standard Tipping points and abrupt warming in the arctic

Dangerous climate change has been a reality for ecosystems (including people) in the Arctic.  The IPCC has provided five major concerns for climate change in this region of the world:

  • Risks to unique and threatened systems (Risk of losing unique ecological and social systems)
  • Risk of extreme weather events (Extreme events with substantial consequences for societies and natural systems)
  • Distribution of impacts (Spatial scale of impacts)
  • Aggregate damages (Monetary damages or monetary losses, and lives affected or lives lost)
  • Risks of large-scale discontinuities (Likelihood of reaching tipping points [emphasis added])

Researchers along with the media have debated about the existence of ‘tipping points’ in the Earth’s climate system(s), that may not only be present in physical systems, but biological and even social systems as well.  The term ‘tipping point’ itself is generally speaking often not defined very well and is known to exhibit multiple meanings in scientific literature and the media.  This is the focus of one of the programmes of research part of a unique project called Tipping Points and while much of the work on climate change itself is ongoing there have been some clues as to how the tipping point metaphor has reached a peak in popularity, with likely many more to come.

If tipping point means crossing a critical threshold in which a system enters substantial irreversible change that causes it to move into an entirely new state, there may be precursors or early warning signals of such change.  This is exactly what some climate researchers are after because as shown in the graphic below using data from the National Snow & Ice Data Center in the US, there is not only one but many ‘tipping points’ to consider when studying variability in the Arctic’s climate.

Tipping elements: that involve ice melting (white); involve changes in ocean circulation (often coupled to sea ice and/or atmospheric circulation) (aqua green); and involve biome change (dark green). Nature Climate Change

In a recent article published in Nature Climate Change, researchers argue that tipping elements — ‘large-scale components of the Earth system that can exhibit a tipping point’ — not only exist, but are interconnected, increasing the risk of extreme weather events:

The array of tipping elements in the Arctic are not independent — they are causally connected to one another, and to other areas for concern. Warming of the Arctic region is proceeding at three times the global average, and a new ‘Arctic rapid change’ climate pattern has been observed in the past decade. Loss of Arctic sea ice has been tentatively linked to extreme cold winters in Europe (another reason for concern, namely risks of extreme weather events). Near complete loss of the summer sea ice, as forecast for the middle of this century, if not before, will probably have knock-on effects for the northern mid-latitudes, shifting the jet streams and storm tracks. Several tipping elements have already been set in motion and changes are accelerating. But, are they about to reach their tipping points? Nature Climate Change

But this research team along with other scientists argue that tipping points need not be irreversible, although they may be difficult to reverse in practice. There is a great deal of uncertainty regarding modelling sea ice loss in the Arctic with quite large inconsistencies between observed and predicted sea ice loss.

Observed vs modelled sea ice loss from IPCC (

If tipping points in the Arctic’s climate do indeed exist then they are likely extremely difficult to predict and require expertise from multiple scientific fields in order to find solutions for adaptation.   If in the case of the Arctic where the variability in ice extent has increased a great deal since 2006, could this be one of those warning signals?  Researchers point out that ‘the acceleration of sea-ice decline around 1996 was preceded by an increase in sea-ice variability nearly a decade beforehand’.

But how do you know if the variability you’re measuring is an early warning signal?  There are levels of complexity here that demand not only expertise from physical scientists and mathematicians working together, but social scientists as well, especially regarding how tipping points are understood, defined and interpreted in society.  It would appear that tipping point is here to stay (at least for now) in scientific research as well as in journalism, but this does not mean that it must be confined to an alarmist or apocalyptic view.  Rather, it has a clear advantage in understanding the role of science in mitigating climate change, especially in terms of exploration and obtaining the knowledge needed for overcoming unforeseeable odds, which is often what scientific inquiry does best.  The science of tipping points could be a triumph rather than a forecast for disaster, if appropriate action is taken.

Keeping this idea in mind, here is the first video on the field research of the Tipping Points project on uncovering climate transitions in the North Atlantic.

Further Reading and References

Abrupt climate change in the Arctic. Nature Climate Change

Tipping Elements in the Arctic Ecosystem.  AMBIO

Tipping Points Annual Report. IHRR

Duarte, C., Lenton, T., Wadhams, P., & Wassmann, P. (2012). Abrupt climate change in the Arctic Nature Climate Change, 2 (2), 60-62 DOI: 10.1038/nclimate1386

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