Satellite remote sensing using AVHRR, ATSR, MODIS, METEOSAT, MSG Ralf Meerkötter, Luca Bugliaro, Knut Dammann, Gerhard Gesell, Christine König, Waldemar Krebs, Hermann Mannstein, Bernhard Mayer, presented by Ulrich Schumann, DLR, Germany
NOAA/AVHRR Longterm observations of lineshaped contrails and of water/ice cloud properties over Europe
A European Cloud Climatology from NOAA/AVHRR data Monthly means of total cloud cover averaged over 11 years January April 90 70 50 % July September 30 10 R. Meerkötter (IPA) C. König (IPA) H. Mannstein (IPA) G. Gesell (DFD)
Monthly means of total cloud cover from NOAA/AVHRR data in comparison to data of the global circulation model ECHAM4.L39/CHEM Averaging area Summer 2003 R. Meerkötter (IPA) C. König (IPA) V. Grewe (IPA)
Cloud masks of two methods detecting high and thin clouds 10.04.1993 11.04.1993 12.04.1993 other thin NOAA/AVHRR DLR high other Ci thin Ci NOAA/TOVS LMD Cb R. Meerkötter (IPA) C. Stubenrauch (LMD)
Comparison of different data sets containing cloud cover related to high clouds (Cb + thick cirrus) + thin cirrus Monthly means, spatially averaged over Europe R. Meerkötter (IPA) C. Stubenrauch (LMD)
Comparison of different times series of cloud cover related to thin clouds Monthly means, spatially averaged over Europe R. Meerkötter (IPA) C. Stubenrauch (LMD)
Which contrail properties are most important? Optical depth Contrail area Microphysics for visible optical depth of 0.5 Radiative forcing at top the of atmosphere for visible optical depth at 0.55 um derived from 1-D radiative transfer (Meerkötter et al. 1999) related to 100 % contrail coverage
Two years of contrails in AVHRR data over Europe Many over sea, less over land, poor detection over mountains H. Mannstein (IPA) R. Meyer (IPA)
Average of the coverage by line-shaped contrails (1995-2000) with an overlay of flight routes from EUROCONTROL data of May 5 1995 R. Meyer (IPA) H. Mannstein (IPA)
Time series of monthly mean contrail coverage for the full lifetime of NOAA-14 2 + Daytime Nightime Data refer to the region 6 W to26 E and 42 N to 54 N % 0 1995 1996 1997 1998 1999 2000 2001 R. Meyer (IPA)
Mean contrail forcing for Europe Averaging day and night Averaging summer and winter Resulting in an annual average of 0.03 W/m 2 R. Meyer (IPA)
Meteosat/MVIRI Additional cirrus due to air traffic?
Meteosat: Cirrus cover and air traffic Meteosat image Air traffic density Thin cirrus algorithm 1.0 Thin cirrus cover 0.2 + actual slot sum of slots 0.0 Air traffic density (km/km 2 /h) 1.0 H. Mannstein (IPA)
Coverage Coverage Cirrus Mean air traffic density (km/km 2 /h) Thin cirrus Meteosat: Cirrus coverage and air traffic Result: ~ 3% additional cirrus due to air traffic and ~0.3 % due to linear contrails Mean air traffic density (km/km 2 /h) H. Mannstein (IPA)
Temperature [K] Temperature [K] Thermal IR window channel Mean air traffic density (km/km 2 /h) Water vapour channel Meteosat: Blackbody temperatures and air traffic Result: Temperatures decrease in areas with heavy air traffic compared to areas without air traffic thermal IR: ~ 6.5K lower water vapour: ~ 2.5K lower Mean air traffic density (km/km 2 /h) H. Mannstein (IPA)
Meteosat Second Generation New horizons for cloud remote sensing Meteosat MSG NOAA/AVHRR 0.5 2.0 6.0 10.0 14.0 [micron]
MSG: Retrieval of optical depth and effective radius for water clouds MSG color composit Optical depth Effective radius 12.02.2003, 13:30 UTC New software package at DLR/IPA based on EUMETSAT scenes analysis L. Bugliaro (IPA) W. Krebs (IPA)
24.04.2003, 8:42 UTC MSG: Detection of cirrus clouds SEVIRI color composit Cirrus from A: brightness temperature difference TIR8 -TIR20 B: brightness temperature TIR08 A+B: both tests L. Bugliaro (IPA) W. Krebs (IPA)
Cirrus parameters from ERS-2/ATSR-2 ATSR-2 Image Effective Radius Cloud optical depth (0.55 µm) South of Shetland Island 15.8.00, 10:34 UTC 10 30 50 70 (µm) 1 3 5 K. Dammann (IPA)
Cirrus parameters from ERS-2/ATSR-2 ATSR-2 Image Effective Radius Cloud optical depth (0.55 µm) Channel area 31.8.00, 11:06 UTC 10 30 50 70 (µm) 1 3 5 K. Dammann (IPA)
MODIS: Cloud mask example for 30.10.2003 over Europe Color composit Land Cirrus Snow or Ci German Remote Sensing Data Center Wat. Cloud Snow G.Gesell (DFD)
Conclusions Done: Line-shaped contrail cover, optical thickness, radiative forcing, understood METEOSAT/air traffic correlation analysis indicates that additional cirrus cover induced by aircraft is far larger than the cover by line-shaped contrails Tools developed (but still to be refined) for cirrus analysis from AVHRR, METEOSAT, MSG, ATSR, MODIS Open: Complete and verify remote sensing estimates of cirrus properties Quantify cirrus changes and related RF from air traffic by long-term and largescale correlation between remote sensing data (MSG etc.) and air traffic data Identify the impact of aerosols on cloud and precipitation properties