Wednesday 17 September 2014

Climate change news

Earth Surface During August of 2014 Was Hottest Ever Recorded


16 September, 2014
The monthly global temperature records just keep falling…
Despite no El Nino declared, an extraordinarily hot global ocean surface keeps dumping heat back into the atmosphere. This transfer resulted in the hottest March-through-May period in the global record and has pushed numerous record spikes in the global measures this summer. By August, according to NASA, the global average had again climbed to never-before-seen levels.
As of yesterday’s report, NASA showed that the Global Land-Ocean Surface Temperature Index had climbed to 0.70 degrees Celsius above the mid 20th Century average and about 0.95 degrees Celsius above the 1880s average. The previous record high for the period was set in 2011 at 0.69 degrees C above the global 1951 to 1980 average.

global temp maps
(Global surface temperature departures according to NASA GISS. Image source: NASA.)
Throughout the world, global ocean surface temperatures showed extraordinary departures above average for the month. Greater variance was experienced over continental land masses and over the polar regions.

Zonal anomalies showed far greater heat amplification near the southern polar region, especially in the region near 80 south latitude. In the Northern Hemisphere the tundra region near 60 north latitude focusing in Northeast Siberia near the methane emitting zone of the East Siberian Arctic Shelf, the region north of the Caspian Sea, and Baffin Bay and Northeast Canada showed the greatest high temperature anomalies. Only the high Arctic and regions in or near the southern ocean showed widespread and significant cooler than average zonal readings.

You can see these zonal anomalies in the graph provided by NASA below:

August zonal anomalies
(Temperature departures by latitudinal zone. Image source: NASA.)
A Catastrophic Pace of Warming

To understand these record high global temperatures, it is useful to consider the broader paleo-climate context. In this context, the global temperature difference between 1880 and the last ice age was about 5 degrees Celsius. So the current temperature departure, driven by human greenhouse gas emissions, is equal to about 1/5 the difference between the 19th century and an ice age, but on the side of hot.
As it took about 12,000 years for the post ice-age warming to occur, the recorded pace of warming since 1880 is about 20 times faster than that period of extreme Earth system change. With the predicted pace of warming expected to increase even further and with ice sheets still covering the surface of the Earth (which greatly help to mitigate the pace of warming spikes), this current velocity of change is both likely unprecedented and catastrophic.
Links:

Methane levels threaten to skyrocket

10 Setpember, 2014

The World Meteorological Organization’s annual Greenhouse Gas Bulletin shows that between 1990 and 2013 there was a 34% increase in radiative forcing – the warming effect on our climate – because of long-lived greenhouse gases such as carbon dioxide (CO2), methane and nitrous oxide.

In 2013, concentration of CO2 in the atmosphere was 142% of the pre-industrial era (1750), and of methane and nitrous oxide 253% and 121% respectively.

The ocean cushions the increase in CO2 that would otherwise occur in the atmosphere, but with far-reaching impacts. The current rate of ocean acidification appears unprecedented at least over the last 300 million years, according to an analysis in the report.

“We know without any doubt that our climate is changing and our weather is becoming more extreme due to human activities such as the burning of fossil fuels,” said WMO Secretary-General Michel Jarraud.



NOAA data give a slightly lower CO2 growth figure for 2013, but even when extrapolating NOAA's data, some frightening trendlines appear, as illustrated by above image. 

The WMO concludes that a reduction in RF (radiative forcing) from its current level (2.92 W·m–2 in 2013) will require huge cuts in a number of emissions, not just in CO2. 

In the figure on the right, the RF of the long-lived greenhouse gases (LLGHG) is plotted along with different emission reduction scenarios: (a) emissions held constant at 2013 levels, (b) constant CO2 emissions and 80% reduction in anthropogenic non-CO2 GHG emissions, (c) 80% reduction in CO2 emissions while non-CO2 GHG emissions are held constant, and (d) 80% reductions in all LLGHG emissions.


A recent study shows that the world not only continues to build new coal-fired power plants, but built more new coal plants in the past decade than in any previous decade. Worldwide, an average of 89 gigawatts per year (GW yr–1) of new coal generating capacity was added between 2010 and 2012, 23 GW yr–1 more than in the 2000–2009 time period and 56 GW yr–1 more than in the 1990–1999 time period. Natural gas plants show a similar pattern.

