Excerpts from feature reference articles
The awful truth about climate change no one wants to admit. David Roberts, vox. May 15, 2015.
Limiting Global Warming to 2 Degrees Celsius Won’t Save Us. Kate Dooley and Peter Christoff, New Republic. May 27, 2015.
Two degrees: The world set a simple goal for climate change. We're likely to miss it. Brad Plumer, vox. Apr. 22, 2014.
The rate of global temperature rise may have hit a plateau, but a climate crisis still looms in the near future.
related research:
Defining Dangerous Anthropogenic Interference. Michael E. Mann in Proceedings of the National Academy of Sciences USA, Vol. 106, No. 11, pages 4065–4066; March 17, 2009.
Separating Forced from Chaotic Climate Variability over the Past Millennium. Andrew P. Schurer et al. in Journal of Climate, Vol. 26, No. 18, pages 6954–6973; September 2013.
John Carey. Is Global Warming Happening Faster Than Expected? Scientific American. November 1, 2012.
Loss of ice, melting of permafrost and other climate effects are occurring at an alarming pace.
an example of how alarm bells were being rung over 5 years ago:
The brutal logic of climate change. David Roberts, Grist. Dec 6, 2011.
Oliver Geden: Climate advisers must maintain integrity. Nature. May 6, 2015.
Jonathan Chait: Climate Change and Conservative Brain Death. New York Magazine. March 14, 2016.
Dr. Gideon Polya: G7 Pledge of Zero Emissions by 2100 Masks Worsening Climate Emergency and Need for Urgent Action. June 10, 2015.
Renewable Energy After COP21: Nine issues for climate leaders to think about on the journey home.
Richard Heinberg, Post Carbon Institute, Dec 14, 2015.
UN Predicts Disaster if Global Warming Not Checked. Peter James Spielmann, AP News Archive. Jun 29, 1989.
The awful truth about climate change no one wants to admit. David Roberts, vox. May 15, 2015.
"A 4°C warmer world can, and must be, avoided," said the World Bank president.
But that's where we're headed. It will take enormous effort just to avoid that fate. Holding temperature down under 2°C — the widely agreed upon target — would require an utterly unprecedented level of global mobilization and coordination, sustained over decades. There's no sign of that happening, or reason to think it's plausible anytime soon. And so, awful shit it is....
Climate scientists, Geden says, feel pressure to provide the good news. They're worried that if they don't, if they come off as "alarmist" or hectoring, they will simply be ignored, boxed out of the debate. And so they construct models showing that it is possible to hit the 2°C target. The message is always, "We're running out of time; we've only got five or 10 years to turn things around, but we can do it if we put our minds to it." That was the message in 1990, in 2000, in 2010. How can we still have five or 10 years left? The answer, Geden says, is that scientists are baking increasingly unrealistic assumptions into their models.
Can we limit warming to 1.5 degrees Celsius?
The 2 degrees Celsius warming limit or “guardrail” has long been controversial. It was rejected by many developing countries at Copenhagen and over two thirds of Parties to the Convention call for a 1.5 degrees Celsius limit. So is this ambitious temperature limit still within reach?
The carbon budget approach—adopted by the IPCC in its latest report—defines the amounts of cumulative CO2 emissions which will drive warming to a given global temperature limit. The most stringent IPCC scenario gives a remaining (from 2011) carbon budget of 1,000 billion tonnes of CO2, for a “likely” chance of keeping global temperature within 2 degrees Celsius.
Yet whether a lower temperature limit is still within reach, and the pathway to get there, is debated. The more ambitious mitigation scenarios reported by the IPCC are characterized by overshooting the budget and then removing greenhouse gases from the atmosphere. This usually means relying on bioenergy plus carbon capture and storage (burning biomass for energy, removing the CO2, and then storing it underground) to remove carbon from the atmosphere—which comes with its own risks.
1.5 degrees Celsius pathways which do not rely on negative emissions depend on a much lower remaining budget. Even a 50 percent chance of keeping below 1.5 degrees Celsius requires immediate and radical emission reductions. This would mean unprecedented annual rates of decline which are not in line with current levels of energy consumption or ideas of economic growth...
The UNFCC expert group recognized that limiting global warming to below even 2 degrees Celsius necessitates a radical transition, not merely a fine-tuning of current trends, yet such radical emissions reduction pathways are so far excluded from IPCC assessment, leaving policy makers with little evidence on the impacts and feasibility of lower targets.
Where to from here?
The group concluded that the world is not on track to achieve the long-term global goal of 2 degrees Celsius, noting that the longer we wait to bend the curve of global greenhouse gas emissions, the steeper we will have to bend it down later.
