Category Archives: Climate Change

A key part of Antarctica is doomed to slow collapse

No matter how much the world cuts back on carbon emissions, a key and sizable chunk of Antarctica is essentially doomed to an “unavoidable” melt, a new study finds.

Associated Press, by Seth Borenstein, AP video produced by Teresa de Miguel, October 23, 2023

No matter how much the world cuts back on carbon emissions, a key and sizable chunk of Antarctica is essentially doomed to an “unavoidable” melt, a new study found.

Though the full melt will take hundreds of years, slowly adding nearly 6 feet (1.8 meters) to sea levels, it will be enough to reshape where and how people live in the future, the study’s lead author said.

Researchers used computer simulations to calculate future melting of protective ice shelves jutting over Antarctica’s Amundsen Sea in western Antarctica. The study in Monday’s journal Nature Climate Change found even if future warming was limited to just a few tenths of a degree more – an international goal that many scientists say is unlikely to be met – it would have “limited power to prevent ocean warming that could lead to the collapse of the West Antarctic Ice Sheet.”

“Our main question here was: How much control do we still have over ice shelf melting? How much melting can still be prevented by reducing emissions?” said study lead author Kaitlin Naughten, an oceanographer at the British Antarctic Survey. “Unfortunately, it’s not great news. Our simulations suggest that we are now committed to the rapid increase in the rate of ocean warming and ice shelf melting over the rest of the century.”

While past studies have talked about how dire the situation is, Naughten was the first to use computer simulations to study the key melting component of warm water melting ice from below, and the work looked at four different scenarios for how much carbon dioxide the world pumps into the atmosphere. In each case, ocean warming was just too much for this section of the ice sheet to survive, the study found.

Naughten looked at melting gatekeeper ice shelves, which float over the ocean in this area of Antarctica that is already below sea level. Once these ice shelves melt, there’s nothing to stop the glaciers behind them from flowing into the sea.

Naughten specifically looked at what would happen if somehow future warming was limited to 1.5 degrees Celsius (2.7 degrees Fahrenheit) over mid-19th century levels — the international goal — and found the runaway melting process anyway. The world has already warmed about 1.2 degrees Celsius (nearly 2.2 degrees Fahrenheit) since pre-industrial times and much of this summer temporarily shot past the 1.5 mark.

This undated image provided by British Antarctic Survey, shows the North Cove, in Antarctic. (Michael Shortt/British Antarctic Survey via AP)

Naughten’s study concentrated on the part of the West Antarctic Ice Sheet that is most at risk from melting from below, near the Amundsen Sea. It includes the massive Thwaites ice shelf that is melting so fast it got the nickname “the Doomsday Glacier.” West Antarctica is only one-tenth of the southern continent but is more unstable than the larger eastern side.

That part of Antarctica “is doomed,” said University of California Irvine ice scientist Eric Rignot, who wasn’t part of the study. “The damage has already been done.”

University of Colorado ice scientist Ted Scambos, who also wasn’t part of the study, said this ice sheet “eventually is going to collapse. It’s not a happy conclusion and it is one that I’m only saying reluctantly.”

Naughten doesn’t like to use the word “doomed,” because she said 100 years from now the world might not just stop but reverse carbon levels in the air and global warming. But she said what’s happening now on the ground is a slow collapse that can’t be stopped, at least not in this century.

“I think it’s unavoidable that some of this area is lost. It’s unavoidable that the problem gets worse,” Naughten told The Associated Press. “It isn’t unavoidable that we lose all of it because sea level rise happens over the very long term. I only looked in this study up to 2100. So after 2100, we probably have some control still.’’

No matter what words are used, Naughten said she and other scientists studying the area in previous research conclude that this part of Antarctica “couldn’t be saved or a lot of it couldn’t be saved.”

Naughten’s study did not calculate how much ice would be lost, how much sea level would rise and at what speed. But she estimated that the amount of ice in the area most at risk if it all melted would raise sea levels by about 1.8 meters (5.9 feet).

This 2020 photo provided by the British Antarctic Survey shows the Thwaites glacier in Antarctica. (David Vaughan/British Antarctic Survey via AP)

However, she said, that is a slow process that would play out through the next few hundred years through the 2300s, 2400s and 2500s.

