Last year, atmospheric carbon dioxide briefly crossed 400 parts per million for the first time in human history. However, it didn’t cross that threshold until mid-May. This year’s first 400 ppm reading came a full two months earlier this past week and the seeming inexorable upward march is likely to race past another milestone next month.
“We’re already seeing values over 400. Probably we’ll see values dwelling over 400 in April and May. It’s just a matter of time before it stays over 400 forever,” said Ralph Keeling in a blog post.
Keeling runs a carbon dioxide monitoring program for Scripps Institute of Oceanography, a position he took over from his father who started it. The program takes daily measurements from the Mauna Loa Observatory in Hawaii, which sits at 11,141 feet on a volcano’s northern flank. Measurements have been recorded there continuously since March 1958. They’ve risen steadily since the first measurement of 313 ppm as humans have continued to burn more fossil fuels.
CO2 on Path to Cross 400 ppm Threshold for a Month by Brian Kahn, Climate Central, Mar 18, 2014
Despite cold and snowy winters for the past few years, scientists say it hasn’t helped to slow the retreat of the glaciers in Western Canada.
Experts from Natural Resources Canada and several universities monitor annual fluctuations of glaciers in the western and northern Cordillera, which includes the iconic icefields in the Rocky Mountains.
Glaciers in Western Canada still receding despite cold, snow by Colette Derworiz, Calgary Herald, Mar 16, 2014
Climate change will displace hundreds of millions of people by the end of this century, increasing the risk of violent conflict and wiping trillions of dollars off the global economy, a forthcoming UN report will warn.
The second of three publications by the UN’s Intergovernmental Panel on Climate Change, due to be made public at the end of this month, is the most comprehensive investigation into the impact of climate change ever undertaken. A draft of the final version seen by The Independent says the warming climate will place the world under enormous strain, forcing mass migration, especially in Asia, and increasing the risk of violent conflict.
Based on thousands of peer-reviewed studies and put together by hundreds of respected scientists, the report predicts that climate change will reduce median crop yields by 2 per cent per decade for the rest of the century – at a time of rapidly growing demand for food. This will in turn push up malnutrition in children by about a fifth, it predicts.
Official prophecy of doom: Global warming will cause widespread conflict, displace millions of people and devastate the global economy by Tom Bawden, The Independent, Mar 18, 2014
An international team of scientists has discovered that the last remaining stable portion of the Greenland ice sheet is stable no more.
The finding, which will likely boost estimates of expected global sea level rise in the future, appears in the March 16 issue of the journal Nature Climate Change.
The new result focuses on ice loss due to a major retreat of an outlet glacier connected to a long \"river\" of ice - known as an ice stream - that drains ice from the interior of the ice sheet. The Zachariae ice stream retreated about 20 kilometers (12.4 miles) over the last decade, the researchers concluded. For comparison, one of the fastest moving glaciers, the Jakobshavn ice stream in southwest Greenland, has retreated 35 kilometers (21.7 miles) over the last 150 years.
Greenland implicated further in sea-level rise, Phys.org, Mar 16, 2014
Over the past few years, the climate fight has been predominantly fixated on a single piece of symbolic infrastructure, the Keystone XL pipeline, whose recent environmental impact statement from the US State Department has set the stage for a green-lighting of the project.
As activism heats up in response, environmental organizations are likely to pull out all the stops to prevent tar sands extraction and shipment, including growing more powerful connections with both potential and already established allies. In particular, mainstream environmental NGOs and First Nations have increasingly worked in solidarity and aligned with one another in the past year.
Indigenous Voices in Climate Activism: Autonomous or Subjugated? Op-ed by Sarah Santiago, Truthout, Mar 17, 2014
The climate change debate has been abandoned to “conspiracy theorists and keyboard warriors, the social media trolls and the angry shouts of talkback radio”, Bill Shorten says, and scientists should feel insulted their peer-reviewed research is being subject to “feelpinions”.
The opposition leader gave a speech to a “Science meets Parliament” event on Monday in which he said the Labor party would not walk away from action on climate change but the debate had suffered because of people using one-off weather events to justify their science.
He said consensus needed to be built on climate change, with scientists defending their findings more vigorously.
