WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Example of hydrological modelling Slobodan Nickovic World Weather Research Programme World Meteorological Organization, Geneva with contributions in [B]: G. Pejanovic, M. Vujadinovic, V. Djurdjevic, B. Rajkovic (Belgrade University)

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, HYDRO1k USGS topography HYDROSHED-500m FAO soil texture data USGS land use data DATASETS: HYdrology PROgnostic Model integrated system Example of hydrological modelling Nickovic, et al (2010), HYPROM hydrology surface runoff prognostic model, Water Resour. Res.

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, HYPROM - Full dynamic (FD) equation concept Kinematic approximation neglects inertia forces !!

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Full dynamics (FD) vs. kinematics (KN)  FD model more accurate  FD: friction slope term requires special treatment (Froude number >2)  KN: simplifications avoid problem (Froude number <2)  Most watershed models adapt KN approach  KN cannot accurately represent large-scale, more inert processes

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Kinematic approx Not appropriate for basins with slow slow flows Acceptable for flesh floods (where friction and gradient forces are in approx. balance)  Full dynamic system to be used

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Friction slope Potential source of model instability when FD requires completely different numerical approach to resolve the Instability due to vanishing water heights!

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Friction slope numerics Water depth is in the dominator of friction slope terms Generates numerical instability when depth vanishes Usual approach - water depths to be above a threshold (not a physically-based approach)

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Friction slope numerics – new approach Implicit time scheme applied unconditionally stable method convergent for when then physically based method

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Nickovic, et al (2010) Friction slope numerics – new approach

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Horizontal semi-staggered E grid used the same as the NMM grid problem with gravity wave short wave noise new method to resolve the problem – modification of the continuity equation

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Synthetic sink experiment with HYPROM Without modificationWith modification

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Advection numerics (Janjic, 1997) conserves mass no new extremes no negative values

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, River routing River path: A-B-C-D-E-F Mass conserving River –collector from surrounding points Same numerics as for non-river points

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Savinja case – Oct/Nov 2000 Torrential rain Landslides 7 deaths, quite a damage Complex topography Kobold and Suselj, 2005 Savinja basin

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Savinja case – Oct/Nov 2000 NMM T and V at 850 hPa, 1 Nov 2000 NMM acc. rainfall, 26 Oct – 6 Nov 2000 Savinja basin

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Savinja case – Oct/Nov 2000 River discharge over period 26/10 – 6/

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, Moraca river experiment (Nov 2002 – May 2003) Snow melting case Seasonal-scale run Problem with soil types

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, parameter Clay Loam (09) Bedrock (15) sat. diffusivity0.113 x x sat. conductivity2.45 x x porosity CH constant Sensitivity to soil type

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, model vs. observations discharge 2008 case 2008 water budget components 2008 accumulations

WWRP- GAW INCA-CE 5 th Joint Progress Meeting, Budapest, Hungary, climate studies Bojana river: Buna Bridge discharge