• Climate and Weather Prediction Needs for Africa and • the African Information System Aida Diongue-Niang, Senegal Met.
Download ReportTranscript • Climate and Weather Prediction Needs for Africa and • the African Information System Aida Diongue-Niang, Senegal Met.
• Climate and Weather Prediction Needs for Africa and • the African Information System Aida Diongue-Niang, Senegal Met. Agency, co-chair THORPEXAfrica Pre-technical Conference CASXV Environmental Prediction into the Next Decade 16-17 November 2009 COPT81 Côte d’Ivoire S. Chauzy Climate and Weather Prediction Needs for Africa and the African High-Impact Weather Information System Aida Diongue-Niang, Senegal National Meteorological Agency Co-chair African THORPEX Pre-CAS-XV , Incheon , 17-18 November 2009 2 Variety in ecological zones and mean annual rainfall West African Monsoon Indian Monsoon Strong gradients Climate Prediction Centre (CPC) Africa lies mostly in tropical regions with reversal of wet and dry seasons and in subtropical semi-arid regions Figure 2.2 - Annual total precipitation over Africa. In many parts, the annual rain falls in 3-4 months during the rainy season(s) Onset of the rainy season highly variable, with active & inactive Pre-CAS-XV , Incheon , 17-18 November 2009 phases, particularly in the West African Monsoon region 3 Africa highly vulnerable to climate variability and highimpact weather: Rainfall patterns Fragile ecosystems Weak resilience and adaptation capacity Weak preparedness 60-70% of 922 billions African labour force directly employed by Agriculture, essentially rain-based Pre-CAS-XV , Incheon , 17-18 November 2009 4 Outline • • • • Introduction Rainfall variability and change in Africa High-impact weather in Africa Climate and Weather Prediction Needs in Africa • Data assimilation experiments for AMMA • THORPEX-Africa • HIWIS Pre-CAS-XV , Incheon , 17-18 November 2009 5 Global decrease of rainfall in Africa, particularly the Sahelian Region Rainfall (July-August): Difference between [1967à 98] & [1948 à 66] Pre-CAS-XV , Incheon , 17-18 November 2009 source 6 0-20N, 20W-20E West Africa: High degree of persitence of anamalously wet (e.g. 1930, 1950, 1960) and dry years (e.g 1970s, 1980s) 25S-10S, 20E-40E Variability of the West African Monsoon System with complex feedback mechanisms (atmospheric,,land surface,ocean-e.g. AMO) AMMA programme: www.amma-international.org Climatology 1930-1995 (CRU dataset) Climatology 1979-2055(GPCP dataset) 10S-10N, 20E-50E From Giannini et al, 2008 East Equatorial and Southern Africa: A visible interannual variability •Eastern Africa positively influenced by Warm Enso and SST patterns in the Indian Ocean •Southern Africa negatively influenced by Warm Enso Pre-CAS-XV , Incheon , 17-18 November 2009 7 Rainfall and cereal yields Source UNECA Pre-CAS-XV , Incheon , 17-18 November 2009 8 Rainfall and Runoff Niger Basin Wet Runoff index Rainfall index Dry Factor 2 Pre-CAS-XV , Incheon , 17-18 November 2009 source 9 IPCC AR4 (SRES A1b): Future Rainfall trend in Africa JAS rainfall (2070-99) minus (1960-99) simulated by different climate models Consensus Decrease in Northern & Southern Africa and Increase in Equatorial Eastern Decrease of rainfall in the Sahel Increase of rainfall Sahel Coutesy Redelsperger Pre-CAS-XV , Incheon , 17-18 November 2009 10 AR4 statements in terms of extremes • In the context of global warming, increasing intensity and frequency of extremes • Developing countries highly vulnerable Pre-CAS-XV , Incheon , 17-18 November 2009 11 Outline • • • • Introduction Rainfall variability and change in Africa High-impact weather in Africa Climate and Weather Prediction Needs in Africa • Data assimilation experiments for AMMA • THORPEX-Africa • HIWIS Pre-CAS-XV , Incheon , 17-18 November 2009 12 Main High-impact weather In Africa sS sS sS T Dry spells Tropical cyclones Cyclogenis Flooding Srong winds Sand & Dust Storms Heat waves Frost T T Pre-CAS-XV , Incheon , 17-18 November Daily rainfall (mm) for 1983 rainy season Daily rainfall (mm) for 1998 rainy season Individual MCS developing across West Africa Too many and/or too intense can lead to flash floods and flooding, Too few lead to dry spells and drought Pre-CAS-XV , Incheon , 17-18 November 2009 14 Dust events over northern Africa Biomass burning used as mangement tool across SubSaharan Africa smoke and haze existing off the South-Eastern coast RIVER OF SMOKE MODIS Image – March 2, 2003 Kanyanga, 2003 source Pre-CAS-XV , Incheon , 17-18 November 2009 15 Outline • • • • Introduction Rainfall variability and change in Africa High-impact weather in Africa Climate and Weather Prediction Needs in Africa • Data assimilation experiments for AMMA • THORPEX-Africa • HIWIS Pre-CAS-XV , Incheon , 17-18 November 2009 16 Issues • How to quantify time-evolving African climate changes in order to derive reliable scenarios of human activities? • In the context of climate change how variability at different timescales: decadal, interannual, intraseasonal and weather statistics will be modified? • How can we better improve forecasts of high-impact weather –and its use- that vulnerable societies face day to day Pre-CAS-XV , Incheon , 17-18 November 2009 17 Model Evaluation • Monitoring of global NWP model performance in tropical regions, particularly in Africa, has suffered a relative lack of emphasis, hampering predictability improvements there. • Climate and NWP model evaluation and processes studies to determine model errors that can help to improve models, not enough to partly to lack of crtical mass Pre-CAS-XV , Incheon , 17-18 November 2009 18 errors Africa (JJA) Strong Rainfall link between climateover and NWP model errors GPCP: 1992-2007 NWP 1992: Day 1 - GPCP © Crown copyright Met Office Climate 20Year: NWP 1992-2007: HadGEM2 - GPCP Day 1 - GPCP NWP 2005: Day 1 - GPCP Pre-CAS-XV , Incheon , 17-18 November 2009 From Sean Milton, Met Office 19 Improvement of prediction NWP models Better representation of physical process: Climate models convection, land-surface interactions, aerosols effects, etc Higher resolution (Multi-models) Ensembles Pre-CAS-XV , Incheon , 17-18 November 2009 20 24N 10km20km 20km FEWS 1N 20W 17E 20km BMJ convective scheme Eta 24-48h forecasts accumulated for JAS 2006 Kain-Fritch convective scheme Regional NWP model Strong sensibility to the convective scheme and its coupling to others processes Pre-CAS-XV , Incheon , 17-18 November 2009 21 Diongue-Niang , 2007 Soil moisture impact TRMM Soil moisture from analyses Soil moisture reduced to fit observations Accum. Rainfall oover 24 hours COSMO 2.5 km COSMO 2.5 km Cloud Resolving Model , 17-18 November Standard soil moisturePre-CAS-XV , IncheonModified 22 soil moisture 2009 From Ganther et al. 2009 LMDZ Old Surface OBS Rain JAS From Traore, Fall, et al Diurnal cycle LMDZ New Surface From Traore, Fall, et al Sensitivity to surface scheme n the LMD climate model Pre-CAS-XV , Incheon , 17-18 November 2009 From Sane et al 23 Seasonal Forecasts Results of ECHAM4.5 driven with observed (JAS) and persisted June, May and April SSTAs Skill of JAS Sahel rainfall from GCM (filled) and EOF1 of Low level zonal wind used as predictor for Sahel rainfall After correlation using the wind (open bar) Correlation 0.6 0.5 MOS 0.4 GCM 0.3 0.2 0.1 0 -0.1 -0.2 JAS June May SST boundary conditions Ndiaye, Goddard and Ward, 2009 International Journal of Climatology April Improvement of prediction NWP models Monitoring weather Improving analyses and forecasts Evaluate models Dense network, ReliableTransmission Better initial state Better representation of physical process: convection, land-surface interactions, aerosols effects, etc Higher resolution (Multi-models) Ensembles Climate models Monitoring climate Evaluate models Long term reliable, well distributed data Archiving Observations Better coupling atmosphere-ocean Further understanding, process studies Better representation of teleconnections Biogeochemical processes Pre-CAS-XV , Incheon , 17-18 November 2009 25 GCOS Upper-Air Network (GUAN) and Surface Network (GSN) performance in Africa GUAN performance, 2001 GSN performance, 2001 Pre-CAS-XV , Incheon , 17-18 November 2009 26 Observations network: major constraint to weather to weather improvement Operational temp received at ECMWF Pre-CAS-XV , Incheon , 17-18 November 2009 27 Outline • • • • Introduction Rainfall variability and change in Africa High-impact weather in Africa Climate and Weather Prediction Needs in Africa • Data assimilation experiments for AMMA • THORPEX-Africa • HIWIS Pre-CAS-XV , Incheon , 17-18 November 2009 28 African THORPEX Background 1. 2007-2009: African Science Plan and African Implementation Plan (English & French) produced & distributed to All PRs of African countries leading to about 25 nominated national representatives . 