Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Expand
titleClick here to expand the related documents (D1-D3))


Reference ID

Document

D1

Algorithm Theoretical Basis Document, v.6.2. ESA Cloud_cci.
https://climate.esa.int/media/documents/Cloud_Algorithm-Theoretical-Baseline-Document-ATBD_v6.2.pdf
Last accessed on 27/01/2021

D2

Product User Guide, v5.1. ESA Cloud_cci,
https://climate.esa.int/media/documents/Cloud_Product-User-Guide-PUG_v5.1.pdf
Last accessed on 27/01/2021

D3

Comprehensive Error Characterisation Report, v4.1. ESA Cloud_cci. https://climate.esa.int/media/documents/Cloud_Comprehensive-Error-Characterisation-Report-CECR_v4.1.pdf
Last accessed on 27/01/2021


...

  • ATSR-2, which flew on the second European Research Satellite (ERS-2) from June 1995 until January 2008. ERS-2 lost global coverage in June 2003, due to failure of the onboard data storage; Cloud_cci data do not extent beyond this date (thus providing approximately one-year of overlap with the succeeding AATSR product). Due to an instrument failure there is no data for 01/1996-06/1996.
  • Advanced-ATSR (AATSR), which flew on ENVISAT from May 2002 until the satellite's failure in April 2012.

...

Anchor
table1_1
table1_1
Table 1-1: GCOS targets for cloud properties ECVs. Note that the Cloud_cci doesn't meet the temporal requirements due to the nature of the satellite observations, but exceeds the spatial resolution and aims to achieve the uncertainty and stability requirements.

Quantity

Cloud_cci variable

Targets

Cloud amount

CFC

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 0.01-0.05
  • Stability: 0.01/decade

Cloud top pressure

CTP

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 15-50 hPa
  • Stability: 3-15 hPa/decade

Cloud top temperature

CTT

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 1-5 K
  • Stability: 0.25 K/decade

Cloud Optical Depth

COT

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 10%
  • Stability: 5% /decade

Cloud Water Path

LWP, IWP

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 25%
  • Stability: 5% /decade

Effective particle radius

CER

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 1μm
  • Stability: 1μm/decade

1.3 Data usage information

...

C3S-312bL1-L3C-MONTHLY-CLOUD-INSTORACPLATFORM{}YYYYMM{_}_fvVVV.nc,

where INST and PLATFORM refer to the instrument and platform from which data originates (either ATSR2 and ERS2, or AATSR and ENVISAT for the CDR, or SLSTR and Sentinel-3a or -3b for the ICDR), YYYYMM provides the year and month covered by the monthly mean product, and VVV denotes the product version (3.0 for the TCDR, 3.1 for the ICDR).

...

Anchor
table1_2
table1_2
Table 1-2: Cloud properties included in Cloud_cci TCDR and SLSTR ICDR monthly products.

Property

Unit

Variable name

Comment

Cloud fractional cover

-

cfc


Cloud-top pressure

hPa

ctp


Cloud-top height

km

cth


Cloud-top temperature

K

ctt


Cloud optical thickness

-

cot

Only retrieved on day-light side of orbit

Cloud effective radius

µm

cer

Only retrieved on day-light side of orbit

Cloud liquid water path

gm-2

lwp

Only retrieved on day-light side of orbit

Cloud ice water path

gm-2

iwp

Only retrieved on day-light side of orbit

For lists and details of known issues and limitations of the data, the user is referred to the referenced ATBDs and papers in Section 1.1. In particular, it should be noted that the monthly mean is computed using data from sun-synchronous polar-orbiting satellites, with a relatively narrow swath. Thus, it cannot be considered a representation of the mean properties of clouds across the whole month for two reasons:

...

