investigating the west african climate system using global/regional climate models

583APRIL 2002AMERICAN METEOROLOGICAL SOCIETY |

three-day workshop took place at HowardUniversity in Washington, D.C., from 27 Julythrough 29 July 2000 to examine scientific and

social issues associated with climate research in WestAfrica. This workshop was funded by the NationalScience Foundation’s (NSF) International and Atmo-spheric Science programs. It was hosted by facultymembers from the Pennsylvania State University’sDepartment of Meteorology and the Howard Univer-sity Center for the Study of Terrestrial and Extrater-restrial Atmospheres (CSTEA) and Graduate Pro-gram in Atmospheric Sciences. West African scientists

were represented from Senegal, Cameroon, Niger,Nigeria, Botswana, and Zambia. American scientistsfrom a host of university and research settings werealso participants in this workshop (Fig. 1).

BACKGROUND AND RATIONAL FOR THEWORKSHOP. West Africa has experienced adownward trend in rain amounts during its wet pe-riod (May–October) over the past 30 yr (Nicholsonet al. 2000). While a primary cause for reduced rain-fall has not been found, West Africa climate variabil-

Investigating the West African Climate SystemUsing Global/Regional Climate Models

BY GREGORY S. JENKINS, ANDRE KAMGA, ADAMOU GARBA, ARONA DIEDHIOU,VERNON MORRIS, AND EVERETTE JOSEPH

A three-day workshop at Howard University examined scientific and social issues

associated with climate research in West Africa. Climate variability land-use,

climate change, and capacity building were discussed.

AFFILIATIONS: JENKINS—Department of Meteorology, ThePennsylvania State University, University Park, Pennsylvania;KAMGA—UCAR Visiting Scientist, NCEP-African Desk, CampSprings, Maryland; GARBA—EAMAC School of Meteorology,Niamey, Niger; DIEDHIOU—IRD-LTHE-ENSHMG, Grenoble,France; MORRIS—Atmospheric Sciences Program andDepartment of Chemistry, Howard University, Washington,D.C.; JOSEPH—Atmospheric Sciences Program, and Departmentof Physics, Howard University, Washington, D.C.CORRESPONDING AUTHOR: Gregory S. Jenkins, Departmentof Meteorology, 503 Walker Building, The Pennsylvania StateUniversity, University Park, PA 16802E-mail: [email protected]

In final form 1 October 2001©2002 American Meteorological Society

FIG. 1. American and West African scientists listen to apresentation at Howard University.

A

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ity has been shown to be related to anomalous Atlan-tic or global sea surface temperature (SST) anomalies,and the interdecadal trend in Northern and South-ern Hemisphere SST anomalies (Lamb 1978; Palmer1986; Rowell et al. 1995). Furthermore, model stud-ies indicate that land-use change can reduce rainamounts in West Africa (Charney 1975; Xue andShukla 1993; Zheng and Eltahir 1998; Wang andEltahir 2000). Anomalous atmospheric circulation hasalso been associated with negative precipitationanomalies during the main rainy season (Lamb andPeppler 1992; Newell and Kidson 1984). In additionto climate variability and land-use change there is thepotential for changes in the mean climatic state ofWest Africa from anthropogenic greenhouse forcing(Jenkins et al. 2002). Global climate models (GCMs)and regional climate models are good tools for under-standing how each factor can impact the regional cli-mate of West Africa. However, before any conclusionscan be drawn from climate model sensitivity studies,the simulated mean state and the intraseasonal vari-ability of the West African wet season must beevaluated.

There are several atmospheric features during theWest African rainy season that must be correctlysimulated in order to have confidence in GCM sensi-tivity studies related climate variability or climatechange. One feature, the 200-mb tropical easterly jet(TEJ), originates in India and is associated with re-duced (enhanced) rain amounts in West Africa whenit is weaker (stronger) than normal. Another feature,the 700–600-mb African easterly jet (AEJ), is drivenby the north–south thermal gradient of surface tem-peratures in West Africa (Cook 1999) and is associ-ated with reduced (enhanced) rain amounts when itis stronger (weaker) than normal (Newell and Kidson1984). This means that the surface temperature gra-dient in West Africa as well as the upstream condi-tions over India must be simulated correctly. Finally,GCM data are used to drive regional climate modelsimulations at the lateral boundaries and should com-pare favorably to observations or poorly simulatedregional climate simulations will result because ofsystematic lateral boundary errors (Jenkins andBarron 2000).

There are social factors affecting West African sci-entists that demand examination, discussion, and re-flection. The scientific career of the West Africanscientists may be influenced by various social–economic–political factors that are unlikely to be ex-perienced by their counterparts in the United States.The most likely outcome of these various factors is iso-lation from the rest of the scientific community. This

negative impact is greatest to the individual scientist,West African universities, or laboratories, but is alsofelt in the larger community. New ideas, theories,methods, and insights may never reach the largercommunity. This workshop aimed to increase theawareness of these various social–economic–politicalfactors while seeking ways to increase U.S.–WestAfrican collaboration.

The goal of this workshop was to provide a forumfor participants to discuss critical issues of climatevariability and climate change in West Africa and tostimulate collaboration between West African andAmerican scientists.

The specific objectives of this workshop were asfollows:

• to discuss current and cutting-edge issues in theatmospheric sciences as they relate to the West Af-rican climate system,

• to examine the ability of global/regional climatemodels to capture the mean characteristics of theWest African climate system with particular em-phasis on the wet season,

• to examine and discuss the strengths and limita-tions of the various data sources available for modelvalidation,

• to formulate strategies for overcoming barriers thatlimit research and capacity building in WestAfrica,

• to develop collaborative working groups of WestAfrican and American scientists for pursuing re-search topics,

• to discuss new techniques and areas of research forclimate studies in West Africa (e.g., Web-basedcollaboration, ensemble modeling, downscalingtechniques, and hydrologic modeling), and

• to discuss how the output of global/regional climatemodels can be applied to other disciplines or forparticular applications (e.g., water resource manage-ment, agriculture, and sustainable development).