Naughten said that may seem like a long way away, but noted that if the Victorians of the 1800s had done something to drastically change the shape of our world, we would not look well on them.

This type of sea level rise would be “absolutely devastating” if it happened over 200 years, but if it could be stretched out over 2,000 years, humanity could adapt, Naughten said.

“Coastal communities will either have to build around or be abandoned,” Naughten said.

While this part of Antarctica’s ice sheet is destined to be lost, other vulnerable sections of Earth’s environment can still be saved by reducing heat-trapping emissions so there is reason to still cut back on carbon pollution, Naughten said.

Twila Moon, deputy chief scientist at the National Snow and Ice Data Center who wasn’t part of the research, said she worries that most people will see nothing but doom and gloom in the research.

“I don’t see a lot of hope,” Naughten said. “But it’s what the science tells me. So that’s what I have to communicate to the world.”

Naughten quoted former NASA scientist Kate Marvel, saying “when it comes to climate change we need courage and not hope. Courage is the resolve to do well without the assurance of a happy ending.”


The Climate Overshoot Commission Releases Its Report, Pts. 2 & 3

[Note from BenIndy Contributor Nathalie Christian: This is a long read, but a good one. After the first installment of Ted Parson’s three-part series introduced climate overshoot as a concept and offered a quick history of the Climate Overshoot Commission, these two follow-up parts explain just what is so interesting – and potentially so radical– in the Commission’s recently released report. As someone who studied the Montreal Protocol (briefly), I always wondered what was so different about the rules, systems, and concepts our global society deployed to reduce ozone-destroying CFCs (et al.) and the rules, systems, and concepts we are using now in our fight against the fossil fuels–induced climate crisis. “Money! Dump-trucks of money!” is of course the most obvious answer to any and all questions, but there’s more potential overlap for success that awaits you in this fascinating two-part finish to Parson’s analysis. I have emphasized key lines through this post to assist fellow skimmers, and marked when I have done so, but I hope many of you read the whole thing.]

Pt. 2, A Radical Proposal Hidden in Plain Sight in the Overshoot Commission Report

Click the image to read the full report on the Climate Overshoot website.

The Commission’s recommendations on emissions include a fossil phaseout much stronger than anything now proposed, which could materially advance climate action.

Legal Planet, by Ted Parson, September 21, 2023

Edward A. (Ted) Parson is Dan and Rae Emmett Professor of Environmental Law and Faculty Co-Director of the Emmett Institute on Climate Change and the Environment at the University of California, Los Angeles.

Continuing my discussion of the report of the Climate Overshoot Commission released last week, today I dig into their recommendations on mitigation. As you may recall, the Commission’s informal (but serious) job description was to speak of elephants in the room and unclothed emperors: to say things that are true and important about climate risks and responses that other, more political constrained bodies cannot. If you take this job description for statements and apply it to recommendations, it would suggest recommending things that are not politically feasible – at least not now – or that even lie outside the range of current debate. This does not mean making recommendations so outlandish or implausible that they can readily be ignored or arbitrarily rejected, of course. But if the job is to move the range of acceptable arguments and proposals – moving the Overton window, as the political scientists say – the most effective recommendations may well lie beyond the boundary of what could be adopted now. This perspective is especially relevant to the Commission’s recommendations on mitigation.

Mitigation – deep rapid cuts to worldwide emissions – is the first, essential element of effective climate response. I don’t think there’s anyone thinking seriously about climate change who disagrees with this. In the Commission’s words, mitigation is the “foundational strategy.” Yet when the Commission began its work, it first planned not to speak about mitigation – not because they didn’t recognize its primary importance, but because they thought there wasn’t much for them to add to what’s already being said, particularly given the tight time limit on their work. But partway through, the Commissioners realized that not speaking on mitigation would risk them being mistakenly seen to not accord it the needed priority, so they changed course – correctly, even necessarily, in my view. But in making this decision, they also resolved that their messages on mitigation had to cut through the noise and move the debate, and thus sought to make their recommendations radical. I think they succeeded at this, although it’s not clear from the initial reactions to their report that their radicalism has been noticed – yet.

