Temperature, water vapour and cloud liquid water measurements at Hornisgrinde using a microwave profiler F. Madonna, A. Giunta, A. Amodeo, G. D’Amico, and G. Pappalardo Consiglio Nazionale delle Ricerche Istituto di Metodologie per l’Analisi Ambientale CNR-IMAA

CNR-IMAA - MP3014 Microwave Profiler The microwave profiler measures the sky brightness temperature at 12 frequencies: 5 frequencies are in the K-band (22.235, , , , 30 GHz), around 22 GHz water vapour resonance band; 7 frequencies are in the V-band (51.250, , , , , , GHz), around 60 GHz oxygen spyn-rotation band. Rate: > 12 s Accuracy: 0.5 K Resolution: 0.25 K Range: K Operational range: -20° - 50° C Scanning capabilities: 3D sky Beam width: 6.3° at 22.2 GHz, 4.9° at 30 GHz, 2.5° at 51.3 GHz and 2.4° at 58.8 GHz (full width half power) Output products: Neural network (Solheim et al., 1998) Temperature, water vapour, relative humidity and cloud liquid water profiles up to 10 km above the ground IPWV, ILW accuracy: >0.09 kg/m2, >4 g/m2. Profiles are output in 100 m from 0 to 1 km, 250 m above up to 10 km Ancillary parameters. Cloud base temperature measured using an infrared radiometer. Surface meterological parameters (p, T, RH) The microwave profiler measures the sky brightness temperature at 12 frequencies: 5 frequencies are in the K-band (22.235, , , , 30 GHz), around 22 GHz water vapour resonance band; 7 frequencies are in the V-band (51.250, , , , , , GHz), around 60 GHz oxygen spyn-rotation band. Rate: > 12 s Accuracy: 0.5 K Resolution: 0.25 K Range: K Operational range: -20° - 50° C Scanning capabilities: 3D sky Beam width: 6.3° at 22.2 GHz, 4.9° at 30 GHz, 2.5° at 51.3 GHz and 2.4° at 58.8 GHz (full width half power) Output products: Neural network (Solheim et al., 1998) Temperature, water vapour, relative humidity and cloud liquid water profiles up to 10 km above the ground IPWV, ILW accuracy: >0.09 kg/m2, >4 g/m2. Profiles are output in 100 m from 0 to 1 km, 250 m above up to 10 km Ancillary parameters. Cloud base temperature measured using an infrared radiometer. Surface meterological parameters (p, T, RH)

CNR-IMAA MP3014 measurement report

Database A preliminary investigation of the collected database has allowed to identify some interesting case studies related to the different convective scenarios occurred during the campaign. The following IOPs have been selected as possible case studies: IOP-4 (ab)High-pressure/Forced convection IOP-8 (ab)High-pressure convection IOP-11 (ab)High-pressure convection IOP-12Formation of cumulus clouds IOP-13 (ab) High-pressure/Forced convection IOP-14 (a) Formation of cumulus clouds IOP-16 Forced convection IOP-17 (ab) Weakly forced convection IOP-18 (ab) High-pressure convection

Temperature – 20 June 2007

Temperature – 24 August 2007

Relative Humidity (15 July 2007) Met Office NAE (North Atlantic and European) model MP3014 CNR-IMAA microwave profiler

Relative Humidity (20 July 2007) MP3014 CNR-IMAA microwave profiler Met Office NAE (North Atlantic and European) model

Relative Humidity (01 August 2007) Met Office NAE (North Atlantic and European) model MP3014 CNR-IMAA microwave profiler

LWP – scanning measurements Measurement at Hornisgrinde: - Clear23% - Cloudy (Tir > 250 K)77% a. Low-Cloud ceiling (Tir > 280 K)80% b. Rain (rain sensor) 8%  Need for accurate estimation of the LWP  Use of intensive scanning data (low off-zenith) to improve the LWP retrieval  Investigation of Time Structure Functions

Outlook The cross-comparison with the other profilers operational at Hornisgrinde is planned and preliminary comparisons with the lidars are already ongoing. The contemporaneous presence of lidars for measurements of temperature and water vapour and of a microwave profiler provides the opportunity to evaluate the possible synergies between these profiling techniques and to elaborate new algorithms for the measurement integration. Preliminary comparisons between the UHOH DIAL and the microwave profiler are already ongoing (see posters). In this preliminary investigation, a neural network retrieval has been used for the retrieval of the profiles and integrated variables (Solheim et al., 1998). A processing of the data collected by all the microwave profiler involved in the campaign using a single retrieval algorithm (Löhnert and Crewell, 2003), coordinated by University of Cologne, is planned. This will give a strong contribution to the harmonization of the database and to the managing of the data by the modellers and other end-users.

Measurement strategy ScaS1 (all vertical) Zenith pointing onlyΔt = 13 s ScaS2 (supersite cross-section ) Zenith (30’) and elevation (30’) Δt = 14 s Elevation obs. Cycle 5 min (180° - 0° from R to M) Angle step = 9° ScaS3 (along-wind cross-section) Elevation scanning only Δt = 14 s Obs. Cycle 5 min (180° - 0° from R to M) Angle step = 9° ScaS4 (Aircraft scenario)