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Arctic Sea Ice Hits Record Low Extent
mdsolar writes "Arctic sea ice has hit a record low extent for the period of satellite observation. Further, this record has been set in August when the minimum annual sea ice extent (and the prior record) has always come in September. Further still, the ice is still retreating as rapidly as it was in June and July when normally the decrease of sea ice extent slows in August. It is thus possible the the final minimum sea ice extend for 2012 will be seen in October rather than September as has always occurred in the past. More than one monitoring effort agree on the existence of a new record."
Here's a paper about Arctic sea ice for the past 47 million years: "History of sea ice in the Arctic" (Polyak, et. al. 2010). It may have some of the information you seek. Here's the abstract:
Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This information can be provided by proxy records from the Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO2 after the Paleocene–Eocene Thermal Optimum, and consistently covered at least part of the Arctic Ocean for no less than the last 13–14 million years. Ice was apparently most wide-spread during the last 2–3 million years, in accordance with Earth’s overall cooler climate. Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter-term (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities. 2010 Elsevier Ltd. All rights reserved
Yes, That reflectiveness of the white ice as compared to the darkness of the deep blue sea is known as its albedo .
Being I first learned solid state linear design on germanium transistors, I am well aware of something we called "thermal runaway", in which the transistor would bias itself on more and more as it got hotter, yet being biased on was what was making it hot. The hotter it got, the more current it passed. Thermal runaway.
The result was a fused transistor.
The mathematics of thermal runaway on those old designs is nearly identical to the albedo-loss calculations of our ice caps. I find it a frightening scenario, as I can't simply change out the planet as easily as I can replace a fused transistor.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
I live in northern canada. 57th parallel. The winters have been getting warmer and warmer over the last 20 years. Rarely see -50C now, last winter coldest was -36C.
The thing is, canada is a nation of lakes and rivers. The water is getting warmer. Coupled with all the large scale hydro electric projects, the temperature of the land is getting warmer over the course of the year. The tipping point you are referring to, is all the peat bog. Its burning in forest fires during the summer, but the big problem will be all the methane it is off gassing. Most of the north is frozen bog..... this will be an interesting experiment.
And in this economy, climate change isn't even anywhere on the radar. It's a rich people's problem.
A revenue neutral carbon tax can be used to stimulate the economy, as it has done over the past 10 years in 1/5th of the US economy (relative to the rest of the US economy), and in Germany, which sustained 3% p.a. growth during a global recession.
/perceived/ as a rich people's problem; however, the shrill cries of economic Armageddon -- ironically by those who decry "alarmism" -- has confounded sane public discussion on the economic benefits of ploughing oil money directly back into pure market-based innovations that save energy.
AGW is
Energy bills have come down in North-Eastern USA for both industry and consumer. It is almost as if Adam's invisible hand can fall captive to tradition, and sometimes needs a little push.
Like all pain, suffering is a signal that something isn't right
Yep, the top 10 feet of the oceans contains as much heat energy as the entire atmosphere.
Slashdot is one of the oldest nerd/tech blogs in existence, before there even was a word for such a thing. For this reason, it's a bit peculiar:
1. Unbelivable as it may seem, the net had a higher share of libertarians before than today. Libertarians often (not always) deny global warming because a) it gives the uncomfortable feeling that strong government action may be needed to address it, and b) they have no problem assuming they're smarter than climate scientists, because they assume they're smarter than everyone anyway.
2. Since it is so old, many slashdot posters have actually had time to become quite rich from their geek skills. Well-off, established people don't want to believe the world is in trouble and that they need to change.
3. There are today a number of tech/geek sites which are arguably more interesting than slashdot. Most have moved on to these. Those who remain are weighted towards the kind of people who don't approve of unnecessary change, i.e. conservatives, who also tend to deny climate science for cultural reasons. (Not inherent reasons, if you ask me climate change is a prime example of unnecessary change).
xkcd is not in the sudoers file. This incident will be reported.