The Canadian Precipitation Analysis (CaPA) and the Canadian Land Data Assimilation System (CaLDAS)

Transcription

1 The Canadian Precipitation Analysis (CaPA) and the Canadian Land Data Assimilation System (CaLDAS) Vincent Fortin (and many collaborators) Division de la recherche en météorologie Environnement en Changement climatique Canada

2 Outline Current configurations of GEM for (deterministic) numerical weather forecasting CaPA precipitation analysis system 5 years of operational precipitation analyses Changes in latest upgrade High-resolution configuration Current development priorities Data access Literature review Overview of the CaLDAS land data assimilation system Page 2 December-5-16

3 GEM forecasting system

4 GEM deterministic forecasting systems GDPS: Global 25-km / 240-h forecasting system Page 4 December-5-16

5 GEM deterministic forecasting system RDPS: North American 10-km / 84-h forecasting system Page 5 December-5-16

6 GEM deterministic forecasting system HRDPS: Canadian 2.5-km / 48-h forecasting system Page 6 December-5-16

7 Canadian Precipitation Analysis: real-time QPE for Canada Optimal interpolation technique used to merge gauges, radar and satellite data with a background provided by the GEM RDPS model Fully automated quality control 6-h and 24-h accumulations 10 km horizontal resolution Early (T+1h) and late (T+7h) analyses Last 30 days of data available on ECCC's websites and Geomet WMS viewer Page 7 December-5-16

8 Typical network of stations assimilated in 6-h product Page 8 December-5-16

9 CaPA versions More details can be found here: Implementation date Version name Résolution Info additionnelle 2018 REPA km Ensemble of 20 precipitation analyses 2017 HRDPA km Increase in horizontal resolution Nov 09, 2016 RDPA km Assimilation of U.S. radars near the Canadian border and additional Network of Networks observations in B.C. and Ontario Dec 15, 2015 RDPA km Minor bug fixes Jun 03, 2015 RDPA km Nov 18, 2014 RDPA km Aug 20, 2013 RDPA km Page 9 December-5-16 Improvements to QC procedure for solid precipitation Assimilation of Doppler radar rainfall retrievals from Canadian radars Minor bug fixes and improvements to the code structure Oct 03, 2012 RDPA km Increase in horizontal resolution Jan 31, 2012 RDPA km Minor bug fixes Apr 06, 2011 RDPA km First implementation focusing on the assimilation of ECCC weather stations, as well as cooperative networks in the U.S. and Quebec

10 RDPA 4.0 Assimilation of two new networks: BC Forest: 228 stations Ontario MNRF: 60 stations Assimilation of zero precipitation reports from METAR network in the USA: ~500 reports on average over the USA Assimilation of 30 US radars near the Canadian border BC Forest OMNRF Assimilated radars Page 10 December-5-16

11 HRDPA 4.0 Same code base as RDPA 4.0 GEM HRDPS 2.5 km model background Assimilation of additional data from BC Transportation (~60 stations) and CoCoRaHS (~110 stations available at synoptic hours) Already in production, but will have experimental status until the HRDPS is declared operational in 2017 Experimental outputs already available in real-time through the RPN-WMS server and Adaguc WMS viewer Page 11 December-5-16

12 CaPA HRDPA animation, 24h totals, Z to Z Animation created on Page 12 December-5-16

13 Current Development Priorities Ensemble of precipitation analyses Continuing to incorporate NoN station data Satellite data assimilation (GOES-R, IMERG/GPM) Global precipitation analysis 3-h accumulations (goal: 1-h) Hourly updates (instead of every 6-h) Improving QC for solid precipitation (including realtime bias corrections) 30-year hindcast Page 13 December-5-16

14 Wind-induced undercatch for dry snow crystals: hopeless? Rasmussen et al. (2014), OMM/TECO Page 14 5 décembre 2016

15 Vision for improving CaPA in winter: dealing with wind undercatch Ensure that the main parameters required for real-time correction of automatic measurements are available 2-m wind speed temperature, humidity precipitation phase Maintain a reference network of (nearly-) unbiaised measurements under radar range Page 15 December-5-16

16 Precipitation in reanalyses Time series of global monthly mean precipitation for MERRA, ERA-Interim, ERA-40 and GPCP (Rienecker et al. 2011) Page 16 December-5-16

17 Methodology ERA-Interim: 1979 to today (~80km/6h) GEM GDRS (50 km) atmospheric model GEM RDRS (15 km) atmospheric model Precipitation and surface data assimilation: CaPA and CaLDAS GEM-Surf (50 km) surface model Initialisation + forcing Surface observations Initialisation Assimilation Page 17 December-5-16

18 Summer: 24h Precipitation Accumulation ERA-Interim vs. GDRS vs. CaPA analysis FBI ETS FBI = 1 is better Higher is better Page 18 December-5-16

19 The Canada Land Data Assimilation System (CaLDAS) IN Ancillary land surface data Orography, vegetation, soils, water fraction,... Atmospheric forcing T, q, U, V, Pr (CaPA), SW, LW Observations Screen-level (T, Td) Surface stations snow depth L-band passive (SMOS, SMAP) MW passive (AMSR-E) Optical / IR (MODIS, VIIRS) Combined products (GlobSnow) GEM Surf OBS CaLDAS y x b ASSIMILATION EnKF + EnOI EnKF x a = x b + K { y H(x b ) } with K = BH T ( HBH T +R) -1 OUT Analyses of Surface Temperature Soil moisture Snow depth or SWE Vegetation

20 The CaPA/CaLDAS/HRDPS connection 6 hours 6 hours CaPA CaPA... CaLDAS CaLDAS CaLDAS CaLDAS... HRDPS cycle HRDPS cycle... HRDPS cycle hours

21 Surface model Tiles found on each grid point: glacier lake ice open water urban areas (optional) land tiles (SVS) bare ground low vegetation or small lake model tall vegetation Single liquid water content profile under the three land tiles but different temperature profiles near the surface Page 21 December-5-16 glacier ground ice water urban low veg high veg

22 SVS

23 CaLDAS-HRDPS soil moisture analysis (still using ISBA at this point)

24 ISBA SVS NLDAS NOAH NLDAS MOSAIC