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Editor’s note: News about conservation and the environment is made every day, but some of it can fly under the radar. In a recurring feature, Conservation News shares a recent news story that you should know about.
Global temperatures have risen by 1.2 degrees Celsius (2.2 degrees Fahrenheit) since the start of the second Industrial Revolution. There is a significant risk that without immediate reductions in greenhouse gas emissions, we could witness a rise above the crucial 1.5 degrees Celsius (2.7 degrees Fahrenheit) threshold within the next five years, with probabilities hovering around 50 percent.
A recent study indicates that the repercussions of surpassing these limits could be more severe than previously anticipated. The research reveals potential irreversible damage to fundamental Earth systems, as reported by Henry Fountain in The New York Times.
The study’s authors, led by Johan Rockström, chief scientist at Conservation International, evaluated the risks of 16 distinct climate “tipping points.” These are critical thresholds that, once crossed, could initiate a self-reinforcing cycle of environmental decline. The findings, published in Science, highlighted three tipping points likely to occur at 1.5 degrees Celsius (2.7 degrees Fahrenheit) of warming.
First, the vulnerability of massive ice sheets in Greenland and West Antarctica is pronounced. As these ice sheets melt, they lose both mass and altitude, which exposes them to warmer air and accelerates their disintegration. The loss of this ice could result in significant sea-level rise globally.
Secondly, Arctic permafrost is at risk of rapid thawing. This frozen terrain holds over 1,000 gigatons of carbon, which is roughly equivalent to a century’s worth of human emissions at current rates. The thawing process would release vast amounts of carbon into the atmosphere, further escalating global temperatures. Additionally, diminishing ice cover would increase solar radiation absorption by Arctic land, compounding the melting issue.
Thirdly, coral reefs—which are integral to the survival of 25% of marine species—face the threat of mass bleaching. Excessively warm waters cause corals to expel vital symbiotic microbes, leading to their mortality. The resulting decline in coral coverage could have dire consequences for marine ecosystems, threatening millions of people who rely on these systems for food, livelihoods, and protection from storms.
As temperatures rise to 2 degrees Celsius (3.6 degrees Fahrenheit), the authors noted an increase in risks, including the swift disappearance of mountain glaciers crucial for freshwater rivers and the potential collapse of deep-sea ecosystems in the North Atlantic that influence weather patterns across Europe. If these tipping points are activated, the consequences could be disastrous for climate, biodiversity, and human society. Some processes may already be beginning, according to the researchers.
Rockström emphasized the significance of every incremental rise in temperature, stating, “Every tenth of a degree counts,” in remarks to The New York Times.
In light of the Paris Agreement established in 2015, which aimed for global warming to remain well below 2 degrees Celsius (3.6 degrees Fahrenheit) and ideally under 1.5 degrees Celsius, the findings underscore the necessity of drastic action. Rockström noted that to meet these targets, fossil fuel emissions must be halved every decade. Currently, few nations are on schedule to meet these goals, with projections suggesting that current policies may lead to a net warming of 2.6 degrees Celsius (4.7 degrees Fahrenheit) by the end of the century.
This November, global leaders will convene in Egypt for the United Nations climate summit, COP27. Following a breakthrough in negotiations last year that established rules for international carbon trading, discussions are set to tackle the implementation of the Paris Agreement. However, experts predict that these negotiations will be complicated by ongoing energy crises, despite the increasingly apparent impacts of climate change.
Conservation International CEO M. Sanjayan remarked on the findings, stating, “This report by Johan Rockström and colleagues is a sobering reminder that +1.5 degrees Celsius is not a prescription, it is a threshold — the point at which the fabric of life starts to come apart at the seams. We cannot afford gridlock at COP27: It’s time to fully deliver on the Paris Agreement.”
Read the full article here.
Source
www.conservation.org