A Study on Rain Rate Prediction of Southwestern Nigeria

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Folasade Abiola Semire
Adeyanju Adekunle
Robert Olayimika Abolade


Rainfall parameters can be utilized to investigate the effect of climate change through scientific methods. However, data on rainfall rate exceeded for a fraction of an average year is grossly unavailable over Nigeria’s climate, thereby diminishing the capability of existing models to adequately estimate the effect of degradation due to rain. Hence, more accurate estimation is required for better predictions. Rainfall volume data for six different locations in the south-western region of Nigeria were obtained for rain rate computation using Semire and Rosmiwati model. The curve-fitted Cumulative Distribution Functions were compared with the ITU-R rain rate model (Recommendation P.837-6) and compensation function was obtained using error analysis while the performance was evaluated with respect to existing models using Chi-square, and Percentage Error and Root Mean Square Error (RMSE) metrics. The outcome of this study can be adopted for better understanding of spatial rainfall intensity in this region and other climatic zones of similar rainfall characteristics.

Rain rate, cumulative distribution function, Southwestern Nigeria.

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How to Cite
Abiola Semire, F., Adekunle, A., & Olayimika Abolade, R. (2020). A Study on Rain Rate Prediction of Southwestern Nigeria. Physical Science International Journal, 23(4), 1-12. https://doi.org/10.9734/psij/2019/v23i430166
Original Research Article


Wikipedia. Rain Fade; 2017.
Available:https://simple.m.HYPERLINK "wikipedia.org/wiki/Rain"
(Accessed on May 2017)

Perez-Garcia N, Silva-Mello LAR. Improved method for prediction of rain attenuation in terestial links. Reasearch Gate. 2004;40(11):683-684.

Ajayi GO, Feng S, Radicella SM, Reddy, BM. Hand book on radio propagation related to satellite communications in tropical and subtropical countries. U.R.S. I Standing Committee on Developing Countries, UNESCO and ICTP; 1996.

Mandeep JS, Allnut JE. Comparison of rainfall properties on VHF & UHF bands in Krojak 2. Progress in Electromagnetic Research. 2007;76:65–74.

Pratt T, Bostian C, Allnut J. Satellite communication, Second edition. Wiley India Pvt. Ltd. 2006;536.

International Telecommunication Union Radio communication, ITU-R. Specific attenuation model for rain for use in prediction methods. Recommendation ITU-RP. 2005;838-3.

Moupfouma F. Electromagnetic waves attenuation due to Rain: A prediction model for terrestrial or LOS SHF and EHF radio communication links. Journal of Infrared, Millimeter Terahertz Waves. 2009;3(6):622-632.

Adenugba DA, Ajewole MO, Balogun F. Short term rain intensity statistics in Nigeria. Nigeria Journal of Space Research. 2005;2:167-174.

Obiyemi OO, Ojo JS, Ibiyemi TS. Performance analysis of rain rate models for microwave propagation designs over tropical climate; 2014.

Salonen ET, Poiares-Baptista JPV. A new global rainfall rate model. Proceedings of the 10th International Conference. On Antenna and Propagation; 1997.

Lin S. 11-GHz radio: Nationwide long-term rain rate statistics and empirical calculation of 11-GHz microwave rain attenuation. Bell System Technology Journal. 1977;56(9): 1581-1604.

Paulson KS, Gibbins CJ. Rain models for the prediction of fade durations at millimetre wavelengths. IEE Proc- Microw. Antennas Propug. 2000;147(6): 431-436.

International Telecommunication Union Radio communication, ITU-R. Characteris-tics of Precipitation for Propagation Modelling, Recommendation ITU-R P. 2012;837-6.

Crane RK. Electromagnetic wave propagation through rain. UK: John Wiley & Sons Series; 1996.

Laws JO, Parsons DA. The relation of raindrop size to intensity. Trans-America Geophysics Union. 1943;24(Part II):452- 460.

Ajayi GO, Ofoche EBC. Some tropical rainfall rate characteristics at Ile-Ife for microwave and millimeter wave application. J. of Climate and Applied Meteor. 1983;23:562-567.

Ajayi GO, Ezekpo SUB. Development of climatic maps of rainfall rate and attenuation for microwave applications in Nigeria. Niger. Eng. 1988;23(4):13–30.

Ojo JS, Ajewole MO, Sarkar SK. Rain rate and rain attenuation prediction for satellite communication in Ku and Ka bands over Nigeria. Progress In Electromagnetics Research B. 2008;5:207-223.

Semire FA, Raji TI. Characteristics of measured rainfall rate at Ogbomoso, Nigeria for microwave applications. Journal of Telecommunication and Information Technology. 2011;2:85-89.

Umeh CD. Determination of rain attenuation of microwave signals in Akure, Ondo State using the International Telecommunication Union of Radio Communication (ITU-R) Model. Thesis, University of Nigeria, Department of Physics and Astronomy, Nsukka; 2010.

Falodun SE, Okeke P. Radiowave propagation measurements in Nigeria (preliminary reports). Theoretical and Applied Climatology Journal. 2013;113(1-2).

Omotosho TV, Oluwafemi CO. One-minute rain rate distribution in Nigeria derived from TRMM satellite data. Journal of Atmospheric and Solar-Terrestrial Physics. 2009;71:625–633.

Olurotimi EO, Ojo JS. Testing Rainfall Rate Models for Rain Attenuation Prediction Purposes in Tropical Climate; 2007.

Semire FA, Rosmiwati MM, Omotosho TV, Ismail W, Mohamad N, Mandeep JS. Analysis of cumulative distribution function of 2-year rainfall measurements in Ogbomoso, Nigeria. International Journal of Applied Science and Engineering. 2012;10 (3):171-179.

Odjugo PA. An analysis of rainfall pattern in Nigeria. Global J. Environ. Sci. 2005; 4(2):139-145.

FEWS NET/USGS CHIRPS. Nigeria special Report: Famine Early Warining Systems Network; 2016.
(Retrieved 2017)

Semire FA, Rosmiwati MM. Development of rain rate prediction model for Nigeria. Canadian Journal of Pure and Applied Sciences. 2011;5(3):1721- 1728.

Huzak M. Chi-square distribution. In: Lovric M. (eds) International Encyclopedia of Statistical Science. Springer, Berlin, Heidelberg; 2011.

Mandeep JS. Comparison of rain rate models for equatorial climate in South East Asia. Geofizika. 2011;28:265-274.

Rice P, Holmberg N. Cumulative time statistics of surface-point rainfall rate. IEEE Transactions on Communications. 1973; 1131–1136.

Ito C, Hosaya Y. Proposal of a global conversion method for different integration time rain rates by using m distribution and regional climatic parameters. Electronics and Communications in Japan, Part 1. 2006;89(4):1–9.

Moupfouma F, Martin L. Modelling of the rainfall rate cumulative distribution for the design of satellite and terrestrial communication systems. Int. J. of Satellite Comm. 1995;13(2):105-115.