Thursday, November 15, 2012

Arctic methane: Why the sea ice matters



Arctic methane: Why the sea ice matters 
a new film by Envisionation.co.uk
Interviews with:
James Hansen - NASA
Natalia Shakhova - IARC
Peter Wadhams - Cambridge University, UK
David Wasdell - Apollo-Gaia Project



Arctic Methane: Why The Sea Ice Matters

James Hansen: If it begins to allow the Arctic Ocean to warm up and warm the ocean floor, then we'll begin to release methane [from] hydrates, and if we let that happen, that's a potential tipping points that we don't want to pass. There are now observations that methane is beginning to be released by both melting tundra on the land and bubbling up in the Arctic Ocean, indicating some warming of the Arctic Ocean.

Natalia Shakhova: The total amount of methane in the current atmosphere is about 5 Gt. The amount of carbon preserved in the form of methane in the East Siberian Arctic Shelf is ~ from hundreds to thousands Gt. What divides this methane from the atmosphere is a very shallow water column and a weakening permafrost, which is losing its ability to serve as a seal. This area is very seismically and tectonically active and there was some investigation that the tectonic activity is increasing.

Peter Wadhams: At the rate we're going, it will bring us to an ice-free Arctic in about four years time. [The Arctic Ocean] now warms up to about 5 degrees [5°C or 41°F, i.e.] enough to start warming up the seabed. The seabed at the moment is frozen, but it's now starting to melt. That's allowing a lot of methane which is trapped under the permafrost to be released. That's a large boost to global warming, because methane is an extremely powerful climatically-active gas. 

David Wasdell: The warm water from the surface is now being mixed down to those areas that it never reached when the whole area was covered in sea ice. As soon as the area is open water, you have a process of heating that goes right down to those clathrate deposits on the seabed. The more the methane is released into the atmosphere, the faster the heating goes. It's probably the greatest threat we face, as a planet. We're already in a mass extinction event.

Did Sandy trigger major earthquakes off Vancouver?

The NASA image below gives an impression of the strength of hurricane Sandy, as it approached the U.S. coast on October 28, 2012. 

Image produced with data from a radar scatterometer on the Indian Space Research Organization’s (ISRO) Oceansat-2,
showing the strength and direction of Sandy’s ocean surface winds on October 28, 2012.

This animation was created by Alex Hutko, a seismologist at the Incorporated Research Institutions for Seismology (IRIS) in Seattle. It shows how seismic stations lit up as hurricane Sandy continued its path.

The images below are screenshots from the animation, showing how three eathquakes hit the coast off British Columbia in Canada, coinciding with large tremors caused by Sandy. A 7.7 magnitude earthquake (image below) hit the coast off Vancouver on October 28, 2012, at around 2:00 EDT. The USGS later upgraded the earthuake to magnitude 7.8 and gave the time as 3:04 UTC.
 
 
A 6.3 earthquake below hit the area the same day (October 28, 2012) at 17:00 EDT (USGS: 18:54 UTC).
 
 
A 6.2 earthquake (image below) followed on October 30, 2012.
 
 
The USGS image below gives further time and location details of these earthquakes using UTC time. 
 
 
There were more earthquakes than that. At the USGS site, I counted 90 further earthquakes in the area with a magnitude of at least 4 that occurred within days of the first earthquake.
 
Paul Beckwith, regular contributor to this blog, gives the following comments on the question whether Sandy was the trigger for major earthquakes off Vancouver.
“Sandy was a massive storm, packing an enormous amount of energy. According to Jeff Master's Wunderground blog, she carried the energy equivalent of five Hiroshima sized nuclear bombs.
 
As she approached the eastern seaboard of the United States she was detected on the seismic stations in the U.S. As she moved her large size (tropical storm winds within a 900 mile diameter) and extremely low pressure center (940 mb usually indicative of Category 3 or even 4 magnitude hurricanes), she sucked enormous quantities of ocean water upward.
 
Clearly, this adds tremendous stresses onto the earths crust and pushes it downward; this was reflected in the seismic stations. The animation of her progress shows the ground stresses across North America between October 14th and November 1st. On her northward jaunt up the eastern coast the seismic strain lit up to a peak and there was a 7.8 magnitude earthquake (Oct 28th, 3:04 UTC) off Vancouver, as shown in the first image.
 
As she continued northward and just before her extremely unusual left turn (due to extreme waviness of Rossby wave jet streams leading to continental low and northward tilted blocking high), there was another maximum of red seismic activity and a 6.3 magnitude aftershock (October 28, 18:54 UTC).
 
Then she turned left and as she crossed the coastline just south of NYC there was a second large aftershock of 6.2 magnitude (October 30, 2:38 UTC). Again, this aftershock coincided with large seismic activity indicated in red on the east coast.
 
Coincidence? I think not. Stress on one side of a continental plate (North American plate in this case) can deflect the plate downward locally and cause it to bow up or down afar, i.e. on the other side of the plate of the west coast). The precise coincidence of the timing for the main quake and the 2 aftershocks with peaks of seismic activity on the eastern coast seems to match too closely to be a mere coincidence, but more study is required.”

In conclusion, there is a danger that storms and cyclones trigger submarine earthquakes, which can in turn cause shockwaves and landslides over a wide area, destabilizing hydrates and triggering massive releases of methane in the process. As the sea ice disappears, the Arctic Ocean increasingly features open waters which are more prone to cyclones.

Wednesday, November 14, 2012

Arctic Sea Ice set to collapse in 2015

The image below depicts Arctic sea ice volume as calculated by PIOMAS (the Pan-Arctic Ice Ocean Modeling and Assimilation System at the Polar Science Center

Total Arctic sea ice volume from PIOMAS showing the volume of the mean annual cycle.