Two degrees: The world set a simple goal for climate change. We're likely to miss it. Brad Plumer, vox. Apr. 22, 2014.
It was the early 1990s. Climate scientists had long known that humans were warming up the planet. But politicians were only beginning to appreciate that it would take a staggering coordinated effort to get nations to burn fewer fossil fuels and avoid sharp temperature increases in the decades ahead.
Those policymakers needed a common goal — a way to say, Here’s how bad things will get and This is what we need to do to stop it. But that posed a dilemma. No one could agree on how much global warming was actually unacceptable. How high did the seas need to rise before we had a serious problem? How much heat was too much?
Around this time, an advisory council of scientists in Germany proposed an alluringly simple way to think about climate change. Look, they reasoned, human civilization hasn’t been around all that long. And for the last 12,000 years, Earth’s climate has fluctuated within a narrow band. So, to be on the safe side, we should prevent global average temperatures from rising more than 2° Celsius (or 3.6° Fahrenheit) above what they were just before the dawn of industrialization.
Critics grumbled that the 2°C limit seemed arbitrary or overly simplistic. But scientists were soon compiling evidence that the risks of global warming became fairly daunting somewhere above the 2°C threshold: rapid sea-level rise, the risk of crop failure, the collapse of coral reefs. And policymakers loved the idea of a simple, easily digestible target. So it stuck.
By 2009, nearly every government in the world had endorsed the 2°C limit — global warming beyond that level was widely considered "dangerous." And so, every year, the world’s leaders meet at UN climate conferences to discuss policies and emissions cuts that they hope will keep us below 2°C. Climate experts churn out endless papers on how we can adapt to 2°C of warming or less.
Two decades later, there’s just one huge problem with this picture. The idea that the world can stay below 2°C looks increasingly delusional.
John H. Richardson: When the End of Human Civilization is Your Day Job. Esquire. July 7, 2015.
Among many climate scientists, gloom has set in. Things are worse than we think, but they can’t really talk about it.
Michael E. Mann: How Close Are We to ‘Dangerous’ Planetary Warming?. Huffington Post. Dec. 23, 2015.
Michael E. Mann. Earth Will Cross the Climate Danger Threshold by 2036. Scientific American. April 1, 2014.
Among many climate scientists, gloom has set in. Things are worse than we think, but they can’t really talk about it.
Jason Box: "If even a small fraction of Arctic sea floor carbon is released to the atmosphere, we're f'd."
Now, with one word, Box had ventured into two particularly dangerous areas. First, the dirty secret of climate science and government climate policies is that they're all based on probabilities, which means that the effects of standard CO2 targets like an 80 percent reduction by 2050 are based on the middle of the probability curve. Box had ventured to the darker possibilities on the curve's tail, where few scientists and zero politicians are willing to go.
As a recent study from the University of Bristol documented, climate scientists have been so distracted and intimidated by the relentless campaign against them that they tend to avoid any statements that might get them labeled "alarmists," retreating into a world of charts and data.
"I think most scientists must be burying overt recognition of the awful truths of climate change in a protective layer of denial (not the same kind of denial coming from conservatives, of course). I'm still amazed how few climatologists have taken an advocacy message to the streets, demonstrating for some policy action."
...a study by the U. S. Navy says that the Arctic could lose its summer sea ice by next year, eighty-four years ahead of the models
And yet, despite some encouraging developments in renewable energy and some breakthroughs in international leadership, carbon emissions continue to rise at a steady rate, and for their pains the scientists themselves—the cruelest blow of all—have been the targets of an unrelenting and well-organized attack that includes death threats, summonses from a hostile Congress, attempts to get them fired, legal harassment, and intrusive discovery demands so severe they had to start their own legal-defense fund, all amplified by a relentless propaganda campaign nakedly financed by the fossil-fuel companies. Shortly before a pivotal climate summit in Copenhagen in 2009, thousands of their e-mail streams were hacked in a sophisticated espionage operation that has never been solved
Michael E. Mann: How Close Are We to ‘Dangerous’ Planetary Warming?. Huffington Post. Dec. 23, 2015.
