Bias correction of daily chirps-V2 rainfall estimates in Ghana

A wide range of economic sectors in the Ghana, including agriculture, health care, and energy, heavily rely on climate data; as a result, having access to reliable climate data is crucial for research and economic growth yet rainfall gauge data in Ghana scarcely available, therefore, researchers ten...

Descripción completa

Detalles Bibliográficos
Autor principal: Johnson, R.
Formato: Tesis
Lenguaje:Inglés
Publicado: Kwame Nkrumah University of Science and Technology 2022
Materias:
Acceso en línea:https://hdl.handle.net/10568/128521
_version_ 1855524586477584384
author Johnson, R.
author_browse Johnson, R.
author_facet Johnson, R.
author_sort Johnson, R.
collection Repository of Agricultural Research Outputs (CGSpace)
description A wide range of economic sectors in the Ghana, including agriculture, health care, and energy, heavily rely on climate data; as a result, having access to reliable climate data is crucial for research and economic growth yet rainfall gauge data in Ghana scarcely available, therefore, researchers tend to depend on satellite estimates for hydrological studies and impact assessments. However, biases in satellite rainfall estimates and the ability for these rainfall products to effectively capture rainfall indices poses major issues for researcher and various key stakeholders. In this study, CHIRPS-v2 rainfall estimates were bias corrected using four (4) different bias correction algorithms (Linear Scaling (LS), Local Intensity Scaling (LOCI), Quantile Mapping (QM) and Bias Correction and Spatial Disaggregation (BCSD) methods) using 28 selected stations across Ghana and spatio-temporally over the entire country. At the station level the Linear Scaling method produced the best results, although after correction no significant changes were observed especially on a daily scale, using the day to compute seasonal indices yielded improved results. Spatio-temporally, The BCSD approach outperformed the other bias corrective correction strategies, most likely because it can capture the development of the average rainfall while matching statistical moments. The rainfall seasonal indices were then calculated from bias corrected CHIRPS-v2 data and the spread and the distributing of the various indices were well represented. Moreover, the extreme rainfall analysis produced results consistent with gauge values measured at the same time duration. Bias correction was able to minimize the errors and uncertainties that existed within the daily CHIRPS-v2 dataset, making it more suitable to derive agro-advisories.
format Tesis
id CGSpace128521
institution CGIAR Consortium
language Inglés
publishDate 2022
publishDateRange 2022
publishDateSort 2022
publisher Kwame Nkrumah University of Science and Technology
publisherStr Kwame Nkrumah University of Science and Technology
record_format dspace
spelling CGSpace1285212023-02-15T07:29:20Z Bias correction of daily chirps-V2 rainfall estimates in Ghana Johnson, R. weather forecasting climate change food security ghana A wide range of economic sectors in the Ghana, including agriculture, health care, and energy, heavily rely on climate data; as a result, having access to reliable climate data is crucial for research and economic growth yet rainfall gauge data in Ghana scarcely available, therefore, researchers tend to depend on satellite estimates for hydrological studies and impact assessments. However, biases in satellite rainfall estimates and the ability for these rainfall products to effectively capture rainfall indices poses major issues for researcher and various key stakeholders. In this study, CHIRPS-v2 rainfall estimates were bias corrected using four (4) different bias correction algorithms (Linear Scaling (LS), Local Intensity Scaling (LOCI), Quantile Mapping (QM) and Bias Correction and Spatial Disaggregation (BCSD) methods) using 28 selected stations across Ghana and spatio-temporally over the entire country. At the station level the Linear Scaling method produced the best results, although after correction no significant changes were observed especially on a daily scale, using the day to compute seasonal indices yielded improved results. Spatio-temporally, The BCSD approach outperformed the other bias corrective correction strategies, most likely because it can capture the development of the average rainfall while matching statistical moments. The rainfall seasonal indices were then calculated from bias corrected CHIRPS-v2 data and the spread and the distributing of the various indices were well represented. Moreover, the extreme rainfall analysis produced results consistent with gauge values measured at the same time duration. Bias correction was able to minimize the errors and uncertainties that existed within the daily CHIRPS-v2 dataset, making it more suitable to derive agro-advisories. 2022-10 2023-02-08T12:49:04Z 2023-02-08T12:49:04Z Thesis https://hdl.handle.net/10568/128521 en Limited Access Kwame Nkrumah University of Science and Technology Johnson, R. (2022). Bias correction of daily chirps-V2 rainfall estimates in Ghana. Kumasi, Ghana: Kwame Nkrumah University of Science and Technology, (105 p.).
spellingShingle weather forecasting
climate change
food security
ghana
Johnson, R.
Bias correction of daily chirps-V2 rainfall estimates in Ghana
title Bias correction of daily chirps-V2 rainfall estimates in Ghana
title_full Bias correction of daily chirps-V2 rainfall estimates in Ghana
title_fullStr Bias correction of daily chirps-V2 rainfall estimates in Ghana
title_full_unstemmed Bias correction of daily chirps-V2 rainfall estimates in Ghana
title_short Bias correction of daily chirps-V2 rainfall estimates in Ghana
title_sort bias correction of daily chirps v2 rainfall estimates in ghana
topic weather forecasting
climate change
food security
ghana
url https://hdl.handle.net/10568/128521
work_keys_str_mv AT johnsonr biascorrectionofdailychirpsv2rainfallestimatesinghana