(there was a X1 or X2 solar flare in last day.)

My sister sent me a thread from some other site on dicussions of climate change and CO2 levels. Someone had said that we might get 450 ppm in 15 years, 550 ppm in 22 years, and 650 ppm in 27 years, and a really catastrophic 1000 ppm in 35 years.
I replied below:

hmm, interesting that those really high rates are so soon. But, I suspect that this is with some exponential increase in rate, rather than taking a linear rate from today. I'm not checking and am liable to be wrong, but I think we have been doing about 2 ppm/yr and we are close to 390. So, would take 30 years, not 15 to get to 450. But, yes, the rate of increase in CO2 would be accelerating, so would be less than 30 years.

OK, now I'm checking: http://www.esrl.noaa.gov/gmd/ccgg/trends/

It is 2 ppm/year and the trend has been pretty linear for last 5 years. No way are we getting to 1000 ppm in 35 years. It seems like the last person may have been just using a high rate of increase in emissions in 1 year, put that all into the atmosphere (which the link is saying did not happen), and is probably making some exponential curve for emissions.

While the rest of the world is indeed probably laughing at USA (if it was not actually so sad), there is some tendency for reporters and some scientists working close to the field to exaggerate or get it wrong. That is an opinion of mine, not a fact: the graph on the link is a fact. This is, again in my opinion, also damaging (like Santorum). I went to a presentation by the USA Geography representatives to Copenhagen a couple of years ago and they showed graphs. I recall the worst case was near 800 or 1000 by end of century, and that we were running above the worst case curve.

There is some limit on the rate of increase in fossil fuels that we can find to burn. I'm always a little disturbed when we find more; Alberta tar sands become economic, so more produced, huge finds offshore Brazil, etc etc. Even the recent fracking techniques for USA natural gas are a bad thing for climate long term. While per energy unit natural gas may put out half (?) the CO2 than coal, I think we will still burn the coal.

I've been thinking for years: "if we find it, we will burn it"

What is missing from the discussion is methane. Methane could be released on a massive scale, from the sea floor (methane hydrate...sort of frozen methane), permafrost, etc. Scientists think something like this might have happened 50 or 55 million years ago, at the peak of the Greenhouse world.

The below is mainly for if you post this:
HW and I each work on aspects of this. She works on sea floor seeps and hydrate, and I work on the sedimentary record of past climates using sub-bottom acoustics (seismic reflection): I'm working on Ross Sea Antarctica glacial erosion before (and after) 25 million years ago. I am part of a project that hopes to core to the greenhouse world. Another project that is more likely to drill to Greenhouse world is "on hold" for lack of money because the first project is taking up too much of the NSF polar programs budget. I sited all the core locations for the latter project and did the regional seismic reflection stratigraphic correlations for that. It has "passed" on the science after about 5 years of resubmitting each year (I was not the lead person, but was involved in the proposals).

Chris

• Mauna Loa CO2