Climate Change Analysis for Guinea Conakry with Homogenized Daily Dataset
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CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 ADVERTIMENT. L'accés als continguts d'aquesta tesi doctoral i la seva utilització ha de respectar els drets de la persona autora. Pot ser utilitzada per a consulta o estudi personal, així com en activitats o materials d'investigació i docència en els termes establerts a l'art. 32 del Text Refós de la Llei de Propietat Intel·lectual (RDL 1/1996). Per altres utilitzacions es requereix l'autorització prèvia i expressa de la persona autora. En qualsevol cas, en la utilització dels seus continguts caldrà indicar de forma clara el nom i cognoms de la persona autora i el títol de la tesi doctoral. No s'autoritza la seva reproducció o altres formes d'explotació efectuades amb finalitats de lucre ni la seva comunicació pública des d'un lloc aliè al servei TDX. Tampoc s'autoritza la presentació del seu contingut en una finestra o marc aliè a TDX (framing). Aquesta reserva de drets afecta tant als continguts de la tesi com als seus resums i índexs. ADVERTENCIA. El acceso a los contenidos de esta tesis doctoral y su utilización debe respetar los derechos de la persona autora. Puede ser utilizada para consulta o estudio personal, así como en actividades o materiales de investigación y docencia en los términos establecidos en el art. 32 del Texto Refundido de la Ley de Propiedad Intelectual (RDL 1/1996). Para otros usos se requiere la autorización previa y expresa de la persona autora. En cualquier caso, en la utilización de sus contenidos se deberá indicar de forma clara el nombre y apellidos de la persona autora y el título de la tesis doctoral. No se autoriza su reproducción u otras formas de explotación efectuadas con fines lucrativos ni su comunicación pública desde un sitio ajeno al servicio TDR. Tampoco se autoriza la presentación de su contenido en una ventana o marco ajeno a TDR (framing). Esta reserva de derechos afecta tanto al contenido de la tesis como a sus resúmenes e índices. WARNING. Access to the contents of this doctoral thesis and its use must respect the rights of the author. It can be used for reference or private study, as well as research and learning activities or materials in the terms established by the 32nd article of the Spanish Consolidated Copyright Act (RDL 1/1996). Express and previous authorization of the author is required for any other uses. In any case, when using its content, full name of the author and title of the thesis must be clearly indicated. Reproduction or other forms of for profit use or public communication from outside TDX service is not allowed. Presentation of its content in a window or frame external to TDX (framing) is not authorized either. These rights affect both the content of the thesis and its abstracts and indexes. UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 Abdoul Aziz Barry CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET A thesis submitted for the degree of Doctor of Philosophy at the University Rovira i Virgili, Tarragona- Spain Director: Dr. Enric Aguilar Anfrons GEOGRAPHY DEPARTMENT FACULTAT DE TURISME I GEOGRAFIA Centre for Climate Change (C3) Tortosa, 3rd October 2014 UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 ACKNOWLEDGEMENTS In the name of God, most Gracious, most Merciful. I gratefully acknowledge the funding received towards my PhD from the Centre for Climate Change C3 and the University Rovira i Virgili PhD fellowship. I would like to convey my heartfelt thanks to Campus Terres de l’Ebre and the Centre for Climate Change for offering me an ideal environment in which I felt free and could concentrate on my research. The data I have used comes from Guinea National Met Services. Heartfelt thanks and recognition to all those who have spent their life collecting these data. I am very grateful to my supervisor Dr. Enric Aguilar who accepted me as his Ph.D. student without any hesitation when I presented him my research proposal for his guidance and support. Enric guided me through every stage of my PhD research with great expertise, patience and good humors. He helped me conceptualize the thesis and provided R packages for data homogenization, climographs designing, and trends computation and analysis. I would like to express my gratitude and appreciation to Dr. Manola Brunet, director of C3, for her trust. I also remain indebted for her understanding and support during the times when I was really down. I would like to express my gratitude and appreciation to Alba, Dr. Constanta, Dr. Dimitri, Dr. Javier, Dr. Joan, Dr. Mercè, Dr. Peter, Elito, Núria, Olga and Rafa for either technical support or administrative support or Scientifics support or both. I would like to thank everyone in C3 for their friendship which has made working in the centre so enjoyable. I will recall Peter's Spanish lesson while he could have dedicate his valuable time to other purposes. My sincere gratitude is reserved for Professor Oliveras for his invaluable insights and suggestions. I wish I had met him twenty years ago. He is an inspiration. I am greatly indebted to my devoted wife Amanatou for her love and support without any complaint. Being both a mother and father while I was away has not been an easy task. To Aicha and Cire, I apologize for having left when you need me more. Climate change analysis for Guinea Conakry with homogenized daily dataset iv UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 ABSTRACT Though climate change assessments are important to allow countries to evaluate the changes and investigate consequences of climate extreme and variability on agriculture, water resources and other sectors to make appropriate decisions on mitigation and adaptation strategies, attempting to understand the climate changes on Africa is fraught with difficulties. Among these challenges is the lack of sufficiently long, high-quality and reliable climate records free of any non climatic jumps and/or shifts with a daily or higher time resolution. Thus, there is need assessing the quality of climate time series and correcting or excluding suspicious data and making adjustments for inhomogeneities wherever they are needed. In this thesis, Guinea's 12 synoptic weather stations daily minimum and daily maximum temperatures and daily precipitation data have been carefully quality controlled using the RClimdex-ExtraQC routines. These routines contain graphical and statistical information to quality control single time series. The values identified as potentially erroneous have been carefully scrutinized and a subjective decision has been made to validate, correct or set them to missing. The resulted quality controlled dataset free of any kind of suspicious data record has been homogenized using HOMER. Chosen indices from ETCCDI and ET-CRSCI indices have been calculated using ET- CRSCI newly developed ClimPact R package. Annual and seasonal temperatures and precipitations indices have also been computed. Additionally, eight nationwide averaged climate extremes indices, the nationwide averaged annual Tx mean and Tn mean and total precipitation indices have been use to detect teleconnection between climate indices and SOI indices. A nonparametric trend analysis is then performed for three overlapping periods, with different starting years 1941, 1961 and 1971 but all ending the same 2010 year. The result suggested that coherent spatial patterns of statistically significant warming changes have emerged in both Tx and Tn related extremes indices for all periods and season. Indices based on daily precipitation data showed more mixed patterns of change UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015Abstract but, in general, significant drying patterns have been seen in most of the former periods' daily precipitation related indices while over the recent period analyses suggested non- significant changes towards wetter conditions. Overall, there have been no spatially coherent changes in extreme rainfall events across Guinea as a whole for the study period, but changes in extreme precipitation events have occurred on local scales. There are signs that cooler and wetter conditions appeared to be associated with the La Niña years. vii Climate change analysis for Guinea Conakry with homogenized daily dataset UNIVERSITAT ROVIRA I VIRGILI CLIMATE CHANGE ANALYSIS FOR GUINEA CONAKRY WITH HOMOGENIZED DAILY DATASET. Abdoul Aziz Barry Dipòsit Legal: T 262-2015 TABLE OF CONTENTS Acknowledgements........................................................................................................................................iv Abstract ..........................................................................................................................................................vi Table of contents..........................................................................................................................................viii