(a) The hydrologic cycle. Note the many and complex ways that water interacts with all Earth systems as it transforms and moves between solid, liquid, and vapour forms. (b) Quantifying average annual global water storage and exchange in the hydrologic cycle. The percentage of global water stored by various components of the water cycle is shown in blue bubbles, whereas the percentage of global water exchanged on an annual basis is given in yellow boxes. Orange arrows represent the relative sizes of the exchange. The accompanying tables also report the amounts of water stored or exchanged. The animation gives an overview of The Hydrologic Cycle.