MODIS_ACNDC: adiabatic cloud droplet number concentration

doi:10.1594/WDCC/MODIS_ACNDC

Quaas, Johannes; Boucher, Olivier

DatasetDOI
Summary
Cloud droplet number concentration [m-3] derived from the MODIS Terra dataset assuming adiabatic clouds. CDNC is computed from the joint histogram of cloud optical thickness (COD) and cloud-top droplet effective radius (CDR) for liquid water clouds as CDNC = 1.37 e-5 * COD^0.5 * CDR^-2.5 (CDR in m and CDNC in m-3; Brenguier et al., J. Atmos. Sci., 2000; Quaas et al., Atmos. Chem. Phys. Discuss., 2005).
No vertical distribution, CDNC is considered vertically constant in each cloud.
Project
MODIS (MODIS data)
Location(s)
World
Spatial Coverage
Longitude -180 to 180 Latitude -90 to 90 Altitude: 0 m
Temporal Coverage
2000-03-01 to 2005-02-28 (calendrical)
Use constraints
unrestricted
Data Catalog
World Data Center for Climate
Access constraints
registered users
Size
452.88 MiB (474878840 Byte)
Format
NetCDF
Status
completely archived
Creation Date
Download Permission
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Cite as
Quaas, Johannes; Boucher, Olivier (2005). MODIS_ACNDC: adiabatic cloud droplet number concentration. World Data Center for Climate (WDCC) at DKRZ. https://doi.org/10.1594/WDCC/MODIS_ACNDC

BibTeX RIS
Description
CDNC data is derived from MODIS-retrieved cloud optical thickness and
cloud-top droplet effective radius. Liquid water clouds only are used,
and COD and CDR are restricted to their most reliable values (4um <= CDR
<= 30um and 4 <= COD <= 70; Nakajima and King, J. Atmos. Sci., 1990).
However, for MODIS-retrieved CDR, problems are known (Breon and
Doutriaux-Boucher, IEEE Trans. Geosci. Remote Sens., 2005). The
assumption of adiabacity may not necessarily be valid, even though large
regions are considered.
We recommend to use CDNC for statistical studies rather than to rely on
absolute accuracy in single regions or short time-periods
Description
Missing values occur due to entirely clear sky grid-boxes (where thus no cloud retrieval is possible) or due to other retrieval problems (e.g.,instrument failure or unsuitable viewing geometries).
VariableCodeAggregationUnit
cloud_droplet_number_concentration
ACDNC (ECHAM5: 136)
dailycm-3
Contact typePersonORCIDOrganization
Author
Prof. Dr. Johannes Quaas
0000-0001-7057-194X
Max-Planck-Institut fuer Meteorologie
Author
Olivier Boucher
0000-0003-2328-5769
CNRS/Universite des Sciences et Technologies de Lille
Investigator
Prof. Dr. Johannes Quaas
0000-0001-7057-194X
Max-Planck-Institut fuer Meteorologie
Metadata
Dr. Hans Luthardt
-
Max-Planck-Institut fuer Meteorologie (MD)

Is described by

[1] DOI Quaas, J.; Boucher, O.; Lohmann, U. (2005). Constraining the total aerosol indirect effect in the LMDZ and ECHAM4 GCMs using MODIS satellite data. doi:10.5194/acpd-5-9669-2005

Parent

MODIS_ACDNC Adiabatic Cloud Droplet Number Concentration daily value
Details

Parent project(s)

MODIS data

[Entry acronym: MODIS_ACNDC] [Entry id: 2066454]