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HARMONIE model results for surface wind Gerrit Burgers , Emiel van der Plas , Jan Barkmeijer, … KNMI. The HARMONIE model. High resolution (2.5 km) Numerical Weather Prediction Non-hydrostatic model: Vertical motion (partially) resolved Limited Area (typically 750 km x 750 km)
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HARMONIE model results for surface wind Gerrit Burgers, Emiel van der Plas, Jan Barkmeijer, … KNMI
The HARMONIE model High resolution (2.5 km) Numerical Weather Prediction Non-hydrostatic model: Vertical motion (partially) resolved Limited Area (typically 750 km x 750 km) To be embedded in global (ECMWF) or local (Hirlam) model Developed within the Hirlam/ALADIN consortium HIRLAM model • Current operational KNMI model: Hirlam • 11 km resolution • Performs well, especially for synoptic scale
What do we expect: Improved representation of meso-scale phenomena: Organisation of (individual) thunderstorms Severe phenomena: downbursts, squall lines, … Convergence lines: precipitation that can be intense, but not front-related Prediction of lightning/thunderstorms through association with CAPE and integrated ice/graupel column Better insight in nature of wintery precipitation (snow, freezing rain, etc) … All on a 2.5 km resolution!
10m vs. 140m wind HARMONIE/AROME model (2.5 km grid), March 26, 2009, 04UTC 10m wind 140m wind • sharp land-sea transition in 10m wind field • 140m wind field smooth compared to 10 m wind field
January 1990 storm ERA-Interim vs Harmonie
Case study: Storm Storm Kyrill, 18 January 2007 Fast cyclogenesis Strong winds in Schiphol area (10 Beaufort, gust up to 37 m/s)
Storm 18 jan 2007: wind, gust Wind: Schiphol • Gust:
Case 9 July 2007: convection along coast Strong convection, warm sea, water spouts Formation of a squall line over North Holland
< Harmonie 12:00 UTC Case: convection July 9 2007: precipitation • < Radar • Hirlam > • 12:00 UTC
Case: strong frontal convection, 14 july 2010 Downburst at Vethuizen
Case: 14 july 2010: local • < Radar (1h) • Hirlam 3h acc > • 12:00 UTC • < Harmonie 3h acc • 12:00 UTC
Case: 14 july 2010: wind • < Daily max • Hirlam > • 18:00 UTC • < Harmonie • 18:00 UTC
Case 14 july 2010: boundaries Large differences between Harmonie with Hirlam and ECMWF boundary conditions Study origin of difference in progress Radar Hirlam ECMWF
Outlook Operational implementation of HARMONIE is foreseen for fall 2011 Choice of domain, initial and boundary conditions Data assimilation: Radar data GPS / SEVIRI cloud mask data … Verification module to run on a daily basis Study extractable information Expand methods to conceptual verification: Did an observed and forecasted event meet physical description of e.g. a downburst?
( … )Conclusions HARMONIE performs well in forecasting (strong) convective events (heavy) precipitation (possibly highly localised) strong winds Rain sometimes too intense, localised (to be verified) Domain size of at least 4002 grid points (1000 x 1000 km) is recommended to give resolved results (from cold start) Influence of host model is considerable, under consideration Data assimilation (3D var) appears to vastly improve forecast Meso-scale verification is being set up to study, monitor quality Influence of increased SST is largest in coastal regions, and for systems that originate from over the (North) sea