Report from the PDP working group

1. Report from the PDP working group Craig Bishop, Pat Harr, Shuhei Maeda, John Methven, Mark Rodwell, Istvan Szunyogh, Olivier Talagrand, Heini Wernli including report on status of T-NAWDEX Andreas Dörnbrack, Pat Harr, John Methven, Andreas Schäfler ICSC10 Meeting October 2012

2. PDP mission Main task of the PDP WG: Identify basic research problems with significant importance for NWP and to accelerate the transfer of new techniques from academia to the operational practice. The PDP WG achieves these goals by: Bringing together the academic dynamical meteorology community and the operational NWP centers Encouraging the dynamical meteorology community to carry out process studies with the specific aim to improve the understanding of the relationship between particular processes and weather forecast accuracy.

3. Main activities since ICSC9 5th PDP Working Group meeting at the University of Reading (18-20 June 2012) Cooperation with WGNE (e.g., systematic model error workshop in Exeter in April 2013; diagnostic project on the Indian monsoon) Contributed to the planning of the new Polar Prediction Project and the Sub-seasonal to Seasonal Prediction Project Contribution to ICDM (Int. Comm. Dynamical Met.) meeting in China (summer 2012) Contribution to field campaign activities (DIAMET, HYMEX, T-NAWDEX-Falcon) Launch of simple PDP webpage: http://iacweb.ethz.ch/thorpexpdp Established a linkage with the atmospheric rivers community Input to discussion on legacy of THORPEX

4. PDP webpage: http://iacweb.ethz.ch/thorpexpdp Thanks to Christian Grams!

5. T-PARC TY Sinlaku: Detailed aircraft observations during different stages of TY development Large uncertainty in track prediction prior to recurvature

6. T-PARC TY Sinlaku: New data sets provide detailed examination of structural characteristics e.g., from ELDORA Julian Quinting, Karlsruhe

7. PANDOWAE German PDP-oriented research group (funded by DFG, 2009-2015) All (7) PhD project from first phase completed (now PostDocs at ECMWF, DWD, ETH, U Karlsruhe, U Mainz) 3 “joint papers” (coordinated by PhD student and PI) on overarching aspects of PDP research (Rossby wave trains, diabatic processes, ensembles and adaptivity) About 20 publications so far.

8. Research Area Joint Projects Upper-level Rossby waves Moist processes and diabatic Rossby waves Glatt, I., A. Dörnbrack, S. C. Jones, J. H. Keller, O. Martius , A. Müller , D. Peters, V. Wirth, (2011); Rossby Wave Train Diagnostics: An Intercomparison of Different Methods. Tellus, 63A,991-1006. Grams, C. M., H. Wernli, S. C. Jones, M. Boettcher, J. Campa, U. Corsmeier, J. H. Keller, C.-J. Lenz, and L. Wiegand, 2011: From the extratropical transition of Hanna (2008) to a Mediterranean cyclone: the key role of diabatic processes. Quart. J. Roy. Meteorol. Soc., 137, 2174-2193.. Adaptivity and Ensembles Harnisch, F., D. Anwender, G. C. Craig, S. C. Jones, J. H. Keller, S. T. K. Lang, and M. Weissmann: Evolution of forecast uncertainty before, during, and after the extra-tropical transition of Hurricane Ike (2008): Submitted to Quart. J. Roy. Meteorol. Soc.

9. DIAMET: Diabatic processes in severe weather systems Vaughan / Methven / Renfrew / Parker

10. Observed Uncoupled T159 Coupled T159 D+12–18 T399 Uncoupled T2047 D+5 T399 ERA-Interim mmday-1 20 Wet Monsoon Problem spans all systems and timescales 15 10 Mean monsoon precipitation and errors in July 7 5 3 2 1 20 10 5 2 -2 -5 -10 -20 Milton, Rodwell, Willett, Brown

11. Dynamics Vertical diffusion Effects of modeled processes on wind and humidity Convective precipitation Stratiform precipitation 10ms-1day-1 -20 -12 -4 4 12 20 -20 -12 -4 4 12 20 -10 -6 -2 2 6 10 -10 -6 -2 2 6 10 2ms-1day-1 Unit = 0.1 gkg-1day-1 Understanding the lack of balance between processes (‘spin-up’). A new approach to diagnosis Sum (≈ Increment) Mean July 2009 850 hPa model process tendencies over lead-times 1-13 hrs of 0 & 12 UTC forecasts. Bold: 5% significance

12. Atmospheric Rivers & WISPAR campaign spring 2011 Spackman and Ralph

13. Atmospheric Rivers: Top 10 winter floods in central UK • Top 10 floods in Winter Maximum Series (WMS) over 1970–2010. • Persistent ARs located over basin in these floods. • ARs have consistent location and orientation. Data source: 20th Century / ECMWF ERA-Interim reanalyses. Lavers et al., 2011 GRL

14. T-NAWDEX-Falcon 2012 Andreas Schäfler, Andreas Dörnbrack, Hans Schlager (DLR) Maxi Böttcher, Christian Grams, Heini Wernli (ETH) Partners within PANDOWAE research group

15. T-NAWDEX-Falcon Main objectives • Lagrangian flights during vertical transport in a warm conveyor belt (WCB) with use of in-situ observations (H2O, selected chemical tracers) and dropsondes • Perform a tracer experiment to tag air masses • - release artificial tracer in boundary layer of WCB • collect tracer in WCB ascent and outflow • Investigate latent heating in WCB in warm / mixed-phase cloud and compare with model simulations • Time period: 8-26 October 2012 (i.e., parallel to HYMEX SOP)

16. T-NAWDEX Planning towards a cross-Atlantic aircraft field experiment in 2015 Scientific objective Investigate diabatic processes (e.g., aspects of transport, microphysics and radiation involved in formation of negative PV anomalies at tropopause level) in sequence of North Atlantic weather systems potentially involving ET, extratropical cyclones, WCB & blocking Aircraft Two G-V from both sides of the Atlantic (HIAPER and HALO), shorter range aircraft from UK, … Partners (as of Oct 2012) US (Pat Harr and colleagues), UK (John Methven and DIAMET community), Germany (DLR, U Munich, DWD), Switzerland (ETH), … Procedure: Monthly telecon; submission of US proposal in Jan 2013 (tbc)

17. DACA-13 www.daca-13.org IAMAS & IACS conference 8-12 July 2013 in Davos