These data are generated
from the MODIS Level 1A scans of raw radiance and in the process
converted to geophysical units of W/(m^2 um sr). In addition, the
Earth Bi-directional Reflectance Distribution Function (BRDF) may be
determined for the solar reflective bands (1-19, 26) through knowledge
of the solar irradiance (e.g., determined from MODIS solar diffuser
data, and from the target illumination geometry). Additional data are
provided including quality flags, error estimates and calibration
data.

Visible, shortwave infrared, and near infrared measurements are only
made during the daytime, while radiances for the thermal infrared
region (bands 20-25, 27-36) are measured continuously.

Channel locations for MODIS are as follows:

Band Center Wavelength (um) Primary Use
---- ---------------------- -----------
1 0.620 - 0.670 Land/Cloud Boundaries
2 0.841 - 0.876 Land/Cloud Boundaries
3 0.459 - 0.479 Land/Cloud Properties
4 0.545 - 0.565 Land/Cloud Properties
5 1.230 - 1.250 Land/Cloud Properties
6 1.628 - 1.652 Land/Cloud Properties
7 2.105 - 2.155 Land/Cloud Properties
8 0.405 - 0.420 Ocean Color/Phytoplankton
9 0.438 - 0.448 Ocean Color/Phytoplankton
10 0.483 - 0.493 Ocean Color/Phytoplankton
11 0.526 - 0.536 Ocean Color/Phytoplankton
12 0.546 - 0.556 Ocean Color/Phytoplankton
13 0.662 - 0.672 Ocean Color/Phytoplankton
14 0.673 - 0.683 Ocean Color/Phytoplankton
15 0.743 - 0.753 Ocean Color/Phytoplankton
16 0.862 - 0.877 Ocean Color/Phytoplankton
17 0.890 - 0.920 Atmospheric Water Vapor
18 0.931 - 0.941 Atmospheric Water Vapor
19 0.915 - 0.965 Atmospheric Water Vapor
20 3.660 - 3.840 Surface/Cloud Temperature
21 3.929 - 3.989 Surface/Cloud Temperature
22 3.929 - 3.989 Surface/Cloud Temperature
23 4.020 - 4.080 Surface/Cloud Temperature
24 4.433 - 4.498 Atmospheric Temperature
25 4.482 - 4.549 Atmospheric Temperature
26 1.360 - 1.390 Cirrus Clouds
27 6.535 - 6.895 Water Vapor Profile
28 7.175 - 7.475 Water Vapor Profile
29 8.400 - 8.700 Water Vapor Profile
30 9.580 - 9.880 Ozone Overburden
31 10.780 - 11.280 Surface/Cloud Temperature
32 11.770 - 12.270 Surface/Cloud Temperature
33 13.185 - 13.485 Cloud Top Altitude
34 13.485 - 13.785 Cloud Top Altitude
35 13.785 - 14.085 Cloud Top Altitude
36 14.085 - 14.385 Cloud Top Altitude

Channels 1 and 2 have 250 m resolution, channels 3 through 7 have 500
m resolution, and the rest have 1 km resolution. However, for the
MODIS L1B 1 km product, the 250 m and 500 m band radiance data and
their associated uncertainties have been aggregated to 1 km
resolution. Thus the entire channel data set is referenced to the same
spatial and geolocation scales. Separate L1B products are available
for the 250 m channels (MOD02QKM) and 500 m channels (MOD02HKM) that
preserve the original resolution of the data.

Spatial resolution for pixels at nadir is 1 km, degrading to 4.8 km in
the along-scan direction at the scan extremes. However, thanks to the
overlapping of consecutive swaths and respectively pixels there, the
resulting resolution at the scan extremes is about 2 km. A 55 degree
scanning pattern at the EOS orbit of 705 km results in a 2330 km
orbital swath width and provides global coverage every one to two
days. A single MODIS Level 1B granule will nominally contain a scene
built from 203 scans (or swaths) sampled 1354 times in the cross-track
direction, corresponding to approximately 5 minutes worth of data.
Since an individual MODIS scan (or swath) will contain 10 along-track
spatial elements, the scene will be composed of (1354 x 2030) pixels,
resulting in a spatial coverage of (2330 km x 2030 km).Due to the
MODIS scan geometry, there will be increasing overlap occurring beyond
about 25 degrees scan angle.

