|
MERIS black-sky albedo database |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Tropospheric
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
|
NO2
- global CH2O - global CO - global |
|
|
|
UV
- UV index - UV dose |
|
|
|
Ozone
- total column - global field - ozone bulletin - ozone profiles - tropospheric |
|
|
|
Aerosol
- ADRE - aerosol index Methane - global CO2 - global Clouds - cloud info Surface - solar irradiance |
|
|
|
Volcanic plume
- SO2 & AAI |
|
|
|
Albedo
- climatologies Fluorescence - sun-induced |
17 April 2024
Christoph Popp has created a surface albedo climatology based on MERIS Albedomap data. For
each MERIS channel the black-sky albedo (BSA) for all months is stored in
a zip file. There are also files with quality flags (one for each month).
The meaning of the values of the flags are:
0: snow- and ice-free land pixels
1-100: snow fraction (compiled from the MODIS MOD10 - Snow cover
product)
240: water pixels filled with GOME-1 surface LER values
250: filled with value from closest month
Note that water pixels at 865 and 885 nm are not filled with GOME-1
surface LER values since the closest wavelength band available from
GOME-1 is the one at 772 nm. An alternative for this would be the SCIAMACHY surface LER database, which does provide wavelength
bands near these wavelengths. Additionally, this database offers a
higher quality and additional wavelength bands that are closer to the
MERIS bands. If wavelengths above 772 nm are not required, a better
alternative for water pixel replacement would be the GOME-2
surface LER database.
An IDL routine is
available which can read the files (returns albedo*1000 or the quality
flag). A description for reading the data with Fortran can be found here.
Validation of the MERIS BSA climatology based on direct intercomparison
with the SCIAMACHY surface LER climatology is described here.
If you're planning to use this database, please refer to the scientific
paper describing the database, which is available here.
Some examples of
the database:
|
|
|
| MERIS albedo over land, GOME albedo over sea. Month: August |
MERIS albedo over land, no values over sea. Month: August |
MERIS quality flags. Month: August |
Archive:
The MERIS BSA database is available in the form of separate zip files for
each of the thirteen wavelength bands:
merisTOTL[mm]_[wvl].dat
== monthly black-sky albedo (land) or minimum LER (sea) values for month[mm]and wavelength[wvl]nm
Additionally, there are also FLAG files
quality_flags_[mm].dat
for the TOTL files, one for each month and valid for all wavelength bands.
These are zipped together in a 14-th file. The reason for splitting up the
database is to minimise the download effort in case you do not need the
data of all wavelength bands.
| MERIS wavelength | GOME-1 wavelength | Monthly data files (zipped) | Monthly GIF images (zipped) |
| 412 nm | 416 nm | meris_bsa_412.zip | zip file of images |
| 442 nm | 440 nm | meris_bsa_442.zip | zip file of images |
| 490 nm | 494 nm | meris_bsa_490.zip | zip file of images |
| 510 nm | 494 nm | meris_bsa_510.zip | zip file of images |
| 560 nm | 555 nm | meris_bsa_560.zip | zip file of images |
| 620 nm | 610 nm | meris_bsa_620.zip | zip file of images |
| 665 nm | 670 nm | meris_bsa_665.zip | zip file of images |
| 681 nm | 670 nm | meris_bsa_681.zip | zip file of images |
| 707 nm | 670 nm | meris_bsa_707.zip | zip file of images |
| 754 nm | 758 nm | meris_bsa_754.zip | zip file of images |
| 775 nm | 772 nm | meris_bsa_775.zip | zip file of images |
| 865 nm | -- | meris_bsa_865.zip | zip file of images |
| 885 nm | -- | meris_bsa_885.zip | zip file of images |
| Quality flags | quality_flags.zip | ||
|
|||
Documentation:
- C. Popp, P. Wang, D. Brunner, P. Stammes, Y. Zhou, and M. Grzegorski, MERIS albedo climatology for FRESCO+ O2 A-band cloud retrieval, Atmos. Meas. Tech., 4, 463-483, doi:10.5194/amt-4-463-2011, 2011 (PDF)
- L.G. Tilstra, O.N.E. Tuinder, P. Wang, and P. Stammes, Surface reflectivity climatologies from UV to NIR determined from Earth observations by GOME-2 and SCIAMACHY, J. Geophys. Res. Atmos. 122, 4084-4111, doi:10.1002/2016JD025940, 2017 (PDF)