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Discusses a study by Richard Bintanja and colleagues who used a novel and elegant method to investigate further the ratio of oxygen isotopes contained in benthic foraminifera to explore past ice-volume variations. Challenge of disentangling the different contributions to the signal in benthic foraminifera, the fossilized remains of single-celled organisms that lived on or close to the ocean floor; Variation of the ratio of the oxygen isotopes [sup 18]O and [sup 18]O in the shells of benthic foraminifera with the depth of the sediments in which they are buried; Choosing the benthic isotope record that should be used to drive the model.

Presents a study of the oxygen-isotope values of two massive sulphate mineral deposits which show large isotopic anomalies despite being formed in surface environments. Origination of deposits in the central Namib desert and the sulphate-bearing Miocene volcanic ash-beds in North America; Questions regarding the source of the oxygen isotope; Possibility of the chemical origin of variable isotope anomalies on planets other than Earth.

The article discusses concentration level of isotopic gradients in rains. Topics include variations in rain hydrogen and oxygen gradients, effect of storms and water vapour on controlling the levels, and link between mountains and the gradients for understanding of past and present climatic changes. An image of water-vapour transport along a storm track in Denali National Park and Reserve in Alaska is presented.