Climate change 'tipping points' too close for comfort
Category: Environment/Climate
Via: dignitatem-societatis • 5 years ago • 31 commentsBy: Marlowe Hood
S E E D E D C O N T E N T
Loading the atmosphere with five million tonnes of CO2 every hour has pushed Earth dangerously close to a no-return threshold, beyond which lies an unlivable hothouse world, top climate scientists have warned.
There are 15 known tipping points in the planet's complex climate system, and nine of them—including permafrost, the Amazon rainforest, the Greenland icesheet, Arctic sea ice, and the Atlantic Ocean's circulation—are alarmingly "on the move", they reported in the journal Nature.
Locked inside the tundra of Russia, Alaska and Canada, for example, is twice as much CO2 and methane as there is already in the atmosphere. If humanity cannot manage its own carbon pollution, what will we do if Earth turns from sink to source, adding even more?
AFP spoke to two of the authors—Tim Lenton, director of the Global Systems Institute at the University of Exeter, and Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research.
Losing control
Q. How has scientific understanding of tipping points changed over the last decade or two?
ROCKSTROM: Today we are reaching a point of unequivocal scientific evidence that these tipping elements are real. The Earth system is an interconnected, self-regulating bio-geophysical system that can exist in different stable states. You can have rainforests, such as in the Amazon, that can tip over and become savannah. You can have stable icesheets, or ice-free conditions.
We have come to realise that two degrees Celsius (3.6 degrees Fahrenheit) is not just a political temperature target, it is actually a planetary boundary. Go beyond that and we are at risk of unleashing self-reinforced warming—this is what Earth system scientists fear most.
The moment that the Earth system flips over from being self-cooling—which it still is—to self-warming, that is the moment when we lose control.
In 2001, the threshold was seen to be around 5C or 6C of warming. Today the IPCC estimate is between 2C and 3C. Coral reefs, Arctic sea ice and the West Antarctic icesheet have either crossed the tipping point already or are very close. You could call them the first planetary victims of Anthropogenic climate change.
Toppling dominoes
Q. Does that mean we need to shift our focus to preparing for the inevitable impacts that will follow?
LENTON: We will have to adapt to some changes that may now be unavoidable. The Amundsen Sea Embayment of West Antarctica might have passed a tipping point—the "grounding line" where ice, ocean and bedrock meet is retreating irreversibly.
When this sector collapses, it could destabilise the rest of the West Antarctic icesheet like toppling dominoes, leading to about three metres of sea-level rise on a timescale of centuries to millennia. Models suggest that the Greenland icesheet could be doomed at 1.5C of warming, which could happen as soon as 2030.
For long-term sea level rise, then, we should be looking seriously at relocation.
But what we know about tipping points should strengthen the argument for reducing greenhouse gas emissions. The fact that we start to see some unexpected shifts in the system should give an extra impetus to meet the Paris goals of limiting the warming as close to 1.5 as we can.
We've got a short-term challenge which is to try and get to net-zero greenhouse gas emissions in the next 30 years. That should be the focus of the most urgent attention. We need a joined-up strategy—it has to be a two-pronged approach.
Cascading impacts
Q. You highlight the ways in which different facets of Earth's climate system interact, and how that may amplify the risk of dire impacts.
ROCKSTROM: The cascading combinations are critically important, and pose a challenge to the scientific community. We see three in evidence today.
There is a connection, for example, between the Arctic and Antarctica via the ocean circulation system in the Atlantic. The slowdown in the so-called Atlantic overturning leads to more warm surface water in the Southern Ocean, which in turn leads to faster melting of the West Antarctic icesheet.
Changes in the Arctic and Greenland, meanwhile, can also help explain the more intense droughts in the Amazon basin, which result in more forest fires and pulses of CO2 into the atmosphere.
About 17 percent of the Amazon has been lost since 1970. Estimates of where an Amazon tipping point could lie range from 40 percent to just 20 percent of forest-cover loss. Finding the tipping point will require models that include the interaction of deforestation and climate change.
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What could possibly go wrong?
It is a worldwide conspiracy of misinformation and lies. It is impossible for human beings to damage our environment or even to trigger chain reactions that deliver the true payload. God would never let the planet be harmed.
It's sad that so many people seem to believe that, in part or in whole.
Environmental journalists and advocates have in recent weeks made a number of apocalyptic predictions about the impact of climate change. Bill McKibben suggested climate-driven fires in Australia had made koalas “functionally extinct.” Extinction Rebellion said “Billions will die” and “Life on Earth is dying.” Viceclaimed the “collapse of civilization may have already begun.”
Few have underscored the threat more than student climate activist Greta Thunberg and Green New Deal sponsor Rep. Alexandria Ocasio-Cortez. The lattersaid, “The world is going to end in 12 years if we don't address climate change.” Says Thunberg in her new book, “Around 2030 we will be in a position to set off an irreversible chain reaction beyond human control that will lead to the end of our civilization as we know it.”
Sometimes, scientists themselves make apocalyptic claims. “It’s difficult to see how we could accommodate a billion people or even half of that,” if Earth warms four degrees, said one earlier this year. “The potential for multi-breadbasket failure is increasing,” said another. If sea levels rise as much as the Intergovernmental Panel on Climate Change predicts, another scientist said, “It will be an unmanageable problem.”
Apocalyptic statements like these have real-world impacts. In September, a group of British psychologists saidchildren are increasingly suffering from anxiety from the frightening discourse around climate change. In October, an activist with Extinction Rebellion (”XR”) — an environmental group founded in 2018 to commit civil disobedience to draw awareness to the threat its founders and supporters say climate change poses to human existence — and a videographer, were kicked and beaten in a London Tube station by angry commuters. And last week, an XR co-founder said a genocide like the Holocaust was “happening again, on a far greater scale, and in plain sight” from climate change.