Assuming these plants operate for 40 years, the fossil-fuel burning plants built in 2012 will emit approximately 19 billion tons of CO2 (Gt CO2) over their lifetimes, versus 14 Gt CO2 actually emitted by all operating fossil fuel power plants in 2012.

The study concludes that total committed emissions related to the power sector are growing at a rate of about 4% per year.

“Bringing down carbon emissions means retiring more fossil fuel-burning facilities than we build,” said Steven Davis, assistant professor of Earth system science at UCI and the study’s lead author. “But worldwide, we’ve built more coal-burning power plants in the past decade than in any previous decade, and closures of old plants aren’t keeping pace with this expansion.”

“Far from solving the climate change problem, we’re investing heavily in technologies that make the problem worse,” he added.
“We’ve been hiding what’s going on from ourselves: A high-carbon future is being locked in by the world’s capital investments,” said Socolow, professor emeritus of mechanical & aerospace engineering.

The IPCC in AR5 suggests there was a carbon budget to divide between nations (above image left), while largely ignoring potentially huge feedbacks such as albedo changes resulting from decline of snow and ice in the Arctic and methane eruptions from the seafloor of the Arctic Ocean.

These two feedbacks alone could each soon cause more warming than the warming directly caused by people's emissions since the start of the industrial revolution.

Sam Carana says: “There is no carbon budget to divide between nations, instead there is just a huge debt of CO2 to be removed from the atmosphere and the oceans. Comprehensive and effective action must be taken to stop run-away warming.”

Sam Carana continues: “No time before in human history has such a huge amount of ocean heat accumulated in the North Atlantic and the North Pacific.”

“This heat is now threatening to invade the Arctic Ocean and trigger huge temperature rises due to methane eruptions from the seafloor.”

“The heat is also melting Arctic sea ice from below, as the image below right shows, there now is hardly any sea ice left that is more than 3 meters (nearly 10 ft) thick.”
“Last year, this heat started to cause large methane eruptions from the Arctic Ocean's seafloor in early October, and this year temperatures in the Arctic Ocean are even higher.”

Meanwhile, mean global methane levels of 1839 ppb were recorded at several altitudes by the MetOp-1 satellite on the morning of September 7, 2014.

And ocean heat continues to invade the Arctic, as illustrated by the NOAA image below.



References

- Record Greenhouse Gas Levels Impact Atmosphere and Oceans - WMO Press Release No. 1002
https://www.wmo.int/pages/mediacentre/press_releases/pr_1002_en.html

- WMO Greenhouse Gas Bulletin No. 10 | 9 September 2014
https://www.wmo.int/pages/mediacentre/press_releases/documents/1002_GHG_Bulletin.pdf

- NOAA Trends in Atmospheric Carbon Dioxide, Annual Mean Global CO2 Growth Rates
http://www.esrl.noaa.gov/gmd/ccgg/trends/global.html#global_growth

- Commitment accounting of CO2 emissions, by Steven J Davis and Robert H Socolow
http://iopscience.iop.org/1748-9326/9/8/084018

- Existing power plants will spew 300 billion more tons of carbon dioxide during use - News Release
http://news.uci.edu/press-releases/existing-power-plants-will-spew-300-billion-more-tons-of-carbon-dioxide-during-use

Why Greenland’s “Dark Snow” Should Worry You
By Eric Holthaus


16 September, 2014

Jason Box knows ice. That’s why what’s happened this year concerns him so 
much.

Box just returned from a trip to Greenland. Right now, the ice there is … black:.




Photo by Jason Box
Dark ice is helping Greenland’s glaciers retreat.
Photo by Jason Box



Photo by Jason Box
Crevasses criss-cross the Greenland ice sheet, allowing melt water to descend deep beneath the ice.
Photo by Jason Box



Photo by Jason Box
This year, Greenland’s ice was the darkest it’s ever been.
Photo by Jason Box



Photo by Jason Box
Box and his team are trying to discover what made this year’s melt season so unusual.
Photo by Jason Box



Photo by Jason Box
Box marks his study sites, appropriately, with black flags.
Photo by Jason Box



Photo by Jason Box
Box’s ‘Dark Snow’ project is the first scientific expedition to Greenland to be crowdfunded.
Photo by Jason Box
The ice in Greenland this year isn’t just a little dark—it’s record-setting dark. Box says he’s never seen anything like it. I spoke to Box by phone earlier this month, just days after he returned from his summer field research campaign.

