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This question suggests a theoretical possibility that hurricanes may be disrupted by removing heat from the system.

My question concerns the natural passage of a hurricane. Ocean water is warmer than it was in past decades due to climate change. This contributes to the strength of hurricanes. My question is: Is the surface ocean temperature measurably lowered by the passage of a hurricane? If so, what is the temperature differential?

I am not aware of any studies that have measured this. (But disrupting hurricane formation strikes me as analogous to preventing natural forest fires. Great idea, long term, possibly worse, consequences.) Any thoughts or calculations are welcome.

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closed as off-topic by Mołot, sphennings, MozerShmozer, Josh King, Vylix Sep 28 '17 at 3:30

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about worldbuilding, within the scope defined in the help center." – Mołot, sphennings, MozerShmozer, Josh King, Vylix
If this question can be reworded to fit the rules in the help center, please edit the question.

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Check out this image from the European Space Agency of Sea Surface Temperature Anomaly (normal SST - Measured SST) as three hurricanes (Kilo, Ignacio, and Jimena) move over the surface.Hurricanes Link to article: http://www.esa.int/spaceinimages/Images/2015/09/Hurricanes_change_temperature_of_sea_surface

There's actually two factors going on here- one, the hurricane does remove some thermal energy from the water directly, just as you remove water from hot soup by blowing on it; additionally, the hurricane forces ocean mixing and brings up cool water from deeper in the ocean.

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  • $\begingroup$ Up to 5 degrees Celsius cooler. Interesting! $\endgroup$ – Draco18s Sep 27 '17 at 18:25
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A slick idea, so to speak; +

Hurricanes do cool down the ocean by facilitating evaporation. Evaporation of a liquid carries heat away from that liquid. We facilitate evaporation of a hot cup of coffee by blowing on it and so offering more air into which the coffee might evaporate and so cool. Hurricanes facilitate evaporation 3 ways.

1: Warm air. Warm air can carry more moisture than cold air. That is why you can see your breath on a cold day - as your breath cools in the outside air, its water carrying capacity drops and you see the condensed water droplets. A hurricane brings warm air to the ocean surface where it collects evaporation.

  1. Low pressure air. Hurricanes have low pressure air. The lower the pressure in the overlying air the easier it is for water to evaporate off and stay there. A phase change from liquid to gas is easier when there are fewer gas molecules already up there crowding around. At altitude things evaporate faster and water boils cooler.

  2. Air exchange. Just like blowing on your coffee, the air exchange caused by the hurricane offers new air, not saturated with water, to come in and remove evaporate from the ocean surface. From https://spaceplace.nasa.gov/hurricanes/en/

    As the warm air continues to rise, the surrounding air swirls in to take its place. As the warmed, moist air rises and cools off, the water in the air forms clouds. The whole system of clouds and wind spins and grows, fed by the ocean's heat and water evaporating from the surface.

The net effect: the circumstances of the hurricane make a feedforward loop which allows the hurricane to take more heat energy from the ocean and build in strength. This is why hurricanes Peter out once they get over land.

But disrupting that loop - how to do it... You would need to prevent evaporation from the ocean surface over a large area.

You could achieve that with an enormous oil slick. Water cannot evaporate up through an overlying layer of oil.

from https://www.mnn.com/earth-matters/wilderness-resources/stories/the-13-largest-oil-spills-in-history

The worst oil spill in history wasn't an accident — it was deliberate. During the Gulf War, Iraqi forces attempted to prevent American soldiers from landing by opening valves at an offshore oil terminal and dumping oil from tankers. The oil resulted in a 4-inch thick oil slick that spread across 4,000 square miles in the Persian Gulf.

If you could shut down evaporation from a large enough surface of ocean by means of an oil slick, you could cut the growth engine of the hurricane. "Wah!" you may protest in the comments. "Wah! The tragedy of oil slicks!" Do a cost analysis before you wah so much. It is not outrageous especially as Mother Nature and her petro-hungry microbes do most of the oil slick cleanup gratis.

As scifi premises go I think this one is fairly awesome.

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    $\begingroup$ +1 for ocean bugs thinking oil is yummy, but I do think it's worth noting the out-of-balance, quickly vanishing food source has been attributed with making dead zones worse. $\endgroup$ – Sean Boddy Sep 12 '17 at 4:53
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The hurricane trives by using the energy taken from the ocean to the atmosphere by the evaporated water.

Thus it doesn't really cool down the ocean, since the water is already evaporated. It "simply" moves that energy from the ocean to somewhere else.

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  • $\begingroup$ Then the vapor pressure of where the hurricane was would be lowered, allowing more evaporation. It seems like there is still significant potential for surface cooling. $\endgroup$ – DPT Sep 9 '17 at 15:47
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    $\begingroup$ "It simply moves that energy from the ocean to somewhere else": Then by necessity it must cool the ocean. Just by "simply" moving the water vapor somewhere else, more water will evaporate thus cooling the remaining liquid. Hurricanes are one of the mechanisms by means of which the ocean sheds heat into the atmosphere. $\endgroup$ – AlexP Sep 9 '17 at 18:50

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