To summarize, the MODIS L1B 1 km data product consists of:

1. Calibrated radiances and uncertainties for (2) 250 m reflected
solar bands aggregated to 1 km resolution

2. Calibrated radiances and uncertainties for (5) 500 m reflected
solar bands aggregated to 1 km resolution

3. Calibrated radiances and uncertainties for (13) 1 km reflected
solar bands and (16) infrared emissive bands

4. Geolocation subsampled at every 5th pixel across and along track

5. Satellite and solar angles subsampled at the above frequency

6. Comprehensive set of file-level metadata summarizing the spatial,
temporal and parameter attributes of the data, as well as auxiliary
information pertaining to instrument status and data quality
characterization

Users requiring the full-resolution geolocation and solar/satellite
geometry can obtain the separate MODIS Level 1 Geolocation product
(MOD03) from LAADS.

The MODIS L1B data are stored in the Earth Observing System
Hierarchical Data Format (HDF-EOS) which is an extension of HDF as
developed by the National Center for Supercomputer Applications (NCSA)
at the University of Illinois. A typical file size will be
approximately 260 MB.

Environmental information derived from MODIS L1B measurements will
offer a comprehensive and unprecedented look at terrestrial,
atmospheric, and ocean phenomenology for a wide and diverse community
of users throughout the world.

(The Shortname for this product is MOD021KM)

The V004 Program Executable (PGE), for MODIS Level 1B products, has
gone through a series of revisions since the initial release of V4.0.0
in March of 2002. These include revisions to make it
LINUX-compatible. The current version is V4.0.9, which does not
contain changes to the code that affect scientific output.

Below is a brief overview of changes that affect scientific output in
previous versions (V4.0.0 to V4.0.7) of PGE code. The MCST web site,
listed in the URL section of this DIF, has a more detailed version of
this information, including revisions that do not affect scientific
output.

Significant changes to Look Up Tables (LUT) used in Level 1B
processing have occurred. These include revising the
Response-versus-Scan Angle (RVS) LUTs from listing the RVS corrections
to listing the quadratic coefficients used in making the RVS
correction. The coefficients are now calculated by interpolating on
the granule collection time and the RVS corrections are then generated
using the interpolated coefficients. Previously used Emissive and
Reflective RVS LUT tables were eliminated and new ones introduced.

An incorrect comparison between RVS coefficients for Thermal
Emissivity Bands (TEB) and Reflective Solar Bands (RSB) was being made
during the calculation of the RVS coefficients. This was replaced with
a comparison between TEB coefficients. This error never resulted in
an incorrect RVS correction but did lead to re-calculating the
coefficients for each detector in a thermal band even if the
coefficients were the same for all 10 detectors.

A destriping algorithm for Band 26 devised by C. Moeller was
implemented. A new time-dependent LUT was added which gives
coefficients for a detector-specific cross-talk correction based on
the aggregated Band 5 radiances. The Band 26 scaled integers are
adjusted by the Band 5 correction term, which is the product of the
Band 5 radiance times the ratio of the Band 5 to Band 26 scaling
factors times the LUT correction value for that detector. In addition
a new LUT which allows for a frame offset with regard to the Band 5
radiance was added. A LUT which switches the correction off or on was
also added.

Data set information:

MODIS Homepage
http://modis.gsfc.nasa.gov/data/dataprod/

and

MODIS Characterization Support Team
http://mcst.gsfc.nasa.gov/

Related URL
Link: GET DATA > LAADS
Description: Access Collection 5 data set MOD021KM from the LAADS FTP site


Link: GET DATA > LAADS
Description: Access Collection 4 data set MOD021KM from the LAADS FTP site


Link: GET DATA > LAADS
Description: LAADS Web. Search for all data in the Level 1 and Atmosphere Archive and Distribution System.


Link: GET DATA > MODAPS
Description: Web site for MODIS Collection 4 L1B and Geo data ordering


Link: GET DATA > LANCE
Description: Near real-time (NRT) data are available from MODAPS for certain Aqua and Terra MODIS L0, L1, L2, L2G, and L3 products. Whereas the standard MODIS forward processing acquires 2-hour L0 files for Aqua and Terra from EDOS within 7-8 hours of real time, LANCE-MODIS acquires session-based L0 files from EDOS and the end of the session is available within 10-30 minutes after real time.


Link: GET DATA > ECHO
Description: Refine your granule search with ECHO's next generation Earth Science discovery tool (Reverb) using information from this record.


Link: VIEW PROJECT HOME PAGE
Description: MODIS Science Team


Link: VIEW PROJECT HOME PAGE
Description: MODIS Characterization Support Team (MCST).


Link: VIEW PROJECT HOME PAGE
Description: MODIS Atmosphere Team


Link: VIEW RELATED INFORMATION
Description: Readme regarding accessing MODIS data from the LAADS FTP server.