 “I was just stunned, really,” Box told me.
The photos he took this summer in Greenland are frightening. But their implications are even more so. Just like black cars are hotter to the touch than white ones on sunny summer days, dark ice melts much more quickly.
As a member of the Geological Survey of Denmark and Greenland, Box travels to Greenland from his home in Copenhagen to track down the source of the soot that’s speeding up the glaciers’ disappearance. He aptly calls his crowdfunded scientific survey Dark Snow.




Courtesy of The National Snow and Ice Data Center
This year was another above-average melt season in Greenland.
Courtesy of The National Snow and Ice Data Center
There are several potential explanations for what’s going on here. The most likely is that some combination of increasingly infrequent summer snowstorms, wind-blown dust, microbial activity, and forest fire soot led to this year’s exceptionally dark ice. A more ominous possibility is that what we’re seeing is the start of a cascading feedback loop tied to global warming. Box mentions this summer’s mysterious Siberian holes and offshore methane bubbles as evidence that the Arctic can quickly change in unpredictable ways.

This year, Greenland’s ice sheet was the darkest Box (or anyone else) has ever measured. Box gives the stunning stats: “In 2014 the ice sheet is precisely 5.6 percent darker, producing an additional absorption of energy equivalent with roughly twice the US annual electricity consumption.”
Perhaps coincidentally, 2014 will also be the year with the highest number of forest fires ever measured in Arctic.
Box ran these numbers exclusively for Slate, and what he found shocked him. Since comprehensive satellite measurements began in 2000, never before have Arctic wildfires been as powerful as this year. In fact, over the last two or three years, Box calculated that Arctic fires have been burning at a rate that’s double that of just a decade ago. Box felt this finding was so important that he didn’t want to wait for peer review, and instead decided to publish first on Slate. He’s planning on submitting these and other recent findings to a formal scientific journal later this year.




Photo by Jason Box/NASA
Arctic and sub-Arctic fires were more powerful in 2014 than ever recorded before.
Photo by Jason Box/NASA

Box’s findings are in line with recent research that shows the Arctic is in the midst of dramatic change.

A recent study has found that, as the Arctic warms, forests there are turning to flame at rates unprecedented in the last 10,000 years. This year, those fires produced volumes of smoke and soot that Box says drifted over to Greenland.
In total, more than 3.3 million hectares burned in Canada’s Northwest Territories alone this year—nearly 9 times the long term average—resulting in a charred area bigger than the states of Connecticut and Massachusetts combined. That figure includes the massive Birch Creek Complex, which could end up being the biggest wildfire in modern Canadian history. In July, it spread a smoke plume all the way to Portugal.
In an interview with Canada’s National Post earlier this year, NASA scientist Douglas Morton said, “It’s a major event in the life of the earth system to have a huge set of fires like what you are seeing in Western Canada.”
Box says the real challenge is to rank what fraction of the soot he finds on the Greenland ice is from forest fires, and what is from other sources, like factories. Box says the decline of snow cover in other parts of the Arctic (like Canada) is also exposing more dirt to the air, which can then be more easily transported by the wind. Regardless of their ultimate darkening effect on Greenland, this year’s vast Arctic fires have become a major new source of greenhouse gas emissions from the thawing Arctic. Last year, NASA scientists found “amazing” levels of carbon dioxide and methane emanating from Alaskan permafrost.
Earlier this year, Box made headlines for a strongly worded statement along these lines:

If even a small fraction of Arctic sea floor carbon is released to the atmosphere, we're f'd.


That tweet landed Box in a bit of hot water with his department, which he said now has to approve his media appearances. Still, Box’s sentiment is inspiring millions. His “f’d” quote is serving as the centerpiece of a massive petition (with nearly 2 million signatures at last count) that the activist organization Avaaz will deliver to “national, local, and international leaders” at this month’s global warming rally in New York City on Sept. 21.


