# What would we need to stop a hurricane?

In Star Trek TNG, you hear about some sort of defense back on earth that is supposed to screen out all the bad weather. In the episode "True Q," it is mentioned several times as being capable of preventing/stopping a tornado.

Obviously such a system isn't possible today, but what would we need to stop a hurricane? What would we need to accomplish in order to stop/prevent a hurricane?

Clarity: This is science-based. I know we can't do this right now, so I'm looking for what we would need to cause. How we cause that is another matter entirely. (For example, maybe a drop in air pressure somewhere solves the whole thing. How we do that comes later.)

• If you remove the planet's atmosphere you can completely prevent hurricanes. I suggest sucking the atmosphere into storage and putting all the cities into pressurized bubbles too small to allow for significant weather phenomena. – Adam Davis Oct 6 '16 at 19:29
• A hurricane is nature's way of moving heat from the equator to the poles. If you stop hurricanes, that heat is going to build up, and is going to find an outlet somewhere. Do you really want to risk being in the path of that "somewhere", when we find out what it is? – Mark Oct 6 '16 at 20:07
• Have Barry Allen run around it really fast in the opposite direction. – Mason Wheeler Oct 6 '16 at 20:27
• I provided an answer and some comments below, but I thought it worth mentioning that stopping/preventing hurricanes might not necessarily be a good thing. Yes they do damage property and sometimes kill people, but they also perform vital natural functions. As Mark pointed out above, they redistribute the atmosphere's heat by carrying it away from equatorial regions. They also stir the waters in harbors and estuaries, which helps prevent stagnation. – Charles Burge Oct 6 '16 at 22:49
• A yuuuuuuge beautiful wall. – Whelkaholism Oct 7 '16 at 10:40

## Lots of wind turbines will mitigate the damage

What makes hurricanes so dangerous is the concentration of energy in a "small" area. Wind speeds are directly related to energy in the hurricane. If you can remove energy, the hurricane will naturally decrease in intensity. (I'm not sure if this qualifies as "stop the hurricane" but it will sure mitigate the damage from a hurricane.)

Mark Z. Jacobson at Stanford has done a lot of math to show that large numbers of turbines (tens of thousands) can suck enough energy out of a hurricane to decrease the damage done. Hurricane strength is inversely proportional to the number of turbines present subject to the law of diminishing returns. As the number of turbines goes up, the strength of the hurricane goes down.

## Total Prevention of Hurricanes?

If these turbine farms were setup in the band of the Atlantic and Pacific ocean where hurricanes/monsoons form, then this could suck enough energy out of the atmosphere to prevent or minimize hurricanes. The logistics of doing this will be immense but they might pay for themselves with the energy generated.

A comment on the original question stated, "A hurricane is nature's way of moving heat from the equator to the poles. If you stop hurricanes, that heat is going to build up, and is going to find an outlet somewhere." (Mark at Oct 6 '16 at 20:07) Let's talk about hurricanes at a smaller scale.

TL;DR

Hurricanes need the energy in warm, moist air to grow and sustain themselves. If you starve them of that energy, they don't form or don't grow as strong. Turbines extract mechanical energy from the lower atmosphere and convert it to electricity. Turbines can't remove all energy from the atmosphere (that'd be all kinds of bad), so we would still see localized low-to-high altitude energy exchanges in the form of thundstorms. Perhaps there will be more and stronger thunderstorms, but fewer hurricanes.

## Long Explanation

Most everyone has taken a bottle of water and tried to empty it over a sink. The familiar glub-glub-glub of water falling out, pause, then air coming in, pause, then water going out, is well known. Perhaps less known is that if you give the bottle a quick swirl, the bottle empties in a mere fraction of the glub-glub-glub approach. The swirling water opens a tube between the air in the bottle and outside air thus providing a "high speed", uninterrupted path for the air to get into the bottle. Hurricanes are the swirling water at the neck of the bottle. I shall demonstrate.

At the most abstract, we have a region of high energy and an area of low energy, in both the bottle example and the hurricane. For the bottle, the high potential area is the potential energy of the water held in the bottle, where the energy is provided by gravity. Hurricanes, on the other hand, have their energy provided by warm, moist air at low altitudes.

Over land, we see warm moist air trying to get to areas of low potential in the form of thunderstorms. The warm air rises towards the upper atmosphere forming giant cumulous clouds until the cooling effects of altitude and surrounding cold air halt any further upward progress. It's well known that stronger thunderstorms will produce taller clouds than weaker storms.