It has been widely reported that 2015 will be the first year where temperatures climbed to 1C above the pre-industrial. That might make it seem like we’ve got quite a ways to go until we breach the 2C limit. But the claim is wrong. We exceeded 1C warming more than a decade ago. The problem is that here, and elsewhere, an inappropriate baseline has been invoked for defining the “pre-industrial.” The warming was measured relative to the average over the latter half of the 19th century (1850-1900). In other words, the base year implicitly used to define “pre-industrial” conditions is 1875, the mid-point of that interval. Yet the industrial revolution and the rise in atmospheric CO2 concentrations associated with it, began more than a century earlier
The IPCC graphic suggests that keeping net CO2 emissions below 3 trillion tons — and thereby stabilizing maximum CO2 concentrations below 450 ppm — would likely keep warming below the “dangerous” 2C limit. Unfortunately, that conclusion is overly optimistic because, once again, it relies on the use of an artificially warm, too-recent baseline for defining the pre-industrial period roughly 0.3C greenhouse warming had already taken place by 1900, and roughly 0.2C warming by 1870
When we take this factor into account (orange dotted curve), the warming for 450 ppm stabilization is now is seen to approach 2.5C, well about the “dangerous” limit. Indeed, CO2 concentrations now have to be kept below 405 ppm (where we’ll be in under three years at current rates of emissions) to avoid 2C warming (blue dotted curve).
So evidently, we don’t have 1/3 of our total carbon budget left to expend, as implied by the IPCC analysis. We’ve already expended the vast majority of the budget for remaining under 2C. And what about 1.5C stabilization? We’re already overdrawn.
The more we delay rapid reductions in fossil fuel burning, the more we will need to offset additional carbon emissions by sequestration of atmospheric carbon, either through massive reforestation projects, or ‘geoengineering’ technology such as “direct air capture,” which involves literally sucking the CO2 back out of the atmosphere
Michael E. Mann. Earth Will Cross the Climate Danger Threshold by 2036. Scientific American. April 1, 2014.
The rate of global temperature rise may have hit a plateau, but a climate crisis still looms in the near future.
If the world continues to burn fossil fuels at the current rate, global warming will rise to two degrees Celsius by 2036, crossing a threshold that will harm human civilization. To avoid the threshold, nations will have to keep carbon dioxide levels below 405 parts per million.
In its September 2013 report, the IPCC extended the stick back in time, concluding that the recent warming was likely unprecedented for at least 1,400 years.
Although the earth has experienced exceptional warming over the past century, to estimate how much more will occur we need to know how temperature will respond to the ongoing human-caused rise in atmospheric greenhouse gases, primarily carbon dioxide. Scientists call this responsiveness “equilibrium climate sensitivity” (ECS). ECS is a common measure of the heating effect of greenhouse gases. It represents the warming at the earth's surface that is expected after the concentration of CO2 in the atmosphere doubles and the climate subsequently stabilizes (reaches equilibrium).
The preindustrial level of CO2 was about 280 parts per million (ppm), so double is roughly 560 ppm. Scientists expect this doubling to occur later this century if nations continue to burn fossil fuels as they do now—the “business as usual” scenario—instead of curtailing fossil-fuel use. The more sensitive the atmosphere is to a rise in CO2, the higher the ECS, and the faster the temperature will rise. ECS is shorthand for the amount of warming expected, given a particular fossil-fuel emissions scenario.
It is difficult to determine an exact value of ECS because warming is affected by feedback mechanisms, including clouds, ice and other factors. Different modeling groups come to different conclusions on what the precise effects of these feedbacks may be. Clouds could be the most significant. They can have both a cooling effect, by blocking out incoming sunlight, and a warming effect, by absorbing some of the heat energy that the earth sends out toward space. Which of these effects dominates depends on the type, distribution and altitude of the clouds—difficult for climate models to predict. Other feedback factors relate to how much water vapor there will be in a warmer atmosphere and how fast sea ice and continental ice sheets will melt.
Because the nature of these feedback factors is uncertain, the IPCC provides a range for ECS, rather than a single number
An ECS of three degrees C means that if we are to limit global warming to below two degrees C forever, we need to keep CO2concentrations far below twice preindustrial levels, closer to 450 ppm. Ironically, if the world burns significantly less coal, that would lessen CO2emissions but also reduce aerosols in the atmosphere that block the sun (such as sulfate particulates), so we would have to limit CO2 to below roughly 405 ppm.
The conclusion that limiting CO2 below 450 ppm will prevent warming beyond two degrees C is based on a conservative definition of climate sensitivity that considers only the so-called fast feedbacks in the climate system, such as changes in clouds, water vapor and melting sea ice. Some climate scientists, including James E. Hansen, former head of the NASA Goddard Institute for Space Studies, say we must also consider slower feedbacks such as changes in the continental ice sheets. When these are taken into account, Hansen and others maintain, we need to get back down to the lower level of CO2 that existed during the mid-20th century—about 350 ppm.Michael E. Mann is Distinguished Professor of Meteorology at Pennsylvania State University and contributed to the International Panel on Climate Change work that received the 2007 Nobel Peace Prize. He has written the book The Hockey Stick and the Climate Wars: Dispatches from the Front Lines, as well as Dire Predictions: Understanding Global Warming.
related research:
Defining Dangerous Anthropogenic Interference. Michael E. Mann in Proceedings of the National Academy of Sciences USA, Vol. 106, No. 11, pages 4065–4066; March 17, 2009.