Their mitigation recommendations include calls to adopt stronger national and international accountability mechanisms for emissions cuts; policy and financing innovations to promote faster deployment of zero-emissions technologies; and for countries to recognize each other’s climate policies and reflect them in trade measures. They also call for cutting short-lived climate forcers even faster than now being pursued. These are strong recommendations, persuasive and well conceived. But they also could plausibly be adopted within a few years if governments are serious about ramping up their ambition, so do not necessarily meet the aim of proposing something radical enough to move the debate.

So, where’s the radicalism?

It’s in their very first mitigation recommendation, for a “graduated, differentiated phaseout” in production and consumption of fossil fuels. Wait a second, you might say, what’s so radical about that? Isn’t it obvious that the world needs to get rid of fossil fuels, and haven’t a bunch of people called for it? Well, yes. But the Commission’s proposal is vastly stronger than either the weak language adopted at Glasgow – which calls on parties to “… accelerat(e) efforts towards the phasedown of unabated coal power and phase-out of inefficient fossil fuel subsidies …” or the language now being discussed for the coming COP28, which speaks of phasing out unabated fossil fuels. The word “unabated” has been used frequently in recent months by Sultan al-Jaber of the United Arab Emirates who is overseeing this year’s COP; it was included in a draft document by EU countries; and it appears in the mitigation findings of the global stocktake released earlier this month. The Commission’s proposal is also substantially stronger, and at the same time more practical, than the most ambitious fossil-fuel proposals being promoted by activist nations: the Fossil Fuel Non-Proliferation Treaty and the Beyond Oil and Gas Alliance.

What makes the Commission’s proposal so radical is the combination of its ambition; its inclusion of key design elements that make it plausibly operationalizable; and the stature of the Commission. No mitigation proposal remotely this strong has been advanced in policy debate, certainly not by any body with stature similar to the Commission’s.

It is these elements taken together that make the Commission’s proposal radical.

Continue reading The Climate Overshoot Commission Releases Its Report, Pts. 2 & 3

Newsom’s Inaction Puts California Legislation Requiring Companies to Pay for Oil and Gas Well Cleanup in Limbo

[Note from BenIndy: Please take a minute to tell Governor Newsom to sign AB 1167. Here is his phone number:  (916) 445-2841, and here is a phone script, provided by 350 Bay Area Action: 

Phone script:  Hello, my name is ____________.  I live in ____________,  California and I’m a climate supporter of 350 Bay Area Action.  I am calling to ask the Governor to sign AB 1167, the bill requiring adequate bonding for plugging oil wells.  I want our state to do everything we can to protect the health of impacted communities and address the climate emergency.

Click this image to go to the governor’s contact form page. You will be redirected to a new site.

Prefer activism by email? You can urge Gov. Newsom to sign AB 1167 using his contact web form (clicking these links will redirect you to his contact page). There will be a drop-down menu where you can select the topic as “An Active Bill” and then another drop-down menu where you can select “AB 1167.” Follow the instructions to write a message. Please also note that our elected state representatives, Senator Bill Dodd and Assemblymember Lori Wilson, neglected to vote on this important bill.]

 

“A Setup for Disaster”: California Legislation Requiring Companies to Pay for Oil and Gas Well Cleanup in Limbo

An oil rig silhouetted by a golden sunset.
The bill, which awaits a decision by Gov. Gavin Newsom, follows ProPublica’s reporting on the multibillion-dollar cost to clean up California’s oil and gas industry and the exodus of major companies shifting ownership of thousands of aging wells. | Uncredited image.

ProPublica, by Mark Olalde, October 4, 2023

The California Legislature recently passed a bill that would provide the state’s taxpayers some of the strongest protections in the nation against having to pay for the cleanup of orphaned oil and gas wells. But Gov. Gavin Newsom has not indicated if he will sign it.

AB1167 would require companies that purchase idle or low-producing wells — those at high risk of being left to the state — to set aside enough money to cover the entire cost of cleanup. Assemblymember Wendy Carrillo, a Los Angeles Democrat who authored the bill with the support of the Natural Resources Defense Council and Environment California, said it’s needed to “stem the tide” of orphaned wells.

Newsom has until Oct. 14 to make a decision. A spokesperson declined to comment, saying the governor would evaluate the bill “on its merits.” The state’s Department of Finance released a two-page analysis opposing it.

