AMMA-ALMIP-MEM project soil moisture & μwaves Tb

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1 AMMA-ALMIP-MEM project soil moisture & μwaves Tb P. de Rosnay, A. Boone, M. Drusch, T. Holmes, G. Balsamo, many others ALMIPers (paper submitted to IGARSS) AMMA-ALMIP-MEM first spatial verification of SM/Tbs C-band AMSR-E C-band Tb HTESSEL Result: HTESSEL+CMEM is un-biased and reproduces satellite obs. statistics! Question: What happens in HTESSEL that deteriorates correlation? 1

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3 EARLY FLOOD WARNING IN AFRICA: RESULTS OF A FEASIBILITY STUDIES IN THE JUBA, SHABELLE AND ZAMBEZI RIVERS IN AFRICA Ad de Roo 1, Florian Pappenberger 2, Jutta Thielen 1, Vera Thiemig 1 (1) Land Management and Natural Hazards Unit, Institute for Environment and Sustainability (2) European Centre For Medium Range Weather Forecasts 3

4 European Flood Alert System (EFAS) Added value information for Member States towards preparedness for flood events 3-10 days in advance Development: JRC since 2003 (following major transnational floods in Europe) Support: EFAS DG Env, DG Enterprise, European Parlament, Member States Int. River Commissions 4

5 /23/020:00 8/24/020:00 8/25/02 0:00 8/26/020:00 8/27/020:00 8/28/02 0:00 8/29/02 0:00 8/30/020:00 8/31/020:00 Dessau/Rosslau Wittenberg Torgau Riesa Dresden Labe Decin Labe/Usti N.L. Vltava/Prague INPUT Schematic view of EFAS EU FLOOD GIS Realtime data Histoical data /23/020:00 8/24/020:00 8/25/02 0:00 8/26/020:00 8/27/02 0:00 8/28/02 0:00 8/29/020:00 8/30/02 0:00 8/31/02 0:00 Dessau/Rosslau Wittenberg Torgau Riesa Dresden Labe Decin Labe/Usti N.L. Vltava/Prague Static data Europ. data Meteo Forecasts EFAS reports Expert knowledge from MS 5

6 Pilot study: Transfer of EFAS methodologies to Africa different climatic forcing: large scale, long durations little data and catchment descriptions Two pilots: Juba-Shabelle and Zambezi river basins joined projects with Washington State University (Zambezi) and Somalia Water and Land Information Management (Juba- Shabelle) 6

7 Juba-Shabelle River Basin shared between Ethiopia and Somalia km² Altitudes range from 3000 m to sea level mainly natural vegetation such as riparian forest, bush lands and grasslands, but also swamps in collaboration with Somalia Water and Land Information Management (SWALIM) 7

8 Setting up pilot basins for Africa Topography, soil and land use data available at JRC African Observatory River flow data obtained from Global Runoff Data Centre (GRDC/WMO) and African partners, e.g. SWALIM Weather observations (station and satellite data ) from WMO, Washington State University, ECMWF (European Centre for Medium-range Weather Forecasts), and other sources Weather forecasts: ECMWF archived forecasts and reforecasts for 2 events with state-of-the-art model 8

9 Climate in Juba/Shabelle 2 rain seasons 2 dry seasons 9

10 Longterm High and low river levels 7.00 Bankful level 6.00 Belet Weyne river water Level(m) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec month LT Mean River Levels Flood Year Bank full Level LT Max River Levels LT Min River Levels 10

11 Historical flood years 1961, 1977, 1981, 1997/8, 2005, 2006 Belet Weyne (Shabelle), observed discharge [m³/s] /1/77 7/1/77 1/1/78 7/1/78 1/1/79 7/1/79 1/1/80 7/1/80 1/1/81 7/1/81 11

12 Long-term mean flows for upstream and downstream stations Discharge (m 3 /s) Juba Luuq Jamame Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec upstream downstream Shabelle Belet Weyne Awdhegle Discharge (m 3 /s) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Flow reduction from upstream to downstream: over bank spillage and irrigation diversion -> tuning of hydrological model necessary 12

13 VAREPS forecasts for Africa (Feb-Apr 1978) VAREPS ensembles are being run for the period 15 Feb to 15 Apr 1978 (19 cases have been completed). These forecasts are run in the operational configuration, with model cycle 33r1. ICs are defined by ERA-40. Initial perturbations are scaled larger (γ=0.020 instead of 0.014) than in the operational EPS to take into account the fact that ERA-40 T159 analyses are less accurate than operational T799L91 analyses. These plots show the 19-case average error of the ensemble-mean (blue with symbols) and the std (blue) for T850 over NH (left), Europe (middle) and North-west Africa (12.5S λ 35N, Θ 12.5, left). 13

14 Preliminary results for Shabelle (Belet Weyne) 14 1/1/1976 4/1/1976 7/1/ /1/1976 1/1/1977 4/1/1977 7/1/ /1/1977 1/1/1978 4/1/1978 7/1/ /1/1978 1/1/1979 4/1/1979 7/1/ /1/1979 1/1/1980 4/1/1980 7/1/ /1/1980 1/1/1981 4/1/1981 7/1/ /1/1981 Observations exceed critical threshold Simulations exceed critical threshold

15 15 1/1/1976 4/1/1976 7/1/ /1/1976 1/1/1977 4/1/1977 7/1/ /1/1977 1/1/1978 4/1/1978 7/1/ /1/1978 1/1/1979 4/1/1979 7/1/ /1/1979 1/1/1980 4/1/1980 7/1/ /1/1980 1/1/1981 4/1/1981 7/1/ /1/1981 Preliminary results for Juba (Luuq) Observations exceed critical threshold Simulations exceed critical threshold

16 Summary European Flood Alert System (EFAS) methodologies currently tested for African basins (Zambezi and Juba-Shabelle) Challenge to collect data for set-up, testing and verification First results show that observed meteorological fields have much uncertainty weather forecasts for historic events have limited skills data collection is a challenge flood events can be depicted by the simulations Successful set-up can be used for climate change studies 16

17 For more information: Contacts: Action Leader: Ad de Roo Climate Change: Luc Feyen EFAS: Jutta Thielen 17