It is at this point that I will disagree with Mark. From the perspective of warm air on the surface of the ocean, the most accessible area of low potential is directly up, not pole-wards. Hurricanes are Nature's way of facilitating the movement of energy from low altitudes to high altitudes. Yes, generally pole-wards does have lower energy than the equator but on the scales we're discussing ie, "can turbines meaningfully attenuate hurricane strength?", the poles don't matter much since they are so very very far away. Also, hurricanes aren't the only way for energy to escape the equatorial waters; there are still tons of thunderstorms that do the same "job" as a hurricane just on a much smaller scale.

Let's go back to our bottle example: Over a very warm tropical ocean, we have an absolutely gigantic pool of energy in the form of warm humid air. This is exactly like the water held in the bottle, waiting to drain out. Thunderstorms form almost continuously at the equator in an area known as the Intertropical Convergence Zone.

Enough talk! What's with the turbines!? Hurricanes always peter out over land or cooler water because there isn't enough warm moist air to sustain the intense updrafts in the eye of the hurricane. Thus, the solution to hurricane formation is to starve the hurricane of warm wet air. Turbines can only convert mechanical energy within moving air to electricity, in other words, all they can do is slow down the wind...but that may be enough. Hurricanes are concentrations of energy and only form above some threshold of energy. If the turbines prevent the concentration of energy above that threshold then the hurricane won't form. Or, if a hurricane does form, it will be weaker in the presence of turbines. Instead of hurricanes, we could expect to see lots of tropical storms or thunderstorms over the Atlantic.

The Atlantic Oceanographic and Meteorological Laboratory has an interesting writeup on the energy released by a hurricane.

• From the Jacobson Source, 78,000 turbines for Hurricane Katrina would have reduced storm surge by 79%. – GER Oct 6 '16 at 19:37
• Why am I picturing thousands of whirling death blades spinning toward the shoreline at 120mph? – Comintern Oct 6 '16 at 22:50
• @Comintern...because you have a fatalist bent? Seriously though, the turbines would be rated to something like 140mph winds. Yes, there would be the occasional mechanical failure but not enough to prevent these turbines from working. – Green Oct 6 '16 at 22:53
• If these turbines need to be really far out at sea, instead of purely generating power they could have a mode that when a storm approaches they switch over and start pumping cold water from the depths and spraying it out as a mist into the approaching weather front. Could absorb a hell of a lot of additional energy from the storm, and its 100% achievable with today's Tech. – mccdyl001 Oct 7 '16 at 6:58
• I suggested that our local wind farm just reversed the turbines to counteract gales, but apparently they weren't big fans. – glenatron Oct 7 '16 at 13:04

What a hurricane boils down to is a large difference in air pressure between two parts of the earth. Air from the high-pressure region attempts to move toward the low pressure region. Along the way, coriolis forces influence its path and it ends up spiraling around the center of the low pressure. As the difference in pressure becomes larger, the velocity of the winds becomes higher.

Now, what if there were a way to let the air move from high to low without the coriolis effect standing in its way? A tunnel from the outside edge to the eye could do this. The air would still try to turn on its way through the tunnel, but the walls would get in the way and force the air to move along the path of the tunnel. This would allow the pressures to equalize without the resulting massive spiral of fast moving, destructive winds. The very things that gave birth to the hurricane likewise serve to kill it.

But wait, it's not as easy as it sounds. You are going to have trouble with scale and location. You need a really long tunnel, because hurricanes are many miles in diameter. Your tunnel needs to be very sturdy, as the winds rushing through it will be even stronger than in the hurricane itself. Finally, hurricanes tend to form over oceans, so your tunnel has to float. I'm not sure if any modern materials will meet these requirements. All this ignores how you are going to get your tunnel to the emerging hurricane in time to break it up.

Possible? Maybe, no-one has tested it yet. Practical? I have doubts.

