Report from DAOS-WG Presented by Richard Swinbank Prepared by Roger Saunders with input from WG members

Current membership Ron Gelaro(D), Co-chair NASA, USA Roger Saunders(O), Co-chair Met Office, UK Stefan Klink(O) DWD, Germany Carla Cardinali(D) ECMWF Chris Velden(O) Univ Wisconsin-CIMSS, USA Tom Hamill(D) NOAA, USA Tom Keenan(O) CAWCR, Australia Rolf Langland(D) NRL, USA Bertrand Calpini (O) MeteoSwiss, Switzerland Andrew Lorenc(D) MetOffice, UK Florence Rabier(D/O) Météo-France Prof. Bin Wang(D), Chinese Academy of Sciences, China Michael Tsyroulnikov(D) HydroMet Centre, Russia Mark Buehner (D) Environment Canada Sharan Majumdar (D) RSMAS, Univ Miami, USA O=Observations D=Data Assimilation

DAOS-4 WG meeting Exeter June 2011 Review targetting paper Updates on THORPEX campaigns Review observing systems Review developments in data assimilation WG matters

METOP : MetOp ATOVS,MetOp IASI, MetOp ASCAT NOAA : NOAA15 ATOVS AMSUA, NOAA17 ATOVS HIRS, NOAA18 ATOVS, NOAA19 ATOVS OTHER LEO: EOS AIRS, F16 SSMIS, ERS, WINDSAT GEO : GOES, MTSAT, MSG Aircraft : AMDAR, AIREP SONDE : PILOT, TEMP SFC Land : SYNOP, BOGUS SFC Sea : BUOY,SHIP Total Impact = Number of soundings/profiles * mean observation Impact of each sounding/profile Impact of different observation platforms from forecast sensitivity diagnostic

5 The Concordiasi Project Additional observations over Antarctica for NWP F. Rabier, V. Guidard, S. Noton-Haurot, A. Doerenbecher, D. Puech, P. Brunel, A. Vincensini, H. Bénichou, Météo-France Ph Cocquerez, CNES A.Hertzog, F. Danis, IPSL/LMD T. Hock, S. Cohn, J. WangNCAR C. Sahin, A. Garcia-Mendez, J-N Thépaut ECMWF A. Cress, U. Pfluger, DWD R. Langland, NRL G. Verner, P. Koclas, CMC R. Gelaro, NASA/GMAO C. Parrett, R. SaundersMet Office Y. Sato JMA

6 CONCORDIASI Flights overview Sept 2010-January , a stable Austral Winter Polar Vortex

7 Sea-Ice limit 640 Dropsondes ( )

Participants CMC DWD ECMWF GMAO Météo-France Met Office JMA Data Assimilation Monitoring Statistics over the Antarctic RMS(O-F) Raob T Obs Count Raob T Radiosonde Background Temperature Departures (O-F) Courtesy F. Rabier, Météo-France All models have difficulty predicting lowest-level temperatures

9 Concluding remarks on ConcordIASI Concordiasi provided an unprecedented data coverage of meteorological observations over Antarctica Both dropsonde and gondola information seem to have a positive impact on forecast performance (preliminary results from NRL, DWD and MF) Gondola temperature data at 60hPa shows the largest model errors in areas of strong gravity-wave activity Dropsonde information confirms statistics obtained with radiosondes and provide a more global view Most models have problems predicting the lowest level temperatures

In –situ Measurements Issues for THORPEX Transition to BUFR for radiosondes provide new opportunities GPS total zenith delay gobal coverage In-situ soil moisture and temp Common format for precip radar data To improve estimates of solid precipitation and develop guidance on the accuracy and temporal resolution of solid precipitation parameters New observations needed for mesoscale

Ground-based GPS Observations available from E-GVAP

Global Extent ASSESS THE CURRENT AND POTENTIAL CAPABILITIES OF WEATHER RADARS FOR THE USE IN WMO INTEGRATED GLOBAL OBSERVERING SYSTEM (WIGOS ) by Ercan Büyükbaş, Turkish State Meteorological Service (TSMS) Radars now used to Verify NWP model Precipitation forecasts Need to advocate a common format worldwide to enable wider verification of precipitation

NCEP Stage IV obs (mm/day) CTRL – NCEP Stage IV NEW – NCEP Stage IV Impact of NCEP Stage IV assimilation on 12h forecasts of precipitation. Sept-Oct 2009 average (CY35R2; T511 L91)  ECMWF 2011  Mean bias and RMS error are reduced

Impact on forecast scores for other parameters (Z, T, wind, RH): - neutral or slightly positive impact on the global scale. - some hint of positive impact over Europe (days 4-5) and Asia (days 8-10). Direct 4D-Var assimilation of NCEP Stage IV rain data  ECMWF 2011  RMSE South. Hemis. 500hPa wind  RMSE North. Hemis. 500hPa wind  RMSE Europe 500hPa temperature  RMSE Asia 850hPa Temperature good Forecast Root Mean Square Error changes due to direct 4D-Var assimilation of NCEP Stage IV rain data 1 April – 6 June 2010, T1279 (~15 km global) L91

Satellite Measurements Issues for THORPEX Extended life of some research satellites helps to mitigate losses elsewhere Reduced thinning of AMSU-A shown to beneficial Hyperspectral sounder in GEO orbit now approved by Europe on MTG Contribution to GOS by nations increasing (e.g. FY- 3, Oceansat-2) to fill future gaps in GOS Challenge of assimilation of satellite data in high resolution local area models and extend use of advanced IR sounders (cloudy rads, use PCs,..)

ASCAT winds for Irene and model background Only one scat now used for NWP Trials using scatterometer on Oceansat-2 Importance of Scatterometer winds

A. Doerenbecher, Météo France The targeting procedure

Impact of dropsonde data for Irene

Comparison of different models Tropical cyclone track forecast errors during the Summer T-PARC period for four assimilation-forecast systems. The solid (dashed) lines represent parallel analysis-forecast cycles excluding (including) T-PARC dropwindsonde data.

DAOS-WG Statement on impact of targeted data For mid-latitude systems, the value of targeted data is found to be positive but small on average. The WSR programme has found that targeting results in some improvement in 2-3 day forecasts over N. America. Observations in dynamically sensitive areas have a bigger average impact per observation than those deployed randomly. The cumulative benefit of a small number of targeted aircraft observations to forecast accuracy over broad verification regions is smaller than that of other observing systems that provide observations with a more complete coverage. For forecasts of the track of TCs targeted observations have proven to be beneficial statistically. A simple sampling strategy of observing uniformly around the TC has been shown to be effective, with most models exhibiting an improvement. There is a need to assess the impact of targeted observations with more user-focused measures of the value of forecast improvements to society, while retaining the ability to get significant results from relatively short experiments.

DAOS-WG Future Directions Maintain links with ET-EGOS, WGNE, etc Next meeting in Madison Sep 2012 Joint meeting with MFWR under discussion DAOS remains a global focus not mesoscale Continue mix of Observations and DA Leading group for DA in WMO together with WGNE. What is future post THORPEX?