AS ARCTIC sea ice hits a record low, scientific focus is turning to climate ''tipping points'' - a threshold that, once crossed, cannot be reversed and will create fundamental changes to other areas.

''It's a trigger that leads to more warming at a regional level but also leads to flow-on effects through other systems,'' Will Steffen, the chief adviser on global warming science to Australia's Climate Commission, said.

There are about 14 known ''tipping elements'', according to a paper published by the US Proceedings of the National Academy of Sciences.

In the case of the Arctic ice cap, less ice means less white surface to reflect heat and more dark water to soak it up. This leads to higher temperatures, which scientists say will unlock more ancient greenhouse gases frozen into ocean depths and permafrost, speeding climate change, interfering with ocean currents, rainfall patterns and weather.