• So the destructiveness is coming from the spin, and not all the warm air rising? Aka, take out the spin, you take out the wind? – Thomas Reinstate Monica Myron Oct 6 '16 at 18:29
• @ThomasMyron- the destructiveness comes from a mix of factors. This answer focuses on one of those factors, and a hypothetical way to circumvent it, thereby preventing all other factors from having a chance. – cobaltduck Oct 6 '16 at 18:56
• Well if stopping the spin would shut it down... what if we dropped an artificial hurricane on top of it spinning in the opposite direction? Disregarding for the moment if such a thing is possible, would the two winds just cancel each out? – Thomas Reinstate Monica Myron Oct 6 '16 at 18:58
• No. the tunnel is not "stopping the spin," it is allowing the pressure differential to equalize. It's similar to how a fire needs fuel, oxygen, and heat- take away one you can extinguish the fire. A hurricane needs warm water, a pressure differential, and the coriolis effect- take away one, you can kill the hurricane. – cobaltduck Oct 6 '16 at 19:19
• @ThomasMyron- Note also that hurricanes do not form over land (no water) near the poles (not warm enough) or near the equator (minimal coriolis forces). – cobaltduck Oct 6 '16 at 19:20

There are at least 2 things that are disruptive to hurricanes. One is high level wind shear, and the other is land masses with tall mountains. Presumably, you'd want to stop a hurricane as early in its development as possible, as that would require less energy and effort. In the Star Trek world, you might possibly be able to synthesize a very large but buoyant object, set it afloat in the hurricane's path, and let it disrupt the wind patterns. Granted, this would need to be an extremely large object, probably the size of a habitable island.

• What about the land mass with high mountains causes the hurricane to dissipate? Is it that the winds just run into the mountain and can't keep spinning? – Thomas Reinstate Monica Myron Oct 6 '16 at 18:31
• I don't know the exact physics, but I would assume it something similar to putting your hand in a small whirlpool (like in a bathtub drain). I live in Hawaii, and in recent years we've had a handful of hurricanes or tropical storms hit the Big Island, which has two 13,000-foot mountains on it. Whenever that happens, the storm gets broken up and no longer poses a significant threat to Maui and Oahu. (We still get heavy rain and lightning, but the winds are not typically strong enough to cause wide spread damage). – Charles Burge Oct 6 '16 at 18:41
• I think “habitable island” is not big enough. Hurricanes routinely hit Caribbean islands and then continue on to still do immense damage to the southeastern United States. Kilauea and Mauna Loa, now, those are big enough, but they’re huge. – KRyan Oct 6 '16 at 20:28
• I think the issue is height rather than footprint. I was thinking something like a big Styrofoam pyramid with a height of at least 10,000 feet, and a base of perhaps 2 to 5 miles. Yes, I realize that's a lot of material, but it should only need to be deployed for a day or two, and when you're done with it you can convert it back to energy. – Charles Burge Oct 6 '16 at 20:33
• On second thought, it wouldn't even need to be a solid object. You could just create a force field, maybe with a wire frame. – Charles Burge Oct 6 '16 at 22:23

In addition to the three solid answers already, there's one more I can propose: a massive release of cold air or cold water. Hurricanes are heat powered. Atlantic hurricanes weaken as they travel north over colder water. It seems if you could bring the temperature down then the storm ends.

The problem is scale. There isn't enough ice in the North Atlantic to make a dent in Hurricane Matthew. Here's one NPR article discussing it: http://www.npr.org/templates/story/story.php?storyId=5475155 So if you want to use this, you aren't looking at something humans do... you're looking at something nature might do on a grand scale, like an undersea salt dome collapsing and releasing a massive Gulf-wide release of methane which drags deep ocean cold water to the surface. Pretty much a once-in-a-lifetime scenario.

• Laser cooling should work. If we only can set a chain reaction of atoms cooling down and using released energy to cool down others.. – kagali-san Oct 7 '16 at 7:35
• Matthew has more energy than SEVERAL atomic bombs. I have doubts about the energy required for laser cooling. I'd need numbers to believe it. – SRM Oct 7 '16 at 17:03

All of these answers seem logical enough but don't address what fundamentally 'powers' a hurricane which is latent heat energy, that is to say the energy released when water vapor condenses in the upper atmosphere. It would seem then that interupting this condensation would address this problem, perhaps use some sort of dehumidifing device that can be launched into the atmosphere?

Create disruption along the upper layers of the hurricane spiral

One sufficiently large swath of wind current disruptor traveling in any one straight direction across the entire upper level of the spiral will break it up into many smaller spirals. Smaller spirals still handles the atmospheric temperature exchange and distributes the effects in many smaller local areas all along the edges and within the system. These smaller spirals can still be quite destructive, so doing this before landfall as others recommend is advisable.

