Hmmm?
Innumeracy is contagious, apparently.

tom

In the CAGW crowd really wants to be useful, solve the problems of alternative energy. I do not see such solutions, except for nuclear electricity. The current crop of renewables are a joke. With free, forced, backup, they are still completely uneconomical. And, there are no viable backup or storage methods. (The enviroloonies don't want nuclear either.)

A little less zealotry and more careful study would be a blessing.

There are multiple causes of climate change over Earth's history. Orbital variations are thought to be involved in geologically recent climate changes, along with various feedback mechanisms. In particular, when solar irradiance increases, this triggers the process of melting ice, which decreases the Earth's albedo, amplifying the warming. As the oceans are exposed, they release carbon into the atmosphere, again amplifying the warming trend. When solar irradiance decreases, this causes ice to form, increasing the Earth's albedo, amplifying the cooling. The oceans become locked under ice, trapping CO2, again amplifying the cooling trend. (Over longer trends, geological processes of ocean and rock scrub carbon from the atmosphere, while volcanoes emit carbon. So if the Earth were to freeze completely, the geological scrubbing would stop, and atmospheric carbon would increase until it triggered the melting process, restarting the scrubbing process.

These feedbacks help explain why Earth's climate tends to seesaw between warm and cool. It's a complex dynamical system with no single point of stability. Atmospheric carbon is both an effect and a cause.

These indicate that over the last several hundred thousand years (and several ice sheets advances and retreats) that temperature changes precede carbon dioxide changes by 400 to 800 years. This suggests that temperature changes drive carbon dioxide changes and that something else causes temperature changes, eg. Milankovic Cycles. Note that temperature is falling when carbon dioxide is at its peak.

Of course, these are large-scale fluctuations and might not reflect the mechanisms of the small-scale fluctuation we are now experiencing. Also, they do not imply that there is no greenhouse effect, merely that it is secondary over the time scale of the data.

One way of dealing with this, and I have heard people say it, is that the Vostock data is simply wrong, that the sampling and analysis were somehow screwed up.

Also, it sure does matter whether a photon is absorbed by CO2 vs. Water vs CH4 vs. SF6 vs. CHFCl2. All of these species are very different in their chemical properties such as Absorption Spectra, Heat Capacity or reactivity (lifetime in atmosphere or conversion to differently absorbing materials). And continuing in this theme, land masses have very different albedo (reflectivity) depending on whether you are talking about desert vs. forest vs. icecap. These terrain reflect light and retain heat very differently from the ocean.

It is unfortunate that once an issue becomes politically charged (especially when it comes to science) both sides often descend to fighting ignorance with ignorance. Reminds me of a great old SMBC comic "My anecdotal evidence is loud!" "Mine is louder!!"

Another crock of bullshit. You obviously didn't understand my answer. As far as mean planetary surface temperature is concerned, there is NO difference between a solar photon warming a CO2 molecule in the lower atmosphere, a water molecule in an ocean, or a speck of soil on land.

It's very simple to calculate that the Earth's average temperature without the greenhouse effect would be a chilly ≈-18°C rather than the balmy ≈+15°C that it is.

MingoV: @Zachriel: The models you mention are all crap because they don't include cloud formation.

They weren't models, but empirical measures using a variety of different methodologies.

ben: The question I have is, given Earth's temperature has not run away in the 2 billion years life has existed here, how can 3-4 times positive feedback be compatible with long term stability of climate?

Actually, the temperature of Earth has oscillated substantially over its history.

When my old stats prof said he had 'minor issues' with your work, it was time to switch to poli sci or sociology, or maybe just leave town.