The meeting opened with welcoming addressesfrom Dr. Don Coleman, provost of Howard Univer-sity; Pat Tsuchitani, of the International Division atNSF; and the two cohosts of the workshop, Dr.Vernon Morris, deputy director of the CSTEA andassociate professor of chemistry, and Dr. Gregory S.Jenkins, assistant professor of meteorology at ThePennsylvania State University.

Following the welcoming addresses, there was atribute to the late Dr. Siemon Fongang, who suddenlybecame ill and died in January 2000, and his effortsat the Laboratory for Atmospheric Physics (LPA),


Cheik Anta Diop University Dakar, Senegal. Dr.Fongang, who was born in Cameroon, possessed atrue sense of integrity, vision, creativity, ingenuity,and adaptability in order to maintain a first-rate labo-ratory and served as a positive role model for manyWest African students who studied at LPA and formany outside of LPA. Dr. Fongang was knownthroughout the continent of Africa in the disciplineof atmospheric sciences and collaborated with numer-ous researchers in Europe.

Dr. Amadou Gaye of LPA (Fig. 2) summarized thetypes of research activities in LPA that had been ini-tiated by Dr. Fongang including:

1) rainfall estimation by radar and satellite;2) dynamics and climatology of West African climate;3) study of convective systems, including mesoscale

convective system (MCS) trajectories, MCS be-havior (decay, genesis, lifetimes, diurnal effect),interactions with synoptic systems like easterlywaves, influence of monsoon, topography, andocean;

4) water vapor climatology (satellite data and models);5) monsoon variability in West Africa;6) model validation and predictability of West Afri-

can climate;7) ocean–atmosphere interactions;8) numerical simulations; and9) aerosols and atmospheric pollution.

In June 1999, Dr. Fongang and LPA hosted theWest African Monsoon and Prediction (WAMAP)international meeting in Dakar, Senegal. TheWAMAP meeting was sponsored by the NationalScience Foundation (NSF), the National Oceanic andAtmospheric Administration (NOAA), the WorldMeteorological Organization (WMO), and theAmerican Meteorological Society (AMS). The meet-ing focused on theoretical, simulated, and observa-tional aspects for various spatial–temporal scales ofthe West African monsoon system. Participants camefrom West Africa, Europe, and the United States. Theideas, interactions, and spirit of the WAMAP meet-ing and the tireless effort of Dr. Fongang served as asource of motivation for the workshop at HowardUniversity.

WORKSHOP SESSIONS. GCM simulations of themean climate state of West Africa. The purpose of thissession was to examine the mean state andinterannual variability of West African climate invarious GCMs and the NCEP reanalysis. A topic dis-cussed in this session is the common problem in

many GCMs of accurately simulating the rainfallmaximum just off the coast of West Africa. The mostlikely cause of poorly simulated rain is due to thesmoothing of orography (Guinea Highland). Further,the GCMs inability to properly simulate stratiformrain could also be a source of error. Other presenta-tions included the underlying causes for the struc-ture of simulated precipitation in West Africa, simu-lating interannual and interdecadal trends ofprecipitation anomalies, and simulating the annualcycle of rain in West Africa and its subregions(Guinea, Sahel). A sample of presentations in this ses-sion include the following: A Comparison of Precipi-tation Processes over West Africa in the NCEP Re-analysis and a GCM (Dr. Kerry Cook), InterannualVariability of the West African Monsoon in theNCEP/NCAR Reanalysis II (Dr. Wassila Thiaw), andCirculation and Rainfall Variability over West Africaas Simulated by the ECHAM 3.6 Forced with Ob-served SSTs 1950–99 (Dr. Neil Ward).

GCM simulations–analysis of easterly waves. A major fea-ture of the West African climate system on dailytimescales is the easterly wave (Burpee 1972). Easterlywaves have typical wavelengths of 2000–2500 km, life-times of 2–5 days, and serve as important rain-bearingsystems. Easterly waves are associated with baroclinicand barotropic exchanges of energy as they track west-ward from continental to oceanic areas (Norquistet al. 1977). They are also associated with tropical dis-turbances (depressions, storms, hurricanes) especiallyduring the latter part of the wet season. It is still un-clear what role easterly waves may play in future climatechange (Druyan et al. 1999). Furthermore, there arethe 6–9-day waves that have been identified in West Af-rica that might affect convection (Diedhiou et al. 1999).

FIG. 2. Dr. Gaye of LPA describes the work of the lateDr. Fongang.

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Presentations in this session focused on 1) ECMWFanalysis and NCEP reanalysis representation of east-erly waves, 2) wavelet analysis for examining changesin the wave activity during the rainy season and 3)GCM simulations of easterly waves from an Atmo-spheric Modeling Intercomparison Project (AMIP)simulation. Accurately simulating easterly waves inGCMs is important because they represent a signifi-cant fraction of the internal variability in the WestAfrican climate system (Fyfe 1999). Moreover, east-erly waves probably play a direct or indirect role inthe interannual variability of rainfall (Druyan 1998).In regional climate model simulations over West Af-rica, easterly waves propagate through lateral bound-aries and have a direct bearing on the simulation(Jenkins 1997; Druyan and Fulakeza 2000). A sampleof presentations in this session includes the follow-ing: Spectral Wavelet and Filter Analysis of AfricanEasterly Waves (Dr. Andre Kamga), Evidence of East-erly Wave Activity in the Community Climate Model(Dr. Gregory Jenkins), and GCM Simulations–ECMWF Analysis–NCEP Reanalysis of EasterlyWaves (Dr. Arona Diedhiou).