Greenhouse gas emissions 

rise at fastest rate for 30 

years

Rise in CO2 concentrations in Earth’s atmosphere causes meteorologists to warn ‘world out of time


9 September, 2014


Surging carbon dioxide levels have pushed greenhouse gases to record highs in the atmosphere, the World Meteorological Organisation (WMO) has said.

Concentrations of carbon dioxide, the major cause of global warming, increased at their fastest rate for 30 years in 2013, despite warnings from the world’s scientists of the need to cut emissions to halt temperature rises.

Experts warned that the world was “running out of time” to reverse rising levels of carbon dioxide (CO2) to tackle climate change.

Data show levels of the gas increased more between 2012 and 2013 than during any other year since 1984, possibly due to less uptake of carbon dioxide by ecosystems such as forests, as well as rising CO2 emissions.

The annual greenhouse gas bulletin from the WMO showed that in 2013 concentrations of CO2 in the atmosphere were 142% of what they were before the Industrial Revolution.

Other potent greenhouse gases have also risen significantly, with concentrations of methane now 253% and nitrous oxide 121% of pre-industrial levels.

Between 1990 and 2013 the warming effect on the planet known as “radiative forcing” due to greenhouse gases such as CO2 rose by more than a third (34%).

The bulletin reveals concentrations of gases in the atmosphere, not emissions – around quarter of which are absorbed by the oceans and a further quarter by ecosystems.

Oceans cushion the increases in carbon dioxide that would otherwise be seen in the atmosphere – but at a cost, with the world’s seas becoming more acidic at a rate not seen for at least 300m years, the WMO said.

WMO secretary-general Michel Jarraud said: “We know without any doubt that our climate is changing and our weather is becoming more extreme due to human activities such as the burning of fossil fuels.

The greenhouse gas bulletin shows that, far from falling, the concentration of carbon dioxide in the atmosphere actually increased last year at the fastest rate for nearly 30 years.

We must reverse this trend by cutting emissions of CO2 and other greenhouse gases across the board. We are running out of time.

Carbon dioxide remains in the atmosphere for many hundreds of years and in the ocean for even longer. Past, present and future CO2 emissions will have a cumulative impact on both global warming and ocean acidification. The laws of physics are non-negotiable.”

Carbon dioxide is responsible for four-fifths of the increase in warming by greenhouse gases, with concentrations in the atmosphere averaging 396 parts per million (ppm) in 2013.

Last year levels increased by 2.9ppm – the largest annual increase seen from 1984 to 2013.

At current rates, annual concentrations will pass the symbolic 400ppm in 2015 or 2016, the WMO said, although that level has already been reached over shorter periods than a year as CO2 levels fluctuate seasonally and regionally.

For the first time, the WMO bulletin includes a section on ocean acidification, caused by the uptake of carbon dioxide into the seas, which can harm the ability of wildlife such as corals, molluscs and some plankton to form shells.

It could also reduce survival, hit development and growth rates and effect physiological functions in wildlife.

Prof Joanna Haigh, co-director of the Grantham Institute for Climate Change and Environment, Imperial College London, said: “Far from a slowdown, the concentration is rising faster than ever – with an inevitable impact on future global temperatures... steps need to be taken now to reduce CO2 emissions.”

Prof Dave Reay, chair in carbon management at the University of Edinburgh, said: “This is the litmus test when it comes to our efforts to reduce emissions and on this evidence we are failing. Of particular concern is the indication that carbon storage in the world’s forests and oceans may be faltering.

So far these ‘carbon sinks’ have been locking away almost half of all the carbon dioxide we emit. If they begin to fail in the face of further warming then our chances of avoiding dangerous climate change become very slim indeed.”


Why We Should Be Paying 

More Attention to Methane





10 September, 2014


Methane. It's the other greenhouse gas - less common and shorter-lived than carbon dioxide, but also a much more potent heat trapper.


If there's one chemical formula most Americans recognize, it's probably CO2. Carbon dioxide. The molecule now thought to be primarily responsible for human-caused climate change.


