Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall

In meteorological data, lots of variables have annual, seasonal or diurnal cycles. These would be based on different climatic patterns in different seasons rising sea levels. The delta change approach is one of the statistical downscaling methods that used to downscale global climate model data in o...

Full description

Bibliographic Details
Main Author: Abdul Halim, Syafrina
Format: Article
Language:English
Published: Blue Eyes Intelligence Engineering & Sciences Publication 2019
Online Access:http://psasir.upm.edu.my/id/eprint/81086/
http://psasir.upm.edu.my/id/eprint/81086/1/DELTA.pdf
_version_ 1848859019530207232
author Abdul Halim, Syafrina
author_facet Abdul Halim, Syafrina
author_sort Abdul Halim, Syafrina
building UPM Institutional Repository
collection Online Access
description In meteorological data, lots of variables have annual, seasonal or diurnal cycles. These would be based on different climatic patterns in different seasons rising sea levels. The delta change approach is one of the statistical downscaling methods that used to downscale global climate model data in order to use it as a future input for hydrological models and flood risk assessment. In this work, a non-stationary GEV model with cyclic covariate structure for modelling magnitude and variation of data series with some degrees of correlation for real-world applications is proposed. All extreme events were calculated assuming that maximum annual daily precipitations follow the GEV distribution. The method makes it possible to identify and estimate the impacts of multiple time scales-such as seasonality, interdecadal variability, and secular trends-throughout the area, scale, and shape parameters of extreme sea level probability distribution. The incorporation of seasonal effects describes a huge amount of data variability, permitting the methods involved to be estimated more efficiently. Next, the technique of deltachange was implemented to the mean annual rainfall and also the regular rainfall occurrences of 5, 10, 20, 50 and 100 years of return. The capability of the proposed model will be tested to one rainfall station in Sabah. The new model suggesting improvement over the stationary model based on the p-value which is highly significant (approximate to 0). GEV model with cyclic covariate on both location and scale parameters is able to capture the seasonality factor in rainfall data. Hence, a reliable delta-change model has been developed in this study. This could produce more accurate projection of rainfall in the future.
first_indexed 2025-11-15T12:22:41Z
format Article
id upm-81086
institution Universiti Putra Malaysia
institution_category Local University
language English
last_indexed 2025-11-15T12:22:41Z
publishDate 2019
publisher Blue Eyes Intelligence Engineering & Sciences Publication
recordtype eprints
repository_type Digital Repository
spelling upm-810862020-10-12T07:34:42Z http://psasir.upm.edu.my/id/eprint/81086/ Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall Abdul Halim, Syafrina In meteorological data, lots of variables have annual, seasonal or diurnal cycles. These would be based on different climatic patterns in different seasons rising sea levels. The delta change approach is one of the statistical downscaling methods that used to downscale global climate model data in order to use it as a future input for hydrological models and flood risk assessment. In this work, a non-stationary GEV model with cyclic covariate structure for modelling magnitude and variation of data series with some degrees of correlation for real-world applications is proposed. All extreme events were calculated assuming that maximum annual daily precipitations follow the GEV distribution. The method makes it possible to identify and estimate the impacts of multiple time scales-such as seasonality, interdecadal variability, and secular trends-throughout the area, scale, and shape parameters of extreme sea level probability distribution. The incorporation of seasonal effects describes a huge amount of data variability, permitting the methods involved to be estimated more efficiently. Next, the technique of deltachange was implemented to the mean annual rainfall and also the regular rainfall occurrences of 5, 10, 20, 50 and 100 years of return. The capability of the proposed model will be tested to one rainfall station in Sabah. The new model suggesting improvement over the stationary model based on the p-value which is highly significant (approximate to 0). GEV model with cyclic covariate on both location and scale parameters is able to capture the seasonality factor in rainfall data. Hence, a reliable delta-change model has been developed in this study. This could produce more accurate projection of rainfall in the future. Blue Eyes Intelligence Engineering & Sciences Publication 2019-07 Article NonPeerReviewed text en http://psasir.upm.edu.my/id/eprint/81086/1/DELTA.pdf Abdul Halim, Syafrina (2019) Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall. International Journal of Recent Technology and Engineering, 8 (2S2). pp. 158-161. ISSN 2277-3878 https://www.ijrte.org/wp-content/uploads/papers/v8i2S2/B10290782S219.pdf 10.35940/ijrte.B1029.0782S219
spellingShingle Abdul Halim, Syafrina
Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title_full Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title_fullStr Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title_full_unstemmed Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title_short Delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
title_sort delta change method with cyclic covariate generalized extreme value model for downscaling extreme rainfall
url http://psasir.upm.edu.my/id/eprint/81086/
http://psasir.upm.edu.my/id/eprint/81086/
http://psasir.upm.edu.my/id/eprint/81086/
http://psasir.upm.edu.my/id/eprint/81086/1/DELTA.pdf