. Rainfall sampler. Scientist collects the water from a rainfall sampler used in climate research. The sampler only opens during periods of rain. The water is removed, refrigerated, and sent for analysis. Particles in the water, especially those containing sulphur & nitrogen, may have affected the properties of the cloud that the rain came from. Measurement of the relative amounts of the oxygen-18 and hydrogen-2 (deuterium) atomic isotopes in the water helps to determine the global circulation of water. Photo- graphed at the Cape Grim Baseline Air Pollution Station in Tasmania, Australia. MODEL RELEASED