But carbon dioxide has a much less famous cousin that could also wreak havoc on the climate. Substitute four hydrogens for those two oxygen atoms and you've got methane, CH4, a major component in natural gas.


Methane is the most compact and efficient form of carbon-based fuel, leading to lower carbon emissions than oil or coal when it's burned. That's why people as disparate as President Obama and the billionaire Koch brothers have declared natural gas a critical part of reducing greenhouse gas emissions from electricity production.


There's a down side to methane's simple chemisty, though. It is much more efficient - at least 20 times more - than carbon dioxide at trapping heat in the atmosphere. Methane, itself, only lasts about ten years in the atmosphere, but it breaks down to carbon dioxide, which can stick around for hundreds of years. So, while methane currently makes up less than ten percent of American greenhouse gas emissions, it has a disproportionate impact in terms of warming.


"There's so much we don't know about methane, and it's potential impact is pretty significant."
- Jeff Seewald, WHOI

Just where does all that methane come from? The Environmental Protection Agency’s most recent Inventory of U.S. Greenhouse Gas Emissions and Sinks lists natural gas and petroleum production as the largest source, followed by livestock (think flatulence) and landfills. In all, human activities directly account for more than sixty percent of the methane entering the atmosphere.


Methane, CH4, traps at least twenty times as much heat as carbon dioxide

The remainder comes from natural sources. Methane is produced by bacteria in places where there’s abundant food (a.k.a. carbon, usually from dead plants or animals) but no oxygen. The mud under wetlands and beneath the seafloor are two examples.


But the line between natural and human-caused methane emissions is becoming fuzzy, according to Sue Natali, an assistant scientist at Woods Hole Research Center.


Natali is particularly concerned about the prospect of large quantities of methane being released from Arctic permafrost as it thaws, due to human-caused climate change. Under current emissions scenarios, scientists expect half of surface permafrost to thaw this century.


That previously permanently frozen soil is extremely carbon-rich. It’s estimated to hold between 1,400 and 1,700 gigatons of carbon – nearly twice as much as is currently found in the atmosphere. Some of that is in the form of methane that could be released as permafrost thaws.


The bigger concern, though, is that rising temperatures will enable methane-producing bacteria to ramp up, and all that carbon will provide ample food. That could lead to an enormous infusion of methane into the atmosphere, which would intensify warming, which would lead to more thawing, which would … you get the idea.


Methane, CH4, traps at least twenty times as much heat as carbon dioxide.
Scientists use the term positive feedback,” says Natali, “We mean positive, not that it’s good, but that it’s an amplification of climate warming.”


The recent discovery of three large craters in Siberia that appear to have been caused by a build-up of methane in thawing permafrost has raised the specter of impacts completely unforeseen by scientists.


There’s also been concern that the amount of methane seeping out of the seafloor is increasing due to warming. One climate scientist responded notably to an announcement by Stokholm University scientists that they were finding unexpectedly high levels of methane bubbling up from the seafloor:


If even a small fraction of Arctic sea floor carbon is released to the atmosphere, we’re f’d,” Jason Box tweeted.


But Carolyn Ruppel, head of the Gas Hydrates Program at the U.S.G.S., says this could be a false alarm. Her group recently documented hundreds of methane seeps off the east coast of the U.S. Based on their findings, Ruppel says that there could be thousands more methane seeps that we haven’t discovered yet – not because they’re new; we just haven’t looked before.


That’s not to say that rising temperatures couldn’t increase the amount of methane coming from the sea floor. Warmer waters could thaw frozen pools of methane and increase bacterial production, as well. But Ruppel says most of that would be absorbed by the water before it had a chance reach the surface. To back that up, she points to studies that have found no increase in atmospheric methane levels above locations where methane is bubbling up from the sea floor.


Still, Ruppel says methane deserves more attention than it’s been getting. Natali and Jeff Seewald, a senior scientist in the Department of Marine Chemistry and Geochemistry at Woods Hole Oceanographic Instituion, agree.


"There's so much we don't know about methane and it's potential impact is pretty significant," says Seewald. "Considering it's potential, I think it does deserve significant attention."


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