Convective Rainfall in Amazonia and Adjacent Tropics


Hourly rainfall estimates from integrated satellite data are used to build a dynamically based climatology of convectively generated rainfall across South America, including tropical, sub-tropical and oceanic regions. Herein, we focus on 0S to 15S, including greater Amazon and NE Brazil leeward of the South Atlantic Ocean. Emphasis is placed on rainfall resulting from organized convective regimes, which are known to produce the majority of seasonal rainfall in various parts of South America and other continents. The statistical characteristics of individual events are quantified and examined with respect to regional atmospheric conditions. Among the factors considered are steering winds and wind shear, convective available potential energy (CAPE), sea and land breezes, and the occurrence of transient disturbances such as Kelvin Waves and Easterly Waves. Forcing and convective triggering mechanisms are inferred from the diagnosis of systematic patterns as evidenced in the continental diurnal cycle and longer periods of natural variability. The episodes of organized convection are analyzed in terms of their duration, span, phase speed, starting and ending time, starting and ending longitude, month and year through frequency distribution analysis. Most episodes of organized convection tend to move westward across the Amazon Basin. Descriptive statistics indicate average phase speed of westward and eastward episodes of convection in the Amazon basin at -11.8 m.s-1 and 13.0 m.s-1, respectively. Eastward propagating systems are influenced by northeastward moving cold fronts in Southern South America and tend to trigger and to organize convection across the Amazon Basin. Hourly rainfall analyses indicate that convection over the Amazon region is often organized.

Share and Cite:

Filho, A. , Carbone, R. , Tuttle, J. and Karam, H. (2015) Convective Rainfall in Amazonia and Adjacent Tropics. Atmospheric and Climate Sciences, 5, 137-161. doi: 10.4236/acs.2015.52011.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Joyce, R.J., Janowiak, J.E., Arkin, P.A. and Xie, P. (2004) CMORPH: A Method that Produces Global Precipitation Estimates from Passive Microwave and Infrared Data at High Spatial and Temporal Resolution. Journal of Hydrometeorology, 5, 487-503.<0487:CAMTPG>2.0.CO;2
[2] Negri, A.J., Agnostou, E.N. and Adler, R.F. (2000) A 10-Yr Climatology of Amazonian Rainfall Derived from Passive Microwave Satellite Observations. Journal of Applied Meteorology, 39, 42-56.<0042:AYCOAR>2.0.CO;2
[3] Negri, A.J., Adler, R.F. and Xu, L. (2002) A TRMM-Calibrated Infrared Rainfall Algorithm Applied over Brazil. Journal of Geophysical Research, 107, 8084, 16-1, 15, LBA Special Issue.
[4] Garreaud, R.D. and Wallace, J.M. (1997) The Diurnal March of Convective Cloudiness over the Americas. Monthly Weather Review, 125, 3157-3171.<3157:TDMOCC>2.0.CO;2
[5] Machado, L.A.T., Laurent, H., Dessay, N. and Miranda, I. (2004) Seasonal and Diurnal Variability of Convection over the Amazonia: A Comparison of Different Vegetation Types and Large Scale Forcing. Theoretical and Applied Climatology, 78, 61-77.
[6] Rickenbach, T.M., Nieto Ferreira, R., Halverson, J., Herdies, D.L. and Silva Dias, M.A.F. (2002) Modulation of Convection in the Southwestern Amazon Basin by Extratropical Stationary Fronts. Journal of Geophysical Research, 107, 8040.
[7] Pereira Filho, A.J., Silva Dias, M.A.F., Albrecht, R.I., Pereira, L.G.P., Tokay, A. and Rutledge, S. (2002) Multisensor Analysis of a Squall Line in the Amazon Region. Journal of Geophysical Research, 107, 8084, 21-1, 12, LBA Special Issue.
[8] Janowiak, J.E., Kousky, V.E. and Joyce, R.J. (2005) Diurnal Cycle of Precipitation Determined from the CMORPH High Spatial and Temporal Resolution Global Precipitation Analyses. Journal of Geophysical Research, 110, D23105.
[9] Kousky, V.E., Janowiak, J.E. and Joyce, R.J. (2006) The Diurnal Cycle of Precipitation over South America Based on CMORPH. Proceedings of 8 ICSHMO, INPE, Foz do Iguacu, 1113-1116.
[10] Huffman, G.J., Adler, R.F., Bolvin, D.T., Gu, G., Nelkin, E.J., Bowman, K.P., Hong, Y., Stocker, E.F. and Wolff, D.B. (2007) The TRMM Multi-Satellite Precipitation Analysis: Quasi-Global, Multi-Year, Combined-Sensor Precipitation Estimates at Fine Scale. Journal of Hydrometeorology, 8, 38-55.
[11] Hsu, K.L., Gao, X., Sorooshian, S. and Gupta, H.V. (1997) Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks. Journal of Applied Meteorology, 36, 1176-1190.<1176:PEFRSI>2.0.CO;2
[12] Carbone, R.E., Tuttle, J.D., Ahijevych, D.A. and Trier, S.B. (2002) Inferences of Predictability Associated with Warm Season Precipitation Episodes. Journal of the Atmospheric Sciences, 59, 2033-2056.<2033:IOPAWW>2.0.CO;2
[13] Pereira Filho, A.J., Carbone, R.E. and Tuttle, J.D. (2014) Convective Rainfall Systems in the La Plata Basin. Atmospheric and Climate Sciences, 4, 757-778.
[14] Laing, A.G., Carbone, R., Levizzani, V. and Tuttle, J. (2008) The Propagation and Diurnal Cycles of Deep Convection in Northern Tropical Africa. Quarterly Journal of the Royal Meteorological Society, 134, 93-109.
[15] Peixoto, J.P. and Oort, A.H. (1992) Physics of Climate. American Institute of Physics, College Park, 520 p.
[16] Pereira Filho, A.J., Carbone, R.E., Janowiak, J.E., Arkin, P., Joyce, R., Hallak, R. and Ramos, C.G.M. (2010) Satellite Rainfall Estimates over South America—Possible Applicability to the Water Management of Large Watersheds. Journal of the American Water Resources Association, 46, 344-360.
[17] Liu, C. and Zipser, E.J. (2008) Diurnal Cycles of Precipitation, Clouds, and Lightning in the Tropics from 9 Years of Trmm Observations. Geophysical Research Letters, 35, L04819.
[18] Wang, B. (2002) Kelvin Waves. Shankar, M., Ed., Elsevier Science Ltd., 7p.
[19] Kiladis, G.N., Wheeler, M.C., Haertel, P.T., Straub, K.H. and Roundy, P.E. (2009) Convectively Coupled Equatorial Waves. Reviews of Geophysics, 47, RG2003/2009 1-42.
[20] Keenan, T.D. and Carbone, R.E. (2008) Propagation and Diurnal Evolution of Warm Season Cloudiness in the Australian and Maritime Continental Region. Monthly Weather Review, 136, 973-994.
[21] Laing, A.G., Carbone, R. and Levizzani, V. (2011) Cycles and Propagation of Deep Convection over Equatorial Africa. Monthly Weather Review, 139, 2832-2853.
[22] Pereira Filho, A.J., Prado, L.F. and Santos, C.C. (2012) Precipitation Global, Regional and Local. In: Ciclo Ambiental da água da Chuva à Gestao, Blucher Publisher, 93-116. (In Portuguese)

Copyright © 2022 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.