Mesoscale–regional climate model simulations of east-erly waves and/or squall lines in West Africa. Mesoscalemodel simulations offer the potential to increase ourunderstanding from GCM studies on the topics ofintraseasonal, interannual, and interdecadal variabil-ity, land-use change, and climate change. Mesoscalemodels can resolve orographic features, lakes, coast-lines, and sharp gradients in vegetation, temperature,and soil moisture better than GCMs. Moreover, me-soscale models can resolve the synoptic-scale easterlywaves and apply appropriate physical parameteriza-tions to mesoscale features.

While easterly waves are the primary synoptic fea-ture during the rainy season, mesoscale convectivesystems (MCSs) in the form of squall lines (Fortune1980; Rowell and Milford 1993) or mesoscale convec-tive complexes (MCCs) (Laing and Fritsch 1993;Hodges and Thorncroft 1997) are frequently associ-ated with easterly waves and responsible for a signifi-cant fraction of the total rain in West Africa (D’Amatoand Lebel 1998). In this session, mesoscale simulationsfrom four different mesoscale models using grid spac-ing that ranged from approximately 5–150 km werepresented. The timescales represented in these simu-lations ranged from days through seasons. The simu-lations were driven at the lateral boundaries byECMWF analyses, NCEP reanalysis, and GCM out-put. In simulating squall lines, high-resolution simu-lations (<20 km grid spacing) using ice physics were

presented. A sample of presentations in this sessionincluded the following: Limited Area Model (LAM)Simulations of a Squall line Associated with an Afri-can Easterly Wave (Dr. Mariam Diop), The Influenceof SST Anomalies on West Africa Precipitation in aMesoscale and a Global Climate Model (Dr. E. Vizey),Initiation of an African Squall Line and its Interactionwith the Large-Scale Environment (Dr. Aida Diongue),and Regional Climate Model Analyses of Phenomenaover West Africa (Dr. Matthew Fulazeka).

The interplay between chemistry and climate: Issues inchemical meteorology. Chemical measurements andmodeling in West Africa have been ignored for themost part with the exception of a few field experi-ments. In West Africa, biomass burning occurs fromNovember through April leading to the productionof aerosols and indirectly to tropospheric ozone.Aerosols and tropospheric ozone have the potentialto affect both the longwave and shortwave radiationand therefore regional climate. Marufu et al. (2000)estimates that biomass burning emissions produce 9%of the total tropospheric ozone. Africa represents thelargest contribution to the production of troposphericozone accounting for approximately 35% of the totalthrough biomass burning. In this session, the severalpresentations examined the key chemistry—climatequestions for West Africa (Fig. 3). Dr. Anne Thomp-son discussed the production of ozone through bio-mass burning, NOx production from lightning, aero-sol transport and radiative forcing, and results froma recent ship experiment in the tropical Atlantic(Thompson et al. 2000).

From November through March when biomassoccurs in West Africa, some of the constituents arelikely transported equatorward toward deep convec-tion. The vertical transport of these constituents canlean to the production of ozone in the tropical Atlan-tic. However, there are many open questions aboutthe vertical transport of ozone and ozone precursorsfrom the planetary boundary layer into the free tro-posphere (Jonquieres et al. 1998). A number of thesequestions related to transport and the production ofozone can be answered only through direct measure-ments (Logan 1999). If ozonesonde measurementscan be obtained just downwind of the biomass fire inWest Africa, it would link chemistry to meteorologyand climate regional scales.

Data limitations and validation of GCM–mesoscalemodels. The objective of this session was to discuss thevarious data needs for GCM and regional climatemodel studies with respect to West Africa. The dis-


cussion included spatial and temporal scales of ob-served data, availability, and cost of observed data.

GCM STUDIES. For GCM studies there was a consen-sus that observed data with a minimum spatial scaleof 2.5° latitude × 2.5° longitude was sufficient for com-parison and validation. However, the temporal scale forvalidation could vary from monthly to daily timescalefor examination of easterly waves in the GCMs.

REGIONAL CLIMATE MODEL STUDIES. For regional climate orlimited area modeling studies there was a generalagreement that global analyses and observational dataon relatively short timescales (3–12-h temporalresolution) were needed for initialization, updating lat-eral boundary conditions, and verification of modelsimulations. For the initialization and boundary con-ditions the NCEP reanalysis or ECMWF analyses aregenerally interpolated to the regional model grid spac-ing. However, in order to verify model simulations, sta-tion reports (surface and upper air) for West Africaare needed. The most likely source of station data isthe National Climatic Data Center (NCDC). However,the benefits associated with station data that wouldmake West African–U.S. collaboration a viable alter-

native to offset the data costs. There is also station dataavailable for the 1987–95 period from NCEP and Hy-drologic Atmospheric Pilot Experiment (HAPEX)–Sahel data for the 1992 period. Satellite data at 30 minto daily timescales are a critical source of informationfor squall line and easterly wave studies and can be usedfor identifying and analyzing evolving MCSs. Satelliteimages can be compared to simulated regional climatemodel precipitation and cloud fields. Geostationarysatellite data are available from the EuropeanOrganisation for the Exploitation of MeteorologicalSatellites in Germany.

