Multi-source quantification of global water cycle components

Mijael Rodrigo Vargas Godoy

Doctoral thesis

Abstract:

Evolving in tandem with civilization and technology, our understanding of the water cycle has spurred continuous refinement in quantification methods. However, the uncertainty revealed in the first attempts to unify different data products has hindered this unique opportunity to obtain a robust quantification of the water cycle. Consequently, it remains a challenge to constrain the variability stemming from measurements by various sources, which will help us understand the effect of global warming on water resources in general. Therefore, this dissertation aimed to improve the understanding of the global water cycle and advance multi-source quantification by: (a) providing an in-depth recapitulation of global water cycle research advancements regarding data sources and quantification methods; (b) enhancing the evaluation of climate reanalyses by proposing a comprehensive framework to study changes in the water cycle; (c) developing a powerful tool that eases the download, exploration, processing, and visualization of an all-around global precipitation data collection; and (d) comprehensively integrating the previous findings and tools to introduce a method for benchmarking multi-source hydroclimatic data fusion based on water cycle budget closure. The results demonstrated that: (a) the consistency of global water cycle quantification has improved despite significant uncertainty challenges associated with spatiotemporal variability; (b) the signal-to-noise ratio of traditional metrics versus the natural variability is low, and as a consequence, the fluctuations in the water cycle are harder to detect; (c) there is significant heterogeneity among data distribution and formats, deterring robust quantification of global water cycle climatology; and (d) the proposed framework based on water cycle budget closure easily and quickly filters out data combinations that provide implausible results. Therefore, this dissertation improved the understanding of multi-source quantification methods and advanced frameworks for evaluating global and regional water cycle dynamics.

Keywords

Water Cycle Changes, Multi-Source Quantification, Hydroclimatology, Global Water Cycle

Language used: English

Date on which the thesis was submitted / produced: 1. 2. 2024

Thesis defence

• Supervisor: doc. Mgr. Ing. Ioannis Markonis, Ph.D.
• Reader: Michal Kuráž, doc. Ing., Ph.D., Christoforos Pappas, externi, Peter Greve, externi

Czech University of Life Sciences Prague

Faculty of Environmental Sciences

Doctoral programme / field:
Landscape Engineering / Environmental Modelling