It costs more than $180,000 to clean up an average orphan well in California, the state told the U.S. Department of the Interior in 2021, according to documents ProPublica obtained via a public records request. This includes plugging the well with cement, removing aboveground infrastructure like pumpjacks and decontaminating the site. But bonds, which are financial instruments guaranteeing to pay for cleanup, cover only a tiny fraction of that cost. A ProPublica analysis of state data found that oil and gas companies have set aside only about $2,400 per well. (State oil regulators are currently reevaluating companies’ bonds to increase them within existing law, which does not mandate that they cover the entire cleanup cost.)

Left unplugged, many wells leak climate-warming methane, brine and toxins that were used in the drilling process.

Newsom has until Oct. 14 to make a decision.  | Uncredited image.

“It’s a setup for disaster,” said Ann Alexander, a Natural Resources Defense Council senior attorney.

The bill follows ProPublica’s reporting on the exodus of oil majors from the state’s declining industry — one sale last year saw more than 23,000 wells move from Shell and ExxonMobil to a little-known German asset management group called IKAV — and on the multibillion-dollar cost to clean up the industry. ProPublica’s work was repeatedly cited by the Legislature and the bill’s supporters.

Despite its green reputation, California has a long history of weak oversight of its oil and gas industry, which has left behind an estimated 5,300 orphaned wells. Many are scattered across Los Angeles, complicating redevelopment. Others spew methane in Kern County’s huge oilfields.

Companies have little incentive to plug wells; it’s cheaper to sell or to walk away and forfeit the small bonds currently required by the state.

“It’s too easy for them right now to offload those unproductive oil wells to newer or less-resourced companies that may turn around and go bankrupt and that don’t have the adequate financial capacity to do the job of cleaning up,” said Laura Deehan, director of Environment California.

The Western States Petroleum Association and California Independent Petroleum Association industry trade groups warned state lawmakers that “this misguided bill will increase the number of orphan oil wells in California.” The organizations argued that requiring bonds that cover the full cleanup cost would dissuade sales to companies hoping to enter the market. This, in turn, could lead to well owners getting stuck with the expensive cleanup, causing insolvency and ultimately leaving the wells with the state.

Dwayne Purvis is a petroleum reservoir engineer who authored a study that estimated it would cost as much as $21.5 billion to clean up California’s oil industry. He pointed out that the most common type of bond — a surety policy — is similar to insurance guaranteeing a well will be plugged, so oil companies wouldn’t have to set aside the full cleanup cost in cash to comply with AB1167. Federal regulators recently found these bonds are relatively cheap.

If that stops companies from buying wells in California, Purvis said, then there’s a bigger problem: “This admits — implicitly but almost inescapably — that the cost of plugging exceeds the value of remaining production,” he told ProPublica via email.

A Western States Petroleum Association spokesperson did not address questions about its claims. The California Independent Petroleum Association did not respond to requests for comment.

In negotiations over the bill, according to people present, the trade associations pointed to one example in particular to highlight why the legislation would create more orphan wells — the sales of some of the more than 750 wells orphaned following bankruptcy filings by multiple entities in the Greka group of companies. The sales, the industry argued, presented an opportunity for the wells to be plugged by an oil company, not the state.

However, hundreds of the wells remain on the orphaned list to this day, only they’re now associated with a new company: Team Operating.

Greka’s CEO and Team Operating didn’t respond to emails requesting comment.

The bill does carry a potential loophole, experts cautioned: whether the increased bond requirements in the bill would apply to wells transferred through shell companies, as is often the case.

The state Department of Finance’s opposition to the bill relied on three arguments.

The agency’s report claimed that large companies with enough resources to plug wells are coming into the California market. But research shows these producers are exiting the state and handing off their aging, unprofitable wells to smaller companies that are less likely to be able to afford cleanup.

Its analysis also suggested that bond underwriting companies are “becoming hesitant” to do business in California. Purvis said that if these companies believe the situation is too risky to guarantee cleanup costs will be paid, “then the taxpayers of California probably should not extend producers the same credit.”

Finally, the report argued the bill is unnecessary because California regulators already have the authority to recoup plugging costs from wells’ previous owners.

While existing law gives the state this authority, it only applies to wells transferred after Jan. 1, 1996. Oil drilling in California dates back to the 1860s, and many thousands of wells were sold prior to the law’s cutoff, meaning the state can’t go after the wells’ former operators.