OTHER ISSUES RELATED TO OBSERVED DATA. Access to data.The researchers at the workshop were interested instation data, the NCEP reanalysis, and the ECMWFanalyses for their research interest. Station data fromWest Africa are often difficult to obtain because it canbe considered a “natural resource.” Moreover, it maytake personnel to retrieve archived data leading toadditional cost. In order to study the large-scale cir-culation or synoptic-scale features such as easterlywaves, access to gridded analyses (ECMWF or NCEP)are necessary. The ECMWF analyses are not freelyavailable to many West African researchers. TheNCEP reanalysis are generally free, but several re-searchers in West Africa found that there was a chargefor downloading the data via the Web. There are alsosome costs associated with having the NCEP datashipped to Africa on CD-ROM.

Availability of data over the Web, and Internet capa-bility of West African institutes. Accessibility to dataover the Internet is the most feasible way for WestAfrican researchers to obtain data for research pur-poses. However, a stable Internet platform that allowsfor the transfer of data over extended periods of timeis necessary. Therefore, it is mandatory that theInternet capability is reliable in West African researchlaboratories or departments if U.S.–West African col-laboration has any chance of being sustained for thelong term.

Understanding and overcoming barriers that inhibit pro-ductive research for West African scientists. In this ses-sion, there was dialogue between the West Africanparticipants and the rest of the group to discuss thevarious obstacles that researchers in West Africa mayencounter. This discussion was broken up into a num-ber of pragmatic issues, which follow.

CRITICAL MASS. The number of West African scientistsactively researching some aspects of the climate sys-

FIG. 3. Dr. Anne Thompson of NASA Goddard SpaceFlight Center lectures on a recent ship campaign in thetropical Atlantic.

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tem (atmosphere, ocean, biosphere) is relatively smalland they are situated in various countries (based ondiscussions and the number of published authors). Inthe atmospheric sciences, only a small number ofWest African institutions of higher learning producegraduate or undergraduate degrees in meteorology.In particular there is the LPA in Dakar, Senegal, whichis a research laboratory where graduate students com-plete their Ph.D. work. There is also L’Ecole Africainede la Météorologie et de l’Aviation Civile (EAMAC)school of meteorology in Niamey, Niger that providesB.S. degrees in meteorology. There may be severalschools in Nigeria that have an emphasis in the atmo-spheric sciences but offer degrees in other majors (ge-ography for example).

OPPORTUNITIES FOR PH.D. RECIPIENTS. Because of thesmall number of institutions of higher learning thathave programs in the atmospheric sciences in WestAfrica, there are not many opportunities for recentgraduates with Ph.D. degrees in West Africa. Thismeans that West African scientists are left with fewoptions including 1) working at an operational me-teorological center in West Africa, 2) fleeing one’scountry to find opportunities at universities in othercountries (Africa or elsewhere), or 3) serving as aperpetual postdoc in Europe, Canada, or the UnitedStates for numerous years until another opportunitypresents itself. This raises an important question: Is aPh.D. in the atmospheric sciences a viable option foraspiring students in West Africa? There were severalresponses: 1) atmospheric science institutions (uni-versity departments, centers) in West Africa shouldundertake research projects that have a practical ap-plication so that the work can be perceived as usefulto a particular country in the eyes of the government;2) while applications are useful, the field of atmo-spheric sciences is not solely based on applications,but includes observation, experimentation, theory,and simulations—by considering only applications,West African scientists are excluded from makingimportant contributions and pushing the disciplineforward; and 3) there should be an effort to build ca-pacity in West African institutes of higher learning,which would allow for research with practical applica-tions and basic research while also providing for theeducational needs of tomorrow’s scholars in WestAfrica.

This discussion raised other relevant issues. First,some participants felt that there is a perception thatWest African scientists lack the basic skills for under-taking research and therefore must be trained in Eu-ropean or American institutions. This false percep-

tion has existed for some time, but in reality a majorproblem is the lack of internal and external resourcesdirected toward the education process in West Africa.The presentations by West African researchers gavesome indications that cutting-edge research projectsare being pursued helping to eliminate any false per-ceptions among the U.S. workshop participants.Second is the question of why there are so few gradu-ate atmospheric science programs in West Africa.One view was that due to colonialism, meteorologistswere trained mainly for observation and not neces-sarily for undertaking independent research. Thiscreated an imbalance and stunted the development ofresearch institutes in West Africa. Ultimately, opera-tional meteorological centers were considered as thefocal point of activities. A similar pattern occurred inthe United States at historically black colleges anduniversities (HBCUs). These institutions were slatedfor pedagogy and not research from their inceptionthrough to the Civil Rights movement of the 1960s.Special efforts were necessary to change this originalmission statement to one that considers research asan important activity in HBCUs.

It is important to identify the factors that are criti-cal for sustaining a graduate program/department. Asolid academic program with a strong research com-ponent that is recognized for scientific excellence at-tracts good students, faculty, and researchers.Presently, there are very few departments/programsin the atmospheric sciences in West Africa that havea global reputation for producing large quantities ofscholars or publishing scholarly research and thathave excellent facilities for sustaining research. In theUnited States, HBCUs have focused on capacity build-ing as a strategy for sustaining long-term research.Similarly, atmospheric science programs in West Af-rica can capacity build for long-term sustainability,but they need help from internal and external sources.

