[ad_1]
The science behind Melting Arctic permafrost is, frankly, terrifying. As it melts, the mummified remains of animals are slowly emerging, offering us a glimpse into the ancient world, one that scientists believed would always remain hidden, locked away forever. These cubs, birds, and other wildlife are the proverbial canaries in the coal mine.
Now, a new study published Thursday in Scientific reports gives us even more cause for concern.
Jørgen Randers is one of the study’s authors and emeritus professor of climate strategy at BI Norwegian Business School.. He says Reverse that permafrost may not be melting, but may never freeze again.
“According to our ESCIMO system dynamics simulation model, humanity is beyond the point of no return when it comes to stopping the melting of permafrost using greenhouse gas cuts as a single tool,” says Randers.
In other words: reduce (or completely eliminate) greenhouse gas emissions now I will not do it stop melting permafrost in the future.
Instead, Randers explains, “it will continue to melt for the next 500 years, regardless of how quickly humanity reduces its greenhouse gas emissions.”
How we got here – To reach this dire conclusion, Randers and co-author Ulrich Goluke used a simulation model known as ESCIMO (a model of the Earth system of intermediate complexity) to observe the self-sustaining melting of permafrost. Goluke is an assistant professor at Business School Lausanne, Switzerland.
They look at two possible scenarios.
In the more likely of the two scenarios, they assume that humans will completely eliminate human-made greenhouse gas emissions by 2100. In this scenario, global temperatures peak around 2075 before falling by 75 years at 2 degrees Celsius above pre-industrial temperatures. Earth by 2150. That is in tune with other science on what would have such a drastic action on global warming.
The unexpected is all that happens after 2150. After 2150, the global temperature counterintuitively start to climb again, despite the fact that there is no new production of greenhouse gases.
In the second, highly unrealistic scenario, which posits that humanity abruptly cuts all greenhouse gases in 2020, the same initial decline pattern followed by global warming still occurs.
Essentially, we have missed the boat. Rather, to stop the permafrost melting now, the study claims that “all human-made emissions would have to be reduced to zero sometime between 1960 and 1970,” when global temperature was only 0.5 degrees Celsius above. from pre-industrial levels. .
Vicious circle – This strange oscillation in global temperature comes down to three factors: the melting of the permafrost itself, increased water vapor, and decreased surface albedo.
These three processes interact in a self-sustaining feedback loop, resulting in the release of more carbon (in the form of methane or CO2) into the atmosphere. More carbon increases global temperatures and further causes permafrost to melt.
Let’s focus on that last factor: superficial albedo.
“Surface albedo is the same as reflectivity, the brightness of the Earth’s surface as seen from space. Shiny surfaces like snow and ice reflect most of the incoming energy from the Sun,” Randers says.
In contrast, dark areas, such as the sea, are less reflected and instead absorb more energy.
“This means that as the globe warms, the area covered by ice and snow decreases, exposing more of the ocean surface, absorbing more incoming light, warming and melting even more surface ice,” Randers says.
This has extreme implications for humans for the next 200 years: Starting in 2150, the global temperature will continue to rise 0.5 degrees Celsius every century, according to Randers.
“The rise will be so slow that humanity will probably adapt,” Randers says, but cautions that we will also suffer more than if temperatures and sea levels did not rise.
What’s next for permafrost? Reducing greenhouse gases in the next fifty years is still important for the survival of our species, and our actions now influence temperature increases in the future. But we also need to innovate to get out.
“The world should accelerate its efforts to reduce greenhouse gas emissions and begin developing technologies for the large-scale removal of greenhouse gases from the atmosphere,” Randers says.
Removal of greenhouse gases may not save permafrost in the long term. But investing in other innovative technologies, like carbon capture, could go a long way, Randers suggests.
It is also worth bearing in mind that this is only one simulation, and other models can provide more fruitful information on how to prevent permafrost from melting.
“The next step, and the most urgent one, is for other model builders to investigate whether they see the same phenomenon (sustained permafrost melting) in their models,” says Randers. “Their models are much larger than ours and can reveal opposing forces that can stop the melting that we observe in ESCIMO.”
Summary: The risk of points of no return, which, once overcome, lock the world in a new dynamic, has been debated for decades. Recently, there have been warnings that some of these tipping points are approaching and too dangerous to ignore. In this document we report that in the ESCIMO climate model the world has already passed a point of no return for global warming. At ESCIMO we observe the self-sustaining melting of permafrost for hundreds of years, even if global society stops all man-made GHG emissions immediately. We encourage other model makers to explore our discovery on their (larger) models and report their findings. The melting (in ESCIMO) is the result of a continuous self-sustaining increase in global temperature. This warming is the combined effect of three physical processes: (1) decrease in surface albedo (driven by the melting of the Arctic ice sheet), (2) increase in the amount of water vapor in the atmosphere (driven by temperatures higher) and (3) changes in GHG concentrations in the atmosphere (driven by absorption of CO2 in biomass and oceans, and emission of carbon (CH4 and CO2) from melting permafrost). This self-sustaining melting process, in the sense that there are no more GHG emissions, (in ESCIMO) is a causally determined physical process that evolves over time. It begins with man-made warming up to the 1950s, leading to an increase in the amount of water vapor in the atmosphere, further raising the temperature, causing a greater release of carbon from the melting of the permafrost and, at the same time, a decrease in surface albedo as ice and snow melt. To stop self-sustaining warming in ESCIMO, huge amounts of CO2 must be removed from the atmosphere.
