A scientific study reveals the importance of feedback loops in the climate that may be undermining the effectiveness of anti-pollution measures
What can cause the fluttering of a butterfly? “A tornado in Texas”. At least that’s how the mathematician and meteorologist Edward Lorenz responded after assuming the movement of the wings of this insect in Brazil. A quote made into a movie on countless occasions and that goes back to the Chinese proverb: “The fluttering of a butterfly’s wings can be felt on the other side of the world.” And, also, to the theory of chaos. A fact that is transferred to the fight against climate change is that a fire in Chile can cause less rain in North America.
A connection that has already been demonstrated in several scientific studies and that a group of researchers from the University of Oregon have refocused: “Feedback loops amplify the need for climate action.” This is the title of their work published this Friday in the One Earth magazine and which identifies 27 global warming accelerators known as amplifying feedback loops and “that may not be taken into account in the climate fight,” they reveal.
Following COP21 in France, the leaders of major countries reached an agreement to limit global warming to well below 2, preferably 1.5 degrees Celsius, compared to pre-industrial levels. “Many countries have signed this pact,” say the authors of the research. Although, according to them, the action is incomplete because the view has been set on emissions and “one of the main factors that make climate change especially dangerous is the risk of amplifying climate feedback loops,” they highlight. “Climate models may be underestimating the acceleration in global temperature change.”
Infinite loop
In climate science, these loops are situations in which a disturbance caused by climate can trigger a process that causes further warming, which in turn intensifies the disturbance. An example is the warming of the Arctic that leads to the melting of sea ice, which, in turn, causes a further increase in temperatures because the reflectance of water is less than that of ice. “Some loops were discovered relatively recently,” the authors note.
In this work, doctors Chris Wolf, William Ripple and doctor Jillian Gregg expand this list to 41 feedback loops divided into biological and physical. The former include forest dieback, soil carbon loss, and forest fires; the physical ones involve changes such as reduced snow cover, increased Antarctic precipitation, and reduced Arctic sea ice.
The document makes two calls to action for “immediate and massive” emission reductions. The first focuses on minimizing short-term warming as “climate disasters” are already occurring in the form of wildfires, coastal flooding, permafrost thaw, intense storms, and other extreme weather events.
While the second puts the focus on mitigating potential major threats looming from climate tipping points “which are getting ever closer due to the prevalence of many amplifying feedback loops and we expect additional ones to be described in the near future.” , they point. “This may mean that the remaining carbon budget has been overestimated, in which case the proposed mitigation pathways are not valid and it is necessary to achieve net zero emissions faster than anticipated,” they warn.
The gap is currently 23 GtCO2e per year in 2030 to meet the 1.5ºC agreed in Paris. “It is declining very fast and perhaps waiting until 2050 to achieve net zero carbon emissions could be too late,” they add.
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