APOD: Ship Tracks over the Pacific Ocean (2022 Jun 08)

[APOD Robot]

Ship Tracks over the Pacific Ocean

Explanation: What are those unusual streaks? Some images of planet Earth show clear bright streaks that follow the paths of ships. Known as ship tracks, these low and narrow bands are caused by the ship's engine exhaust. Water vapor condenses around small bits of exhaust known as aerosols, which soon grow into floating water drops that efficiently reflect sunlight. Ship tracks were first discovered in 1965 in Earth images taken by NASA's TIROS satellites. Multiple ship tracks are visible across the featured image that was captured in 2009 over the Pacific Ocean by the MODIS instrument on NASA's Terra satellite. Inspired by ship-tracks, some scientists have suggested deploying a network of floating buoys in the worlds' oceans that spray salt-aerosol containing sea-water into the air so that, with the help of the wind, streams of sunlight-reflecting clouds would also form. Why do this? These human-made clouds could reflect so much sunlight they might help fight global warming.

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[Ann]

Ship Tracks over the Pacific Ocean, Earth. Image Credit: NASA, Terra, MODIS

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Grooves and possible plumes of water vapor on Europa, moon of Jupiter. Credits: NASA/ESA/W. Sparks (STScI)/USGS Astrogeology Science Center

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One wonders what ships have been plying the seas of Europa?

Ann

[Ironwood]

What a great idea! I just remote started my SUV to assist in combatting global warming. I'll let it warm up then go drive around making cooling clouds.

[Starlightasru]

Perhaps modify the ship's systems to create the clouds.

[rstevenson]

Would the reflectivity of the clouds fully offset the CO2 released by the ships' diesel engines? Is this just another example of perpetual motion-like wishful thinking?

Rob

[Chris Peterson]

Perhaps modify the ship's systems to create the clouds.

The clouds produced by a ship don't significantly offset the CO₂ produced by the ship. The proposed geoengineering solutions produce the clouds but don't add to atmospheric CO₂. Also, the aerosols produced by the ships that seed the clouds are harmful in their own right, unlike the geoengineering approach that simply uses salt.

[Chris Peterson]

Would the reflectivity of the clouds fully offset the CO2 released by the ships' diesel engines? Is this just another example of perpetual motion-like wishful thinking?

The geoengineering proposal, of course, doesn't use technology that releases CO₂ or dangerous aerosols.

[heehaw]

ESPOD is very good today.

[orin stepanek]

ShipTracks_Terra_960.jpg

Maybe someday; man will be able to control the weather!? Maybe;
remember I said maybe; or maybe the weather will wipe us out first!
I wish it were 1950 again, when I was a boy and not wonder what the
future will bring! Que sierra sierra !

[guest again]

One wonders what ships have been plying the seas of Europa?

Ann

Ice breakers?

[Sa Ji Tario]

When the tragedy of the US Twin Towers suspended flights for three days, a temperature difference of three degrees was found caused by the lack of aerosols left by high-altitude aircraft that returned much of the solar infrared rays to space.

[Chris Peterson]

When the tragedy of the US Twin Towers suspended flights for three days, a temperature difference of three degrees was found caused by the lack of aerosols left by high-altitude aircraft that returned much of the solar infrared rays to space.

Not globally, though. This was a regional effect.

[Sa Ji Tario]

Right Chris, I forgot to mention it.

[florid_snow]

A key phrase here is "aerosol susceptibility" because broadly speaking, there is a large contrast from land to ocean for the amount of particulate matter floating in the air - aka the aerosol concentration is much higher over land than over the ocean. So running your SUV does not cause this effect over land, it is only over the ocean where the atmosphere is typically susceptible to aerosol injection for cloud brightening. And this only really works a few days per month in different small sections of the ocean where there is the particular thermodynamic situation where a cloud might condense but does not due to a relative lack of particles.

This continues to be an active area of research, I wish this APOD had linked to a few more relevant articles, like this recent article in Science which basically claims the total susceptibility of the atmosphere is too small for this to really be a viable method to counter-act CO2 climate change.

https://www.science.org/doi/10.1126/science.abd3980

[Astronymus]

So this is how the microplastic ends up on Mount Everest and Antarctica.

[Chris Peterson]

A key phrase here is "aerosol susceptibility" because broadly speaking, there is a large contrast from land to ocean for the amount of particulate matter floating in the air - aka the aerosol concentration is much higher over land than over the ocean. So running your SUV does not cause this effect over land, it is only over the ocean where the atmosphere is typically susceptible to aerosol injection for cloud brightening. And this only really works a few days per month in different small sections of the ocean where there is the particular thermodynamic situation where a cloud might condense but does not due to a relative lack of particles.

This continues to be an active area of research, I wish this APOD had linked to a few more relevant articles, like this recent article in Science which basically claims the total susceptibility of the atmosphere is too small for this to really be a viable method to counter-act CO2 climate change.

https://www.science.org/doi/10.1126/science.abd3980

That's not what I read in that paper. It appears to say only that ship track data are a poor model for understanding the cloud response of anthropogenic aerosols. Not that clouds produced by aerosols don't have the potential to create a degree of cooling (which is not the same as counteracting climate change).