Scientists have found that humans have just past the half-way point by letting "about 520 billion tons of carbon to the atmosphere."
These predictions were found in the lead editorial in the latest edition of the scientific journal, Nature which reports "at least 9 billion tonnes a year" and that: "If present trends continue, humankind will have emitted a trillion tonnes of carbon into the atmosphere well before 2050, and that could be enough to push the planet into the danger zone. And there is no reason to think that the pressure will stop then. The coal seams and tar sands of the world hold enough carbon for humankind to emit another trillion tonnes — and the apocalyptic scenarios extend from there."
"Yet only a third of economically recoverable oil, gas and coal reserves can be burned before 2100 if that 2°C warming is to be avoided. Faced with this climate crunch, three news features ask: will cutting back on carbon be tougher than we think? Can we drag CO2 directly from the air? And could we cool the planet with a wisp of mist? The worst-case scenario is a world in 2100 that has twice the level of pre-industrial CO2 in the atmosphere." If we want to avoid that, the time for action is now, says Nature.
Wired Science reports: "What matters is the total amount of carbon that we release into the atmosphere, and focusing on that number as a budget can shape the way policymakers look at the problem, argues Myles Allen, lead author of one of the papers and a climatologist at the University of Oxford."
Myles Allen continued: “Reducing emissions steadily over 50 years is much cheaper and easier and less traumatic than allowing them to rise for 15 years and then reducing them violently for 35 years.”
The Nature editorial addresses the urgent necessity to reduce carbon dioxide being dumped into the atmosphere by calling political leaders to take immediate action: "Governments have a wide range of pollution-cutting tools at their command, most notably tradable permit regimes, taxes on fuels, regulations on power generation and energy efficiency, and subsidies for renewable energy and improved technologies. These tools can work if applied seriously — so citizens around the world must demand that seriousness from their leaders, both within their individual nations and in the international framework that will be discussed at the United Nations Climate Change Conference in Copenhagen this December."
The crux of the emissions problem lies with the carbon that has been released into the Earth's atmosphere causing an already dangerous problem that has initiated climate change with specific consequences presented by the world's poorest nations and will require cooperation between rich and poor nations.
Scientists working with the problem of climate change have determined a baseline for the changing of the atmosphere that has been determined to cause: "Dangerous change, even loosely defined, is going to be hard to avoid,” write Gavin Schmidt of the NASA Goddard Institute for Space Science and David Archer, a geoscientist at the University of Chicago, in an accompanying commentary in Nature. “Unless emissions begin to decline very soon, severe disruption to the climate system will entail expensive adaptation measures and may eventually require cleaning up the mess by actively removing CO2 from the atmosphere.”
The Nature editorial continues by arguing that: "The latest scientific research suggests that even a complete halt to carbon pollution would not bring the world's temperatures down substantially for several centuries. If further research reveals that a prolonged period of elevated temperatures would endanger the polar ice sheets, or otherwise destabilize the Earth system, nations may have to contemplate actively removing CO2 from the atmosphere. Indeed, the United Nations Intergovernmental Panel on Climate Change is already developing scenarios for the idea that long-term safety may require sucking up carbon, and various innovators and entrepreneurs are developing technologies that might be able to accomplish that feat. At the moment, those technologies seem ruinously expensive and technically difficult. But if the very steep learning curve can be climbed, then the benefits will be great."
The Nature editorial also discusses possibilities that are: "More radical still is the possibility of cooling the planet through some kind of 'geoengineering' that would dim the incoming sunlight (see page 1097). The effects of such approaches are much more worrying than those of capturing carbon from the air, however. The cooling from geoengineering would not exactly balance the warming from greenhouse gases, which would cause complications even if the technology itself was feasible — something for which the evidence has been circumstantial, at best."
The obvious answer lies with: "Forcing emissions to decline will require changing the way the world uses fossil fuels. In Allen’s view, humans can pull a trillion tons of carbon-rich fossil fuels out of the ground and burn them with risks that have been deemed acceptable by most people. But it’s the second trillion tons of fossil fuels, largely in the form of coal and oil shale, that will determine how recklessly humans play with the climate system.
“From all the incredible arcane arguments that go on, in the end, it’s really a very simple question: what are we going to do with the second trillion tons?” Allen asked. The quantifiable nature of the problem lies with the the conundrum that: "ossil-fuel–reserve estimates vary. While it’s clear that there is a lot of coal and oil shale on Earth, there is intense debate over how much of that fossil fuel will be economical to mine. Allen’s group used the World Energy Council’s estimates, which show nearly 6 trillion tons of fossil fuels still left to be mined. Other scientists believe that fossil fuel reserves could be much lower."
In the meantime: "discussions about the possibilities offered by geoengineering could also lull the world's leaders into complacency" says the Nature editorial, "they lead them to believe that the technology will provide an escape hatch if the climate ever does reach a tipping point. This does not mean that the discussions should be avoided, but rather that the speculations need to be backed up with a solid body of research. Moreover, geoengineering research should be framed not as a hope for deus ex machina fixes to sudden global deterioration, but as a palliative cushion for the worst excesses of the peak years that are inevitable even after emissions start to be cut. A world slightly shaded from the Sun while its carbon levels are brought down by means of active capture would be a strangely unnatural place — but not necessarily a bad one, compared with the alternatives."
Methods to cool the Earth are desparately needed now in order to better inform climatologists of the exact nature of the problems they face. The Nature editorial distinguishes between "far-off goals" and "obscure short-term opportunities." The Nature opinion piece notes that: "In addition to cutting CO2 emissions, global leaders should curb the release of other substances warming the climate, notably methane and soot, also known as 'black carbon'. Tackling such pollutants will bring other benefits, too, such as reducing the respiratory problems associated with cooking over smoky fires and with high levels of tropospheric ozone."
The Nature editorial admits a sense of insurmountability when considering the global climate crisis; but sounds the call that: "there is still time left to act, and there is hope to be found in human ingenuity. Humans have a long history of finding new ways to tackle problems, and new ways to circumvent the worst. Without commitment from the highest levels, such ingenuity is likely to come to naught. But with such a commitment, and with a worldwide determination to make a serious cut in emissions, there is much that can usefully, and invigoratingly, be done."
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