1 / 15

Intensification of the water cycle: Regional Aspects

Intensification of the water cycle: Regional Aspects. D. Lüthi, S. Kotlarski, J. Schmidli, P. Pall, E. Fischer, E. Zubler, L. Schlemmer , W. Langhans , O. Bellprat, J. Arnold, J. Rajczak and C. Schär. Overview. Analysis of ENSEMBLES Data Role of aerosols

yeriel
Download Presentation

Intensification of the water cycle: Regional Aspects

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Intensification of the water cycle:Regional Aspects D. Lüthi, S. Kotlarski, J. Schmidli, P. Pall, E. Fischer, E. Zubler, L. Schlemmer, W. Langhans, O. Bellprat, J. Arnold, J. Rajczak and C. Schär D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  2. Overview • Analysis of ENSEMBLES Data • Role of aerosols • Plans for European scale simulations • Activities in convection resolving modeling D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  3. ENSEMBLES RCMs, x1d.5_SON (1971-1998), relative model bias [%] Courtesy J. Arnold D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  4. Change in Extreme Precipitation Events for Alpine Region from ENSEMBLES transient RCM Projections • IMPORTANT RESULTS • Spatially diverse changepatternsforprecipitation in themid 21st centuryacross Alpine region. Remarkabledifferencesbetween northern and southern Alps. • Increaseofextremes in northern Alpine regions in winterandmostnotably in fall. • Decreaseofmeanprecipitationandfrequency in summerandspringacrossentire Alpine region, mostpronounced in theSouth. Example: Extreme precipitation in Fall (SON) Spatial distribution of change for 1-day precipitation extremes with a return value of 5 years in Fall (SON). Ensemble-median over 10 RCMs. Change of basic statistic & extreme diagnostics in the NE-Alpine subregion in Fall (SON). Courtesy J. Rajczak D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  5. Apparent temperature > 105°F/40.6°C Changes are strongest over humid and warm regions (coasts and river basins) Courtesy E. Fischer

  6. Altitude dependence of climate change signal Courtesy S. Kotlarski D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  7. Simulation with explicit Aerosol treatment - ERA40 boundary conditions • The cloudradiativeforcingshows negative trends • Enhancementofcloudforcingcanbepartlyexplainedwithdecreasedtroposphericabsorption • All-skyconditions: Effectofaerosolsisreduced in someregions due tocloudeffects (e.g. British I.) • Strongest all-skysignal: Mid-Europe (roughly 5 Wm-2increase) Courtesy E. Zubler

  8. Plans for European Scale simulations • Simulations in the framework of IPCC-CORDEX:Scenarios RCP4.5 and RCP8.2 for a CMIP5-GCM for period 1950-2100 with a resolution of 12.5 km • 2 more CMIP5-GCM runs will be downscaled in the CLM-community • Several tests for configuration choice have been performed. • PhD work of Omar Bellprat to develop an objective method for model tuning • Special process studies, like influence of snow cover etc. Courtesy K. Keuler D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  9. Perturbed physics and numerics ensembles • Evaluation of model parameter uncertainty • Comparison to uncertainty from internal variability • Evaluation of annual cycle, interannual variability and extreme statistics • Testing performance frameworks • Identify important model parameters Courtesy O. Bellprat

  10.  = 25 km  = 2.2 km Kilometer-scale modeling • Currently • used in operational weather prediction • used for climate process studies, investigations of numerical settings and idealized simulations • under development for climate scenarios • Target: • First use for scenarios within next year (Hohenegger et al. 2008, 2009Jürg Schmidli, Wolfgang Langhans, Linda Schlemmer, ETH Zürich)

  11. Idealized simulations: role of stability • what are the key parameters to characterize moist convection • idealized simulation with flat terrain and periodic boundaries • horizontal resolution 2.2km Courtesy L. Schlemmer D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  12. Kilometer scale modeling: planned activities • Nested 12km and 2.2km runs with ERA-interim boundary data for the 12km simulation • evaluation of simulations vs. observations • evaluate added value from high resolution for Alpine area (precip statistics) • if necessary, adjust configuration and rerun evaluation run • run (10-30yr) time-slice simulations with GCM boundary data for present and future climate • contribute to task1 of HP2C project D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

  13. Thank you for your attention

  14. Health risk and population density Source IIASA Fischer and Schär (2010) Courtesy E. Fischer

  15. altitude dependence of climate change signal Alpine region difference period 1960-1990 vs. 2070-2100 Courtesy S. Kotlarski D.Lüthi et al.: Intensification of the water cycle - Regional Aspects

More Related