Logo image
Modelling daily rainfall with climatological predictors: Poisson-gamma generalized linear modelling approach
Journal article   Peer reviewed

Modelling daily rainfall with climatological predictors: Poisson-gamma generalized linear modelling approach

Rossita M Yunus, Md Masud Hasan, Nuradhiathy A Razak, Yong Z Zubairi and Peter K Dunn
International Journal of Climatology, Vol.37(3), pp.1391-1399
2017
url
https://doi.org/10.1002/joc.4784View
Published Version

Abstract

EDM Tweedie Poisson-gamma model rainfall modelling
Generalized linear models (GLMs) are used in understanding the impact of predictors on a dependent variable. The aim of this study is to fit GLMs to daily rainfall totals using potential predictors. First, the appropriate probability distributions within a specific family, the Tweedie family, were determined for daily rainfall totals from four stations of Peninsular Malaysia from 1983 to 2012. Within the Tweedie family, the Poisson Gamma (PG) distribution was found appropriate to model both components: occurrence (dry/wet days) and amount (rainfall totals on wet days) of rainfall simultaneously. Then, the PG-GLMs were fitted to rainfall data with a sine term, a cosine term, lagged rainfall, NINO3.4 and Southern oscillation index (SOI) as predictors. Finally, the models were compared using the Likelihood ratio test and the Akaike information criterion. Initially, considering the cyclic pattern of rainfall data, models with only sine and cosine terms (the base model) were fitted. Then the lagged rainfall and climatological variables were added each time to the base model. Diagnostic QQ plots indicate that the models fit the data well. The models were fitted using the first 60% of data and validated using the remainder. The models capture the various characteristics of observed datasets reasonably well. Including single climatological variables in the model significantly improves the fit compared to the base model with lagged rainfall (except for the south-east coastal station, Mersing), however, including both climatological predictors in the same model does not improve the model significantly. The model with SOI is only favoured for the east coastal station, Kuala Terengganu, and the model with NINO3.4 fits better to the inland and west coastal stations. The models are useful in understanding the impact of the studied climatological variables and to predict the amount and probability of rainfall.

Details

Metrics

4 File views/ downloads
711 Record Views

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types
Domestic collaboration
International collaboration
Web Of Science research areas
Meteorology & Atmospheric Sciences

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

#6 Clean Water and Sanitation
#13 Climate Action
#14 Life Below Water

Source: InCites

Logo image