ProPublica reviewed the state’s list of orphaned wells and found numerous examples of well cleanups being left to taxpayers despite the wells being sold after 1996. In those cases, the state either hasn’t used its authority or has otherwise failed to secure plugging funds.

Department of Finance analysts referred questions to the state’s oil regulators, who were the source for much of the report. A spokesperson for the California Geologic Energy Management Division said state regulators have obtained money from previous owners on occasion.

But going after older operators is difficult, said Rob Schuwerk, a former New York assistant attorney general and the North American executive director of the energy finance think tank Carbon Tracker Initiative, and bonds are guaranteed money.

“There’s no better substitute for having the cash,” he said.

ProPublica is a Pulitzer Prize-winning investigative newsroom. Sign up for The Big Story newsletter to receive stories like this one in your inbox.

The Climate Overshoot Commission Releases Its Report

[Note from BenIndy: This first installment of an analysis of The Climate Overshoot Commission’s report is a bit weedy but worth your time. The report itself kicks off by stating that the likelihood of global warming exceeding the Paris Agreement’s goal of 1.5°C is “alarmingly high and continues to rise” before charging policymakers to reduce emissions, such as by an “ambitious and orderly phasing out of fossil fuels […] . ” Here, Dr. Parson of UCLA’s Emmett Institute on Climate Change and the Environment offers a brief history of the commission and what the high risk of exceeding the Paris Agreement’s goal – and “climate overshoot” – may mean for climate response.]

A dozen global leaders weigh in on the risk of exceeding the Paris temperature targets and what it means for climate response.

Click the image to read the full report on the Climate Overshoot website.

Legal Planet, by Ted Parson, September 18, 2023

Edward A. (Ted) Parson is Dan and Rae Emmett Professor of Environmental Law and Faculty Co-Director of the Emmett Institute on Climate Change and the Environment at the University of California, Los Angeles.

The Climate Overshoot Commission recently completed its work, releasing its report at the United Nations last Thursday, September 14. This report comes in conjunction with the U.N. General Assembly and a collection of high-level climate and environment events, including the Sustainable Development Goals Summit, 18-19 Sept, and the Climate Ambition Summit, 20 Sept.

The Climate Overshoot Commission is a senior independent international body, consisting of twelve distinguished individuals from around the world, including former heads of government, national ministers, and leaders of major environment, development, and civil society organizations. Chaired by Pascal Lamy, former Director-General of the World Trade Organization, it was convened by the Paris Peace Forum. The UCLA Emmett Institute contributed to the establishment and work of the Commission in several ways. Two former Emmett Institute law fellows served on the Secretariat. UCLA law students provided research and analytic support to the Secretariat in the International Climate Law and Policy Clinic. I served as a senior advisor to the Secretariat. In this and a few subsequent posts, I’ll present highlights of the Commission’s contributions, with some commentary — my own views, of course, not those of the Commission, which has very cogently spoken for itself.

There have been dozens of international commissions. Some of you may recall the 1986 World Commission on Environment and Development, or Brundtland Commission, which first popularized the idea of “sustainable development.” Commissions generally aim to advance international debate on hard issues, typically when other bodies are constrained in their ability to do so. Commissioners bring experience, stature, broad global representation—but crucially, are not presently in political office, so they are not required to advance national positions. They can speak and discuss freely. Like its predecessors, the job of the Overshoot Commission was to say things that are true and important, but that other more politically constrained bodies are unable to say: to talk loudly about elephants in the room and naked emperors.

This boiled down to two jobs. The first was to sound the alarm about the imminent likelihood of global heating exceeding the Paris temperature targets. The second was to say what this high risk of exceeding the targets— “overshoot”— means for climate response.

For the first, the Commission did its job pretty well, albeit with some reservations. Its forceful opening message is that the likelihood of global-average heating exceeding 1.5°C above pre-industrial levels—the more ambitious of the Paris targets—is “alarmingly high and continues to rise.” This is a stronger statement of this risk than has been made by any similarly high-level climate body, although not nearly as strong as is justified. Exceeding 1.5°C is virtually certain: indeed, it’s quite likely to happen within the next decade. More seriously, the Commission was silent on the risk of exceeding the higher Paris target, 2.0°C—with much more severe impacts than 1.5°C— which is also high and mounting. The Commission did report recent assessments from three bodies—the IPCC, UNEP, and IEA —which have synthesized projections of end-of-century heating. These are pretty alarming. Just maintaining present emissions-cutting actions—i.e., no further strengthening, but also no backsliding—give end-of-century heating of 3.2°C (IPCC), 2.6°C (UNEP), and 2.5°C (IEA); adding commitments in NDCs on top of current actions gets these down to 2.8°C (IPCC) or 2.4°C (UNEP); and adding conditional commitments and long-term net-zero targets reduces these to 1.7°C (UNEP and IEA). Getting better, but not very comforting.

