Climate Tipping Points Could Topple Like Dominoes, Warn Scientistshttps://www.theguardian.com/environment/2021/jun/03/climate-tipping-points-could-topple-like-dominoes-warn-scientistsNew research examined the interactions between ice sheets in West Antarctica, Greenland, the warm Atlantic Gulf Stream and the Amazon rainforest. The scientists carried out 3 million computer simulations and found domino effects in a third of them, even when temperature rises were below 2°C, the upper limit of the Paris agreement.
The study showed that the interactions between these climate systems can lower the critical temperature thresholds at which each tipping point is passed. It found that ice sheets are potential starting points for tipping cascades, with the Atlantic currents acting as a transmitter and eventually affecting the Amazon.
“We provide a risk analysis, not a prediction, but our findings still raise concern,” said Prof Ricarda Winkelmann, at the Potsdam Institute for Climate Impact Research (PIK) in Germany. “[Our findings] might mean we have less time to reduce greenhouse gas emissions and still prevent tipping processes.”
The level of CO2 in the atmosphere required to push temperatures beyond the thresholds could be reached in the very near future, she said. “In the next years or decades, we might be committing future generations to really severe consequences.” These could include many metres of sea-level rise from ice melting, affecting scores of coastal cities.
... In May, scientists reported that a significant part of the Greenland ice sheet was on the brink of a tipping point. A 2019 analysis led by Prof Tim Lenton at the University of Exeter suggested the world may already have crossed a series of climate tipping points, resulting in what the researchers called “an existential threat to civilisation”.
The climate crisis may also mean much of the Amazon is close to a tipping point, at which carbon-storing forest is replaced by savannah, researchers have warned. The ocean currents of the Atlantic Meridional Overturning Circulation (AMOC), of which the Gulf Stream is an important part and keeps western Europe mild, are at their weakest in more than a millennium.
Nico Wunderling, et.al.,
Interacting tipping elements increase risk of climate domino effects under global warming,
(2021)
https://esd.copernicus.org/articles/12/601/2021/https://doi.org/10.5194/esd-12-601-2021... Tipping cascades occur when two or more tipping elements transgress their critical thresholds for a given temperature level (see Sect. 2.5). We evaluate the associated risk as the share of ensemble simulations in which such tipping cascades are detected. For global warming up to 2.0 ∘C, tipping occurs in 61 % of all simulations (Fig. 5a). This comprises the tipping of individual elements (22 %) as well as cascades including two elements (21 %), three elements (15 %) and four elements (3 %; see Fig. 5b).