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If there was no water on the earth would there still be wind? If the planet was basically a desert from pole to pole, east to west, would the wind still blow? I understand that wind is a result of a difference in pressure, but is it true that water being naturally cooler is what creates that pressure difference?

I don't find any answers that clearly state whether or not wind would still exist without water and whether or not water is the originating source of wind. I see that most of the answers that talk about the source of wind say that cooler air moves in as warmer air rises, but wouldn't all the air in the world be warm/hot without water to cool it? The pressure difference seems to be cool versus warm.

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  • $\begingroup$ Your question is different, but I wanted to connect it with these related questions: How would the earth look without water in the oceans? and How would plate tectonics differ if earth had no water?. $\endgroup$ – kwinkunks Nov 12 '15 at 17:18
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    $\begingroup$ Is there wind on Mars? quora.com/Is-there-wind-on-Mars $\endgroup$ – Isopycnal Oscillation Nov 12 '15 at 19:21
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    $\begingroup$ In fact, Earth without oceans would have even stronger winds than what we observe. Water has such high heat capacity that it effectively dampens horizontal temperature gradients due to insolation. $\endgroup$ – milancurcic Nov 12 '15 at 19:45
  • $\begingroup$ @milancurcic that may be correct, but water condensation plays a role in high and low pressure systems and in bringing heat to the upper atmosphere. We'd have no hurricanes if we had no water. I think it's more complicated than that. $\endgroup$ – userLTK Nov 13 '15 at 9:45
  • $\begingroup$ @userLTK Yes... $\endgroup$ – milancurcic Nov 13 '15 at 17:55
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I wouldn't say water is naturally cooler than air. What I would say is that water has a higher heat capacity than air. This means it takes more energy to affect the same increase in temperature and conversely it takes water longer to cool down than air. You can see this at night near bodies of water when the sea breeze changes to a land breeze as the land becomes cooler than the water - water temperatures tend to be stable across diurnal cycles.

I would also contest the statement that water cools the air. Water does both heating and cooling. When water evaporates into air, the air cools. However take a look at any thunderstorm you see -- that is water causing heating as it condenses and freezes. Water on the surface can also contribute to both heating and cooling. During the day the cool water surface will have a heat flux that cools the air while at night the opposite may be true. This depends on the air temperature and the SST.

Now on to your question, yes, there would still be wind if there were no water. The energy that drives the wind is differential solar heating at the earths surface. Variations in the surface topography and the shape of the earth mean that the solar flux isn't constant across the earth. As long as we have a sun we will have surface pressure differences and wind. Without water we would also see a stronger equator-to-pole temperature gradient (look at temperature variations right now on continents versus open ocean). This would result in stronger winds that we see today.

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  • $\begingroup$ I have a follow up question to the wind/water thing. Since there would definitely be wind with no water and it would actually be stronger wind, am I right in assuming that dust/sand storms would happen? If so, what would be the size and duration? Would it be out of the realm of possibility that a storm could grow so large that it could just keep going? Never stopping? $\endgroup$ – Donovan Nov 13 '15 at 16:08
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    $\begingroup$ @donovan you might consider marking this as the accepted answer, and unaccepting the currently accepted one $\endgroup$ – enigma Nov 14 '15 at 3:50
  • $\begingroup$ Ironically, answers to the opposite question asked recently have some people hinting that winds would increase with water only. Certainly can see arguments for both sides on both questions. But perhaps we should just settle with no input on whether they'd be weaker or stronger, instead a: "it's complicated, and would be based upon the specific dynamical evolution that would result" :-) $\endgroup$ – JeopardyTempest Jul 24 '17 at 1:12
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A necessary (but not sufficient) condition for hurricanes to form on Earth if there was no water (dry hurricanes) is that the lapse rate would have to exceed the dry adiabatic by a large enough margin over a sufficiently large region of the troposphere. By contrast, with water vapor, this necessary (but not sufficient) condition is mitigated to a lapse rate merely exceeding the moist adiabatic by a large enough margin over a sufficiently large region of the troposphere. Dry hurricanes have been simulated on computers. While the laws of physics don't forbid dry hurricanes in principle, in practice it would be at least very difficult and maybe impossible to attain the the required steep lapse rate over a sufficiently large region of the troposphere, even with no solar energy expended in evaporation on a dry Earth.

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    $\begingroup$ The question is about winds. Not just hurricanes. $\endgroup$ – farrenthorpe Jul 23 '17 at 16:47
  • $\begingroup$ The answer by casey addressed winds in general, so I thought that I would answer concerning hurricanes in particular. $\endgroup$ – Jack Denur Aug 1 '17 at 20:46
  • $\begingroup$ OK, it may help if you address the main question first though, and then get into more detail. I didn't down vote this. $\endgroup$ – farrenthorpe Aug 1 '17 at 22:54
  • $\begingroup$ Casey addressed the main question so well that there is not much that I can add. One point: Average wind speeds could be higher on a waterless Earth because temperature gradients would be greater. But without severe thunderstorms, hurricanes, and tornadoes, extreme wind speeds probably wouldn't be as high. $\endgroup$ – Jack Denur Aug 2 '17 at 2:52
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If the world was uniform but still spinning, the difference between night and day would be enough to create a wind. Add mountains etc, plenty of temperature differences to create wind.

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    $\begingroup$ while this is true... I feel it avoids the reason why (e.g. dynamic solar heating). $\endgroup$ – farrenthorpe Nov 12 '15 at 20:09

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