Deciding how to speak effectively about such projections is surprisingly hard, for a couple of reasons. First, such statements aren’t just scientific but are also political—intended to report what is known or knowable about a risk, in such a way as to elicit a certain kind of response. All public-facing bodies like the Commission fret over how to sound the alarm that bad things are coming, to convey an appropriate level of action-motivating alarm without inducing despair and passivity. Second, there is real uncertainty in such statements, which gets larger and is more dependent on human choice the further ahead you look. While exceeding 1.5°C is pretty much locked in, there is so much range for human action in longer-term projections like 2.0°C, that most bodies —like the three the Commission quoted—speak not in terms of likelihood, but in terms of if-then, conditional statements. If control measures are this strong, then we project this degree of heating. The Commission chose to focus on the 1.5°C target, to speak very forcefully about the likelihood of exceeding it, but not to suggest certainty or unavoidability.

To give the Commission credit where due—and it is due in many places—on one point closely related to these projections, they were uncommonly and admirably frank: Noting the risks and the stark tradeoffs posed by aerosol pollution in the lower atmosphere. This pollution, mostly from burning fossil fuels that contain sulfur, has severe current environmental and health effects, estimated to kill more than 5 million people per year due to respiratory illness. It is also exerting an inadvertent cooling effect that masks a large fraction—perhaps a third to a half—of the climate forcing from previously emitted greenhouse gases that are already in the atmosphere. This pollution has to be cleaned up—and is being cleaned up—notably via the recently enacted tightening of restrictions on the sulfur content of marine bunker fuels adopted by the IMO. But cleaning this up will remove its cooling effect, which the IPCC recently estimated as 0.7°C.

Another related contribution the Commission made to climate clarity and realism (although less than it perhaps might have) concerns the use of the term for which it was named, “Climate Overshoot.”

Overshoot scenarios initially appeared in integrated assessment models (IAMs). They are projections in which some measure of environmental disruption initially exceeds a target, e.g., one of the Paris global temperature targets, but then stops growing, reverses, and eventually returns to the target level after this temporary period of exceedance. Calling these “overshoot scenarios” makes sense in describing model results, but is somewhat misleading in the real world, because it implies that once you exceed a target you are on an overshoot trajectory, which will in due course reverse and return to the target. In other words, the term suggests that such reversal and return is somehow automatic or easy, perhaps even built into the definition of “overshoot.” But what is actually highly likely is not the complete overshoot trajectory, but the initial exceedance of the target. How large and long-lasting the exceedance is, indeed, whether temperature actually returns to the target at all rather than just staying higher, depends on what happens to net emissions afterwards. Returning to or below the target, let alone doing so after just a small and brief exceedance, will take the same extreme reductions in emissions that have been so challenging to achieve thus far, now with the additional requirement that any continuing emissions be more than offset by extreme scale-up of stable atmospheric removals. Current and coming advances in carbon-free technology will help, of course. But given decades of shortfall in reducing global emissions, and continuing structural factors hindering needed sharp reductions, there is no justification to assume this vast transformation will somehow get easy, let alone automatic, by the mere fact of exceeding the targets and suffering the resultant worse climate impacts. Fossil interests will keep fighting, even if it’s to stretch their demise out longer rather than to live forever. Perhaps increasingly severe climate change and impacts will make transformative socio-technical change easier, but this depends on political assumptions – theories of social change – that are not clear.