COMMUNICATION. Reliable mediums of communicationmust exist in order for individual or institutional col-laborative research to effectively take place. TheInternet offers the best possibility for communicat-ing ideas and results between research partners. Whilea number of West African universities have Internetcapability (e-mail, ftp, World Wide Web) many haveonly limited Internet capacities such as e-mail.Limited Internet capacity inhibits collaborative re-search, since scientific activities that involve largequantities of data cannot be shared easily with WestAfrican colleagues. Hence, at the beginning of thetwenty-first century a major obstacle to collaborationbetween U.S. and West African scientists is the modes


of communication. Thus on some scale, capacitybuilding must include increasing and enhancingInternet capabilities in West African institutions. Asecond obstacle to collaboration is language. This ar-tifact from colonialism can inhibit collaboration be-tween West African scientists from francophonecountries and scientist in the United States. It can alsoreduce the amount of collaboration between WestAfrican scientists from anglophone and francophonecountries.

INTERINSTITUTIONAL CHALLENGES. Because of limited re-sources, tension can arise between the traditional me-teorological centers and atmospheric science depart-ments in West Africa. Creative measures should betaken to ensure that there are ample opportunities forboth groups to interact with each other on variousscales. For example, operational meteorologists anduniversity researchers can work on various projectsas team members and publish the results. Operationalmeteorologists can take additional courses or help todevelop new courses because of their experience atmeteorological centers, thereby aiding both commu-nities. Students, faculty, and operational meteorolo-gists can take part in field experiments promoting newknowledge for the global community.

PERCEPTION OF UNIVERSITY RESEARCH IN WEST AFRICA.Weather forecasts have an obvious application andbenefit to the short-term conditions that face a givensociety. This is usually not the case when consideringthe research that is done at a university. While thereare benefits and applications from research it usuallyoccurs on a longer timescale for developed or devel-oping countries. This perspective should be clarifiedso that funding government agencies can see the uni-versity department as an asset for developing futurescholars and as a facility for investigating scientificproblems that are of interest to West Africa or theglobal community.

Parallels between West Africa institutes and historicallyblack colleges and universities. In the United States aparallel to the difficulties experienced by West Afri-can scientists exist at HBCUs. In this session, we com-pared and contrasted the similarities and differences,the various obstacles (lack of resources, mission state-ments, sense of isolation), and strategies for produc-ing successful research efforts. This session also pro-vided an opportunity for several scientists inatmospheric sciences programs at HBCUs to describethe research that was being undertaken in order toencourage collaboration with West African scientists.

The representatives from the HBCUs were Dr.Vernon Morris and Dr. Everette Joseph of HowardUniversity and Dr. Ali Omar of Hampton University.These schools have graduate programs in the atmo-spheric sciences. The faculty members at HowardUniversity described the various areas of active re-search—which include atmospheric chemistry, re-mote sensing, and radiative transfer—and the inten-tion of expanding into the area of regional climatemodeling. They also discussed the continuous pro-cess of making a transition at HBCUs from the origi-nal mission statement of teaching to one that allowsfor competitive research programs at Howard Uni-versity. At Hampton University the research pro-grams associated with aerosol measurements fromspaceborne platforms in addition to traditional mea-surements using lidar were described. New researchinitiatives in the coming years were described withthe hopes of increasing collaboration with West Af-rican scientists.

Understanding and overcoming barriers inhibiting col-laborations between West African and U.S. scientists.PROGRAMS WITHIN THE NSF. In this session, the pro-grams for international collaboration at NSF along withprograms that have been initiated elsewhere weredescribed. At NSF there is an international programthat provides support for American scientists that aretraveling to West Africa for research purposes.Currently, funds cannot be used to capacity build edu-cational institutes (human resources, infrastructure,and computer equipment) in West Africa.

PROGRAMS IN WEST AFRICA THAT FOSTER COLLABORATION.Two programs leading to opportunities for West Af-rican scientists while increasing collaboration be-tween West African and European scientists weredescribed by M. S. Boulahya, director of African Cen-tre of Meteorological Applications and Development(ACMAD) in Niamey, Niger. ACMAD has the long-term goal of increasing meteorological applicationsfor sustainable development while also assisting na-tional meteorological services to develop collabora-tion with its data users.

The Fonds d’Incitation à la Recherche Météor-ologique en Afrique (FIRMA)-ACMAD program isa central fund for meteorological research in Africa.This effort is funded by the French government (theFrench Cooperation). This is done by providing re-sources to different research teams for undertakingmultidisciplinary research such as weather prediction,seasonal forecast, and applications for agriculture andwater resource management, and health.

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The Prévisions Saisonnières pour l’Afrique del’Oest (PRESAO) program develops seasonal forecastwith applications for food security in West Africa. Ithas gone through various stages (implementation, de-velopment, and maturity) over a 6-yr period. Therehave been extensive training programs associated withPRESAO at the national meteorological centers.

Dr. Adedodyin from the University of Botswanasuggested that the “Edward Bouchet” conferences thathave taken place in Africa and the United States overthe last decade can serve as a mechanism for increas-ing expertise and promoting capacity building in Af-rica. This conference brings together Africans andAfrican Americans in the areas of physics for severaldays of presentation. Dr. Edward Bouchet, who wasthe first African American to receive a Ph.D. in phys-ics (1876 for Yale University) has served as a sourceof inspiration for scientists of African descent.Through creative measures associated with this con-ference it may be possible to provide West Africangraduate students with the opportunity to undertakeresearch at sister universities in the United States.

WORKING GROUP SESSIONS. There was a breakout sessionwith three working groups given the responsibility ofdiscussing the following areas:

• collaborative research and capacity building(working group 1),

• scholarship and dissemination of research activi-ties (working group 2), and

• academics and capacity building (working group 3).

Working group 1 was asked to consider the following:

1) how to ensure that collaborative research could beundertaken with the goals of equal partnership;

2) the challenges of communication including lan-guage, and modes of communication between col-laborators (Internet, fax, telephones);

3) the challenges of technology issues including thedifferences in technology and technology transfer;

4) assessing capacity building within the existingframework of universities and institutions in WestAfrica and identify the challenges, barriers, and op-portunities for capacity building; and

5) identifying potential sources of funding to facili-tate capacity building in West Africa.