Below, the average monthly volume data over the years with exponential trends added by Wipneus, incorporating the data for November 2012. 
In November 2012, the average Arctic sea ice thickness over ice-covered regions fell below one meter, as illustrated by the image below. 
Average Arctic sea ice thickness over the ice-covered regions from PIOMAS for a selection of years.
The average thickness is calculated for the PIOMAS domain by only including locations where ice is thicker than .15 m
As the sea ice gets thinner, the risk increases that the ice will break up. More open water makes the Arctic Ocean more prone to storms and associated feedbacks that can be expected to speed up such break up. Furthermore, they can push much of the ice into the Atlantic Ocean, leaving little ice in the Arctic Ocean to reflect sunlight back into space and to act as a buffer when temperatures start rising again the following year. For more on such feedbacks, see the post Diagram of Doom

Professor Peter Wadhams warns in an article in Scientific American that the rate at which summer melting is outstripping accumulation of new ice in winter makes the entire ice cover likely to collapse by 2015. Less ice means that less sunlight will be reflected back into space; as a result, warming in the Arctic will accelerate dramatically. Because a third of the Arctic Ocean is composed of shallow shelf seas, surface warming will extend to the seabed, melt offshore permafrost and trigger the release of methane, which has a much greater greenhouse warming effect than CO2. A Russian-U.S. expedition led by Igor Semiletov has recently observed more than 200 sites off the coast of Siberia where methane is welling up from the seabed. Atmospheric measurements also show that methane levels are rising, most likely largely from Arctic emissions. To avoid the consequences of a collapse of summer ice, we need to bring back the ice we have lost. That will require more than merely slowing the pace of warming—we need to reverse it, Professor Wadhams adds. 

Wednesday, November 7, 2012

President Obama addresses climate change in acceptance speech



President Obama addresses climate change in acceptance speech

Dorsi Diaz

By Dorsi Diaz

In a move giving hope to environmentalists, climatologists, scientists and humanity, President Obama mentioned climate change in his acceptance speech last night after winning his bid for re-election.

Despite all the threats that America faces, Obama zeroed in on climate change.
“We want our children to live in an America that isn't burdened by debt, that isn't weakened by inequality, that isn't threatened by the destructive power of a warming planet.”
Although climate change was not mentioned once in the candidate’s debates between Romney and Obama, clearly our warming climate is on the President’s mind.

After Hurricane Sandy hit the East Coast and cost lives and billions of dollars in damage, the subject of climate change has repeatedly been brought up, and the tide of public opinion on global warming has shifted – with over 70% of the U.S. now believing that climate change is real.

Days before the election and in the aftermath of Hurricane Sandy, the subject of climate change also shifted the thoughts of some on who to vote for in the election.

Mayor Michael R. Bloomberg of New York decided to vote for Obama saying he had decided that Mr. Obama was the “better candidate to tackle the global climate change, which he believes might have contributed to the violent storm.”
Our climate is changing”, Bloomberg wrote. “And while the increase in extreme weather we have experienced in New York City and around the world may or may not be the result of it, the risk that it may be - given the devastation it is wreaking - should be enough to compel all elected leaders to take immediate action.”
Although the debates featured both candidates speaking of drilling for oil, it looks like the President’s agenda will be to continue focusing on clean energy, sustainability and green issues. Although there were some failed attempts to implement Obama's policies in his first term, we can be sure to expect the continuation of working towards a more sustainable future in the next 4 years.

When elected in 2008, President Obama had high hopes for addressing climate change, but with the focus then on saving the faltering economy, bailing out the banks and a corrupted Wall Street system, attention was diverted away from the subject. Despite the threat of an economic meltdown when Obama first took office, there was still a major push towards creating green companies, researching alternative energy sources and a focus on green energy jobs.

Although the President faced opposition from many Republican leaders who didn't believe in climate change, the tide of public opinion and the necessity to address climate change has many people concerned. With extreme weather on the rise and costing lives and billions of dollars in damage, people are also waking up to the growing threat of a catastrophic release of methane gas from the rapidly thawing Arctic.

Methane gas is many times more powerful than carbon dioxide, and has the ability to send the Earth into runaway and/or abrupt climate change.

In a recent plea to world leaders to address the growing threat of climate change: Why Arctic Sea Ice Matters To You and Me (pdf), John Nissen of AMEG (Arctic Methane Emergency Group) didn't mince words when he put this out on the table for world leaders to ponder:
“We are toppling over the cliff edge. Collapse of sea ice could be even more dramatic next year. We face an almost irreversible transition to an ice-free Arctic. Only immediate and drastic action to cool the Arctic can stop it now. The consequences of further meltdown would be dire for you and all your citizens. The weather extremes we've witnessed this year could get far worse, leading to widespread crop failures and an ever deepening food security crisis affecting every country in the world.”
Written in September of 2012, before Hurricane Sandy hit, Nissen's plea seems to hold many truths as we stand witness to the devastating damage from an unprecedented storm dubbed “Frankenstorm”.

With a need to put more pressure on global leaders to address the growing threat of climate change, more action is needed to act fast and act quickly. Climatologists and scientists say the window of opportunity is rapidly closing.

With Obama's words on climate change during his acceptance speech, a tiny flicker of hope has been stirred that maybe, just maybe, something can be done to avert a climate change mega-disaster.

And with the Pentagon stating that climate change is the number #1 threat to national security, perhaps a global consensus surpassing partisanship can take place – with saving humanity as the ultimate goal.

After all, the economy won’t matter if there are no people left to have jobs.


From an article posted earlier at Examiner.com - posted with the author's permission