An illustration of the deep difficulty thinking coherently about exceedance and overshoot can be found right in the recent IPCC AR6 report—a point the Commission discovered in the course of its work but did not include in its report. The overshoot scenarios reported in the IPCC all fall into two buckets: “low overshoot,” in which 1.5°C is exceeded by at most 0.1°C (this bucket also includes a tiny number of scenarios with no overshoot at all, but to be a little glib, nobody believes those); and “medium to high” overshoot, in which 1.5°C exceeded by 0.1 to 0.3°C.  A casual read could be forgiven for inferring that these numbers reflect a reasoned conclusion by the IPCC that these are the biggest overshoots the world will likely have to deal with. But unfortunately that’s not what it means at all. These buckets with their low overshoot numbers are a definitional artifact, arising from the year-2100 endpoint of the analyses. For a scenario to be called “overshoot,” it had to get back to its target by the year-2100 end of the analytic time horizon. Scenarios that peaked above 1.8°C—i.e., that exceeded 1.5°C by more than 0.3°C this century– did not have time to get back below 1.5°C by the end of the century, so were not labeled or analyzed as overshoot.  Even more so, no scenario that exceeded 2.0°C could be called overshoot, because there is not enough time on any trajectory to exceed 2.0°C, reverse, and return to 2.0°C by the end of the century. So, the overshoot scenarios identified and analyzed as such are in fact the best possible trajectories in which 1.5°C is exceeded, which manage to get back to 1.5°C by 2100. The IPCC in no way ruled out or judged unlikely future trajectories with higher and longer-lasting exceedances. These are there—in fact, they are clustered into buckets by their end-of-century heating.  These include, for example, the scenarios I reported above, in which continuance of present policies or NDC commitments without increasing ambition (granted, a scenario that may be unlikely on the pessimistic, no-action side) give end-of-century heating of 3.2°C and 2.8°C, respectively (with the lower figures subsequently estimated by UNEP and the IEA, as noted above). 

Having sounded the alarm about the likelihood of overshoot—albeit pulling their punches a little in concession to the perceived need to give a positive message—the Commission’s second job was to say what this high risk of overshoot means for climate response.

At first cut, this is a simple story: do more of everything and do it faster. But given the widespread desire not to face the stark likelihood of potentially severe exceedance, there actually is more to say—in particular, that the gravity of risks requires consideration of more extreme or radical approaches to limiting climate change than have gained serious attention thus far. It is no longer acceptable to deem plausible solutions that might help inadmissible a priori.

The Commission did this and did it pretty well—to varying degrees across the four major response types, of which they addressed all – mitigation, adaptation, removals, and solar geoengineering or SRM. Indeed, given the current state of climate debate, merely including all four response types with similar levels of scrutiny and detail represents a significant contribution. They also presented a useful and original conceptual framework for thinking about climate responses in presence of overshoot, dividing the four response types into two pairs according to which of two large-scale aims they pursue: Reducing the magnitude and duration of overshoot; and reducing the harms that follow from any given magnitude and duration of overshoot. The two responses that limit the magnitude and duration of overshoot are mitigation and removal: deep cuts in present and future emissions; and removing past emissions from the atmosphere and putting them somewhere long-term secure. The two ways to limit the harms resultant from any specific magnitude and duration of overshoot are adaptation and solar geoengineering (Sort-of, on the last one: the Commission doesn’t recommend solar geoengineering—in fact, its immediate recommendation is to enact a moratorium on it—but it also recommends researching it and starting to talk about how to resolve the governance problems it would raise). They also separately addressed climate finance; a cross-cutting response relevant to all responses.

From left to right: Kim Campbell (Canada’s 19th Prime Minister, Founding Member of Club de Madrid; Chair Pascal Lamy (Vice President of the Paris Peace Forum; former Director-General of the World Trade Organization, France); Hina Rabbani Khan (Minister of State for Foreign Affairs of Pakistan); Unknown; Xue Lan (Cheung Kong Chair Distinguished Professor and Dean of Schwarzman College, Tsinghua University, China); & Muhamad Chatib Basri (Former Minister of Finance of Indonesia).

I’m going to address how the Commission dealt with each response type in subsequent posts, which I’ll put up at intervals of one or two days. The next two will separately consider the two response types where the Commission’s recommendations are most radical, most original, and most likely to attract controversy: mitigation and solar geoengineering. I’ll then review their analysis and recommendations on adaptation, removals, and climate finance, and close with a review of reactions to the Commission (which should start to be clear by that point) and speculation on its impact.

[Note from BenIndy: All bolded elements above represent added emphasis by BenIndy. You can subscribe to Legal-Planet.org in order to receive notifications for Dr. Parson’s follow-up posts.]