What Happens as the Earth Warms and Climate Adjusts

GR: Editors at Futurism.com researched global warming and produced the infographic below. The names of the editors appear near the end of the graphic. We are fortunate that Robert Scribbler reviewed the graphic’s projections. His remarks follow the graphic.

Robert Scribbler:

[In general:]  “A bit over the mark in some respects accurate in broad brush in others.

“1 C = present warming. Actually, we’re at 1.2 C now. We do have loaded dice for heatwaves capable of producing mass injury and mortality. So far, it appears that our heat readiness has increased as well. Damages to agriculture are on the rise. Threats to water supplies are also increasing. Severe weather is intensifying.

“1.5 C appears to be a threshold where we start to see some relatively considerable carbon store feedbacks — perhaps half a billion tons per year addition vs the 20th Century from the Earth System or about 4 percent of the present human emission. Maybe a bit more.

“2 C The statements for rates of sea level rise are tough to prove. That said, at 1.5 to 2.5 C there appears to be considerable risk of crossing various melt thresholds that produce multimeter sea level rise per Century. Extinction pressure from compounded factors including climate change makes the 1/3 number possible at 2 C. Climate pressure alone probably represents more than half of this. See:

https://www.theguardian.com/environment/2017/feb/25/half-all-species-extinct-end-century-vatican-conference

“It will be tough to avoid 2 C warming by the end of this Century if we do not rapidly cut fossil fuel burning as the article suggests. The 492 CO2e number concerns me quite a bit because it implies 2.1 to 2.3 C warming by the end of this Century. If we get to zero fossil fuel burning by 2040, that still implies about 520 CO2e which perhaps drops back to 480 or 490 as methane falls out. That’s still very close to the mark. It looks to me like we have to both perform that rapid cut and look at atmospheric carbon capture by various means. In any case, these very high CO2e levels are highly unsafe, in my view.

“Passing 2 C probably implies about 800 million to 1 billion tons per year of carbon feedback from the Earth System by end Century. That’s about 7-9 percent of the present human emission.

“I think in this range we hit a bit of a warming speed bump as glaciers start going down more rapidly and seas begin to really rise. As a result, you’re probably looking at a number of decades and possibly Centuries of very severe storm impacts and very unstable and difficult to predict weather. The ice sheets dumping into the oceans and harming AMOC and other ocean circulation patterns will also tend to disrupt regional and global weather. So it’s here that you get into a period of rapid ocean stratification and extraordinarily bad weather conditions.

“I know I’ve said that we are on a path to 4 C under typical warming scenarios, but I think we also need to hold out what happens if ice sheet response becomes quite large.

“3 C: Traditional agriculture is going to be taking very hard hits even leading up to 3 C. Post 3 C probably does represent an decline threshold. Adaptation will require very extensive indoor vertical farming on the order of requiring national policy initiatives to support their build-out. Carbon feedbacks do become a bit more of a problem as you start pushing at stores that were laid down more than 5 million years ago. The sea ice and salt water incursion scenarios are in the ballpark.

“4 C: You’re probably well past major thresholds for a several glacier systems. 50 meters of long term sea level rise is probably locked in at this point, although you don’t get all that SLR all at once. Cities at 118 F — well, we have cities out west that are predicted to hit 116 this week. So that’s not too far fetched at all.Wet bulb at 35 C becomes pretty common in a number of regions during hot periods at this threshold. Agricultural collapse pressure is very high. A number of regions including Europe, the U.S. West, China, large parts of Africa, India and many more are all likely to be well outside of growing temperature ranges at this time. Loss of 500 billion tons of carbon from the Arctic at 4 C over 500 years is probably possible at this time. Total annual carbon feedback is probably edging into a range of 1.5 billion tons per year from the Earth System.

“5 C: It’s probably enough to completely bring down both Greenland and Antarctic ice over a number of Centuries if warming stopped at 5 C — faster if you keep warming beyond it. Economic damages are certainly quite severe due to very long term crisis. You’re basically looking at a much poorer world where natural resources are much more constrained. Unless the human system produces wealth internally, poverty will be quite rampant. 5 C warming is about 4-7 C cooler than peak PETM warming. It’s worth noting that a lot of the damages will come from a high velocity rate of warming in this scenario in which natural systems would usually have thousands of years to adapt to changes that could occur within a Century or so. Without a collective response, competition over resources would become quite difficult and potentially very vicious.

“6 C: Peak Permian Extinction warming was about 14 C warmer than 1880s. 6 C is not comparable to worst case Permian levels. That said, the level of greenhouse gas emission (approx 1200 ppm CO2e implied) that would achieve 6 C warming at end Century could produce a Permian type extinction event over longer periods (many centuries).

