Abrupt and sudden climatic transitions and fluctuations: a review

Abstract

This review paper summarizes recent research work on abrupt climatic changes and oscillations. The climatic system is viewed as a dissipative, highly non-linear system, under non-equilibrium conditions, and, as such, should be expected to have some unusual properties. These unusual properties include bifurcation points with marked instability just before the point, magnification of semi-periodic oscillations around bifurcation points, and variations in the strength of teleconnections with distance from equilibrium. These properties are discussed and illustrated for the climatic system using both the historical, Holocene and glacial climatic records. It is found that there are abrupt climatic changes and oscillations on all time-scales. The amplitudes and frequencies of climate variability and teleconnections are found to vary between different time periods. A number of persistent oscillations exist, particularly one about 1500 years, but their amplitudes vary considerably between time periods. The Holocene appears to be no more climatically benign than the similar period in the Eemian. The importance of the North Atlantic thermohaline circulation for generating abrupt climatic changes in Europe, particularly in association with sudden pulses of fresh water, is illustrated. The concept of antiphase temperature changes between the North and South Atlantic is discussed. Externally generated abrupt climatic deteriorations owing to explosive volcanic eruptions and variations in solar irradiance are also discussed.

Tipping elements in the Earth's climate system

“…Previous reviews (6)(7)(8)(9)(10) have defined ''abrupt climate change'' as occurring ''when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause'' (8), which is a case of bifurcation (i.e., one that focuses on equilibrium properties, implying some degree of irreversibility). We have formulated a much broader definition of a tipping element, because (i) we wish to include nonclimatic variables; (ii) there may be cases where the transition is slower than the anthropogenic forcing causing it; (iii) there may be no abruptness, but a slight change in control may have a qualitative impact in the future; and (iv) for several important phase changes, state-of-the-art models differ as to whether the transition is reversible or irreversible (in principle).…”

The ‘Little Ice Age’ – only temperature?

“…During the Holocene, a number of abrupt and widespread climatic variations are recorded around the world (e.g., Lockwood, 2001). In the North Atlantic region, it has been claimed that these changes have an approximate 1500 (1470 6 500)-yr periodicity (Bond et al, 1997;Campbell et al, 1998).…”

Predicting Climate Tipping as a Noisy Bifurcation: A Review

“…Work at the beginning of this century which set out to define and examine climate tipping [Rahmstorf, 2001;Lockwood, 2001;National Research Council, 2002;Alley et al, 2003;Rial et al, 2004] focused on abrupt climate change: namely when the Earth system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause, with some degree of irreversibility. As we noted in Sec.…”