Climate change is an issue I care passionately about and have dedicated a significant portion of my life to addressing. I have been politically activeon the issue for over 20 years and have researched and written about it for 17 years. Over the last four years, my organization, Environmental Progress, has worked with some of the world’s leading climate scientists to prevent carbon emissions from rising. So far, we’ve helped prevent emissions increasing the equivalent of adding 24 million cars to the road.
I also care about getting the facts and science right and have in recent months corrected inaccurate and apocalyptic news media coverage of fires in the Amazon and fires in California, both of which have been improperly presented as resulting primarily from climate change.
Journalists and activists alike have an obligation to describe environmental problems honestly and accurately, even if they fear doing so will reduce their news value or salience with the public. There is good evidence that the catastrophist framing of climate change is self-defeating because it alienates and polarizes many people. And exaggerating climate change risks distracting us from other important issues including ones we might have more near-term control over.
I feel the need to say this up-front because I want the issues I’m about to raise to be taken seriously and not dismissed by those who label as “climate deniers” or “climate delayers” anyone who pushes back against exaggeration.
With that out of the way, let’s look whether the science supports what’s being said.
First, no credible scientific body has ever said climate change threatens the collapse of civilization much less the extinction of the human species. “‘Our children are going to die in the next 10 to 20 years.’ What’s the scientific basis for these claims?” BBC’s Andrew Neil askeda visibly uncomfortable XR spokesperson last month.
“These claims have been disputed, admittedly,” she said. “There are some scientists who are agreeing and some who are saying it’s not true. But the overall issue is that these deaths are going to happen.”
“But most scientists don’t agree with this,” said Neil. “I looked through IPCC reports and see no reference to billions of people going to die, or children in 20 years. How would they die?”....
It is maddening.
See @1.1.2 but note that this poster often claims that biochemical evolution is pseudoscience and is nothing but a worldwide conspiracy by godless scientists.
That's what happens when a religious mentality takes hold.
Forbes is a religious publication? Who knew?
I wasn't talking about Forbes.
earth has been much hotter in the past and much colder in the past several times over, the same thing will happen in the future. the idea that we can stabilize that? insane.
This has never been about human beings trying to control the greater climate of the planet. Yes, that is absurd. Climate science concerns have always been about effects that we do have control over that are triggering effects over which we have no control.
Here's a little something I thought was interesting:
Another video that could offer people a basic perspective but will be ignored.
Unfortunately, probably.
Stabilizing it? Not likely. Unless we really make some technological leaps. It's about the effect we have as a species and the means of how we can mitigate that effect to some degree.
like an ant pushing on a bowling ball. some effect, but to no avail.
have fun
But when a colony of ants works towards the same goal, then you see results.
find an ant hill then drop a bowling ball on it.
watch how long it takes for them to move it off their hill.
your gonna need a chair and a few ant lifetimes later you will find that ball did not move an inch due to their efforts
im not opposed to technology reducing carbon emissions but I am very against any proposed "global carbon tax"
just get the world to keep up with the usa in reducing co2 without making us pay for it.
cheers
Such a defeatist attitude.
nailed it. defeating globalists that is.
That is a meaningless argument. Yes, the environment has been radically different in the past, and will be in the future. Everyone knows that. Hell, in a few billion years the sun will literally destroy the planet. Over, finis, the end. That's not the point.
What matters is sustaining our fragile environment in the here and now, because this is the one that our civilization has evolved in, and the one that our children and grandchildren, and their children and grandchildren, will depend on for life. Not to mention all of the other marvelous species' on this planet.
The idea is that we need to stop destabilizing the natural climate so rapidly. We need to stop digging up massive amounts of carbon and burning it off into the air where it simply would not be without us. Either that, or we need to invest heavily in technologies that can sequester and store carbon byproducts as we make them, before they're released into the air. It may sound expensive, but doing nothing will be even more expensive in the long run, many times over.
That is unrealistic thinking. Alternative fuels, solar, wind, hydrogen, and geothermal cannot meet the world's energy requirements
Fossil fuels will be used far into the future because of availability and price. The US could reduce emissions by 75%, but the rest of the nations could not do that.
Who in the world told you that? I once saw a physicist demonstrate formulaically that solar alone is on par with nuclear power generation -- per unit of surface area, that is. His example was a 1 GW nuclear plant occupying about a square kilometer of land. At mid to lower U.S. latitudes, roughly the same amount of solar energy lands on roughly the same amount of land.
Again, that's just solar. Generating non-fossil fuel power isn't the problem. The problem is storage for use during non-generating hours. Battery technology keeps making advances, though, and once we have the problem licked we'll be set. Nobody would even notice a difference.
Solar is already cheaper. The reasons we still use fossil fuels are dependability in generating electricity at night or when the wind isn't blowing, and portability for vehicles (gasoline is relatively easy to handle, highly mobile, and power-packed). But, again, once the storage problem is solved, there will be no reason whatsoever not to dump fossil fuels completely. Sunlight and the wind are free. There'll be no fuel costs for producers, only equipment purchases and operational/maintenance costs.
Better still, as far as vehicles are concerned, electric motors only have a couple of moving parts. Basically just the bearings at either end of the rotor. That beats the hell out of internal combustion engines when it comes to maintenance and servicing. Wouldn't that be great?
Once the storage problem is solved it'll be cheaper than existing fossil fuel technologies. The fuel is free. They'll have no reason not to go green.