The Importance of Water

The Water Cycle

In this course, Professor Joseph Holden (University of Leeds) explores the water cycle and hydrological processes. In the first module, we think about some of water’s key properties, and its importance in human and physical geographical processes. The second module surveys the major stores of water on Earth, the processes by which water is transferred between them, and disparities in access to freshwater resources. In the third module, we look at the impacts of climate change and changes in land use on the water cycle. In the fourth and fifth modules, we turn to drainage basins, looking firstly at the processes by which water moves into river channels, and secondly at variations in river flow and flood risk. We conclude with a sixth module on the impacts of urban development on the water cycle, and how humans manage and control water flows.

The Importance of Water

In this module, we think about the importance of water in both social and physical processes, focusing on three key features of water and their impacts: (i) its thermal properties – water is densest when it is a liquid and requires a large amount of energy to change temperature, which is very significant for rock weathering and the climate system; (ii) its property of surface tension, which enables the important process of capillary action; (iii) its chemical properties – water is a highly effective solvent, meaning that it carries substances vital for life and drives oceanic carbon storage.