The working group found that the most difficultissues were related to existing institutions and capacitybuilding within these institutions. They thought thatthere was a need to do a realistic assessment of the

existing institutions in West Africa that would serveas an ideal institute for scientific collaboration with aU.S. institution. After such an assessment is done,there might exist the possibility of working toward amemorandum of understanding (MOU) betweenthose institutions in West Africa and the UnitedStates. Other points included the following.

• Communication is one of the greatest barriers fac-ing scientific collaboration; therefore, an assess-ment of the capacity to communicate must be doneat an early stage.

• Any capacity building must leave the West Afri-can institutes with the ability to conduct their ownindependent research with the available equipmentafter some initial phase.

• Workshops should be conducted so that WestAfrican collaborators can remain up-to-date withrecent changes in scientific methodology andtechnology.

• West African institutions that are involved in col-laboration with U.S. institutes should work to de-velop user-end products. This could be in the ar-eas of seasonal variability, climate variability, orclimate change.

Working group 2 was asked to consider the follow-ing questions.

1) What specific factors are limiting the publishing ofscientific manuscripts by West African scientists(especially in U.S. journals)?

2) Are there simple solutions to fix the problem?3) What factors are limiting the presentation of re-

search at conference (especially in the UnitedStates) by West African scientists?

4) Are there simple solutions to fix the problem?5) Is there an awareness of these issues within the me-

teorological community?

A summary of the proposed solutions to these ques-tions can be found in Jenkins and Diongue (2000).Working group 3 was asked to consider the follow-ing questions.

1) What are the key elements that have limited thenumber of academic programs (meteorology) inWest Africa?

2) Are there pathways to either increase the numberof academic programs in West Africa orstrengthen existing programs?

3) Are there U.S. exchange programs in West Africathat relate to meteorology? Is the postdoc path the


only way to have collaboration with West Africanscientists?

4) What is necessary to start an exchange program?5) How can we ensure that faculty/instructors in West

Africa have up-to-date textbooks for instruction?6) Will it be possible to share courses over the

Internet in the near future? Is it possible now?Where?

This working group came to the following conclusions.

• The key element that limits meteorology depart-ments in West Africa is the lack of awareness andthe importance that these departments may playin understanding weather and climate related is-sues. There is also a lack of collaboration betweenother institutions in a particular country and WestAfrican atmospheric sciences/meteorology depart-ments. Finally, the lack of employment after ob-taining a graduate degree not only discouragesthose pursuing these degrees, but ultimately leadsto “brain drain” as these scientists find work out-side of the country.

• The primary educational institutions in West Af-rica where the study of atmospheric sciences/meteorology are being taught or undertaken isEAMAC in Niamey, Niger, for operational meteo-rologists, and LPA in Dakar, Senegal, where re-search is being undertaken for graduate degrees.However, at LPA there is not a formal graduatedegree program with university-approved coursesin place.

• There were no exchange programs between WestAfrican and U.S. institutes that were identified, butinformally there have been individual scientiststhat have tried to foster collaboration (P. Lamb,University of Oklahoma; S. Nicholson, FloridaState University).

• Because faculty positions in West Africa are diffi-cult to obtain, we must look to strengthen the tiesbetween West African and U.S. educational insti-tutes. Faculty and student exchange programs arethe easiest paths to strengthening West African–U.S. relationships. Moreover, U.S. scholars shouldtry to spend time in West Africa teaching and help-ing to develop meteorology courses in addition toundertaking collaborative research.

• If an atmospheric science department does not ex-ists, then in order to start such a department orprogram, it will be necessary to develop supportfrom within the country, stressing the importanceof such a program to the social, economic, and edu-cational welfare of that country. Such a program

will need support from outside institutions in pro-moting this perspective by helping to demonstratehow the department’s contributions are linked toother international programs or research efforts.

• In order to ensure that faculty/instructors have up-to-date textbooks efforts should be made to donatetextbooks and journal, and to seek funding fromprofessional organizations or private foundationsfor text books. Universities should also work withexisting organizations such as ACMAD with thepurpose of securing funding for textbooks.

• It is currently possible to share courses over theInternet if West African educational institutes haveInternet capability. This capacity should only in-crease in the future. It is also possible to use insti-tutions such as ACMAD as a resource to deliverthese courses to target institutions. For World WideWeb–based courses that currently exist, West Afri-can institutes will need to contact the developers.

New research opportunities for the West African climatesystem. The presentations from this session were di-rected toward interdisciplinary research associatedwith hydrology, biosphere–atmosphere interactions,a recent field experiment in West Africa, and exam-ining easterly wave activity.

HYDROLOGY AND BIOSPHERE–ATMOSPHERE INTERACTIONS.While there has been a downward trend for rain inWest Africa, extreme events associated with heavyprecipitation and above normal seasonal precipitationin West Africa occurred during 1998 and 1999. Thefloods of 1998 were associated with fatalities, loss ofproperty, and the displacement of many individualsin Nigeria and affected the neighboring countries ofNiger, Burkina Faso, and Senegal. Research efforts toforecast short-term-to-seasonal streamflow along theNiger River were presented. Streamflow forecasts areproduced from satellite-derived precipitation rates;soil and land-cover parameters are used as input intohydrology models.

