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Wow, wonder where they are doing that? At STP, water freezes at 32 degrees F.

Let's see. Since -100 F is basically 200 Kelvin, we can consult our phase diagram for water and see what the pressure would have to be in order for water to be a liquid at that temperature!

...

Oh. Looks like you were just wrong. Either that or "water" means "antifreeze".

Most materials do the same. There are very few liquids that don't subliminate in a vacum.

BZZZZT!! The water absorption frequency is up around 21 GHz and the liquid absorption line is REALLY broad. I have seen a large industrial "microwave oven" running at 916 MHz - so there is nothing magical about 2.4 GHz.

I stand corrected.

However, there is something magical in 2.4 GHz frequency. According to http://www.lsbu.ac.uk/water/microwave.html, 2.4 GHz frequency is optimal for warming food in microwave ovens.

Well, crystalizing room temperature water is a little hard to swallow, (water's too simple a chemical to do much to it)

water phase diagram. It shows more of the different types of ices, and the axes have scales. It is quite evident that pure water is a solid at Titan's surface (95 K, ~1.5 8 10^5 Pa) . In fact it's probably Ice Ic instead of the familiar Ice Ih.

A kind of ice-9 but for real.

Since water vapour is a strong absorber in all wavelengths one would expect the lower atmosphere to warm slightly and the upper atmosphere to cool. There is data to support this.

Water is not a strong absorber at all wavelengths. Take a look

Water is, for all intents, *transparent* in the visible wavelengths both as a gas and as a liquid. It's a good thing too, because the "visible" light (the light that goes through all that water vapor in the atmosphere and reaches the surface) happens to be the light that we humans evolved to see with. It also "just so happens" that the sun (as a near-black body emitter at about 5000 K) emits most of its energy at the visible wavelengths (coincidence?). . .

So, water vapor is not absorbing most of the energy that comes from the sun (even if it is a strong absorber at most infrared and UV wavelengths); it is, in fact, transparent to most of that energy until it condenses into clouds, which makes it reflect a lot of the visible wavelengths.

If you check the IPCC report in chapter 7 you will find that they simply decided to ignore the role of water vapour in their models. Given that the concentration of water vapour is at least 2 orders of magnitude more significant than CO2, this IMHO is a silly thing to do. You simply cannot ignore the most significant variable and expect your model to be meaningful.

First of all, they don't actually ignore water. The tend not to trust atmospheric models that have globally averaged water vapor. The surface water (oceans, lakes, rivers, etc.) are important energy transport mechanisms that are much better understood than the greenhouse gas, water vapor. Read chapter 8 of the IPCC. . .

You also simply cannot ignore the fact that concentration is not the only variable when it comes to global warming. How efficeint is water vapor at absorbing in the visible and UV and re-emitting in the infrared? how does its non-even spatial distribution affect its efficeincy as a greenhouse gas? Compare that with CO2 and, say SF6, whose lifetimes in the atmosphere are much, much greater than water.

Go back and read the IPCC again. . . The atmospheric lifetime of CO2 is on the order of 50-200 years. The atmospheric lifetime of H2O is much shorter than that of CO2 (nobody is really sure by how much shorter). However, the biggest thing about water vapor is that as the concentration in the atmosphere increases, it does trap more energy from the sun, but it also increases the likelyhood that the vapor will condense to form clouds, thus increasing the "albedo" of the atmosphere, lowering the amount of energy that stays on the earth. It's difficult to model and thus is usually ignored when other gases like CO2 (which only *increase* the amount of heat retained) are increasing in concentration.

Another problem with water vapor is that it isn't evenly distributed throughout the atmosphere, either "horizontally", vertically, or temporally, mostly because its atmospheric lifetime is so short. CO2 and other strong, long lived gases are much more evenly distributed, so it's relatively simple to create a mathematical model of the effects CO2 et al. have on the energy budget of the Earth. It's not so simple with a patchy gas like water vapor.

The jury is NOT out on the matter of the increase of the average temperature of the earth. It IS increasing. The jury is ou

At some temps, adding pressure will melt ice, then more pressure will freeze it again into a different type of ice.

The mantle is at really absurd pressures, on the order of millions of atmospheres. Water at this pressure does not become vapor, but rather Something Weird.