  • ATSR-2, which flew on the second European Research Satellite (ERS-2) from June 1995 until January 2008. ERS-2 lost global coverage in June 2003, due to failure of the onboard data storage; Cloud_cci data do not extent beyond this date (thus providing approximately one-year of overlap with the succeeding AATSR product). Due to an instrument failure there is no data for 01/1996-06/1996. Gaps in the daily means can occur and are also due to instruments that are not working normally. 
  • Advanced-ATSR (AATSR), which flew on ENVISAT from May 2002 until the satellite's failure in April 2012. Gaps in the daily means can occur and are also due to instruments that are not working normally. 

When referred to in terms of a continuous data record, these two instruments are commonly described as (A)ATSR. The preceding ATSR-1 instrument lacked the visible-NIR channels provided by (A)ATSR and thus isn’t included in the Cloud_cci product.

...

Anchor
table2_1
table2_1
Table 2-1: GCOS targets for cloud ECVs. Note that the Cloud_cci doesn't meet the temporal requirements due to the nature of the satellite observations, but exceeds the spatial resolution and aims to achieve the uncertainty and stability requirements.

Quantity

Cloud_cci variable

Targets

Cloud amount

CFC

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 0.01-0.05
  • Stability: 0.01/decade

Cloud top pressure

CTP

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 15-50 hPa
  • Stability: 3-15 hPa/decade

Cloud top temperature

CTT

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 1-5 K
  • Stability: 0.25 K/decade

Cloud Optical Depth

COT

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 10%
  • Stability: 5% /decade

Cloud Water Path

LWP, IWP

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 25%
  • Stability: 5% /decade

Effective particle radius

CER

  • Frequency: 3hr
  • Resolution: 50 km
  • Measurement uncertainty: 1µm
  • Stability: 1µm/decade


2.3 Data usage information

Cloud_cci products are provided in NetCDF (version 4), which are compliant with the conventions CF 1.8 and the NASA Global Change Master Directory (GCMD) Science Keywords vocabulary. Filenames follow the structure:

C3S-312bL1-L3C-DAILY-CLOUD-INSTORACPLATFORM{}YYYYMMDD{_}fvVVV{_}.nc,

...

Anchor
table2_2
table2_2
Table 2-2: Cloud properties included in Cloud_cci TCDR and SLSTR ICDR daily products.

Property

Unit

Variable name

Comment

Cloud fractional cover-day

-

cfc_day


Cloud fractional cover-night

-

cfc_night


Cloud-top pressure-day

hPa

ctp_day


Cloud-top pressure-night

hPa

ctp_night


Cloud-top height-day

km

cth_day


Cloud-top height-night

km

cth_night


Cloud-top temperature-day

K

ctt_day


Cloud-top temperature-night

K

ctt_night


Cloud optical thickness-day

-

cot_day


Cloud effective radius-day

µm

cer_day


Cloud liquid water path-day

gm-2

lwp_day


Cloud liquid water path-night

gm-2

lwp_night


Cloud ice water path-day

gm-2

iwp_day


Cloud ice water path-night

gm-2

iwp_night


For lists and details of known issues and limitations of the data, the user is referred to the referenced ATBDs and papers in Section 1.1.

...

Sus, O., M. Stengel, S. Stapelberg, G. McGarragh, C.A. Poulsen, A.C. Povey, C. Schlundt, G.E. Thomas, M. Christensen, S. Proud, M. Jerg, R.G. Grainger, R. Hollmann, 2018: The Community Cloud retrieval for Climate (CC4Cl) – Part 1: A framework applied to multiple satellite imaging sensors. Atmos. Meas. Tech., 11, 3373-3396, DOI: 10.5194/amt-11-3373-2018.


Info
iconfalse

This document has been produced in the context of the Copernicus Climate Change Service (C3S).

The activities leading to these results have been contracted by the European Centre for Medium-Range Weather Forecasts, operator of C3S on behalf of the European Union (Delegation agreement signed on 11/11/2014). All information in this document is provided "as is" and no guarantee or warranty is given that the information is fit for any particular purpose.

The users thereof use the information at their sole risk and liability. For the avoidance of all doubt , the European Commission and the European Centre for Medium - Range Weather Forecasts have no liability in respect of this document, which is merely representing the author's view.

...