While early scientific studies examined the role ofdeforestation and desertification (Charney 1975) inrelation to negative precipitation anomalies in WestAfrica, these studies did not incorporate realistic bio-sphere–atmosphere schemes, until the late 1980s andearly 1990s (Xue and Shukla 1993, 1996). Even thesesimulations did not consider the two-way interactionbetween atmosphere and the biosphere, but ratheronly the impact of the biosphere on the atmosphere.Studies presented in this session with one- and two-way atmosphere–biosphere interactions show that notonly can changes in vegetation cover produce decadal

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reductions in the precipitation, similar to those ob-served (Wang and Elthair 2000), but they also par-tially explain the increase in surface temperatures thathas been observed. Moreover, simulations withouttwo-way feedback cannot determine how the naturalland-cover is affected by anthropogenic land-use changein West Africa. A sample of presentations from this ses-sion includes the following: Short-Term-to-SeasonalForecast of Flood Risk in the Lower Niger River Ba-sin (challenges and prospects; Dr. James Adegoke),Modeling the Regional Climate over West Africa (theimportance of biospheric feedback; Dr. GuilingWang), and Examining The Effects of Land-SurfaceProcesses in the Center for Ocean–Land–Atmosphere(COLA) and NCEP GCMs (Dr. Yongkang Xue).

EXAMINATION OF EASTERLY WAVES THROUGH WAVELET ANALY-SIS AND THE JET2000 EXPERIMENT. Easterly waves are im-portant synoptic features in West Africa because ofthe production of rain. Moreover these easterly wavescan lead to the generation of tropical disturbances inthe tropical Atlantic basin. Therefore, it is necessaryto have a thorough understanding of the genesis andevolution of these waves as they propagate across WestAfrica. Atmospheric motions on different timescalesand easterly wave activity can be examined throughwavelet analysis. This technique can be used to exam-ine the seasonal activity of easterly waves by analyz-ing lower-troposphere (700, 850 hPa) meridionalwinds, geopotential height or vorticity. Dr. AndreKanga provided the theoretical background and ap-plication of wavelet analysis. A short but potentially use-ful field experiment entitled (JET2000) was undertakenin West Africa during the period of 25–29 August 2000to examine the middle to lower troposphere with air-craft and surface meteorological measurements. Theinteraction of the AEJ with westward-propagatingeasterly waves and a host of other measurements werestudied in this field experiment with a summary of theresults expected in 2001 (www.env.leeds.ac.uk/JET2000). Dr. Miriam Diop described the goals andobjectives of the JET2000 experiment.

Closing discussion. A number of topics were discussedin this last but informal session. They included thefollowing.

FUNDING CHALLENGES. There is a need to identifypotential funding sources (federal, international, andnonprofit foundations) for capacity building of WestAfrican institutes. LPA is one such institute thatdeserves a high priority, since it is one of the fewinstitutes in West Africa where research is undertaken

and doctorate degrees are generated. However, it doesnot have a strong teaching component, but hopefullya partnership with a U.S. university (such as HowardUniversity) could alleviate this problem through theuse of visiting scholars in the development and teach-ing of courses in atmospheric sciences.

NSF does not currently have specific programs tohelp in the capacity building process; however, it doesnot have to remain this way. NSF could generate newinitiatives that stimulate collaboration between U.S.and West African scientists and thereby promote ca-pacity building over short to midterm periods withspecific research goals in mind. Moreover, NSF pro-grams that promote faculty and student exchangeprograms can provide rich and meaningful experi-ences for all participants. African American facultyand students who have strong historical ties to WestAfrica could benefit significantly from such a pro-gram. NSF programs that promote technology trans-fer would accelerate capacity building efforts in WestAfrica.

While the discussion related to research activitiesremains unresolved, in the short term, researchersshould make an effort to apply their work towardan end user. This will allow national governmentsto see the practical usefulness of a particular typeof research. Moreover researchers that are examiningclimate variability should try to relate their researchto the Climate Variability and Predictability(CLIVAR) program in Africa. This may allowgovernment or funding agencies to see a particularresearch program in the context of internationalefforts.

EDUCATION CHALLENGES. There are several universities(LPA in Senegal, EAMAC in Niger, Minna Univer-sity of Technology in Nigeria) that offer undergradu-ate or graduate studies in the atmospheric sciences(through traditional meteorology programs or geog-raphy programs) that should be considered as possiblemembers/affiliates, through some creative measures,to the University Cooperation for Atmospheric Re-search (UCAR). This would allow West African at-mospheric science programs to have a better under-standing of the current status of meteorologyprograms in the United States. UCAR might also fa-cilitate in developing exchange programs (curriculumdetails) and provide assistance for future workshopsin the United States or West Africa. Finally, effortsshould be made to assess the current status of all WestAfrican departments or programs in related atmo-spheric science areas as a first step toward buildingWest African–U.S. education partnerships.


AN ORGANIZATION TO FOSTER U.S.–WEST AFRICAN SCI-ENTISTS RESEARCH INTERESTS. Because of the interactionthat scientists enjoyed over the 3-day period we feltthat it was necessary to form an organization that willallow for continued interaction. This transatlanticorganization would include scientists from theUnited States and West Africa (including thoseworking or studying in Europe) in the atmosphericsciences. Through the use of the Internet, it wouldbe possible to post recent news (new Ph.D. gradu-ates, upcoming field experiments, graduate orpostgraduate opportunities), create a database of rel-evant publications, and announce upcoming work-shops or conferences. This organization could alsoserve as a mechanism of carrying various issues in acohesive manner to the larger community. Workinggroups (GCM, regional modeling, applications ofdata) could use this Web site for planning experi-ments, posting results, and exchanging in-progressmanuscripts.

