text: Since evaporation causes oceanic and terrestrial waters to have a different ratio of O to O, the Dole effect will reflect the relevant importances of land-based and marine photosynthesis. The complete removal of land-based productivity would result .
  The stability (to within 0.5‰) of the atmospheric O to O ratio with respect to sea surface waters since the last interglacial (the last 130 000 years), as derived from ice cores, suggests that terrestrial and marine productivity have varied together during this time period.
  Millennial variations of the Dole effect were found to be related to abrupt climate change events in the North Atlantic region during the last 60 kyr (1kyr=1000years). High correlations of the Dole effect to speleothem δO, an indicator for monsoon precipitation, suggest that it is subject to changes in low-latitude terrestrial productivity. Orbital scale variations of the Dole effect, characterized by periods of 20-100 kyr, respond strongly to Earth's orbital eccentricity and precession, but not obliquity.
  The Dole effect can also be applied as a tracer in sea water, with slight variations in chemistry being used to track a discrete "parcel" of water and determine its age.