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Integrated Profiling at the AMF

Integrated Profiling at the AMF. Kerstin Ebell 1 , Ulrich Löhnert 1 , Susanne Crewell 1 , Dave Turner 2 1 Institute for Geophysics and Meteorology, University of Cologne 2 SSEC, University of Madison – Madison, WI. 6th COPS Workshop, University of Hohenheim 27 – 29 February 2008. Motivation.

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Integrated Profiling at the AMF

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  1. Integrated Profiling at the AMF Kerstin Ebell1, Ulrich Löhnert1, Susanne Crewell1, Dave Turner2 1Institute for Geophysics and Meteorology, University of Cologne 2SSEC, University of Madison – Madison, WI 6th COPS Workshop, University of Hohenheim 27 – 29 February 2008

  2. Motivation Accurate information on the atmospheric state desireable for numerous applications • evaluation of NWP models, i.e. assessment of radiation schemes • development of parametrization schemes • validation of satellite products • data assimilation • … temporally highly resolved continuously and automatically Only possible through integration of multiple measurement principles 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  3. www.arm.gov www.arm.gov DPR 90/150 Cloud radar HATPRO Radiosondes Radiometer Integrated Profiling Technique (IPT) – Overview 1 • Integration = physically consistent combination of all employed measurement information • Need knowledge on: • inversion methods • instrument characteristics (theory, error) • forward model, i.e. radiative transfer • Background information 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  4. Integrated Profiling Technique (IPT) – Overview 2 • provides continuous vertical profiles of temperature, humidity and liquid water content (LWC) • needs information of different active and passive remote sensing instruments Application to measurements of ARM Mobile Facility + measurements of multi-spectral radiometers in the Black Forest (Supersite M) from April 1 to December 31, 2007 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  5. Integration of measurements in the framework of optimal estimation x=(T,q,log10(LWC)) y=(TB,Z) xa: a priori profiles of T, q, log10(LWC) Sa: a priori covariance matrix Se: combined measurement and forward model error covariance matrix Integrated Profiling Technique (IPT) – Overview 3 • Microwave radiometers • Cloud radar • A priori information (here radiosondes) CloudNet Target Categorization: • Each pixel is categorized in terms of the presence of liquid droplets, ice, insects or aerosol. • Discrimination between precipitating and non-precipitating clouds. 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  6. Example: 7 July 2007 • CloudNet Target Classification 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  7. Example: 7 July 2007 • retrieved profiles:temperature andhumidity temperature (K) absolute humidity (g/m3) 0-6:50 UTC: dew on radome 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  8. Example: 7 July 2007 • retrieved profiles:liquid water content radar reflectivity (dBZ) liquid water content (g/m3) liquid water path (g/m2) 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  9. Height above surface (km) Height above surface (km) Height above surface (km) T error (K) q error (gm-3) LWC error (gm-3) Example: 7 July 2007 • estimate of mean error LWP (g/m2) stat. retrieval HATPRO IWV (kg/m2) GPS Time in decimal hours on 20070707 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  10. „New“: Inclusion of multispectral IR measurements Objectives: • Enhancement of accuracy & vertical resolution for temperature and humidity profile retrieval in clear-sky cases (and below cloud) • Future: develop a powerful, complementary retrieval tool (AERI+MW+cloud radar) more accurate retrieval of cloud properties over a wider range of LWP (from very low to precipitating), inclusion of ice microphysics Atmospheric Emitted Radiance Interferometer (AERI) 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  11. Application to COPS measurements (May 25, 2007 – AMF) • Humidity retrieval shows potential of combining MW and AERI measurements only MW MW+AERI 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  12. Application to COPS measurements (May 4, 2007 – AMF) • Retrieval of ice microphysics from AERI (and MW) 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

  13. Summary • Derivation of physically consistent profiles of temperature, humidity and cloud liquid water within an optimal estimation framework (Integrated Profiling Technique) • Inclusion of target information in the retrieval (CloudNet target categorization) • Combination of MW and AERI shows potential for high-quality humidity retrieval • Application of IPT to whole AMF dataset (April-Dec. 2007) Be careful: problems when clouds are not detected • Attempt to derive cloud droplet concentration • Use IPT output for SW/LW radiative transfer applications, cloud fraction contained in MW-volume scans ( see poster S. Kneifel) • Combine MW & AERI in cloudy cases (liquid, ice & mixed-phase) Outlook 6th COPS Workshop, University of Hohenheim, 27 – 29 February 2008

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