Attaching a 'floating' tree-ring chronology to ice core records that cover the abrupt Younger Dryas cold interval during the last glacial termination provides a better estimate of the onset and duration of the radiocarbon anomaly. The chronology suggests that marine records may be biased by changes in the concentration of radiocarbon in the ocean, which may affect the accuracy of a popular radiocarbon calibration program during this interval.

Destruction of the Earth's ozone shield due to the release of hydrogen sulphide and methane has been suggested as a cause of mass extinctions during periods of ocean anoxia over the past two billion years. This mechanism does not explain the end-Permian mass extinction, according to simulations with a two-dimensional atmospheric chemistry-transport model, which show that the ozone shield remains intact even with massive releases of hydrogen sulphide and methane.

The Gulf Stream transports large amounts of heat from the tropics to middle and high latitudes, and thereby affects weather phenomena such as cyclogenesis and low cloud formation.

Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter grou

Denitrifying bacteria and hungry plants do sterling work in disposing of the nitrates that we pump into rivers and streams.