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Why the African Initiative needs a research component … and a suggested framework. Mitch Moncrieff Cloud Systems Group NCAR/MMM. African Initiative Workshop, NCAR, July 6-7 2006. Introduction.
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Why the African Initiative needs a research component … and a suggested framework Mitch Moncrieff Cloud Systems Group NCAR/MMM African Initiative Workshop, NCAR, July 6-7 2006
Introduction • During past decades China, and more recently India, benefited immensely from scientific collaboration with the developed nations in weather-climate research, especially numerical modeling & field experiment activities • Africa has yet to benefit to a comparable degree • There is a framework for a research component for the African Initiative based on the following: a) NCAR’s research and modeling infrastructure; b) the international AMMA program
One of Earth’s 3 major convective heat sources, Africa as an integral part of Earth’s climate • Africa’s precipitation regimes are important in the weather context • African monsoon is a unique example of inter-annual variability of climate
Why are convective systems over the U.S. continent and West Africa similar ? Laing and Fritsch (1997) … fundamental role of mesoscale convective systems (Moncrieff & Liu 2006)
Ingredients of the dynamical similarity • Scale-interaction between convective systems and tropical easterly waves (c.f., synoptic waves over US) • Genesis of convective systems in Ethiopian Highlands (c.f., Continental Divide) • Propagating systems in the Tropical Easterly Jet, African Easterly Jet (c.f., westerly shear over US) • Diurnal-cycle convoluted with propagating cloud-systems • Representing mesoscale convective organization in parameterizations for climate models & global NWP models … i.e, Research results for US translate directly to Africa
Solar-heated elevated terrain, convective organization, propagation and shear … Initiation over mountains Far-field propagation Shear: a key organizing effect MCS: a family of cumulonimbus Cumulo- nimbus Mesoscale downdraft Elevated solar heating determines start position & start time of traveling convection Systems travel for 1000’s km
Summertime convection over the continental US simulated (MM5) and compared to radar observations
Simulated precipitation from traveling convective systems NEXRAD analysis (Carbone et al. 2002) Cloud-system resolving model (CSRM) 10-km explicit : no convective param. 10-km: Betts-Miller parameterization
Mesoscsale downdraft latent heating evaporative cooling C Numerical simulation Dynamical model
Upscale evolution of convective organization n n = n + 1 + Dynamic triggering Stage 1: onset Stage 2: multicell families Stratiform heating n n + 1 L n + 2 … Mesoscale downdraft cooling Mesoscale heating & momentum transport Parameterized convective heating Stage 3: mesoscale circulation New hybrid parameterization of convective organization
African Monsoon Multidisciplinary Analysis (AMMA) is a comprehensive international framework Full description: see presentation by Prof. Chris Thorncroft (SUNY/Albany): co-chair, International Steering Committee for AMMA \
African Monsoon Multidisciplinary Analyses • Afrikanske Monsun: Multidisiplinære Analyser • Afrikaanse Moesson Multidisciplinaire Analyse • Analisi Multidisciplinare per il Monsone Africano • Afrikanischer Monsun: Multidisziplinäre Analysen • Analisis Multidiciplinar de los Monzones Africanos • Analyses Multidisciplinaires de la Mousson Africaine
Objectives of AMMA International • To improve our understanding of the West African Monsoon (WAM) and its influence on the physical, chemical & biological environment regionally and globally. • To provide the underpinning science that relates variability of the WAM to issues of health, water resources, food security & demography for West African nations and defining and implementing relevant monitoring & prediction strategies. • To ensure that the multidisciplinary research carried out in AMMA is effectively integrated with prediction & decision making activity.
MODEL LING / FORECASTS Downscaling for impact studies Global SST Teleconnections SATELLITE S Monsoon System GG SST Variability OBSERVATIONS Easterly waves Major River Basins Mesoscale Convective Systems Catchments Vegetation Scale Interactions Convective Cells Pools Water vapor transport Vegetation Trace gas , aerosols, etc EOP SOP LOP A multiscale approach Simulation and dynamical modeling fits here Global 10 km 4 Regional 10 km 3 Mesoscale 10 km 2 Local 10 km 1 Hour Day Season Year
Germany IMPETUS VOLTA France CATCH White Book AMMA-API UK NERC DABEX DODO Others in Europe INTEO, ... EU Integrated Project Pan-african initiative (PIAF) ACMAD USA ARM-DOE NOAA NASA AGRYMET ASECNA CERMES African Univ DMN, DHN, , EIER, others ... 1. AMMA International To reach AMMA aims, need to coordinate -Science (Challenge: disciplines, scales) -Implementation (Obs, Model,..) -Data archive and sharing -Funding issues
ICIG WG2 WG3 WG5 WG1 WG4 ST4Capacity building and training Integrative Science Obs implementation ISSC TT1 Radio soundings WAM & global climate (including aerosol/chemistry) TT2a Surface Layer TT2b Aerosol & Radiation Water cycle TT3 Gourma site TT4 Niamey site Land surface-atmosphere- ocean feedbacks ST3 Database ST1 EOP/LOP TT5 Ouémé site TT6 Oceaic campaigns Prediction of climate impacts TT7 SOP-Dry season Prediction of high-impact weather ST2 incl AOC TT8 SOP-Monsoon season TT9 SOP-Downstream Links with International Programmes (WCRP, IGBP, THORPEX, ..) ARM
Variability in the WAM impacts the US Bonnie (05) Charlie (05) Frances (05) Flooding in New Orleans due to Katrina (courtesy NOAA) Ivan (05) Courtesy A. Aiyyer
In summary … • AMMA – international with strong research and outreach already established after many years of work – Europe, UK & US are major players in the field phase • UCAR-AAAS African Initiative could help AMMA strategic goals that might otherwise be difficult to maintain after the field phase is completed • Research by NCAR scientists and its modeling infra-structure is a contribution to AMMA and potentially to the UCAR/AAAS African Initiative