Ok here’s one problems I have with AGW.?

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A for effort!

You're reading the science, and doing the math correctly. In particular, your computation of CO2 radiative forcing is correct. (I could quibble a bit and point out that CO2 is currently 386, and also that equation 3 is actually a bit more accurate than equation 1 ... but the differences are small.)

The problem you have is that the extra 1.6 W/m² isn't going directly into the air. I't's going mostly into the sea. And that creates a lot of complications, because then you have to figure how deep a surface layer of ocean is directly affected, and how much of that heat goes from the surface layer into the air, and how much goes into the deeper ocean.

Further, the fraction that does end up in the air doesn't go all the way up to the top of the atmosphere. The whole atmosphere isn't warming, just the surface and the troposphere, while the stratosphere is cooling (because more greenhouse gases means less IR is getting up that high).

And yet another complication is the effects of various feedbacks in the climate system, which amplify the direct forcing. These feedbacks are both positive and negative, although when taken together the net is positive.

All that is pretty complex, which is why climate scientists use complex models of the climate system. If you want a simpler way to do things, you can just apply a factor known as "climate sensitivity" to your radiative forcing result. But because of all these issues, however, the value of climate sensitivity isn't well known either. The IPCC TAR gave it as .5 K/W/m² ± 50%. Which means we should expect 1.6 x 0.5 = 0.8° C increase, about what we have actually seen....Show more

I'm sure someone else will be able to give a better answer, but the first obvious problem I see is that you multiplied it by the number of seconds in a year. Why?

The radiative forcing is a measurement of the flux imbalance. You can do a quick and dirty estimate of the expected temperature difference with the Stefan Boltzmann law of blackbody radiation.
http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law#Planetary_Equilibrium_Temperature

j* = (5.67 E -8)(T^4)

Starting with an average Earth temperature of 288 K, we get a radiative flux of 390.079 w/m^2--a bit higher than the actual average flux of 342, but it'll do.

390.079 + 1.63 = 391.709 W/m^2. Working backwards:

391.709 = (5.67 E -8)(T^4), solve for T to get 288.3 K.

So by the extremely simplified calculation you can expect a +0.3 C rise from the 1.63 w/m^2 forcing. Of course this is complicated by feedbacks, the earth's albedo, the lag time for RF to equate with temp, band saturation of CO2, etc.

But at least with this most simple of calculation you can see that the estimates are not horribly wrong....Show more

First I would like to say I am no expert on this subject or could even do the math your link contains. Your calculation of 5c may be correct. I recently seen an article about how the pollution in the air is actually counter-acting the effects of global warming, thus slowing the rate of temperature rise by blocking sunlight. Other things contribute to this effect such as when Mt. St. Helen's erupted and spewed ash into the atmosphere. Just not on the grand scale of when the dinosaurs became extinct. Like I said,I couldn't do the math, but wondered if the equation takes this into consideration. Just thought this might be why 5c is high....Show more

EDIT

I was thinking that these calculations were Richard's original thought. Looks like it's a junkscience.com Steven Milloy thing. At the very least Richard should credit the tobacco lobbyist for the material.

http://www.junkscience.com/Greenhouse/forcing.html

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Your implied estimate of climate sensitivity is absolutely enormous! Thank goodness the situation isn't that dire.

Your radiative forcing to global mean temperature change analysis is quite simplistic. See the Stefan-Boltzmann law for starters.

http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law#Temperature_of_the_Earth

From here we can calculate about 1 C of forcing from a doubling of CO2. Then, of course, there's feedbacks, which get us in the 2-4.5 C range. Of course, you then have to consider equilbrium - the time lag between the forcing and the temperature change. Lastly, we have to consider other forcings, such as the cooling effect of anthropogenic sulfates.

http://www.realclimate.org/index.php/archives/2006/11/cuckoo-science/...Show more

Your calculations are kind of right, but you need to factor in the thermal mass of the ocean and time lag for the heat to mix into it. The forcing isn't uniform with latitude, so neither will the heating.

The disconnect you're observing is because the planet hasn't yet equilibrated to the rise in the forcing. Once that happens, the expected rise in temperature of the tropics, for instance, will be about 5 K, just as you calculated. The equilibration will take a while, on order of a few hundred years.

http://www.ncdc.noaa.gov/paleo/globalwarming/temperature-change.html

There is nothing fundamentally wrong with the science. However, a lot of people want there to be because they can't accept it's correct....Show more