Separating Forced from Chaotic Climate Variability over the Past Millennium. Andrew P. Schurer et al. in Journal of Climate, Vol. 26, No. 18, pages 6954–6973; September 2013.
John Carey. Is Global Warming Happening Faster Than Expected? Scientific American. November 1, 2012.
Loss of ice, melting of permafrost and other climate effects are occurring at an alarming pace.
Keeping planetary warming below two degrees Celsius (3.6 degrees Fahrenheit) would, it was thought, avoid such perils as catastrophic sea-level rise and searing droughts. Staying below two degrees C would require limiting the level of heat-trapping carbon dioxide in the atmosphere to 450 parts per million (ppm), up from today's 395 ppm and the preindustrial era's 280 ppm.
an example of how alarm bells were being rung over 5 years ago:
The brutal logic of climate change. David Roberts, Grist. Dec 6, 2011.
As you can see, the 2 degrees C “guardrail” that separated acceptable from dangerous in 2001 is, in 2009, squarely inside several red zones. Today, the exact same social and political considerations that settled on 2 degrees C as the threshold of safety by all rights ought to settle on 1 degree C [1.8 degrees F]. After all, we now know 2 degrees C is extremely dangerous.
At this point, however, stopping at 1 degree C is physically impossible (we can thank our past inaction for that). Indeed, as we’ll see, stopping at 2 degrees C is getting close to impossible as well. There is no longer any reasonable chance of avoiding “dangerous” climate change, so 1 degree C vs. 2 degrees C is a somewhat academic debate. At this point we’re just shooting to avoid super-duper-dangerous. ...
The thing is, if 2 degrees C is extremely dangerous, 4 degrees C is absolutely catastrophic. In fact, according to the latest science, says Anderson, “a 4 degrees C future is incompatible with an organized global community, is likely to be beyond ‘adaptation’, is devastating to the majority of ecosystems, and has a high probability of not being stable.”...
Oh, and by the way: According to the International Energy Agency, we’re currently on course for 6 degrees C [10.8 degrees F]. That is, beyond any reasonable doubt, game over.
Oliver Geden: Climate advisers must maintain integrity. Nature. May 6, 2015.
The negotiations' goal has become what is politically possible, not what is environmentally desirable. Gone is a focus on establishing a global, 'top down' target for stabilizing emissions or a carbon budget that is legally binding. The Paris meeting will focus on voluntary, 'bottom up' commitments by individual states to reduce emissions.
There is another casualty: scientific advice. Climate scientists and economists who counsel policy-makers are being pressured to extend their models and options for delivering mitigation later. This has introduced dubious concepts, such as repaying 'carbon debt' through 'negative emissions' to offset delayed mitigation — in theory.
Scientific advisers must resist pressures that undermine the integrity of climate science. Instead of spreading false optimism, they must stand firm and defend their intellectual independence, findings and recommendations — no matter how politically unpalatable
Climate researchers who advise policy-makers feel that they have two options: be pragmatic or be ignored. They either distance themselves from the policy process by declaring that it is no longer possible to stay within a 2 °C-compatible carbon budget, or they suggest practical ways to dodge carbon-budget constraints3.
Many advisers are choosing pragmatism. This can lead to paradoxical positions, as exemplified by shifting assumptions in climate economics over the past few years.
Each year, mitigation scenarios that explore policy options for transforming the global economy are more optimistic4 — and less plausible. Advisers once assumed that the global emissions peak would have to be reached before 2020 and that annual emissions-reduction rates of more than 3% were not feasible. Those assumptions keep changing.
For example, the fourth assessment of the Intergovernmental Panel on Climate Change (IPCC), published in 2007, stated that emissions must peak by 2015 to stay within 2 °C of warming; yet the fifth IPCC report, released last year, refers to 2030 emissions levels higher than today's that are still compatible with this limit, albeit with annual emissions-reduction rates of 6%
climate economists got around past 'make-or-break' points for the 2 °C target by adding 'negative emissions' — the removal of greenhouse gases from the atmosphere during the second half of this century. Most models assume that this can be achieved using a combination of approaches known as BECCS: bioenergy (which would require 500 million hectares of land — 1.5 times the size of India)4 and carbon capture and storage, an unproven technology.
