Sources of moisture for Central America based on a langrangian approachvariability, contributions to precipitation and transport mechanisms

Resumo

The present work pressents a long term analysis of the sources of moisture for precipitation over Central America based on a Lagrangian analysis method. The importance of the water vapour in the climate system is presented in order to introduce the importance of the sources and sinks of moisture for understanding climate. The main global sources of moisture are presented to highlight the importance of studying regions like the Intra Americas Sea (IAS). The state of ghe art of the regional climate system is presented through a summary of the main features of regional climate, their importance and the sensitivity to the forcing of selected signals. The advantage of using Lagrangian approaches is ipresented followed by an introduction to the problem of the transport of moisture in the IAS region is presented with the main works that have been done. The objectives of this study and the main research activities are also given as a closure to the introductory part. The second part of this work is composed by the description of the methodology and datasets used for the study, followed by the long term analysis of the sources of moisture for Central America and their variability and information on the contributions to precipitation from the individual sources. The three dimensional structure of the moisture transport is explored, jointly with further discussions on the mechanisms that lead the moisture transport process. The role of the Caribbean Low Level Jet (CLLJ) as a moisture conveyor is analysed as well as its response to the vain variability modes affectin the IAS. A third and final part contains the summary of the main conclusions and results of this work closed by the proposal of the future research lines derived from the work herein presented.