‘Keyboard warriors’ have taken over climate debate, Bill Shorten says by Birdie Jabour, The Guardian, Mar 17, 2014
Stability in the rapidly changing Arctic is a rarity. Yet for years researchers believed the glaciers in the frigid northeast section of Greenland, which connect to the interior of the country’s massive ice sheet, were resilient to the effects of climate change that have affected so much of the Arctic.
But new data published Sunday in Nature Climate Change reveals that over the past decade, the region has started rapidly losing ice due to a rise in air and ocean temperatures caused in part by climate change. The increased melt raises grave concerns that sea level rise could accelerate even faster than projected, threatening even more coastal communities worldwide.
New Greenland Ice Melt Fuels Sea Level Rise Concerns by Brian Kahn, Climate Central, Nov 16, 2014
On March 12, researchers reported that carbon dioxide concentrations in the atmosphere moved above 400 parts-per-million en route to a springtime peak. During spring, trees and other plants begin to draw down CO2 levels to fuel leaf growth. But this is the second time in as many years that levels have risen above 400 ppm, a mark never before experienced in the entire time our species has walked the Earth.
So the important question is: exactly how sensitive is the Earth's climate to these ever-increasing greenhouse gases? Will warming happen gradually or quickly, and to what extent? Even more importantly, how can we find out without the potentially catastrophic experiment we are presently running?
Realistic Climate Models Exhibit Greenhouse Gas Sensitivity by David Biello, Scientific American, Mar 16, 2014
Scientific consensus that humans cause climate change is akin to the scientific consensus that smoking causes cancer, says a report released today by the American Association for the Advancement of Science.
The report, called "What We Know," marks the kickoff of a new AAAS initiative to increase dialogue on the risks of climate change.
"Opinion polls show that more than half of the American public still think that there is a debate over whether climate change is happening or whether it is human-caused," said James McCarthy, a Harvard University oceanographer and co-chairman of the report.
Science Society Seeks to Shift Dialogue on Climate Change by Showing "What We Know by Stephanie Paige Ogburn and ClimateWire, Scientific American, Mar 18, 2014
Early in his career, a scientist named Mario J. Molina was pulled into seemingly obscure research about strange chemicals being spewed into the atmosphere. Within a year, he had helped discover a global environmental emergency, work that would ultimately win a Nobel Prize.
Now, at 70, Dr. Molina is trying to awaken the public to an even bigger risk. He is spearheading a committee of the American Association for the Advancement of Science, the world’s largest general scientific society, which will release a stark report Tuesday on global warming.
The report will warn that the effects of human emissions of heat-trapping gases are already being felt, that the ultimate consequences could be dire, and that the window to do something about it is closing.
Scientists Sound Alarm on Climate by Justin Gillis, New York Times, Mar 18, 2014
Last Friday, I posted an exclusive report about a new NASA-backed scientific research project at the US National Socio-Environmental Synthesis Center (Sesync) to model the risks of civilisational collapse, based on analysis of the key factors involved in the rise and fall of past civilisations.
The story went viral and was quickly picked up by other news outlets around the world which, however, often offered rather misleading headlines. 'Nasa-backed study says humanity is pretty much screwed', said Gizmodo. 'Nasa-funded study says modern society doomed, like the dodo', said the Washington Times.
The global Transition tipping point has arrived - vive la revolution by Nafeez Ahmed, Earth Insight, The Guardian, Mar 22, 2014
If the world continues to burn fossil fuels at the current rate, global warming will rise 2 degrees Celsius by 2036, crossing a threshold that many scientists think will hurt all aspects of human civilization: food, water, health, energy, economy and national security. In my article "False Hope" in the April 2014 Scientific American, I reveal dramatic curves that show why the world will reach this temperature limit so quickly, and also why the recent slowdown in the rate of temperature increase, if it continues, will only buy us another 10 years.
These numbers come from calculations made by me and several colleagues. We plugged values of Earth’s “equilibrium climate sensitivity”—a common measure of the heating effect of greenhouse gases—into a so-called energy balance model. Scientists use the model to investigate possible climate scenarios.
You can try this exercise yourself. The text below explains the variables and steps involved. You can download the climate data here and the model code here. And you can compare your results with mine, which are here. You can also change the variables to see what other future scenarios are possible. One note: the model runs on MatLab software, which can be obtained here.
Why Global Warming Will Cross a Dangerous Threshold in 2036 by Michael E. Mann, Scientific American, Mar 18, 2014
Posted by John Hartz on Tuesday, 18 March, 2014
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