It's not really important whether or not CO2 levels were higher in the distant past; they were, but in many ways the world was different back then. What matters is that life has evolved to suit the planet as it is now and the concern is that life would struggle to adapt to rapid change. 350 ppm is not the point of no return, but the level at which it is LIKELY that dangerous climate change can be avoided.
Sadly, we have exceeded this value and it doesn't look as levels will be coming down anytime soon. As a species, we seem content to take the risk.
There is no "point of no return". That implies that, at 360ppm, we go from "no damage" to "all the damage", or something.
Which is not to say that 400 ppm of CO2 won't cause more damage than 360 ppm. But the same is true of 450 ppm vs 400 ppm. The less we throw the planet's climate systems off balance, the less damage it will cause to other life forms, and to us.
360 was the tipping point. Then it became 400. Now it is 450 ppm CO2. Funny how that tipping point keeps moving to stay ahead of the measured value. Here is a reference claiming 450 ppm is the tipping point.
http://www.dallasnews.com/opinion/latest...
One problem with tipping points is that once they are reached, the climate alarmists must scramble to change their message- and hope their audience has a short memory. For example, now that CO2 concentrations have hit the so called "tipping point" of 400 ppm, the "tipping point" has become a "milestone." I'm not making this up folks. As it turns out, we are not doomed. There is still time to reverse the impending climate catastrophe.
http://research.noaa.gov/News/NewsArchiv...
I think 360.org needs to become 460.org. Don't worry, nobody will notice the change. They will quickly pick up the mantra "We must act now. 460 is the tipping point."
Edit: Here is a gem I just found. Respected astrophysicist Penny Sackett says we have five years to to avoid disasterous global warming. Here is the money quote:
" Asked to explain data that showed the earth had been cooling in recent years, the trained astrophysicist acknowledged air temperatures had levelled during the La Nina weather pattern, now nearing an end."
Of course, she said this in December, 2009, 4 years and 10 months ago. I guess we are all doomed.
http://www.heraldsun.com.au/archive/news...
It is 350.org an organisation started by Bill Mckibben, funded by The Rockefeller institute and various green environmenalist groups, we can see how devious this is the Rockefellers want to get rid of coal, and they know their oil will always be in demand.
It is basically a propaganda site aimed at brainwashing the masses and used by different organisations aiming to further their own causes.
Do not worry CO2 has been ten times higher in the past without damaging the planet, in fact during the Ordovician period we had an ice-age with CO2 at 4,000ppm
It is 350.org, and no that is not a point of no return. If it were, this group would have to close down.
It is also not required to return to 350 ppm, which is itself very unlikely given that CO2 is going to kepp increasing for decades as the developing world develops rather than stay in poverty.
Just another greenie scare tactic.
Joseph Goebbels,
“If you tell a lie big enough and keep repeating it, people will eventually come to believe it. The lie can be maintained only for such time as the State can shield the people from the political, economic and/or military consequences of the lie. It thus becomes vitally important for the State to use all of its powers to repress dissent, for the truth is the mortal enemy of the lie, and thus by extension, the truth is the greatest enemy of the State.”
This is just a method of the greenies to repeat the lie. Hey! This is an official Organization! Wow! They must know something we don't!
Ha! Ha! these saviors of the world are a dime a dozen and all out to scare you with lie after lie after lie.
Ha! Ha! Just look at CR, "You call realists "alarmists," but the only one I see making statements about warming killing all life on the planet is you."
Quote by George Monbiot, a UK Guardian environmental journalist: "...every time someone dies as a result of floods in Bangladesh, an airline executive should be dragged out of his office and drowned."
Wanna another?
Quote by Jill Singer, Australian green and "journalist": "I'm prepared to keep an open mind and propose another stunt for climate sceptics - put your strong views to the test by exposing yourselves to high concentrations of either carbon dioxide or some other colourless, odourless gas - say, carbon monoxide."
Wanna nuther?
Quote by Ingrid Newkirk, a former PETA President: “The extinction of Homo Sapiens would mean survival for millions, if not billions, of Earth-dwelling species. Phasing out the human race will solve every problem on Earth - social and environmental.”
And there are more and they are CR's buddies. Now CR, how does it feel to b e on the losing end of an argument? AGAIN? Ha! Ha! Ha! Ha!
during the ordovician period there was NO LIFE ON EARTH yet .
earths hottest period ( when there was life ) was the 100 million year carboniferous epoch when even the arctic was tropical , atmospheric CO2 was as high as 363 ppm . on 12 21 12 atmospheric CO2 hit 400 ppm . the charlton heston classic Soylent Green is turning out to be eerily accurate as to the events and timeline of how global warming will destroy humanity .
Please consider the following in my critique of 350.org
Global warming is happening
http://www.noaanews.noaa.gov/stories2010...
And we are causing it
http://c1planetsavecom.wpengine.netdna-c...
The ten warmest years in the instrumental record are 2010, 2005, 2009, 2007, 2002, 1998, 2006, 2003, 2013 and 2012.
http://data.giss.nasa.gov/gistemp/graphs...
And I believe that it is reckless to assume that the effects of global warming would be minimal or beneficial.
350.org is an organization that advocates, not only reducing greenhouse gas emissions, but the reduction of carbon dioxide to 350ppm. According to some computer models, if we could and would reduce carbon dioxide to 350ppm, we would supposedly avoid further problems from global warming.
I have two problems with the idea of reducing carbon dioxide to 350ppm/
1. I don't believe that reducing carbon dioxide to 350ppm is even possible, not for hundreds of years. Driving SUVs in reverse and switching wires at coal plants will not cause them to suck carbon dioxide out of the atmosphere.
2. The notion that adding carbon dioxide to the atmosphere is reversible could be used as an excuse to keep burning fossil fuels.
Alph
Kano also ignores the fact that carbon dioxide was 4,000ppm according to proxies from before and after the ice age. Carbon dioxide was lower during the ice age if for no reason other than cold temperatures lead to reduced carbon dioxide.
pasper
It did reach the tipping point. Through most of Earth's history, there wasn't ice at the poles. I would call that reaching the tipping point.
You call realists "alarmists," but the only one I see making statements about warming killing all life on the planet is you.
Besides, I thought that parking SUVs was what was supposed to kill all life on the planet.
Anonymous
Actually, there was life then
http://pubs.usgs.gov/gip/fossils/fig15.g...
Nature likes numbers that are divisible by 5.
try 350.org
it is a target. you need to define what no return means.
again kano is misleading by not mentioning the sun was weaker millions of years ago. the earth did not have 7billion people and expensive infrastructure.
