Moisture Variability and Multiscale Interactions during Spring in West Africa

Monthly Weather Review

Volumn 142, Issue 9, 2014, Pages 3178-3198

  Mera, Roberto ^a   Laing, Arlene G ^b   Semazzi, Frederick ^c  

^a UNION OF CONCERNED SCIENTISTS   (United States)

^b NATIONAL CENTER FOR ATMOSPHERIC RESEARCH   (United States)

^c NORTH CAROLINA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

COASTAL ZONES; RAIN;

BACTERIAL MENINGITIS; CIRCULATION PATTERNS; EQUATORIAL ROSSBY WAVES; EXTRATROPICAL CYCLONES; HIGH RELATIVE HUMIDITIES; MULTISCALE INTERACTIONS; OUTGOING LONGWAVE RADIATION; TEMPORAL VARIABILITY;

MOISTURE;

BACTERIA (MICROORGANISMS);

EID: 84906877454     PISSN: 00270644     EISSN: 15200493     Source Type: Journal    
DOI: 10.1175/MWR-D-13-00175.1     Document Type: Article

References (65)

1. Ati, O. F., C. J. Stigter, and E. O. Oladipo, 2002: A comparison of methods to determine the onset of the growing season in northern Nigeria. Int. J. Climatol., 22, 731-742, doi:10.1002/ joc.712.
2. Berry, G. J., and C. D. Thorncroft, 2012: African easterly wave dynamics in a mesoscale numerical model: The upscale role of convection. J. Atmos. Sci., 69, 1267-1283, doi:10.1175/ JAS-D-11-099.1.
3. Besancenot, J. P., M. Boko, and P. C. Oke, 1997: Weather condi- tions and cerebrospinal meningitis in Benin (Gulf of Guinea, West Africa). Eur. J. Epidemiol., 13, 807-815, doi:10.1023/ A:1007365919013.
4. Bessafi, M., and M. C. Wheeler, 2006: Modulation of south Indian Ocean tropical cyclones by the Madden-Julian oscillation and convectively coupled equatorial waves. Mon. Wea. Rev., 134, 638-656, doi:10.1175/MWR3087.1.
5. Cuesta, J., C. Lavaysse, C. Flamant, M. Mimouni, and P. Knippertz, 2010: Northward bursts of the West African monsoon leading to rainfall over the Hoggar Massif, Algeria. Quart. J. Roy. Meteor. Soc., 136, 174-189, doi:10.1002/qj.439.
6. Diedhiou, A., S. Janicot, A. Viltard, P. de F'elice, and H. Laurent, 1999: Easterly wave regimes and associated convection over West Africa and the tropical Atlantic: Results from the NCEP/NCAR and ECMWF reanalyses. Climate Dyn., 15, 795-822, doi:10.1007/s003820050316.
7. Dukic, V., and Coauthors, 2012: The role of weather in meningitis outbreaks in Navrango, Ghana: A generalized additive mod- eling approach. J. Agric. Biol. Environ. Stat., 17, 442-460, doi:10.1007/s13253-012-0095-9.
8. Eltahir, E. A. B., and C. Gong, 1996: Dynamics of wet and dry years in the West Africa. J. Climate, 9, 1030-1042, doi:10.1175/ 1520-0442(1996)009,1030:DOWADY.2.0.CO;2.
9. Flamant, C., J. P. Chaboureau, D. P. Parker, C. M. Taylor, J. P. Cammas, O. Bock, F. Timouk, and J. Pelon, 2007: Airborne observations of the impact of a convective system on the planetary boundary layer thermodynamics and aerosol dis- tribution in the intertropical discontinuity region of the West African monsoon. Quart. J. Roy. Meteor. Soc., 133, 1175-1189, doi:10.1002/qj.97.
10. Flamant, C., P. Knippertz, D. J. Parker, J.-P. Chaboureau, C. Lavaysse, A. Agusti-Panareda, and L. Kergoat, 2009: The impact of a mesoscale convective system cold pool on the northward propagation of the intertropical discontinuity over West Africa. Quart. J. Roy. Meteor. Soc., 135, 139-159, doi:10.1002/qj.357.
11. Flohn, H., 1975: Tropische Zirkulationsformen im Lichte der Satellitenaufnahmen (Tropical Circulation Types as Reflected in Satellite Imagery). Bonner Meteorologische Abhandlungen, No. 21, Westdeutscher Verlag, 82 pp.
12. Frank, W. M., and P. E. Roundy, 2006: The role of tropical waves in tropical cyclogenesis. Mon. Wea. Rev., 134, 2397-2417, doi:10.1175/MWR3204.1.
