Earth outside ‘safe operating space’ for humanity, says new study. Are we in danger?

A new study says Earth is now outside its ‘safe operating space’ for humanity. The study was published by international scientists in the journal Science Advances on Wednesday. “We are in very bad shape,” said study co-author Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research in Germany. “We show in this analysis that the planet is losing resilience and the patient is sick.” But what does this mean exactly?  Let’s take a closer look: What happened? According to CNN, 29 scientists in eight nations examined nine “planetary” boundaries the planet needs to remain within for humanity to have a liveable home. These boundaries, first created in 2009, include several key indicators of our planet’s health such as climate change, biodiversity, freshwater and land use, and the impact of synthetic chemicals and aerosols. Rockstrom, a climate scientist, said these boundaries “determine the fate of the planet” and have been “scientifically well established” by numerous outside studies. As per Newsweek, the nine boundaries are:

• Climate change
• Biosphere integrity
• Land system change
• Freshwater usage
• Biogeochemical flows
• Novel entities (the percentage of synthetic chemicals released into the environment)
• Stratospheric ozone depletion
• Atmospheric aerosol loading
• Ocean acidification

In most of the cases, the team uses other peer-reviewed science to create measurable thresholds for a safety boundary. For example, they use 350 parts per million of carbon dioxide in the air, instead of the Paris climate agreement’s 1.5 degrees (2.7 degrees Fahrenheit) of warming since pre-industrial times. This year carbon in the air peaked at 424 parts per million. What did the study find? As per The Guardian, the study found that human behaviour has caused six of these “planetary boundaries” to be breached.

Worse, two other boundaries – air pollution and ocean acidification – are on the brink of being crossed.

Scientists said that perhaps the most worrying find is that the four biological boundaries are at their highest level of risk. Biodiversity – the amount and different types of species of life – is in some of the most troubling shape and it doesn’t get as much attention as other issues, like climate change, Rockstrom said. [caption id=“attachment_13123292” align=“alignnone” width=“640”] The nine factors are intermingled. When the team used computer simulations, they found that making one factor worse, like the climate or biodiversity, made other Earth environmental issues degrade, while fixing one helped others. AP[/caption] “Biodiversity is fundamental to keeping the carbon cycle and the water cycle intact,” Rockstrom said. “The biggest headache we have today is the climate crisis and biodiversity crisis.” Water went from barely safe to the out-of-bounds category because of worsening river run-off and better measurements and understanding of the problem, Rockstrom said. If Earth can manage these nine factors, Earth could be relatively safe. But it’s not, he added. The nine factors are intermingled. When the team used computer simulations, they found that making one factor worse, like the climate or biodiversity, made other Earth environmental issues degrade, while fixing one helped others. Rockstrom said this was like a simulated stress test for the planet. The simulations showed “that one of the most powerful means that humanity has at its disposal to combat climate change” is cleaning up its land and saving forests, the study said. Returning forests to late 20th Century levels would provide substantial natural sinks to store carbon dioxide instead of the air, where it traps heat, the study said. However, there is some good news. The ozone is not under threat after human beings phased out certain chemicals  in recent years and the hole in the atmosphere decreased, as per The Guardian. What does this mean? Experts say this is a bad sign for humanity. Katherine Richardson, the lead scientist of the study, warned Newsweek, “We humans—just like all other living organisms—survive by using the Earth’s resources but those resources are limited.” Richardson, a professor of biological oceanography at the University of Copenhagen’s Globe Institute, added, “We can think of the Earth’s resources as the currency that supports us. The planetary boundaries framework is like a bank statement. It tells us how much of various components, or resources, of the Earth system we can allow ourselves to use without greatly increasing the risk that our activities will lead to dramatic and potentially irreversible changes in overall environmental conditions.” [caption id=“attachment_13101062” align=“alignnone” width=“640”] Glaciers are melting quickly due to rapid climate change. AP[/caption] Carnegie Mellon environmental engineering professor Granger Morgan, who wasn’t part of the study, said, “Experts don’t agree on exactly where the limits are, or how much the planet’s different systems may interact, but we are getting dangerously close.” “I’ve often said if we don’t quickly cut back on how we are stressing the Earth, we’re toast,” Morgan added. “This paper says it’s more likely that we’re burnt toast.”  ‘Make no sense’ Some, however, are skeptical of the doom and gloom. Carnegie Mellon chemistry and environment professor Neil Donahue said the fact that ozone layer is the sole improving factor shows that when the world and its leaders decide to recognize and act on a problem, it can be fixed. “For the most part there are things that we know how to do” to improve the remaining problems, Donahue added. Speaking to CNN, Oxford University physics professor Raymond Pierrehumbert allowed that ‘planetary boundaries’ can be useful in certain categories like carbon pollution. However, he added that when it comes to other measurements like land use change “it can be a distraction to argue over where to put the boundary and whether or not it has been ‘exceeded’” Stuart Pimm, the Doris Duke chair of conservation ecology at Duke University, told the outlet, “The measures they use make no sense and they cannot estimate them.” Pimm in 2018 co-wrote a paper on planetary boundaries and has long-disputed Rockstrom’s methods and measurements, saying it makes the results not worth much. University of Michigan environmental studies dean Jonathan Overpeck, who wasn’t part of the study, struck a more balanced note.

He called the study “deeply troubling in its implications for the planet and people should be worried.”

“The analysis is balanced in that it clearly sounds a flashing red alarm, but it is not overly alarmist,” Overpeck added. “Importantly, there is hope.”  With inputs from agencies