A new study published in Nature Sustainability found that ecosystem collapse will come sooner than previously thought. The researchers discovered how tipping points of nature "can amplify and accelerate one another." One-fifth of the earth's ecosystems, including Amazonia, are at risk of collapse within our lifetimes.
“It could happen very soon. We could realistically be the last generation to see the Amazon.” Prof Simon Willcock-Rothamsted ResearchScientists do not argue about science. They argue around the edges of science. And this is true about this study. One argument being used is the disturbing term “by 2100,” which, to me, is selfish and delusional. It buys the grandchildren nothing except for an inheritance of a dead and dying world. We blew it on climate change, but some, not all, ecosystems can repair themselves if we let them. Too many humans on Earth are devouring everything, and I don’t see us stopping the collapse in time.
The IPCC is designed for compromise and is more conservative than science dictates. They weighed in on the study.
The United Nations’ top science advisory body, the Intergovernmental Panel on Climate Change, has been more cautious. In its latest report, it said there was a chance of a tipping point in the Amazon by the year 2100.
However, several prominent Brazil-based scientists, including Carlos Nobre, have warned that this may come much sooner. The new study underlines that alarming prospect. It observes that most studies until now have focused on one driver of destruction, such as climate change or deforestation. But when you combine this with other threats, such as water stress, degradation and river pollution from mining, the breakdown comes much quicker.
Lake Erhai in China collapsed sooner than most observers expected. According to Willcock, this was because projections had been based on one factor – agricultural runoff that was loading the water system with excess nutrients – but other stresses compounded and accelerated this degradation. When climate variation, water management and other forms of pollution were added into the mix, the lake system quickly lost its resilience.
Overall, the team, comprised of scientists from Southampton, Sheffield and Bangor universities, as well as Rothamsted Research, looked at two lake ecosystems and two forests, using computer models with 70,000 adjustments of variables. They found that up to 15% of collapses occurred as a result of new stresses or extreme events, even while the primary stress was maintained at a constant level. The lesson they learned was that even if one part of an ecosystem is managed sustainably, new stresses such as global warming and extreme weather events could tip the balance towards a collapse.
The researchers concluded that policymakers need to act quickly and decisively. I couldn't agree more.