Cel To develop and test radar based-algorithms to infer thevertical profiles of cloud properties such as ice and liquidwater content. To study the properties of natural clouds, theirevolution and their characteristics.An existing 94GHz radar will be upgraded to increase itssensitivity to clouds and will then be deployed alongside twoexisting 35 and 3 GHz radars at Chilbolton in the UK so that thethree radars, together with a 95GHz radiometer, can scan a commonvolume of cloud.The radar upgrade should take 10 months and will be followed by atwelve month period of observations with the three radars and theradiometer. Measurements will be made on both a statistical andan event basis, and will encompass low level water clouds such asstratocumulus, higher level cirrus clouds which are composed ofice particles only, together with clouds of mixed phase.Algorithms will be developed to infer cloud properties from theradar measurements at the three wavelengths. The 3GHzreflectivity is unaffected by attenuation or Mie scattering. Theincreased attenuation at the higher frequencies will be used toderive cloud liquid water content. For ice clouds theattenuation at all three radar frequencies is negligible, but thepresence of larger ice particles results in Mie scattering and areduced radar reflectivity at the higher frequency, and thisreduction can be used to derive a mean size for the iceparticles.In parallel with the establishment of algorithms to infer liquidand ice water content, particle size, and the efficiency of clouddetection by radar, studies will be carried out of cloudevolution. Climate models are very sensitive to the assumedterminal velocity of cirrus particles which affect thepersistence of ice clouds; direct radar measurements of thesevelocities will aid parameterisation schemes.Clouds represent one of the chief sources of uncertainty inclimate studies; small alterations to cloud parameterisationschemes in general circulation models leading to very differentglobal distributions of clouds. The ultimate aim is for aspaceborne cloud radar to provide vertically resolved globalcloud data, this first step is to provide ground based radar datato improve and validate parameterisation schemes. Dziedzina nauki engineering and technologyelectrical engineering, electronic engineering, information engineeringinformation engineeringtelecommunicationsradio technologyradarnatural sciencesearth and related environmental sciencesatmospheric sciencesclimatology Program(-y) FP3-ENV 1C - Specific research and technological development programme (EEC) in the field of the environment, 1990-1994 Temat(-y) 0102 - Anthropogenic climate change Zaproszenie do składania wniosków Data not available System finansowania CSC - Cost-sharing contracts Koordynator UNIVERSITY OF READING Wkład UE Brak danych Adres Earley Gate 2, Whiteknights, Palmer Building RG6 2AU READING / SILCHESTER Zjednoczone Królestwo Zobacz na mapie Koszt całkowity Brak danych Uczestnicy (3) Sortuj alfabetycznie Sortuj według wkładu UE Rozwiń wszystko Zwiń wszystko COUNCIL FOR THE CENTRAL LABORATORY OF THE RESEARCH COUNCILS Zjednoczone Królestwo Wkład UE Brak danych Adres Chilton OX11 0QX DIDCOT,HARWELL,CHILTON Zobacz na mapie Koszt całkowity Brak danych Società GF Galileo SMA Srl Włochy Wkład UE Brak danych Adres Via Albert Einstein 35 50013 Firenze Campi Bisenzio Zobacz na mapie Koszt całkowity Brak danych UNIVERSITE PAUL SABATIER DE TOULOUSE III Francja Wkład UE Brak danych Adres Avenue Edouard Belin 14 31400 TOULOUSE Zobacz na mapie Koszt całkowity Brak danych