13. Greenwood, B., 1999: Meningococcal meningitis in Africa. Trans. Roy. Soc. Trop. Med. Hyg., 93, 341-353, doi:10.1016/ S0035-9203(99)90106-2.
14. Grist, J., 2002: Easterly waves over Africa. Part I: The seasonal cycle and contrasts between wet and dry years. Mon. Wea. Rev., 130, 197-211, doi:10.1175/1520-0493(2002)130,0197: EWOAPI.2.0.CO;2.
15. Gruber, A., and A. F. Krueger, 1984: The status of the NOAA outgoing longwave radiation data set. Bull. Amer. Meteor. Soc., 65, 958-962, doi:10.1175/1520-0477(1984)065,0958: TSOTNO.2.0.CO;2.
16. Gu, G., 2009: Intraseasonal variability in the equatorial Atlantic- West Africa during March-June. Climate Dyn., 32, 457-471, doi:10.1007/s00382-008-0428-0.
17. Gu, G., and R. F. Adler, 2004: Seasonal evolution and variabil- ity associated with the West African monsoon system. J. Climate, 17, 3364-3377, doi:10.1175/1520-0442(2004)017,3364: SEAVAW.2.0.CO;2.
18. Hagos, S. M., and K. H. Cook, 2007: Dynamics of the West African monsoon jump. J. Climate, 20, 5264-5284, doi:10.1175/ 2007JCLI1533.1.
19. Hagos, S. M., and K. H. Cook, 2009: Development of a coupled regional model and its application to the study of interactions be- tween the West African monsoon and the eastern tropi- cal Atlantic Ocean. J. Climate, 22, 2591-2604, doi:10.1175/ 2008JCLI2466.1.
20. Hoskins, B. J., and G.-Y. Yang, 2000: The equatorial response to higher-latitude forcing. J. Atmos. Sci., 57, 1197-1213, doi:10.1175/ 1520-0469(2000)057,1197:TERTHL.2.0.CO;2.
21. Janicot, S., F. Mounier, N. M. J. Hall, S. Leroux, B. Sultan, and G. N. Kiladis, 2009: Dynamics of the West African monsoon. Part IV: Analysis of 25-90-day variability of convection and the role of the Indian monsoon. J. Climate, 22, 1541-1565, doi:10.1175/2008JCLI2314.1.
22. Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Re- analysis Project. Bull. Amer. Meteor. Soc., 77, 437-471, doi:10.1175/1520-0477(1996)077,0437:TNYRP.2.0.CO;2.
23. Kiladis, G. N., 1998: Observations of Rossby waves linked to convection over the eastern tropical Pacific. J. Atmos. Sci., 55, 321-339, doi:10.1175/1520-0469(1998)055,0321: OORWLT.2.0.CO;2.
24. Kiladis, G. N., and M. Wheeler, 1995: Horizontal and vertical structure of observed tropospheric equatorial Rossby waves. J. Geophys. Res., 100, 22 981-22 997, doi:10.1029/95JD02415.
25. Kiladis, G. N., C. D. Thorncroft, and N. M. J. Hall, 2006: Three-dimensional structure and dynamics of African easterly waves. Part I: Ob- servations. J. Atmos. Sci., 63, 2212-2230, doi:10.1175/JAS3741.1.
26. Kiladis, G. N., M. C. Wheeler, P. T. Haertel, and P. E. Roundy, 2009: Convectively coupled equatorial waves. Rev. Geophys., 47, RG2003, doi:10.1029/2008RG000266.
27. Knippertz, P., and A. H. Fink, 2008: Dry-season precipitation in tropical West Africa and its relation to forcing from the ex- tratropics. Mon. Wea. Rev., 136, 3579-3596, doi:10.1175/ 2008MWR2295.1.
28. Knippertz, P., and A. H. Fink, 2009: Prediction of dry-season precipitation in tropical West Africa and its relation to forcing from the ex- tratropics. Wea. Forecasting, 24, 1064-1084, doi:10.1175/ 2009WAF2222221.1.
29. Laing, A. G., and J. M. Fritsch, 1993: Mesoscale convective com- plexes in Africa. Mon. Wea. Rev., 121, 2254-2263, doi:10.1175/ 1520-0493(1993)121,2254:MCCIA.2.0.CO;2.
30. Laing, A. G., R. E. Carbone, V. Levizzani, and J. D. Tuttle, 2008: The propagation and diurnal cycles of deep convection in northern tropical Africa. Quart. J. Roy. Meteor. Soc., 134, 93-109, doi:10.1002/qj.194.
31. Le Barbé, L., T. Lebel, and D. Tapsoba, 2002: Rainfall variability in West Africa during the years 1950-90. J. Climate, 15, 187-202, doi:10.1175/1520-0442(2002)015,0187:RVIWAD.2.0.CO;2.
