This data set is only available for a restricted user group, please contact us if you want to access these data.
RESTRICTED only accessable in CEN/MPI net or via CliSAP login What does that mean?
MODIS stands for MODerate resolution Imaging Spectroradiometer. This sensor, equipped with 36 spectral channels from the visible into the infrared frequency range operates from aboard the EOS-TERRA and EOS-AQUA satellites since 2000 and 2002, respectively. Thanks to its high spectral resolution and the large number of different channels a large number of different atmospheric parameters can be retrieved. Here we refer to the cloud properties parameter data sets.
The MODIS cloud parameter products are based on calibrated, geo-located reflectances and radiances measured at a variety of the MODIS channels. Different approaches are used to derive the parameters. Cloud top parameters for mid- and high level clouds, e.g., are derived using a CO2 slicing technique combined with numerical and radiative transfer model input as described in Menzel et al. 2015. The variety of the approaches used is too large to allow a proper representation of these here within a few lines. Therefore we refer to the MODIS-Atmosphere Group webpage and to the references section - here in particular to the ATBD for MOD06/MYD06 level-2 products and to the User Guide.
We list the cloud parameters which we offer via ICDC in the following parameter lists for:
- Cloud Fraction
- Cloud Water Path
- Cloud Top Parameters
- Cloud Radiative Properties
- Cloud Parameter Joint Histograms
This is part of the level-3 MOD08/MYD08 data set derived from MOD06/MYD06 level-2 products of the MODIS Collection 6.1.
Additionally, we offer monthly mean cloud droplet number concentrations (CDNC) for years 2003 through 2015 computed from MODIS AQUA (see Bennartz and Rausch in References)
Last update of data set at ICDC: May 8, 2020.
|Type of data||Comment||Specific Wavelengths||Histograms|
|Solar angles||Azimuth & zenith|
|Sensor angles||Azimuth & zenith|
|Surface Property Fractions||Ocean, Coast, Desert, Land|
|Total Cloud Fraction||All, Day & Night||X|
|Cirrus Cloud Fraction||IR & SWIR|
|Cloud Fraction, cloudy & partly cloudy pixels||different phases|
|Cloud Fraction, single layer clouds||liquid & ice|
|Cloud Fraction, multilayer clouds||different phases|
|Cloud Fraction, cloudy & partly cloudy pixels||liquid & ice||1.6 µm, 3.7 µm, 1.6 & 2.1 µm|
|Cloud Top Temperature||All, Day & Night||X|
|Cloud Top Pressure||All, Day & Night||X|
|Cloud Top Geopotential Height||All, Day & Night||X|
|Cloud Water Path, cloudy & partly cloudy pixels||different phases|
|Cloud Water Path, single layer clouds||liquid & ice|
|Cloud Water Path, cloudy & partly cloudy pixels||liquid & ice||1.6 µm, 3.7 µm, 1.6 & 2.1 µm|
|Cirrus Cloud Reflectance|
|Cloud Effective Emissivity||All, Day & Night||X|
|Cloud Optical Thickness, cloudy & partly cloudy pixels||different phases||X|
|Cloud Optical Thickness, single layer clouds||liquid & ice|
|Cloud Optical Thickness, cloudy & partly cloudy pixels||liquid & ice||1.6 µm, 3.7 µm, 1.6 & 2.1 µm||X|
|Cloud Particle Effective Radius, cloudy & partly cloudy pixels||different phases||X|
|Cloud Particle Effective Radius, single layer clouds||liquid & ice|
|Cloud Particle Effective Radius, cloudy & partly cloudy pixels||liquid & ice||1.6 µm, 3.7 µm, 1.6 & 2.1 µm||X|
|The full description of the file content is given in the parameter lists under Description|
|Cloud Droplet Number Concentration||monthly|
Period and temporal resolution:
- 2000-02-24 to 2020-03-31 (MODIS EOS-TERRA)
- 2002-07-04 to 2020-03-31 (MODIS EOS-AQUA)
- 2003-01 to 2015-12 (MODIS EOS-AQUA CDNC)
Coverage and spatial resolution:
- Spatial resolution: 1° x 1°, cartesian grid
- Geographic longitude: 180°W to 180°E
- Geographic latitude: 90°S to 90°N
- Dimension: 360 columns x 180 rows
- Altitude: following terrain
- TERRA: August 7-18 2000; June 16 - July 2 2001; March 20-27 & April 15 2002; December 21-22 2008
- AQUA: July 30 - August 6 2002
The offered gridded Level-3 cloud property data contain as a measure of uncertainty the standard deviation of all level-2 grid cells used for the computation of the level-3 product.
For some of the products the confidence flags of the level-2 products are used to come with with uncertainty estimates (as described in the level-3 data ATBD). In contrast to the MODIS Aerosol Properties product, no histograms about data quality are provided.