If it helps to visualize this, in a bucket of clear water containing algae litter, get it swirling until you see all the algae swirling centralized in the middle of the bottom of the bucket. Take a net the width of the swirl and push a swath through the top layer of your mini hurricane. Observe the algae form into many small little "tornados" instead of the one large swirl. They will not reform into the larger swirl unless you re-energize the entire system again.

• How much of a decrease in destructive power are we talking about? Also, would the swirls still all move in the same direction, or go in different directions? – Thomas Reinstate Monica Myron Sep 10 '17 at 0:41
• @Thomas Myron It would depend on the specific storm system and type of disruptor used. In my example, the disruptor has many smaller compartments within the whole (the net) that allows some air to pass through and disrupts other airflow areas, introducing a different chaotic influence than would a solid blade. It can result in varying directions of the many smaller whirlwinds. – N2ition Sep 10 '17 at 3:58
• openshadeball.org – joshua.thomas.bird Oct 18 '19 at 20:38

I laid out a scheme to stop hurricanes with oil slicks in this related idea. Do hurricanes reduce the thermal energy of the water they pass over, and if so by how much?

Here is an synopsis:

Hurricanes 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.

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. 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.

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.

I posted the scheme on the half bakery. http://www.halfbakery.com/idea/Hamstring_20hurricanes_20via_20oil_20slicks#1504958339

where Max observed

I don't know if it would work or not, but there are probably better > things to use than oil.
What you want is a chemical that is cheap, floats on water >and doesn't dissolve, and is either biodegradeable (more so than regular oil), UV-degradeable, or evaporates slowly (over days) as a non-harmful vapour.

How much would you need? Well, the minimum needed is a single >molecular layer. Single-molecule layers will form readily - it's a >classic school experiment to estimate the size of an oil molecule. So, suppose the layer is 10nm thick (that's a fairly long molecule). And the area is, let's say, 10^6 square km, or 10^12 square metres.

That gives you a total volume of 10^4 cubic metres, or say 10,000 >tonnes of your compound. This is a tiny fraction of what a big tanker can carry. Even if the cost were £100 per tonne, you're still looking at only £1M, which seems less than the cost of reroofing every building.

Certainly a 4 inch slick is wasteful when you need only a thin layer to retard evaporation. I am not sure there will be anything much cheaper than oil, but using lighter, more volatile fractions of crude oil without the tarry asphalt would make the project shorter in duration and less yucky. Or use vegetable oil. Other benefits: you can deploy this fast and it spreads itself out by itself.

Or you could block evaporation with something more reusable, and more beautiful, and roll it out when any hurricanes threaten. I see that Christo is still alive. I am sure he would be delighted to advise on a (much) scaled up project similar to his past endeavors - for example

Lowering the temperature of the ocean surface is sufficient to prevent hurricanes, given understanding of where they will form. The warm layer of ocean water is relatively thin, a hundred feet or so below the surface there is much cooler water.

Enough machines to mix the layers might work. Explanation of how they work is in chapters 4, 5 of Superfreakonomics.

• It would probably be sufficient to stop evaporation of water from the ocean surface under the hurricane. A gargantuan oil spill would work in theory. In practice that's like cracking a safe with a megatonne nuke. – nigel222 Oct 11 '16 at 20:14
• openshadeball.org – joshua.thomas.bird Oct 18 '19 at 20:36

They key is to disrupt the winds during the storm's infancy - before it has time to gain power. Maybe dropping a few daisy cutters in a pattern around the small funnel as soon as it forms would disrupt and scatter it.

• openshadeball.org – joshua.thomas.bird Oct 18 '19 at 20:36

Prevention at the Source

Atlantic Hurricanes, for example, form from the winds coming over the Sahara, and blowing right over the hot Atlantic. Under a monumentally inefficient and unnecessary effort for foresting the Sahara at least on the Western edge, will mitigate against the effects of the wind approaching the Atlantic.

Find the source for other storms and tackle it - not sure if this would work over the Pacific though.

https://worldbuilding.stackexchange.com/a/90753/42731

1. If enough hovering turbines with multidirectional remote control system were built, then they can to help cool down land and water atmosphere closest to the equator.

2. Enough of these turbines could be used to minimize warm moist air build up from where it starts. They also can power up their recycable energy cells to keep them hovering and plus possibly more consumable energy cells for other uses.