32. Lélé, M. I., and P. J. Lamb, 2010: Variability of the intertropical front (ITF) and rainfall over the West African Sudan-Sahel zone. J. Climate, 23, 3984-4004, doi:10.1175/2010JCLI3277.1.
33. Lin, Y.-L., K. E. Robertson, and C. M. Hill, 2005: Origin and propagation of a disturbance associated with an African easterly wave as a precursor of Hurricane Alberto (2000). Mon. Wea. Rev., 133, 3276-3298, doi:10.1175/MWR3035.1.
34. Madden, R. A., and P. R. Julian, 1994: Observations of the 40-50-day tropical oscillation-A review. Mon. Wea. Rev., 122, 814-837, doi:10.1175/1520-0493(1994)122,0814:OOTDTO.2.0.CO;2.
35. Matthews, M., 2004: Intraseasonal variability over tropical Africa during northern summer. J. Climate, 17, 2427-2440, doi:10.1175/ 1520-0442(2004)017,2427:IVOTAD.2.0.CO;2.
36. McGuirk, J. P., A. H. Thompson, and J. R. Schaefer, 1988: An eastern Pacific tropical plume. Mon. Wea. Rev., 116, 2505-2521, doi:10.1175/1520-0493(1988)116,2505:AEPTP.2.0.CO;2.
37. Mekonnen, A., C. D. Thorncroft, A. R. Aiyyer, and G. N. Kiladis, 2008: Convectively coupled Kelvin waves over tropical Africa during the boreal summer: Structure and variability. J. Climate, 21, 6649-6667, doi:10.1175/2008JCLI2008.1.
38. Mera, R., A. Laing, and F. H. M. Semazzi, 2010: Variability of atmospheric moisture during the boreal spring in West Africa. 29th Conf. on Hurricanes and Tropical Meteorology, Tucson, AZ, Amer. Meteor. Soc., 6D.4. [Available online at https:// ams.confex.com/ams/pdfpapers/168968.pdf.]
39. Molesworth, A. M., L. E. Cuevas, A. P. Morse, J. R. Herman, and M. C. Thomson, 2002: Dust clouds and spread of infection. Lancet, 359, 81-82, doi:10.1016/S0140-6736(02)07304-X.
40. Molesworth, A. M., L. E. Cuevas, S. J. Connor, A. P. Morse, and M. C. Thomson, 2003: Environmental risk and meningitis epidemics in Africa. Emerging Infect. Dis., 9, 1287-1293, doi:10.3201/ eid0910.030182.
41. Molinari, J., K. Lombardo, and D. Vollaro, 2007: Tropical cyclo- genesis within an equatorial Rossby wave packet. J. Atmos. Sci., 64, 1301-1317, doi:10.1175/JAS3902.1.
42. Mounier, F., G. N. Kiladis, and S. Janicot, 2007: Analysis of the dominant mode of convectively coupled Kelvin waves in the West African monsoon. J. Climate, 20, 1487-1503, doi:10.1175/ JCLI4059.1.
43. Nguyen, H., and J.-P. Duvel, 2008: Synoptic wave perturbations and convective systems over equatorial Africa. J. Climate, 21, 6372-6388, doi:10.1175/2008JCLI2409.1.
44. Nicholson, S. E., 1981: Rainfall and atmospheric circulation during drought periods and wetter years in West Africa. Mon. Wea. Rev., 109, 2191-2208, doi:10.1175/1520-0493(1981)109,2191: RAACDD.2.0.CO;2.
45. Okumura, Y., and S. Xie, 2004: Interaction of the Atlantic equa- torial cold tongue and the African monsoon. J. Climate, 17, 3589-3601, doi:10.1175/1520-0442(2004)017,3589: IOTAEC.2.0.CO;2.
46. Omotosho, B., A. A. Balogun, and K. Ogunjobi, 2000: Predicting monthly and seasonal rainfall, onset, and cessation of the rainy season in West Africa using only surface data. Int. J. Climatol., 20, 865-880, doi:10.1002/1097-0088(20000630)20:8,865: :AID-JOC505.3.0.CO;2-R.
47. Pohl, B., Y. Richard, and N. Fauchereau, 2007: Influence of the Madden-Julian oscillation on southern African summer rainfall. J. Climate, 20, 4227-4242, doi:10.1175/JCLI4231.1.
48. Pospichal, B., D. B. Karam, S. Crewell, C. Flamant, A. Hünerbein, O. Bock, and F. Said, 2010: Diurnal cycle of the intertropical discontinuity over West Africa analysed by remote sensing and mesoscale modeling. Quart. J. Roy. Meteor. Soc., 136, 92- 106, doi:10.1002/qj.435.