This data set is from Collection 6.1 of the MODIS collection 6 product family. Hence a substantial number of inconsistencies and potential retrieval problems, which have been identified in the past product versions (4, 5), has been taken care of in this newest MODIS product release. In addition several new variables are included, e.g. 1) cloud top height, 2) cirrus / high cloud fraction, 3) joint histograms of all cloud top parameters with the cloud top pressure, 4) retrievals of cloud water path, particle effective radius, optical thickness, and fractions also for partly cloudy pixels, and finally, 5) separate retrievals of these parameters for MODIS bands at 1.6 µm, at 3.7 µm, and 1.6 and 2.1 µm combined.
The effect of radiometric calibration drift of MODIS EOS-TERRA band 29 (8.6 µm) as well as other effects of the sensor, such as cross-talk between adjacent frequency bands, on the data products have been mitigated in this newest collection 6.1 product.
We refer to the documents listed in the References.
MODIS - Atmosphere Level-3 Product Group
NASA / GSFC
email: steve.platnick (at) nasa.gov
MODIS - Cloud Optical Properties
NASA / GSFC
email: gala.wind (at) nasa.gov
MODIS - Cloud Top Properties
Space Science Engineering Center (SSEC) / WISC
email: richard.frey (at) ssec.wisc.edu
ICDC / CEN / University of Hamburg
email: stefan.kern (at) uni-hamburg.de
- MODIS - Atmosphere Group Webpage
- Platnick, S., et al., MODIS Cloud optical properties: User guide for the Collection 6/6.1 level-2 MOD06/MYD06 product and associated level-3 data sets. v1.1, July 2018 (pdf, not barrier-free)
- MODIS ATBD for Level-3 Global Gridded Atmosphere Products (Collection 006, v4.3) (pdf, not barrier-free)
- Hubanks, P, (2017): Collection 6.1 Change Document MODIS Atmosphere Level-3 Global Products, Adnet Systems, Lanham, MD, Version 1.0, August 23 2017, 20 pp, see also modis-atmos.gsfc.nasa.gov/documentation/collection-61 (pdf, not barrier-free)
- Moeller, C., and R. Frey, Terra MODIS Collection 6.1 calibration and cloud product changes, v1.0, June 27, 2017. (pdf, not barrier-free)
- Moeller, C., and R. Frey, Collection 6.1 Terra MODIS IR Bands (MOD021KM) calibration change supplement. v1.0, June 27 2017. (pdf, not barrier-free)
- Platnick, S., et al., Collection 6.1 change summary for the MODIS cloud optical property (06_OD) algorithm, July 17 2017. (pdf, not barrier-free)
- King, M. D., et al., (2003), Cloud and aerosol properties, precipitable, water, and profiles of temperature and water vapor, Trans. Geosci. Rem. Sens., 41(2), 442-458. (pdf, not barrier-free)
- Baum, B. A., et al. (2012), MODIS cloud-top property refinement for Collection 6, J. Appl. Meteorol. Climatol., 51(6), 1145-1163. (pdf, not barrier-free)
- King, M. D., et al. (2013), Spatial and temporal distribution of clouds observed by MODIS onboard the Terra and Aqua Satellites, IEEE Trans. Geosci. Rem. Sens., 51(7), 3826-3852. (pdf, not barrier-free)
- Lyapustin, A., et al., (2014), Scientific impact of MODIS C5 calibration degradation and C6+ improvements, Atmos. Meas. Tech., 7, 4353-4365. (pdf, not barrier-free)
- Cho, H.-M., et al. (2015), Frequency and causes of failed MODIS cloud property retrievals for liquid phase clouds over global oceans, J. Geophys. Res. - Atmos., 120, 4132-4154. (pdf, not barrier-free)
- Wang, T., et al., (2016), Validation of MODIS cloud mask and multilayer flag using CloudSat-CALIPSO caloud profiles and a cross-reference of their cloud classifications, J. Geophys. Res. - Atmos., 121, 11620-11635. (pdf, not barrier-free)
- Yi, B., et al. (2017), A comparison of Aqua MODIS ice and liquid water cloud physical and optical properties between collection 6 and collection 5.1: Pixel-to-pixel comparisons, J. Geophys. Res. - Atmos., 122, 4528-4549. (pdf, not barrier-free)
- Bennartz, R., and J. Rausch (2017), Global and regional estimates of warm cloud droplet number concentration based on 13 years of AQUA-MODIS observations, Atmos. Chem. Phys., 17, 9815-9836. (pdf, not barrier-free)
Please cite the data as follows:
Platnick, S., et al., 2017. MODIS Atmosphere L3 Daily Product. NASA MODIS Adaptive Processing System, Goddard Space Flight Center, USA: http://dx.doi.org/10.5067/MODIS/MOD08_D3.061 [last accessed: April 27, 2020]
(if MODIS EOS-AQUA data are used accordingly: dx.doi.org/10.5067/MODIS/MYD08_D3.061)
and acknowledge the source of your data download as:
Original MODIS collection 6.1 cloud parameter data provided in hdf format by https://ladsweb.modaps.eosdis.nasa.gov/ were downloaded in netCDF file format from the Integrated Climate Data Centre (ICDC), CliSAP/KlimaCampus, University of Hamburg, Hamburg, Germany, http://icdc.cen.uni-hamburg.de
For the CDNC data set please refer the the paper by Bennartz and Rausch (see above).