“At 6 C you’re not quite yet in the range where you’re worried about full-on Canfield Ocean type effects. [GR:  Canfield Oceans produce deadly hydrogen sulfide. At the “full-on level, the gas rolls onshore and wipes out all animals and most (all?) plants.] However, you probably have regional dead zones that look a lot like a Canfield Ocean and are full of hydrogen sulfide producing bacteria. Sea creatures that enter these dead zones would mostly perish producing various ocean boneyards. I think at this point you probably have 50-60 percent of species threatened with extinction if this warming occurs very rapidly along a 1 Century to 150 year timescale. That said, if you achieve 6 C warming you are pushing at carbon stores that are 30 million years old or more. So you’ve probably set off a long term run up to a hyperthermal like the PETM or possibly the Permian if the carbon stores are deep enough and release long enough. In my opinion, you probably get something closer to the PETM if you peaked human fossil fuel based emissions to an 800 ppm CO2e level (implied 5 C warming at end Century and 10 C warming long term from the base forcing). If you keep burning fossil fuels, through end Century and achieve a base forcing of around 1,200 ppm CO2e or more (implied 6 C warming at end Century and 12 C warming long term from the base forcing) then what you get in the end may well resemble the Permian (or worse) due to combined human emission and Earth System feedbacks.” –Robert Scribbler.

Scribbler added this:  “So the Permian killed off 90 to 95 percent of all species in the ocean and about 75 percent of all species on land. The various killing mechanisms didn’t kill off all plant life. But the world was very barren, lifeless, and toxic compared to the rich bounty we enjoy today.

It’s worth noting that the hydrogen sulfide venting effect likely produced a number of killing mechanisms for land forms. Some would include direct poisoning. But venting into the upper atmosphere would have harmed the ozone layer which would have hit land forms very hard as well.

“I think the direct testament to the danger of sulfur related compounds like hydrogen sulfide have been deeply ingrained in land forms to this day. Even a small amount of sulfur is detectable by the noses of mammals — to produce a danger response. This is probably an evolutionary mechanism that came up from the dangers of hothouse times.” –Robert Scribbler.

We only have a 5 percent chance of avoiding ‘dangerous’ global warming

GR: Most journalists reporting on climate-change predictions are reluctant to emphasize worst-case scenarios. Popular climate scientists share this reluctance, claiming that discussing worst-case possibilities discourages rather than encourages disaster planning and preparation. However, we shouldn’t treat climate scientists’ worst-case descriptions as pessimism; we should treat them as warnings. Most climate scientists have become dubious that we can limit global warming to the goals set in the Paris Accord. So, what is a reasonable response? There’s a bit of ancient advice that you find scattered across the U. S. Federal Emergency Management Agency (FEMA) website:

“Hope for the best, but plan for the worst.”

Unfortunately, most people aren’t preparing for the worst. There is growing media attention to emergency planning, and in fact, many major corporations and most military divisions are preparing. In many countries, however, leaders are not telling people to prepare. In the U. S., many elected leaders are telling their constituents that climate change is a hoax. In case you missed this earlier post, here’s a reasonable pair of suggestions for governments and for citizens.

Chris Mooney.– “In recent years, it has become increasingly common to frame the climate change problem as a kind of countdown — each year we emit more carbon dioxide, narrowing the window for fixing the problem, but not quite closing it yet. After all, something could still change. Emissions could still start to plunge precipitously. Maybe next year.

“This outlook has allowed, at least for some, for the preservation of a form of climate optimism in which big changes, someday soon, will still make the difference. Christiana Figureres, the former head of the United Nations’ Framework Convention on Climate Change, recently joined with a group of climate scientists and policy wonks to state there are three years left to get emissions moving sharply downward. If, that is, we’re holding out hope of limiting the warming of the globe to below 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial temperatures, often cited as the threshold where “dangerous” warming begins (although in truth, that’s a matter of interpretation).

The projected global average temperature change by 2100 is 3.2 C (5.8 F), with a 90 percent chance it will fall within 2.0-4.9 C (3.6-8.8 F). (Adrian Raftery/University of Washington)

Yet a battery of recent studies call into question even that limited optimism. Last week, a group of climate researchers published research suggesting the climate has been warming for longer than we thought due to human influences — in essence, pushing the so-called “preindustrial” baseline for the planet’s warming backwards in time. The logic is clear: If the Earth has already warmed more than we thought due to human activities, then there’s even less remaining carbon dioxide that we can emit and still avoid 2 degrees of warming.” –Chris Mooney (Continue reading: We only have a 5 percent chance of avoiding ‘dangerous’ global warming, a study finds – The Washington Post.)