Link: VIEW RELATED INFORMATION
Description: MODIS Characterization Support Team (MCST), Level 1B Product Information
and Status Page


Geographic Coverage
 N: 90.0 S: -90.0  E: 180.0  W: -180.0

Data Set Citation
Dataset Originator/Creator: MCST Team
Dataset Title: MODIS/Terra Calibrated Radiances 5-Min L1B Swath 1km Collection 004 and 005
Version: Collection 005
Issue Identification: MOD021KM
Online Resource: http://modaps.nascom.nasa.gov/services/about/products/MOD021KM.html


Temporal Coverage
Start Date: 2000-03-01


Location Keywords
GEOGRAPHIC REGION > GLOBAL
GEOGRAPHIC REGION > GLOBAL LAND
GEOGRAPHIC REGION > GLOBAL OCEAN
OCEAN > ATLANTIC OCEAN
OCEAN > PACIFIC OCEAN
OCEAN > INDIAN OCEAN


Data Resolution
Latitude Resolution: 1 km at nadir
Longitude Resolution: 1 km at nadir
Temporal Resolution: Two day repeat observations with a repeat orbit pattern every 16 days.


Science Keywords
SPECTRAL/ENGINEERING >INFRARED WAVELENGTHS >INFRARED RADIANCE    [Definition]
SPECTRAL/ENGINEERING >INFRARED WAVELENGTHS >REFLECTED INFRARED    [Definition]
SPECTRAL/ENGINEERING >INFRARED WAVELENGTHS >THERMAL INFRARED    [Definition]
SPECTRAL/ENGINEERING >VISIBLE WAVELENGTHS >VISIBLE RADIANCE    [Definition]


ISO Topic Category
IMAGERY/BASE MAPS/EARTH COVER


Platform
TERRA >Earth Observing System, TERRA (AM-1)    [Information]


Instrument
MODIS >Moderate-Resolution Imaging Spectroradiometer    [Information]


Project
DODS >Distributed Oceanographic Data System    [Information]
EOSDIS >Earth Observing System Data Information System    [Information]
OPENDAP >Open-source Project for a Network Data Access Protocol    [Information]
ESIP >Earth Science Information Partners Program    [Information]
TERRA >Earth Observing System (EOS), TERRA    [Information]


Keywords
BRDF
CALIBRATED
GEOLOCATED
NIR
RADIANCE
SWIR
TIR
VISIBLE
OPeNDAP
EOSDIS
NRT
LANCE


Data Set Progress
IN WORK


Data Center
L1 and Atmosphere Archive and Distribution System,Biospheric Information Systems Branch, Hydrospheric and Biospheric Sciences Laboratory, Earth Sciences Division, Science and Exploration Directorate, Goddard Space Flight Center, NASA    [Information]
Data Center URL: http://ladsweb.nascom.nasa.gov/
Dataset ID: MOD021KM Collection 5

Data Center Personnel
Name: LAADS USER SUPPORT TEAM
Phone: 301-731-2917, 1-866-506-6347 (toll-free - US only)
Fax: 301-577-6622
Email: modapsuso at sigmaspace.com
Contact Address:
LAADS User Support Team
4801 Forbes Boulevard
City: Lanham
Province or State: MD
Postal Code: 20706
Country: USA


MODIS Adaptive Processing System, Biospheric Information Systems Branch, Hydrospheric and Biospheric Sciences Laboratory, Earth Sciences Division, Science and Exploration Directorate, Goddard Space Flight Center, NASA    [Information]
Data Center URL: http://modaps.nascom.nasa.gov
Dataset ID: MOD021KM Collection 4

Data Center Personnel
Name: MODAPS OPERATION TEAM
Phone: 301-731-2917, 1-866-506-6347 (toll-free - US only)
Email: opsdist at sigmaspace.com



Distribution
Distribution_Media: Online (FTP)
Distribution_Format: HDF
Fees: No Fee


Personnel
GANG YE, PH.D
Role: DIF AUTHOR
Phone: 301-352-2109
Email: gang.ye at sigmaspace.com


LAADS USER SUPPORT TEAM
Role: TECHNICAL CONTACT
Phone: 301-731-2917, 1-866-506-6347 (toll-free - US only)
Fax: 301-577-6622
Email: modapsuso at sigmaspace.com
Contact Address:
LAADS User Support Team
4801 Forbes Boulevard
City: Lanham
Province or State: MD
Postal Code: 20706
Country: USA


MODAPS OPERATION TEAM
Role: TECHNICAL CONTACT
Phone: 301-731-2917, 1-866-506-6347 (toll-free - US only)
Email: opsdist at sigmaspace.com



Creation and Review Dates
DIF Creation Date: 2006-06-05
Last DIF Revision Date: 2013-06-10

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