Categories

Archives

A sample text widget

Etiam pulvinar consectetur dolor sed malesuada. Ut convallis euismod dolor nec pretium. Nunc ut tristique massa.

Nam sodales mi vitae dolor ullamcorper et vulputate enim accumsan. Morbi orci magna, tincidunt vitae molestie nec, molestie at mi. Nulla nulla lorem, suscipit in posuere in, interdum non magna.

Climate Reports Forecast Dire Future, Even If Action Is Taken

In the absence of aggressive government policies aimed at curbing greenhouse gas emissions, a number of leading organizations, including the United Nations, the World Bank and others, have begun issuing analyses that regard potentially dangerous temperature elevations as not just a possibility should the status quo prevail, but a near certainty even if things start to change.

The latest report, released Wednesday by the United Nations Environment Program, suggested that greenhouse gas emissions levels are currently around 14 percent above where they need to be by the end of the decade in order to avoid what many analysts believe could be a risky level of planetary warming.

That report comes on the heels of a study issued Tuesday by the Geneva-based World Meteorological Organization, which stated that human civilization has pumped roughly 375 billion tonnes, or metric tons, of carbon dioxide into the atmosphere since the dawn of the industrial age, when the extraction and combustion of fossil fuels began in earnest.

“These billions of tonnes of additional carbon dioxide in our atmosphere will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth,” said WMO Secretary-General Michel Jarraud, in a statement issued Tuesday. “Future emissions will only compound the situation.”

On Sunday, the World Bank issued a report suggesting that the climate could warm a full 4 degrees by the end of the century — less than 90 years from now — even if countries fulfill the modest emissions-reduction pledges they’ve already made.

A 4-degree uptick in temperatures is significantly higher than what has long been deemed the maximum amount — 2 degrees Celsius, or 3.6 degrees Fahrenheit — that average global temperatures could rise while still maintaining a climate similar to that in which human civilization has evolved.

That number, measured against things as they existed before the industrial-scale use of fossil fuels got underway, was not considered absolute. But the best evidence seemed to suggest that keeping the Earth’s average temperature from rising much beyond 2 degrees was a worthy goal, not least because larger increases would raise the odds of many unpleasant things: forbidding sea levels, searing heat waves, grinding droughts and the like.

In subsequent years, some prominent scientists argued that even 2 degrees of warming would be disastrous.

But increasing evidence suggests that such distinctions may no longer matter.

Nearly 30 years after the benchmark was proffered, about half the distance to a 2-degree temperature increase, or about 0.8 degrees, has already been achieved. Further, enough carbon dioxide, the chief planet warming gas that arises when coal, oil and natural gas are burned, is already in the atmosphere to raise future temperatures by another 0.8 degrees, even if all the pollution stopped immediately.

As it is, atmospheric levels of carbon dioxide are at an all-time high and are projected to continue booming.

Carbon dioxide is, of course, naturally present in the atmosphere — and necessary for retaining some of the sun’s warmth and creating a habitable climate. But all that extra, human-produced carbon dioxide is amplifying the natural greenhouse effect, and driving up the planetary thermostat.

So much so that PricewaterhouseCoopers, the global business consultancy, issued a report earlier this month that makes the 2-degree Celsius threshold appear quaint. That analysis, titled “Too Late for Two Degrees?,” suggested that while efforts to reduce the carbon intensity, or the amount of emissions per unit of GDP, of the world’s economies are making some modest gains, they are unfolding so slowly as to be negligible.

“Even doubling our current rate of decarbonization, would still lead to emissions consistent with 6 degrees of warming by the end of the century,” noted Leo Johnson, a partner in PwC’s Sustainability and Climate Change unit, in the report. “To give ourselves a more than 50 percent chance of avoiding 2 degrees will require a six-fold improvement in our rate of decarbonization.”

Put another way, the PwC researchers concluded, to have even a modest chance of staying within the 2-degree threshold, the global economy would need to reduce overall carbon intensity by 5.1 percent every year for the next 40 years.

chart

Atmospheric carbon dioxide concentrations at Mauna Loa Observatory, Hawaii.

Reductions in overall carbon intensity have occurred — particularly during times of steep recession, when economies are producing less and, as such, burning fewer fossil fuels. But reductions of 5 percent have never been achieved in any year since World War II, the PwC report noted, much less year after year for decades. And given the fast-expanding and fossil-fuel dependent economies of countries like China and India, such reductions are exceedingly unlikely, the authors suggested.
More huffingtonpost.com

Share

Leave a Reply