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Climate May Be Less Sensitive To CO2 Than Previously Thought
a_hanso writes "A new study suggests that the effects of rising levels of carbon dioxide on temperature may be less significant than previously thought. 'The new models predict that given a doubling in CO2 levels from pre-industrial levels, the Earth's surface temperatures will rise by 1.7 to 2.6 degrees C. That is a much tighter range than suggested by the Intergovernmental Panel on Climate Change's 2007 report, which suggested a rise of between 2 to 4.5 degrees C."
...let the rational, even-handed and emotionally detached debate begin!
We should be switching to nuclear anyway, it's not about global warming, it's about the eventuality of the end of the age of oil. It will happen so it's better to be thinking about it now.
You can't handle the truth.
It's also a 66% confidence projection using a new climate model that has undergone peer review but probably not much other discussion in the community. It's interesting, but hardly definitive.
There are climate deniers, who think nothing should be done, and then there are economy deniers, who don't actually believe that their policies have economic cost (and may in fact praise them for "creating jobs").
If you're not one of the irrational extremists, you have to deal with them both (and will probably be called one when dealing with the other). It kinda sucks.
The World Wide Web is dying. Soon, we shall have only the Internet.
There are hundreds of things changing the temperature contantly and it's very hard to isolate the changes CO2 caused.
Like I keep repeating - there's only 40 years of oil left.
While I find your argument of proof by repetitive assertion convincing, I think that 20 years ago there was only 30 years oil left. In another 40 years it may have reach 80 years left. Maybe there's more people repeating the opposite to you and it's actually driving the oil supplies upwards?
It's an interesting piece of work. There are two issues to bear in mind:
- They are calculating climate sensitivity at the last glacial maximum. Climate sensitivity varies with temperature, so the sensitivity now may not be the same as the sensitivity at the LGM. It is entirely possible that both this study, and all the studies which put a higher value on current sensitivity, are both correct.
- Even their most likely value of 2.3C only gives us about 15 years extra breathing space to sort out our emissions.
- The UVic model they use is rather simplistic, and I'm not sure it reproduces 20thC climate that well. It would be interesting to see this work repeated with a model ensemble.
Only good can come?
Are you sure of that?
Because I can see many things wrong with your statement.
Many bad and not so good things can come from Reducing CO2.
Cars cost more, jobs pay less, food and gas cost more.
Some businesses are getting seriously hurt. (Try making cement in California)
I can understand 5 year olds thinking that all is good and nice. You though are presumably an adult.
try some critical thinking.
Are the benefits realized by these reductions worth the cost?
I do not know. I think that further reductions may in fact not be worth the cost.
But of this I am sure.
Not only good comes from the reduction of CO2.
Why is it so hard to only have politicians for a few years, then have them go away?
What if a reduction in CO2 means a reduction in consumption of fossil fuels, and therefore a significant cost reduction, especially if oil-prices go up? What exactly will prevent another (possibly lasting) oil crisis? The oil is slowly but surely running dry, and certain (oil-dependent) countries are ready to fight over oil or use it as a weapon (just look at Iran; they are currently threatening to cut off the Strait of Hormuz, thus blocking not just their own but many other Middle-east countries oil export). It may be cheaper to rely on oil and gas at this very moment, but other energy sources, may well become cheaper in the (very near) future.
Now this one really does require a citation. And oil doesn't just have to be pumped in the traditional manner.
Unfortunately the assertion that there is x numbers of oil left is based on a number of observations. So where to start.. We can start with the observation that for any given well or field supply/production follows a bell curve. Production increases until it hits a peak and then declines. Advancing technologies gives the bell curve a long tail but peak production is only hit once. If you add the curves for each well it will create a curve for each field. Add each field together and you get a curve for each region. Keep going and you will get a curve for each continent. At some point there will be a curve for the earth as a whole.
.5 trillion to as much as 2 trillion. Personally I think 2 trillion is wishful thinking as we have been looking for oil for a century now.
Now that's not all of it of course. There are undiscovered reserves. For any given region there is a bell curve for discovery. We discover more and more and then less and less. The discovery curve will tend to peak about 10 (give or take 5 year) before the supply curve. As an example we can look at the continental U.S. In 1956 Hubbert predicted peak oil for the continental in the United States to occur around 1970. He was correct. In the 30 years since continental oil production peaked, oil production has been on a gradual decline. Matching predictions made over 50 years ago. Note, the continental U.S. is just that it does not include Alaska and off shore oil but is an example of how peak production occurs in a given area and follows peak discovery.
