[pcm81]

Living in FL i hear every day about the huge seagrassum that is starting to wash ashore here in FL. The thing is, this thing is thousands of miles wide and millions of tons in weight floating around Atlantic ocean. It is now a nuisance for coastal communities in FL, Bahamas and nearby beaches. Every year it grows bigger and bigger due to nitrogen fertilizer that is washed off into the ocean as well as elevated global temperatures. BUT i wonder if there is a silver lining to this effect. To glow it still needs carbon, which it will get from CO2 that is dissolved in water or air, since parts of it float on surface. So, i wonder if this huge plant in the Atlantic ocean could actually get large enough to clean up the earths atmosphere of elevated levels of CO2?

[Borek]

I wonder what is the time scale here - it definitely binds the CO₂, but for how long? After all it not only grows, it also dies and decomposes.

Other than that comparing dry mass of what is grown every year (if such data exists) with carbon dioxide emissions shouldn't be that difficult, sounds like a simple stoichiometric problem (estimate only, but at least will tell something about orders of magnitude).

[pcm81]

I wonder what is the time scale here - it definitely binds the CO₂, but for how long? After all it not only grows, it also dies and decomposes.

Other than that comparing dry mass of what is grown every year (if such data exists) with carbon dioxide emissions shouldn't be that difficult, sounds like a simple stoichiometric problem (estimate only, but at least will tell something about orders of magnitude).

After a bit of googling, i see research papers talking about sea grass marshes that are being proposed as storage for carbon. Numbers like 35x faster that rain forest for absorption rates are cited. But this thing being a floating mass, rather sea floor bound grass may have different properties. Availability of carbonates in sea water being sited as a factor in rate of carbon absorption by sea grass... Now, this thing being a floating body may have an increased absorption, since it can float to a new area with higher concentration of carbonates.

Edit: I wonder how many of current coal deposits came from sea floor from long ago rather than dry land forests and grass. These sea born coal beds may give an indication for carbon capture potential of sea grasses.

[Borek]

Edit: I wonder how many of current coal deposits came from sea floor from long ago rather than dry land forests and grass. These sea born coal beds may give an indication for carbon capture potential of sea grasses.

Interesting question, don't remember seeing remains other than land animals/plants in coal.

Several years ago I visited a lignite open pit mine. In some places you could still smell forest terpenes.

[Enthalpy]

If said seagrassum can serve to feed cattle or to fertilize fields, then there is an economic incentive to harvest it, and you'll get rid of it.