Can we cool the oceans?

[Donk]

The oceans are warming up. This leads to many problems, such as:

• Tropical storms gain energy from warm water. Warmer water = more storms, or more dangerous storms.
• Warm ocean water is less fertile. Less fertile water = less carbon sequestration.
• Too-warm water is killing coral.

So, can we do anything about it? Possibly. In a small way. But maybe it'll help with the coral at least.

A river going over a weir oxygenates the water and cools it by evaporation. For the seas, waves do the same. Gentle lapping wavelets don't do much, but crashing breakers do, with the foam creating a much larger air/water boundary. We need something sitting in the water that will cause waves to break on it. Something like this?



I'm calling it the Spumifier for now. Pretty, isn't it? I'd expect it to be around 10m across. If the skirt is deeper than the incoming wave, the wave will break rather than make the Spumifier bob up and down. The upper part has a sawtooth edge to make more foam.

Tropical ocean normally evaporates around 120cm of water per year. There's really no good way to say how much the Spumifier will increase this, but I would guess at a factor of 3 at least.

If used for a particular part of the ocean it would be anchored. There could be advantages in putting it in the open ocean – cooling and oxygenating a dead area could bring it to life, helping both fisheries and carbon sequestration.

Yes, I know that water vapour is a greenhouse gas. But when you have square kilometres of ocean all putting their 120cm per year into the atmosphere, a few spots of increased evaporation aren't going to make that much difference.

Or even a few thousand spots. Put a lot of them upwind of a drought area, it might help a little?

[InfiniteNow]

My initial instinct tells me that you will face an issue with scale. You are dealing with enormous volumes of water in the oceans, but the evaporation of which you speak is a rather tiny volume by comparison.

I really don't know enough about this topic to consider my thought above relevant, but it was a thought all the same. Sounds a bit to me like you're trying to cool an entire football stadium in Texas using the air generated from the wings of a butterfly.


Have you read about a similar idea put forth recently by Bill Gates?
Bill Gates, Infected By Geoengineering Virus, Patents Hurricane Mitigation Devices For Gulf Of Mexico : TreeHugger

[Boerseun]

Well, in principle it could work by increasing the contact area available for evaporation. But like INow said, scale will destroy this idea from the get-go. You'd need literally millions of these things to make any kind of an impact anywhere.

Which, if it does work to the required scale, will significantly increase water vapor in the atmosphere - which is an even more efficient greenhouse gas than CO2, which, in turn, will heat up the oceans even further, which means you'll need more of them, which will then supply even more water vapor, which will then heat up the oceans even more, etc.

[Donk]

The title was a broad-brush attractor - newspapers use the same trick for their headlines My apologies.

The idea isn't to make a difference to the overall temperature. Just to bring some cool, oxygenated water to where it can do some good.

[Donk]

Originally Posted by InfiniteNow

Have you read about a similar idea put forth recently by Bill Gates?
Bill Gates, Infected By Geoengineering Virus, Patents Hurricane Mitigation Devices For Gulf Of Mexico : TreeHugger

Thanks for the link, IN. I can see the similarity. But cooling surface waters by brute-force mixing with lower, cooler, anoxic water is definitely not the way to go. I'd like to see some effort going into reviving dead areas, not expanding them.

[Turtle]

Originally Posted by Donk

The oceans are warming up. ...
So, can we do anything about it? Possibly. In a small way. But maybe it'll help with the coral at least.

...

of the 3 main factors affecting evaporation rates of open waters, sunlight is the primary actor.

BBC - Science & Nature - Horizon

DR MICHAEL RODERICK: Well it turns out in fact that the key things for pan evaporation are the sunlight, the humidity and the wind. But really the sunlight is a really dominant term there.

NARRATOR: They found that it was the energy of the photons hitting the surface, the actual sunlight, that kicks the water molecules out of the pan and into the atmosphere. And so they too reached an extraordinary conclusion. ...

making your stepped spuminator reflective ought to add to the evaporation achieved.

[freeztar]

I get the same impression as others. It seems like a great idea, but ultimately futile.

The Bill Gates et al idea scares me. The ocean has temperature gradients and they work to keep everything balanced. I'm not an ocean scientist, but from my studies of freshwater systems, it is very clear that mixing of temperature gradients can have dramatic effects. For instance, see here, here, and here. Organisms are adapted to certain temperatures and levels of dissolved oxygen. I'm curious as to how much thought they've put into this. It wouldn't be the first time I've seen engineers completely ignore the environmental repercussions of their designs.

In the recent issue of Nat Geo, they have an interesting article about cooling the Earth (including ocean and land) by employing billions of reflective "umbrellas" between us and the sun. Again, it's a bit frightening, but at the same time a lot more controllable. As Turtle pointed out, the main driver is solar so hitting the problem at the source may be the best bet.

Shading the Earth — National Geographic Magazine