The climate policy mantra — that time is running out for 2 °C but we can still make it if we act now — is a scientific nonsense. Advisers who shy away from saying so squander their scientific reputations and public trust in climate research
Everyday politics is therefore dominated not by evidence-based policy-making but by attempts at 'policy-based evidence-making'.
Jonathan Chait: Climate Change and Conservative Brain Death. New York Magazine. March 14, 2016.
asked about climate change, and Marco Rubio supplied an answer that, while banal and dogmatic, was fascinating in its own way… Rubio repeated his formulaic and un-categorical opposition to any policy to limit the greenhouse-gas emissions that are in the process of sinking his home city. Rubio’s reply was not just the last gasp of a dying campaign, but a state-of-the-art expression of party doctrine. Trump is what the regular Republicans are trying to stave off; Rubio represents what they are fighting to preserve: a delusional anti-government ideology unable to process or cope with real-world conditions.
The green-energy revolution is really two revolutions acting in tandem: an increase in political willpower, and the rise of new technologies to reduce carbon usage. The two forces interact with each other in powerful ways. As elected officials commit to emissions reductions, the market invests in clean energy technologies, bringing down their price; and as transitioning to lower emissions gets cheaper and more convenient, elected officials can promise deeper reductions still. Rubio revealed the mind-set of a party that remains fully in denial of all this — not just the science but the diplomatic and technological transformation now well under way. The horror of the populist insurgency besieging the GOP from its perimeter has diverted attention from the deep intellectual rot at its core
Dr. Gideon Polya: G7 Pledge of Zero Emissions by 2100 Masks Worsening Climate Emergency and Need for Urgent Action. June 10, 2015.
The June 2015 G7 pledges of (a) zero emissions by 2100 and (b) avoidance of a plus 2 degrees C temperature rise were greeted as “the end of fossil fuels”. Unfortunately (a) the World will exceed its Terminal Carbon Budget for a 75% probability of avoiding plus 2 degrees C in about 3 years, and (b) a plus 2 degrees C temperature rise is disastrous for Humanity and the Biosphere, yielding at equilibrium sea levels “at least 6 to 8 metres higher” according to Dr James Hansen of NASA
Dr Andrew Glikson (a paleoclimate scientist and earth scientist, ANU, Canberra, Australia) (2008), “For some time now, climate scientists warned that melting of subpolar permafrost and warming of the Arctic Sea (up to 4 degrees C during 2005–2008 relative to the 1951–1980) are likely to result in the dissociation of methane hydrates and the release of this powerful greenhouse gas into the atmosphere
Dr. T. Goreau (President of the Global Coral Reef Alliance, an international NGO for restoration of coral reefs, and a member of the Jamaican delegation to UNCCC; previously Senior Scientific Affairs Officer at the United Nations Centre for Science and Technology for Development, in charge of Global Climate Change and Biodiversity issues, where he contributed to the original draft of the UN Framework Convention on Climate Change) (2009): “The long-term sea level that corresponds to current CO2 concentration is about 23 meters above today's levels, and the temperatures will be 6 degrees C or more higher. These estimates are based on real long term climate records, not models"
Dr James Hansen (a leading US climate scientist, former head of the NASA Goddard Institute for Space Studies in New York City, a part of the Goddard Space Flight Center in Greenbelt, Maryland, an adjunct professor in the Department of Earth and Environmental Sciences at Columbia University, first warned the US Congress about the danger from man-made climate change over 20 years ago, and published “Storms of My Grandchildren” in 2009) (2015): “2 degrees is actually a prescription for disaster. That's actually well understood by the scientific community. We know that the prior interglacial period about 120,000 years ago – its called the Eemian in Europe – was less than 2C warmer than pre-industrial conditions and sea level was a least 6 to 8 metres higher, so it's crazy to think that 2 degrees Celsius is a safe limit… make the price of fossil fuels honest”
Renewable Energy After COP21: Nine issues for climate leaders to think about on the journey home.
Richard Heinberg, Post Carbon Institute, Dec 14, 2015.
UN Predicts Disaster if Global Warming Not Checked. Peter James Spielmann, AP News Archive. Jun 29, 1989.
Noel Brown, director of the New York office of the U.N. Environment Program, or UNEP, said governments have a 10-year window of opportunity to solve the greenhouse effect before it goes beyond human control.... He said even the most conservative scientists ''already tell us there's nothing we can do now to stop a ... change'' of about 3 degrees.
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