Climate during periods prior to the development of measuring instruments, including historic and geologic time, for which only proxy climate records are available. Palaeoclimate
Climate for periods prior to the development of measuring instruments, including historic and geologic time, for which only proxy climate records are available. (Or geological climate.)
The sequence of climatic changes in geologic time. It shows a succession of oscillations between warm periods and ice ages, but superimposed on this are numerous shorter oscillations. The tendency to
regard the whole of a geologic period, lasting for 20 million years and more, as having a single type of climate is a great oversimplification, as is shown by the succession of glacial and interglacial periods in the Quaternary. Even the warm periods are known to have been made up of successions of climates of different degrees of warmth; but until much more information is available, it will not be possible to set out in detail the sequence of changes of the earlier paleoclimates.
Old sea ice, generally considered to be at least ten years old; it is nearly always a form of pressure ice and is often found in floebergs and in the pack ice of the central Arctic Ocean.