A proposed plan for capacity building. A serious attemptto identify West African institutions and potentialpartnerships between West African–U.S. institutions(educational, research) should be pursued. Becauseof the important environmental factors that exist inWest Africa (land-use change, climate variability,climate change, atmospheric chemistry), an educa-tional institute that has demonstrated the capacity orhas the potential to create a department/program thatis research oriented should be sought. It is importantthat this center serve as a facility where atmosphericresearch is conducted. But an equally importantmission of this institute is the need for it to serve asthe learning center where West African faculty mem-bers guide future generations of West African stu-dents in the atmospheric sciences. Faculty and stu-dents from such an institute will add to the body ofknowledge in the evolution of atmospheric scienceson a global basis. The operational meteorologicalcenter cannot be left out of this process, but mustwork closely with this educational center since manyof its students may ultimately have careers in theoperational meteorological services. While it is notabsolutely necessary that the potential institute be-comes an atmospheric science department or pro-gram, this institute should be linked to the educa-tional processes. Such a institution should also belinked to existing institutions in West Africa (e.g.,ACMAD) and ultimately institutions in other regionsof Africa.

Why is such a center important to the globalcommunity?

• It serves as a site where long-term collaborationcould take place.

• In the case of field experiments in West Africa orcentral Africa, it can serve as a command and con-trol center. Moreover, faculty, students, and re-searchers who are associated with these institutescan take part in any measurements and in theiranalysis, and submit scientific publications. Thiscenter can reduce the uncertainty in the logisticsof planning field experiments in West Africa sincethe facilities and personnel would be a fixedparameter.

• Over the past few years and during this decade, anumber of satellites will be launched primarily bythe National Aeronautics Space Administration(NASA) and the European Space Agency (ESA)that will monitor and measure processes that drivethe climate system (precipitation, aerosols, radia-tion), affect the global chemistry (trace gases suchas O3, CO, NO, aerosols, lightning), and identifychanges in the land surface. For any such invest-ment, there must be some way of comparing re-motely sensed values to measured values at theground. This aspect has been largely ignored withrespect to Africa—a continent where remotelysensed observations are valued, especially insparsely observed or economically depressed areas.This institute could serve as a site where groundvalidation and data processing could take place.

While the concept of a research–education centerin West Africa might be a good idea, the question offunding such a center, and the proper managementto ensure that it can survive over long periods of time,is challenging. Funding for such a center will need tocome from both within and outside of the institution’scountry. Funding and expert advice from govern-ment, industrial, and nonprofit organizations are nec-essary to build such a center. The short-term andlong-term benefits of such a center must be properlydemonstrated to potential contributors. The benefitsinclude education, employment, contributions of re-search from the West African scientific community,a research base for field experiments, and technologytransfer that will increase future collaboration.

The facilities for such a center could be built fromthe ground or developed from existing facilities. Thefacilities will need to consider some of the obstaclesthat were discussed in this workshop. Communicationis a critical need, with phone, fax, and Internet capa-bility being required. Such a center should have class-room facilities and conference capabilities, with lan-guage translation equipment when international

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workshops or conferences are held. Computer facili-ties for research (for example, clusters of PCs withLINUX-based systems for short-term forecasts, andGCM and regional climate model studies) and labo-ratory facilities are required. Finally, such a centershould be developed with the understanding ofchanging technology and therefore built with the ca-pacity to change and upgrade without much difficultyand with minimal costs.

Such an institution should not develop in iso-lation, but should be linked to other institutes in theUnited States (for example NCAR, universities, andthe American Meteorological Society) and Europe.This institution should have an advisory board fromexternal institutions that have minimal political oreconomic stakes to help steer it in the initial stages.If this institution is an atmospheric science depart-ment or program, it could help itself by finding asister institution (e.g., Howard University or Hamp-ton University) or a set of sister institutions. Thesister institution(s) could help to develop the cur-riculum, participate in sponsoring workshops,promote student and faculty exchange programs,undertake collaborative research, and seed fundingfor joint institutional research efforts. The ultimategoal of this center would be to become self-sustainingthrough research projects with international col-laboration and support from institutions in WestAfrica (government and private sectors) while alsoproviding graduate school opportunities for futuregenerations of West Africa citizens in the atmo-spheric sciences.

ACKNOWLEDGMENTS. This research was supportedby the International Division at the National Science Foun-dation under Grant INT-9987639.

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The Father James B. Macelwane Annual Award

The Father James B. Macelwane Annual Award was established by the American Meteorological Societyto honor the late Rev. James B. Macelwane, S.J., a world-renowned authority of seismology, who was ageophysicist and Dean of the Institute of Technology, Saint Louis University, until his death in 1956. The recipientof the Father James B. Macelwane award will receive a stipend of $300.

The purpose of this award is to stimulate interest in meteorology among college students through theencouragement of original student papers concerned with some phase of the atmospheric sciences. The studentmust be enrolled as an undergraduate at the time the paper is written, and no more than two students from anyone institution may enter papers in any one contest.

Submission of Papers:To consider papers for the Macelwane Award, the AMS Committee of Judges must receive the following:1) an original plus four copies of the paper; 2) a letter of application from the author, including contactinformation, stating the title of the paper and the name of the university at which the paper was written; 3) aletter from the department head or other faculty member of the major department, confirming that the authorwas an undergraduate student at the time the paper was written, and indicating the elements of the paper thatrepresent original contributions by the student.

The above information must be received at the American Meteorological Society, Attn: Donna Fernandez,45 Beacon Street, Boston, MA 02108-3693 by 14 June 2002. The evaluation of the papers occurs during thesummer. Announcement of the award recipient is made in October of 2002.

AMS UNDERGRADUATE AWARD

investigating the west african climate system using global/regional climate models

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