Of course we need to know more to make an estimate for peak oil for the world. We need to know how much oil we've already used and how much we know about that is left and how much we don't know about that is left. For the first part we know we've used about 1 trillion barrels of oil so far. For the second part we know a range that geologist use. P10, P50 and P90 number provide 10%, 50%, and 90% probabilities of reserves. We use P90 numbers to denote proven reserves meaning there is a 90% chance that it is how much we have left. According to the oil industry proven reserves are between 1.1 and 1.3 trillion barrels in 2007. Adjusting for the last 4 years and that proven reserves are 90% sure not 100% lets just call it an even 1 trillion.
Ok so 1 trillion used and 1 trillion in proven reserves but of course there's the undiscovered oil too. Now we have to rely on speculation but we can take some things into consideration. For instance we have seen peak discovery in some areas so we can extrapolate what is left to be discovered by looking at the curves. We can further argue that larger fields are easier to find than smaller ones in much the same way we could say there are still undiscovered islands in the ocean but it is unlikely there are undiscovered continents. There is a lot of speculation when it comes to estimating what we haven't discovered. Some based on optimistic numbers and some based on pessimistic ones. It ranges from
But Ok, I'll give 2 trillion barrels of undiscovered oil. So now we can say total oil is around 4 trillion. We've used 1 trillion and have 3 trillion left in proven and undiscovered oil. The world uses ~80 million barrels/day or about 30 billion a year. If demand stays constant (there is no reason to believe it will, everything indicates it will rise) We can safely say we will use 1 trillion barrels in 33 years. So in 33 years we will have used 2 trillion bbls total and have 2 trillion left. This is the optimistic number for peak oil. Now for peak liquid oil (excluding tar sands and such) many estimates for peak liquid oil are put at sometime in the last 3 years. Probably around 2008. That year when gas in the U.S. went over $4/gallon and then dropped under $2 as the economy crashed and demand went down.
When supply peaks demand will be constr
Oil is always going to be available. Whether or not it will be available at prices that allow for stable economies around the globe is the question. If oil hits, for example, $500 / gallon and thus gasoline prices are $15 / gallon "business as usual" (aka the economy) has big issues. Big issues.
1) China's and India's economies have been expanding at an insane pace in the last 10 years. More people in those countries drive cars now than every before. The demand has continually been increasing.
And the oil exporters in the Middle East, understanding they have a limited supply of oil in the ground are NOT increasing output much, if at all. The US / Canada in a mad attempt to keep up has been utilizing every drilling rig available for the past 5 years and we are just barely keeping pace with output reductions from the older fields.
So, if Chindia keeps munching on the fossil fuels and we keep doing the same AND production INCREASES don't keep up, you have, wait for it, Peak Oil.
2) Developed nations (most notably the U.S. and Canada) have politically decided that oil is "dirty" and entire industries have been prevented from expanded production of oil in these 2 nations (which have vast tracks of land, full of oil), this is to say nothing of the rest of the world, which seemed quite content to just let the monopoly OPEC exist and just deal with them.
Well, aside from the implication that the Sierra Club and Greenpeace are running things (you might want to tell them), we are, as I mentioned, punching holes through our 'vast tracts of land' and not keeping up with the big increases. Hint - go look up the geology of future North American 'conventional' oil reserves. The USGS keeps dropping that number every year. And a lot of geologists think that the official USGS figures are still overstated.
You have an funny definition of 'monopoly' - Oil is probably the most decentralized power supply on the planet. OPEC / Brazil / China / US / USSR / whateverstan / Non OPEC Middle East - it's everywhere. We've just sucked out the easy stuff.
Now it gets as Johnny Depp would say, complicated.
Faster! Faster! Faster would be better!
Here is an interview with the author of the paper: http://newscience.planet3.org/2011/11/24/interview-with-nathan-urban-on-his-new-paper-climate-sensitivity-estimated-from-temperature-reconstructions-of-the-last-glacial-maximum/
Q. It’s a little funny, to me, that your paper was receiving such positive comments from skeptics while many of those same skeptics also support claims by Richard Lindzen and Roy Spencer purporting to find an essentially insensitive (~1C or less) or self-stabilizing climate. Does your paper support such incredibly low values for ECS?
Our analysis found a lower bound of 1.35 C for climate sensitivity (less than 5% probability of being below this bound). We tried a range of statistical and physical assumptions, and found sensitivities as low as 1.15 C, and as high as 4.65 C (if we analyze the land data). I don’t think sensitivities lower than our bound are consistent with either our study or paleoclimatic evidence in general.
Q: Any other thoughts on the skeptics’ reception of your paper?
One blog did surprise me. World Climate Report doctored our paper’s main figure when reporting on our study. This manipulated version of our figure was copied widely on other blogs. They deleted the data and legends for the land and ocean estimates of climate sensitivity, and presented only our combined land+ocean curve: