If the troposphere is warming, how does this increase the lapse rate, unless the surface is warming more than the troposphere?

The lapse rate is the rate at which air temperature decreases with height. Increasing the lower troposphere temperature will decrease the lapse rate, the opposite of what you state.

For example, this illustrates the result of the scenario you describe:
http://www.rap.ucar.edu/weather/upper/grb.gif
[Green Bay, WI, USA sounding 12/7/2006 1200Z, LI 18.5]

Certainly no increasing convection in this profile.

Now a profile with better convection possibilities (it is winter, after all) is Tampa Bay, FL, USA:
http://www.rap.ucar.edu/weather/upper/tbw.gif
[12/7/2006 1200Z, LI 5.5]

Note the relatively steep lapse rate here.

When you say “Obviously the optimal temperature is warmer than existing”, it sure seems like you’re suggesting that we will all be better off with a warmer world, but maybe that’s just my dogma.

I think it’s clear that we are forcing the climate on one direction, and rather quickly from a geological perspective. If this was taking place over milllenia, I think we’d all be less concerned. As it is, as we discussed on another thread, it seems to be stressing a number of ecosytems and species.

We should be looking for the most cost-effective solutions (including doing a better job of protecting biodiversity and habitat), but taking into account that doing nothing is also costly.

I’ll leave to others the fight over CO2’s role in climate, but suffice it to say that I think your view is unjustifiedly sanguinary.

Your dogma is clouding your thinking. I am not suggesting that we *will* be better off with a warmer world. I am suggesting that, once the reality of feedbacks is discovered, we *might* be better off. We *might* be slightly worse off. We *might* be a lot worse off, although based on what we actually know about the effects of (strictly) CO2, the deck is stacked against that in that the only thing we really know is CO2 is the base of the food chain and it enhances convection.

My argument is that once one gets out of the lab we, realistically, have no clue about what CO2’s overall effects will be.

This is not to say that the 6+ billion of us, closely related to the lemming as we are, are not totally screwing up the environment.

However, the bottom line is that knowing what we know, or rather not knowing what we don’t know, some extra plant food may very well, in the big picture, be a good thing. The answer is another Manhattan project – not a hobbling of society.

It is unclear to me what point you are trying to make. You suggest that we will all be better off with a warmer world, but seem to argue that pumping GHGs like CO2 into the atmosphere hasn’t been pushing the atmosphere in the right direction – that the warming is strictly natural and anthropogenically caused or induced GHG emissions have no effect. Sounds to me that you are in effect denying that the so-called GHGs actually have warming effects.

What am I missing in summarizing your understanding of climate physics?

Your statement “We know CO2 is a GHG; the lag in the past tells us simply that other factors triggered warmings – warmings that were then further enhanced by rising CO2 levels” is incorrect. We do not, in fact, know that. Again, there is no evidence of any “enhancement” in the paleo record.

Coby – it may be tired to you, but it’s still true – your dogma notwishstanding.

This is such a tired and shallow argument about CO2 lagging behind temperature in the glacial cycles.
http://illconsidered.blogspot.com/2006/02/co2-lags-not-leads.html

You need a sensitivity to CO2 forcing of around 3oC/doubling to explain the magnitude of the temperature swings observed oer the last million years. But that is not the entirety of the geological record, there are examples of CO2/CH4 driven climate changes farther back, eg the PETM and the eruption of the Deccan Traps.

You must also dismiss very basic physics to pretend that CO2 doen’t cause warming.

I don’t get your point about population distro and warming being better. And what about sea level, we mostly live near the coasts?

As to the general notion that a warmer climate might be better in the end, please see this post:
http://illconsidered.blogspot.com/2006/02/whats-wrong-with-warm-weather.html

“There is no evidence that CO2 causes either warming or cooling in the paleo record. The temperature change preceeds the CO2 level change.”

Yes, but.

We know CO2 is a GHG; the lag in the past tells us simply that other factors triggered warmings – warmings that were then further enhanced by rising CO2 levels. Clearly higher CO2 levels do cause more warming, so we have clear cause for concern. Mankind’s GHG emissions have replaced Malinkovich cycles and other influences as the trigger.