Trace the possible paths of a water molecule through the hydrological cycle and consider the measurements that need to be made to determine the quantities of water involved in the various transformations.
What processes lead to phase changes of water in the atmosphere and what are some of their consequences?
What is the significance of clouds in the global water balance?
Compare the moisture balance of an air column and that of a small drainage basin.
What are the various statistics used to characterize rainfall events and for what different purposes are they important?
Consider how an annual water budget diagram might differ between a wet year and a dry year at the same location.
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Plate 1 Visible image of Africa, Europe and the Atlantic Ocean taken by METEOSAT on 19 August 1978 at 11:55 hours GMT. An anticyclone is associated with clear skies over Europe and the Mediterranean, while frontal-wave cyclones are evident in the North Atlantic. Cloud clusters appear along the oceanic intertropical convergence zone (ITCZ) and there are extensive monsoon cloud masses over equatorial West Africa. Less organized cloud cover is present over East Africa. The subtropical anticyclone areas are largely cloud-free but possess trade wind cumulus, particularly in the southeast trade wind belt of the South Atlantic. The highly reflective desert surfaces of the Sahara are prominent (METEOSAT image supplied by the European Space Agency).
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