Abrupt climate change is defined by the IPCC as a large-scale change in the climate system that takes place over a few decades or less, persists (or is anticipated to persist) for at least a few decades, and causes substantial disruptions in human and natural systems.
Examples of components susceptible to such abrupt change are clathrate methane release, tropical and boreal forest dieback, disappearance of summer sea ice in the Arctic Ocean, long-term drought and monsoonal circulation.
Deposits of methane clathrates below the sea floor are susceptible to destabilization via ocean warming.
Anthropogenic warming will very likely lead to enhanced methane emissions from both terrestrial and oceanic clathrates.
Above extracted from:
- Intergovenmental Panel on Climate Change (IPCC), AR5 Workgroup 1, Technical Summary
New Finding Shows Climate Change Can Happen in a Geological Instant
The Paleocene/Eocene thermal maximum (PETM) is a climate shift that occurred 55 million years ago.
James Wright, Rutgers University Research News -
Morgan Schaller, James Wright, and the core sample that helped them understand what happened – and how fast it happened – 55 million years ago. |
Following a doubling in carbon dioxide levels, the surface of the ocean turned acidic over a period of weeks or months and global temperatures rose by 5 degrees centigrade – all in the space of about 13 years.
“We’ve shown unequivocally what happens when CO2 increases dramatically – as it is now, and as it did 55 million years ago,” James Wright said.
The film below goes into more detail regarding the current situation.
New Film: Last Hours
The film “Last Hours” describes a science-based climate scenario where a tipping point to runaway climate change is triggered by massive releases of frozen methane. Methane, a powerful greenhouse gas, has already started to percolate into the open seas and atmosphere from methane hydrate deposits beneath melting arctic ice, from the warming northern-hemisphere tundra, and from worldwide continental-shelf undersea methane pools.
“Last Hours” is narrated by Thom Hartmann and directed by Leila Conners. Executive Producers are George DiCaprio and Earl Katz.
For more, also watch some of Thom Hartmann’s interviews.
High Methane Levels persist over Arctic Ocean
High methane levels are prominent over the Arctic Ocean, as illustrated by the image below, covering a period from October 3, 2013, 10:54 am to October 7, 2013, 11:53 pm. The fact that methane has not been present elsewhere in such high concentrations over this period indicates that the methane wasn't carried there by the wind from elsewhere. Also, methane typically appears to move along the same latitude, due to the Coriolis effect.
The image indicates a link between seismic activity and destabilization of methane that is held in sediments under the Arctic Ocean. Methane does show up prominently along the fault line that crosses the Arctic Ocean and extends into Siberia over the Laptev Sea.
The Diagram that IPCC failed to include in AR5
The diagram below shows global warming evolving into accelerated warming in the Arctic. Feedbacks such as albedo changes and methane release speed up this process, triggering abrupt climate change and finally extinction.
The Diagram the IPCC failed to include in AR5 |
Originally posted at the Arctic-news blog
Related posts
- Just do NOT tell them the monster exists
http://arctic-news.blogspot.com/2013/10/just-do-not-tell-them-the-monster-exists.html
- Methane Release caused by Earthquakes
http://arctic-news.blogspot.com/2013/09/methane-release-caused-by-earthquakes.html
- Climate Plan
http://climateplan.blogspot.com