Question for AGW experts

[icefisher]

If greenhouse gases provide for a net warming of the atmosphere, why is it that tropical climates tend to be cooler than desert climates during the day and desert climates tend to cooler than tropical climates at night?

I get the part about deserts cooling faster, thats the "traditional" greenhouse theory. But if a tropic night cools less and starts higher why doesn't the tropical climate temperature just blow away the desert climate the next morning when the sun starts reheating the surface?

Simple enough of a question huh? Should be a piece of cake for you AGW experts.

[socold]

probably clouds

[ron]

It is unbelievably cloudy in the arctic circle. Maybe that's why it's so cold.

Except it's cloudiest when it's the warmest. Huh! Go figure.

[jimg]

Humidity.
Something tropics have in plenty, but deserts lack.
Particularly during the summer months, desert air is really dry.

In the summer months, a tropical locale may have 100% humidity, but the desert might only have 10% or less.

[matt]

In the daytime, tropical areas are kept cooler by evaporation. In the nighttime, desert climates are cooled by lack of a water vapour "blanket."

[FurryCatHerder]

Apr 4, 2009 15:57:18 GMT matt said:

In the daytime, tropical areas are kept cooler by evaporation. In the nighttime, desert climates are cooled by lack of a water vapour "blanket."

There's also the fact that days are more uniform in length in the tropics. The Desert Southwest of the US has longer summer days than in a place like Aruba or Hawaii. The lack of moisture in the desert air means all that heat makes it to the ground, which lacks vegetation for transpirational cooling (stand under a tree and you'll understand).

Spend time in both climate regions. All will become very clear, very fast. Especially at night.

[poitsplace]

Apr 4, 2009 15:57:18 GMT matt said:

In the daytime, tropical areas are kept cooler by evaporation. In the nighttime, desert climates are cooled by lack of a water vapour "blanket."

Well they're not so much cooled by a lack of water vapor as they are...not kept warm by the latent heat released once they hit dew point.

[steve]

Apr 8, 2009 17:20:22 GMT icefisher said:

This humidity thing is extremely powerful in its own right. This stuff has huge effects on the atmosphere. With the power to shift warming rates 40 degrees in the course of an afternoon.

I believe in the greenhouse effect but how it works seems to be very poorly explained. Adiabatic pressures would seem to be a very poorly explained element as part of the GH theory.

I'm not sure how to take this post. Have you read up on Myrhe, Trenberth, MODTRAN and HITRAN documentation, documentation of some of the major models etc, papers on observations of earth radiation balance and changes to it, even papers from sceptics such as Lindzen and Douglass? Do you know more than Roy Spencer who recently posted an article "in defence of the greenhouse effect"?

The rest of your post indicates a degree of hand-waving uncertainty based on possibly incorrect descriptions of the effect. Now none of us here are world experts on this, but perhaps you should look harder for better explanations before you conclude that the poor explanations you have so far found leave a possibility that all these stupid scientists have missed the obvious.

[icefisher]

Apr 8, 2009 17:47:00 GMT steve said:

Apr 8, 2009 17:20:22 GMT icefisher said:

This humidity thing is extremely powerful in its own right. This stuff has huge effects on the atmosphere. With the power to shift warming rates 40 degrees in the course of an afternoon.

I believe in the greenhouse effect but how it works seems to be very poorly explained. Adiabatic pressures would seem to be a very poorly explained element as part of the GH theory.

I'm not sure how to take this post. Have you read up on Myrhe, Trenberth, MODTRAN and HITRAN documentation, documentation of some of the major models etc, papers on observations of earth radiation balance and changes to it, even papers from sceptics such as Lindzen and Douglass? Do you know more than Roy Spencer who recently posted an article "in defence of the greenhouse effect"?

The rest of your post indicates a degree of hand-waving uncertainty based on possibly incorrect descriptions of the effect. Now none of us here are world experts on this, but perhaps you should look harder for better explanations before you conclude that the poor explanations you have so far found leave a possibility that all these stupid scientists have missed the obvious.

Your entire post is a fallacy known as an appeal to popularity whereas I have a bit more of a handle on the effects of mass hysteria.

I think you are being dishonest in your assessment that I am judging everybody wrong. Not everybody shares the same point of view. The list of dissenting scientists is growing.

All I am asking for is some simple explanations like how did you discount natural warming and a nice model to explain the actual physical process (not as simple as the "budget" diagrams) but actual physical processes. I would think starting from a spectra analysis of earthshine would be a great place to start then move down into the atmosphere carefully discussing the various affects such as adiabatic pressures, absorption, conduction, storage etc.

Off the top of my head it seems to me there is a lot of criticism of the "popular" model from nearly every angle. That does not provide much comfort.

But one is guaranteed the minute one starts talking details the argument immediately shifts to a list of names and concensus rather than processes. . . .for a seasoned auditor that loves to hunt thats like a bull elk trumpeting in woods.