2. Ongoing seek for funding and endorsement 3. A workshop to launch THORPEX Africa Implementation Activities 5-8 October 2009, UNESCO/ICTP, TRIESTE Pre-CAS-XV , Incheon , 17-18 November 2009 29 PDP1: Predictive Skill of high impact weather PDP2: Contributing to the Development of Seamless forecast by filling the gap in intraseasonnal timescales DAOS1: Design of an optimum network in Africa Planned activities Predictability and Dynamical Processes TIGGE Societal and Economic Research Application Data Assimilation observing systems DAOS2: Use of non conventional observing systems Pre-CAS-XV , Incheon , 17-18 November 2009 SERA1: High-impact weather database SERA2: Forecast verification and cost/benefit assessments DAOS3: Improvement of telecommunications facilities 30 PDP1: Predictive Skill of high impact weather PDP2: Contributing to the Development of Seamless forecast by filling the gap in intraseasonnal timescales DAOS1: Design of an optimum network in Africa HIWIS Predictability and Dynamical Processes TIGGE SERA1: High-impact weather database Societal and Economic Research Application observing systems DAOS2: Use of non conventional observing systems Pre-CAS-XV , Incheon , 17-18 November 2009 SERA2: Forecast verification and cost/benefit assessments DAOS3: Improvement of telecommunications facilities 31 Outline • • • • Introduction Rainfall variability and change in Africa High-impact weather in Africa Climate and Weather Prediction Needs in Africa • Data assimilation experiments for AMMA • THORPEX-Africa • HIWIS Pre-CAS-XV , Incheon , 17-18 November 2009 32 Goal and scope of the Information System The ultimate aim of the HIW Information System is to collect HIW events in the past two decades and on going HIW events with a user friendly interface for analysis, processing and visualisation to facilitate integrated and multidisciplinary studies. While seeking for funding, start the activity with an interim prototype database with few recent case studies and simplified interface. This will be used as a pilot demonstration to gather weather, hydrologic, and impact data and undertake predictability and (possibly) socio economic studies. Pre-CAS-XV , Incheon , 17-18 November 2009 33 3 -year demonstration project HIW HIW DATABASE E V E N T S PREDICTABILITY STUDIES Nov.2009-June2010 •Event documentation •Data collection • Metadata generation June 2010-June2011 •Data submission to the database •Forecast Evaluation •Deterministic Model evaluation Jan. 2011-Nov. 2012 Ensemble prediction evaluation High-resolution modelling Process studies Pre-CAS-XV , Incheon , 17-18 November 2009 34 Case studies on flooding events Collaboration&partnership 2008 2009? 2009 2007 UNESCO/ICTP to technically design, host the interim prototype database NHMS (~20) : HIW events analyses and documentation + data submission NWP forecasting centres: contact persons for guidace in model data & diagnostics, model evaluation 1997 Academics: Modelling and 2007? processes studies Other WMO related prog. e.g. WIS, MEDEX MunichRe Geo Risk Research 2008 group: experience sharing, updated review of African HIW from 1990 and in turn more in depth impact data Pre-CAS-XV , Incheon , 17-18 November 2009 35 MunichRe NatCatSERVICE: example Hurricane Ike Affected people Affected buildings Affected infrastructure Affected lines of business Number of deaths Event description From Angelika Wirtz, Munich Re HIWIS HIW HIW DATABASE E V E N T S PREDICTABILITY STUDIES AfRC+NHMS HIW events Af RC ICTP NHMSs Data Submission (weather, hydrology & impact) Academic community +THORPEX Pre-CAS-XV , Incheon , 17-18 November 2009 NWP Centres +TIGGE, JWGFVR 37 01 September 2009 0600 Pre-CAS-XV , Incheon , 17-18 November 2009 38 BURKINA-FASO : OUAGADOUGOU Courteously by Nakoulma Guillaume Concluding remarks on prediction Needs in Africa Climate regime modes Interannual variability mode Seasonal mean anomaly Weather statistics, Wet/dry spells, rainy season onset Weather Regimes Mesoscale, events daily Wkly Mthly Seasonal Yearly Decadal African THORPEX Pre-CAS-XV , Incheon , 17-18 November 2009 40 Thanks for your attention. Questions? Pre-CAS-XV , Incheon , 17-18 November 2009 41 Burkina Faso High Impact Weather Event, Sep 1, 2009, courtesy Wassila Thiaw RFE – 1 Sep 2009 GFS 48h – 1 Sep 2009 GEFS 48h – 1 Sep 2009 X 42 Pre-CAS-XV , Incheon , 17-18 November 2009 Initiation of a MCS Comparaison avec le canal 15 UTC 15 UTC TB (K)IR METEOSAT IR Aïr Aïr Plaine Plaine Squall line over Niger: surface rainfall 22 UTC H Phase Mature 22 UTC H Pre-CAS-XV , Incheon , 17-18 November Diongue et2009 al, 2001 43