APOLLO Cloud PropertiesChallenges and Requirements after 28 Years of Experience at DLR

Lars Klüser, Niels Killius and Gerhard Gesell

www.DLR.de • Chart 1 APOLLO Cloud Properties • Gesell et al • 2015-04-20

The history of APOLLOAVHRR Processing scheme Over cLouds Land and Ocean

- 1986 Development at Robert Hooke Institute by Roger Saunders and Theo Kriebel (uses 5 AVHRR channels and allows quantitative analysis)

- 1987 Implementation of a modular Version into ISM at DLR (ISM Interactive System Meteorology based on McIDAS of SSEC)

- 1987 Implementation of snow/ice/cloud separation

- 1991 Development of a standalone UNIX-Version

- 1995 Adaptation to ATSR data

- 1997 Start of the operative processing for a „European Cloud Climatology“

- 2003 Implementation into the operative processing chain of DFD

- 2003 Start of an NRT-service of APOLLO-based images on wdc.dlr.de for the support of synoptic weather view

- 2004 Adaptation to SEVIRI

- 2005 and later further adaptations and mostly minor improvements

www.DLR.de • Chart 2 APOLLO Cloud Properties • Gesell et al • 2015-04-20

Projects with contributions from APOLLO

- PAGODA (Project for ATSR and GOME data application – national project - ATSR)

- ECC („European Cloud Climatology“ – DLR collection of cloud parameters - AVHRR)

- CLOUDMAP2 (cloud parameters – AVHRR/MODIS)

- COBI (Cold Bias in Atmosphere General Circulation Models – national project - AVHRR)

- SYNAER (aerosol parameters – ATSR/AATSR)

- CONTRAILS (contrails „climatology“ - AVHRR)

- WISENT (Energy Meteorology (solar power) – national project - SEVIRI)

- HELIOSAT (solar energy - SEVIRI)

- HGF EOS (aerosol-cloud interactions, AATSR)

- ESA CCI Cloud (cloud parameters – AVHRR)

- ESA CCI Aerosol (aerosol parameters – AATSR)

- MACC-III (solar energy estimations – SEVIRI)

www.DLR.de • Chart 3 APOLLO Cloud Properties • Gesell et al • 2015-04-20

Calibration in APOLLO and generated datasets

- Up to N-14 calibration and its administration within APOLLO – from N-15 up to now L1b-input into APOLLO (reflectances and temperatures, radiances for CH3B)

- Within DFD utilization of calibration tools provided by Seaspace-TeraScan and archived NOAA-NESDIS calibration coefficients for AVHRR – up to N-14 also other ways gone

- For (A)ATSR and SEVIRI external sources of calibration (SCENES-SW for SEVIRI)

- ECC based on all archived AVHRR/HRPT data at DFD

- AVHRR processing chain cloud masks and products based only on the operational platforms

- Products generated for the NRT-service on wdc.dlr.de (AVHRR)

- Products based on SEVIRI for solar energy projects (daytime only from 2004 onwards)

www.DLR.de • Chart 4 APOLLO Cloud Properties • Gesell et al • 2015-04-20

Shortcomings and need for a major re-programming

www.DLR.de • Chart 5 APOLLO Cloud Properties • Gesell et al • 2015-04-20

- No consistent calibration convention over all platforms and sensors

- Old-fashioned coding and partly un-optimized run-time environment

- Different versions for different sensors of the AVHRR heritage

- Not including some of the latest retrieval methodologies for cloud parameters

- No complete datasets for all archived AVHRR/HRPT data at DFD available up to now

Needs a re-coding and re-implementation and to be updated with the latest methodologies

For TIMELINE this update is neccessary

TIMELINE is the suitable occasion and environment to do this providing e.g. consistent calibration etc

APOLLO APOLLO_NG

APOLLO APOLLO_NGimprovements and new features

www.DLR.de • Chart 6 APOLLO Cloud Properties • Gesell et al • 2015-04-20

- Probabilistic cloud detection

- Cloud probability is new diagnostic variable and allows for cloud mask adaptation based on required degree of confidence

- Probabilistic retrieval of cloud optical depth, effective radius and thermodynamic phase directly yields uncertainty for each variable

- CTT retrieval based on IR optical depth (with tir = tvis/2.13) and thus also for cirrus

yP

xPxyPyxP

||

APOLLO_NGexamples and outlook

www.DLR.de • Chart 7 APOLLO Cloud Properties • Gesell et al • 2015-04-20

cloud probability cloud OD

cloud top Reff cloud OD

uncertaintyJuly 15, 2008

AVHRR on NOAA-18

- APOLLO_NG already tested for: AVHRR, AATSR, SEVIRI, VIIRS

- Contributions to: TIMELINE, Aerosol_CCI, MACC-III, CSP-FoSYS, GlobTemp RR, …