When Will Climate Change Make the Earth Too Hot For Humans?

GR: July 11, 2017:  I sometimes post rather dark doomsdayish items about climate change. It’s a reaction to the uncertain nature of science. However, the mays, mights, and possiblies, seem to promote procrastination. When used in climate-change warnings, they are exasperating to a two-stepper like me. In the article below, the author lays out the realities of climate change from the no-matter-what-we-do certainties to the worst-case possibilities (and he uses proper English).

David Wallace-Wells– “It is, I promise, worse than you think. If your anxiety about global warming is dominated by fears of sea-level rise, you are barely scratching the surface of what terrors are possible, even within the lifetime of a teenager today. And yet the swelling seas — and the cities they will drown — have so dominated the picture of global warming, and so overwhelmed our capacity for climate panic, that they have occluded our perception of other threats, many much closer at hand. Rising oceans are bad, in fact very bad; but fleeing the coastline will not be enough.

“Indeed, absent a significant adjustment to how billions of humans conduct their lives, parts of the Earth will likely become close to uninhabitable, and other parts horrifically inhospitable, as soon as the end of this century.

“Even when we train our eyes on climate change, we are unable to comprehend its scope. This past winter, a string of days 60 and 70 degrees warmer than normal baked the North Pole, melting the permafrost that encased Norway’s Svalbard seed vault — a global food bank nicknamed “Doomsday,” designed to ensure that our agriculture survives any catastrophe, and which appeared to have been flooded by climate change less than ten years after being built.

“The Doomsday vault is fine, for now: The structure has been secured and the seeds are safe. But treating the episode as a parable of impending flooding missed the more important news. Until recently, permafrost was not a major concern of climate scientists, because, as the name suggests, it was soil that stayed permanently frozen. But Arctic permafrost contains 1.8 trillion tons of carbon, more than twice as much as is currently suspended in the Earth’s atmosphere. When it thaws and is released, that carbon may evaporate as methane, which is 34 times as powerful a greenhouse-gas warming blanket as carbon dioxide when judged on the timescale of a century; when judged on the timescale of two decades, it is 86 times as powerful. In other words, we have, trapped in Arctic permafrost, twice as much carbon as is currently wrecking the atmosphere of the planet, all of it scheduled to be released at a date that keeps getting moved up, partially in the form of a gas that multiplies its warming power 86 times over.

“Maybe you know that already — there are alarming stories every day, like last month’s satellite data showing the globe warming, since 1998, more than twice as fast as scientists had thought. Or the news from Antarctica this past May, when a crack in an ice shelf grew 11 miles in six days, then kept going; the break now has just three miles to go — by the time you read this, it may already have met the open water, where it will drop into the sea one of the biggest icebergs ever, a process known poetically as “calving.”

“But no matter how well-informed you are, you are surely not alarmed enough. Over the past decades, our culture has gone apocalyptic with zombie movies and Mad Max dystopias, perhaps the collective result of displaced climate anxiety, and yet when it comes to contemplating real-world warming dangers, we suffer from an incredible failure of imagination. The reasons for that are many: the timid language of scientific probabilities, which the climatologist James Hansen once called “scientific reticence” in a paper chastising scientists for editing their own observations so conscientiously that they failed to communicate how dire the threat really was; the fact that the country is dominated by a group of technocrats who believe any problem can be solved and an opposing culture that doesn’t even see warming as a problem worth addressing; the way that climate denialism has made scientists even more cautious in offering speculative warnings; the simple speed of change and, also, its slowness, such that we are only seeing effects now of warming from decades past; our uncertainty about uncertainty, which the climate writer Naomi Oreskes in particular has suggested stops us from preparing as though anything worse than a median outcome were even possible; the way we assume climate change will hit hardest elsewhere, not everywhere; the smallness (two degrees) and largeness (1.8 trillion tons) and abstractness (400 parts per million) of the numbers; the discomfort of considering a problem that is very difficult, if not impossible, to solve; the altogether incomprehensible scale of that problem, which amounts to the prospect of our own annihilation; simple fear. But aversion arising from fear is a form of denial, too.

“In between scientific reticence and science fiction is science itself. This article is the result of dozens of interviews and exchanges with climatologists and researchers in related fields and reflects hundreds of scientific papers on the subject of climate change. What follows is not a series of predictions of what will happen — that will be determined in large part by the much-less-certain science of human response.” (Continue reading: When Will Climate Change Make the Earth Too Hot For Humans?)