49. Ramel, R., H. Gallée, and C. Messager, 2006: On the northward shift of the West African monsoon. Climate Dyn., 26, 429-440, doi:10.1007/s00382-005-0093-5.
50. Reed, R. J., D. C. Norquist, and E. E. Recker, 1977: The structure and properties of African wave disturbances as observed during phase III of GATE. Mon. Wea. Rev., 105, 317-333, doi:10.1175/1520-0493(1977)105,0317:TSAPOA.2.0.CO;2.
51. Roundy, P. E., and W. M. Frank, 2004: A climatology of waves in equatorial region. J. Atmos. Sci., 61, 2105-2132, doi:10.1175/ 1520-0469(2004)061,2105:ACOWIT.2.0.CO;2.
52. Sijikumar, S., P. Roucou, and B. Fontaine, 2006: Monsoon onset over Sudan-Sahel: Simulation by the regional scale model MM5. Geophys. Res. Lett., 33, L03814, doi:10.1029/2005GL024819.
53. Straub, K. H., and G. N. Kiladis, 2002: Observations of a convectively coupled Kelvin wave in the eastern Pacific ITCZ. J. At- mos. Sci., 59, 30-53, doi:10.1175/1520-0469(2002)059,0030: OOACCK.2.0.CO;2.
54. Straub, K. H., and G. N. Kiladis, 2003a: Extratropical forcing of convectively coupled Kelvin waves during austral summer. J. Atmos. Sci., 60, 526-543, doi:10.1175/1520-0469(2003)060,0526: EFOCCK.2.0.CO;2.
55. Straub, K. H., and G. N. Kiladis, 2003b: Interaction between the boreal summer intraseasonal oscillation and higher-frequency tropical wave activity. Mon. Wea. Rev., 131, 945-960, doi:10.1175/ 1520-0493(2003)131,0945:IBTBSI.2.0.CO;2.
56. Sultan, B., and S. Janicot, 2000: Abrupt shift of the ITCZ over West Africa and intra-seasonal variability. Geophys. Res. Lett., 27, 3353-3356, doi:10.1029/1999GL011285.
57. Sultan, B., and S. Janicot, 2003: The West African monsoon dynamics. Part II: The preonset and onset of the summer monsoon. J. Cli- mate, 16, 3407-3427, doi:10.1175/1520-0442(2003)016,3407: TWAMDP.2.0.CO;2.
58. Sultan, B., K. Labadi, J. F. Guegan, and S. Janicot, 2005: Climate drives the meningitis epidemics onset in West Africa. PLoS Med., 2, e6, doi:10.1371/journal.pmed.0020006.
59. Tetzlaff, G., and M. Peters, 1988: A composite study of early summer squall lines and their environment over West Africa. Meteor. Atmos. Phys., 38, 153-163, doi:10.1007/ BF01029779.
60. Thomson, M. C., A. M. Molesworth, M. H. Djingarey, K. R. Yameogo, F. Belanger, and L. E. Cuevas, 2006: Potential of environmental models to predict meningitis epidemics in Africa. Trop. Med. Int. Health, 11, 781-788, doi:10.1111/ j.1365-3156.2006.01630.x.
61. Thorncroft, C. D., and H. A. Flocas, 1997: A case study of Saharan cyclogenesis. Mon. Wea. Rev., 125, 1147-1165, doi:10.1175/ 1520-0493(1997)125,1147:ACSOSC.2.0.CO;2.
62. Wheeler, M., and G. N. Kiladis, 1999: Convectively coupled equatorial waves: Analysis of clouds and temperature in the wavenumber-frequency domain. J. Atmos. Sci., 56, 374-399, doi:10.1175/1520-0469(1999)056,0374:CCEWAO.2.0.CO;2.
63. Xie, P., and P. A. Arkin, 1997: Global precipitation: A 17-year monthly analysis based on gauge observations, satellite esti- mates, and numerical model outputs. Bull. Amer. Meteor. Soc., 78, 2539-2558, doi:10.1175/1520-0477(1997)078,2539: GPAYMA.2.0.CO;2.
64. Yaka, P., B. Sultan, H. Broutin, S. Janicot, S. Philippon, and N. Fourquet, 2008: Relationships between climate and year- to-year variability in meningitis outbreaks: A case study in Burkina Faso and Niger. Int. J. Health Geogr., 7, 34, doi:10.1186/ 1476-072X-7-34.
65. Yang, G.-Y., B. Hoskins, and J. Slingo, 2007: Convectively coupled equatorial waves. Part III: Synthesis structures and their forcing and evolution. J. Atmos. Sci., 64, 3438-3451, doi:10.1175/ JAS4019.1.