It is not a guess. It's what scientists who have studied the matter say. And I was being generous. Scientists say CO2 levels probably have to get down around 250 ppm for a new glaciation to commence.
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Again the Central Greenland ice core graph that AC threw at me above. Tell me how that relates to global temperatures. You need to broaden your view.
Perhaps you could point out a specific ice age where CO2 was 7000 ppm. I've never heard of it. There were ice ages when CO2 was as high or somewhat higher than it is now but the configuration of the continents was entirely different and the Sun was not quite as strong as it is now.
Really?!!! One measurement of a Central Greenland ice core is going to tell us all we need to know about temperatures. I don't think so.
By Daniel Griffin and Kevin J. Anchukaitis, published in Geophysical Research Letters, Volume 41, Issue 24, December 2014
For the past three years (2012–2014), California has experienced the most severe drought conditions in its last century. But how unusual is this event? Here we use two paleoclimate reconstructions of drought and precipitation for Central and Southern California to place this current event in the context of the last millennium. We demonstrate that while 3 year periods of persistent below-average soil moisture are not uncommon, the current event is the most severe drought in the last 1200 years, with single year (2014) and accumulated moisture deficits worse than any previous continuous span of dry years. Tree ring chronologies extended through the 2014 growing season reveal that precipitation during the drought has been anomalously low but not outside the range of natural variability. The current California drought is exceptionally severe in the context of at least the last millennium and is driven by reduced though not unprecedented precipitation and record high temperatures.
I live a bit south of you in the Willamette Valley and I remember that cold stretch back in December. It's been a strange winter. No snow in the Cascades where there should be 4 feet or more of snow pack by now.
Those guys attacking AGW need to get out more.
The issue isn't so much the proper temperature but the rate at which temperature is changing. The current rate of change is around 2 orders of magnitude greater than it was coming out of the last ice age.
These stories are tiring as there is no chance for "settled science fact" in climate change.
All of these estimates are based on elaborate math models and yet the Earth's long term climate ON ITS OWN, has swung widely over recorded history.
And from the geologic history, we know we will again go into another ice age based on the history of the change in the Earth-Sun orbit & precession changes on a regular 110,000 year cycle. And without human intervention, the ice age ends.
There is no chance of another glacial period occurring until CO2 levels drop well below 300 ppm again.
yeah why don't you go tax a volcano because just one small eruption is millions of times larger in volume of CO than the entire world production of hydrocarbon fuels... I AM AN IDIOT..
FTFY. Human emissions of CO2 are about 100 times greater than volcanic emissions.
You can't lay California's lack of rainfall at warming's feet but you can say the drought was exacerbated by record high temperatures that caused the soil to dry out more than previous droughts.
Wasn't it supposed to raising 2 degrees/decade yy now ?
Aren't the poles supposed to be ice free by now ?
Isn't Florida supposed to be underwater ?
Isn't the entire east coast supposed to be rubble from super hurricanes ?
Dustbowls that would make the 1930s look like nothing ?
Really enough of the chicken little.
Instead of listening to hyperbole why don't you peruse the actual scientific literature on those subjects? You won't find any of that in the time frames you contemplate.
This year we have seen record low temperatures across the north american continent that have pushed our country to the limits.
While the eastern third of the country has been cold the western third of the country has seen record high temperatures. In fact the eastern third of North America is about the only place on the Earth that's had below average temperatures this winter.
If you tax fossil fuels you also tax any imports for the fossil fuels that went into making and delivering them. Poorer countries don't use enough fossil fuels to matter much right now.
Considering that Milankovitch cycles show the earth's recent temperature swings are significantly more than 1.5 degrees WITHOUT impact from man, this seems a bit nutty. Global climate change has been happening for a long time before man started burning fossil fuels. Sure it sucks for some, but then again, it will be sweet for some people who get benefits from such a change. Life goes on, just like it has in the past ice ages, despite 1000 metre thick glaciers covering much of Europe and N. America.
Earth is not a static closed system folks... It changes shitloads more all by itself then any amount attributed to by even the most generous of climate analysts. Get used to it. Buy a vineyard in England.
The difference in temperature between the depths of the ice age and now is about 5 degrees C but that rise in temperature was spread out over 10,000-15,000 years (5 degrees/10,000 = 0.0005 degrees/year). The current temperate change is between 0.01 and 0.02 degrees/year, two orders of magnitude greater than when the ice age ended. The problem isn't so much that temperature is changing but that it's changing so fast. The greater the rate of temperature change the harder adaption will be for both human and natural systems. The Earth will survive and life will survive the current warming but there will mass extinctions and that may well include civilization as we now know it.
And if we hadn't invaded Iraq in the first place and destabilized it ISIS might not exist at all.