RMS Physical Processes Specialist Group The current (January 29 1996) status is january meeting on Discretization cancelled due to lack of speakers April 10 1996 meeting on cloud phase at UMIST - see info attached October 23 1996 Meeting arranged by A Baran UKMO on ice crystals at Royal Society - List of speakers and other information attached. Meeting proposed by Keith Shine 'anomalouss absorption in clouds'. Possible for 1996/97 season other possible topics for 1996/97 onwards water vapour convection aerosols and radiation boundary layer/surface exchanges Please let me know if you would like to attend the meetings in April and October . Also if you would be interested in speaking at future meetings suggested above please let me know and indicate the likely subject matter. regards Sue Ballard spballard@meto.govt.uk UMIST MEETING ~~~~~~~~~~~~~ Royal Meteorological Society Physical Processes Specialist Group meeting on 'Observations and Modelling of Cloud Phase and its impact on Precipitation and Radiation' organiser Prof Tom Choularton to be held at UMIST, Manchester 10 April 1996 from 10.30 am 1. Cloud Glaciation via the Hallett - Mossop Process John Latham, UMIST 2. Nucleation of ice particles in orographic cirrus Amanda Spice,MRF 3. The Effect of layering on ice multiplication processes Doug Johnson,MRF 4. Observations of Mixed Phase Clouds using microwave radiometry Steve English, UKMO 5. Measurements of mixed Phase Clouds in Antartica Tom Lachlan-Cope, BAS 6. Parametrization of Cloud Phase in the Met Office Unified Model Sue Ballard, UKMO 7. Observations of the Ice Phase in Convective Clouds and Validation of Cloud Resolving Models Phil Brown, JCMM 8. Sensitivity of climate simulations to mixed phase cloud representation Dave Gregory, ECMWF 9. The parameterisation of secondary ice particle production in Global Climate Models Tom Choularton, UMIST for further information please contact Prof Tom Choularton, e-mail t.w.choularton@umist.ac.uk , tel 0161 2003950 or Sue Ballard , e-mail spballard@meto.govt.uk, tel 01344 856487 Please let Sue Ballard know if you are interested in attending to assist in planning arrangements. -------------------------------------------------------------------------- TITLE: Cirrus Crystal Properties: Observation and Modelling -------------------------------------------------------------- 23rd October 1996: at the Royal Society. Organisers A. J. Baran (email: ajbaran@meto.govt.uk; Tel: 01344 856409) J. S. Foot (email: jsfoot@meto.govt.uk; Tel: 01252 395401) Registration fee 13 pounds inclusive of buffet lunch, tea/coffee and biscuits. Structure ----------- Tea coffee available from 9:15 A.M: Part I 10:00 A.M Lunch 12:30 P.M Part II 1:35 P.M tea break 3:30 P.M Part III 4:00 P.M End 5:30 P.M Speakers: Confirmed ----------- 1. Peter Francis (Meteorological Research Flight) "Aircraft measurements of the radiative and microphysical properties of cirrus clouds" 2. Anthony Baran (Meteorological Office) and Simon Brown (Mullard Space Science Laboratory, UCL) "Ice water path, crystal size and habit retrievals using the dual view of ATSR-2: Results of validation exercises" 3. David Mitchell (Desert Research Institute, U.S.A) "A new cirrus radiation and satellite retrieval scheme for mean ice particle size, shape and ice water path" 4. Andreas Macke (NASA-GISS, New York, U.S.A) "Radiative transfer in cirrus clouds: What is the opposite of a sphere ?" 5. John Edwards (Hadley Centre) "Preliminary studies of parameterizations of Non-spherical ice crystals in the Unified Model" 6. C. P. Saunders (UMIST) "Laboratory measurements of ice crystal phase functions" 7. P.Jonas (UMIST) "Observations of the structure of cirrus clouds" 8. J. Russell (Imperial College) "The retrieval of temperature and Infrared optical depth of optically thin cirrus from ATSR data" POSSIBLE (Yet to be confirmed, i.e already invited): ----------------------------------------------------- J. S. Foot (Meteorological Research Flight) (Invited) J. Desclorites (University of Lille, France) (Polder) (Invited) P. Brown (JCMM) (Cirrus properties using Radar, depends on Chilboton Radar results) (Invited) Someone from aberystwyth possibly on Lidars ? Dr Foot to approach. RATIONALE ------------ As Arking (1991) says "Cloud parameterization is very critical to climate feedback. It is necessary to account for changes in cloud liquid water and cloud particle size and phase, in addition to cloud amount and height distribution, before one can assess the role of clouds in climate change." Cirrus clouds are the least understood of cloud types as far as their microphysics and life cycles are concerned with. As stated in Stephens et al (1990) "Characterization of the shape ans size of ice crystals in terms of their environmental parameters continues to be a subject of extensive research in cloud physics and is a topic that, through the dependence of both cloud albedo and emittance on microphysical parameters, is also crucial to the cloud-climate problem" This meeting will concentrate on some of these aspects especially the importance of crystal size and shape, including the radiative properties of cirrus. The point of this meeting is to draw U.K. researchers together, those included in field, laboratory,satellite and cloud modelling of cirrus in order to ascertain what the priorities are, and how we can help each other. For this will we also draw from the experience of our American colleagues, where most of this work is being done, who will also be able to inform us of the most recent work going on in the United States -- Susan P Ballard email: spballard@meto.govt.uk