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Comment Re:Evidence of the Great Filter? (Score 2) 365

We can get some idea of the likelihood of some stages by looking at how long in took for them to occur on earth. For instance, it took about 1 billion years for life to form on earth, but after that it took an additional 3 billion years before the Cambrian Explosion, where we saw significant diversification of complicated lifeforms. That 3 billion year gap allows time for all sorts of global cataclysms--we had one that nearly wiped out life during the snowball earth. After the Cambrian Explosion it took a mere half billion years to reach technological intelligence.

But it's very dangerous to simply extrapolate from a single data point (Earth) - there are quite a few environmental elements that could massively influence those timescales - for example the early sun was quite a bit fainter than it currently is, so those 3 billion years might just have been necessary to reach some kind of tipping point favouring the development of complex multicellular life, on another planet under slightly different conditions, this might take just a fraction of that time (or it might never reach that tipping point) - similarly, it took about half a billion years to reach technological intelligence, but that may just be due to particular circumstances on our world, the timing, place and cause of the different mass extinctions, the conditions occuring which permitted the different precursor steps that may be required for a technological civilisation to occur (things like the move from water to land, the increase in available energy afforded by endothermy, ...)

Comment Re: They're called trees. (Score 4, Informative) 128

The sun is _slowly_ brightening - this is happening on timescales of tens to hundreds of millions of years. The fact that CO2 was significantly higher tens or hundreds of millions of years ago is not super-relevant to today's conditions, but it helped keep temperatures bearable in the distant past, when the sun was fainter. We are adding CO2 at a rate that is essentially instantaneous compared to the effects of this solar evolution, they are even still extremely quick on the much shorter (tens of thousands of years) timescales of the Milankovitch-cycles (which are the orbital cycles which are the underlying cause of our glacial-interglacial variation in the past few million years)

What interests us at this time is what we are doing to our atmosphere over a period of tens to hundreds of years, and what effect that has on timescales of tens, hundreds and thousands of years - even if we humans stop all of our CO2 emissions (except breathing of course), the increased concentration versus "before" will be considerable thousands of years into the future, as will the effects of that increase on climate.

So stating "still at the extreme lower end of historic levels" is technically correct, but practically misleading, as it suggests there's nothing wrong with CO2-levels.

Comment Re:Neutrino Detection? (Score 2) 85

Yes, neutrinos have been detected in this type of detector for many, many years - in 1987 the neutrino's from SN1987A were detected by several of these detectors.


For the actual papers, consult the "sources" listing at the end of each Wikipedia entry.

Comment Re:Yes, because car exhaust warms the earth's cent (Score 1) 130

Keep drinking the cool-aid, their latest report doesn't "admit" what you claim here, not by a long shot - it actually states that they're even more certain now that most of the recent warming is caused by Anthropogenic CO2. What has happened is that the right wing climate denialosphere are spinning like they've never spun before, trying to deform and cherry-pick statements from the report into what they want it to say... And you're clearly lapping it up uncritically, probably because it reinforces what you *want* to hear...

And Dr. Richard Lindzen may be a "climate scientist" (I would certainly dispute the "top" prefix....), but he doesn't walk the walk like he talks the talk - he's always up for yapping away in the media about not trusting models & stuff, but when he actually goes about publishing articles, those recognise the reality of AGW... At this point, he's little more than a paid shill for the Oil industry...

Comment Re:All the observed data is perfectly normal (Score 2) 130

What Steve Goddard "forgets" to mention is that it's actually only the Antarctic sea ice that is growing, while the land-ice there is melting away ever faster...

And the 67% more ice in 2013 compared to 2012 still puts 2013 in 6th lowest position for arctic ice-extent in the observational record, curiously together with 2007-2008-2009-2010-2011-2012) - so it is lower than *any* observed ice-extent prior to 2007... Doing better than the single worst year on record is not proof that nothing's wrong, it's just proof of the fact that there are significant annual fluctuations in ice-extent, primarily due to short-term weather.

Average thickness and ice-volume in the Arctic are actually far more relevant measurements (as unlike "extent", they measure the *amount* of ice, not how thinly it's spread out) and those have been dropping almost without fail year after year after year...

Comment Re:Is the end nigh again? (Score 2) 130

Antarctic *sea ice* is "growing" (most of it actually melts away each summer) - Antarctic land ice is shrinking, in part because it's melting away and in part because it's more quickly flowing to the sea, where it contributes to the sea ice growth.

Sea ice growth around Antarctica is a *consequence* of global warming, not proof against it...

And the situation is profoundly different for the Antarctic then for the Arctic, due precisely to the completely different land/sea configurations at both poles...

You are in a maze of UUCP connections, all alike.