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Perennial rice: Plant once, harvest again and again

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Re: Perennial rice: Plant once, harvest again and again

#121

Post by kbelder »

lettergram wrote: post #117
matthewdgreen wrote: post #55

Earlier quoted context omitted.

Methane and CO2 are very different things. The former has a massively greater warming effect than the latter, and takes long enough to degrade in the atmosphere that it can significantly affect warming times. If you aren’t paying attention to the rising methane levels in our atmosphere (and possible evidence of a feedback loop) with serious trepidation, you’re a lucky person who probably sleeps well at night.

I want a warmer atmosphere. All the UN data points to a warmer atmosphere equating to more food and higher quality of life. I concede some concern about potential feedback loops, but the reality is that earth was and still is in an ice age. Ice ages are not the norm on earth, I think it’s okay if we exit an ice age. Yes things will change, but it’ll be over decades to millennia. We’re working on carbon capture right…

I somewhat agree. A climate several degrees warmer than recent history seems like it would be beneficial; in the past, warmer periods coincided with a lush and rich biosphere. More energy is available to life.

Like you, long-term, I'm more worried about the upcoming ice age than runaway global warming. We know how to fix global warming, and will in the next hundred years: Nuclear and solar.

But... warming can still be very disruptive in the short term. Coastlines moving a few hundred feet might be disastrous for entire regions. Staple crops failing in one nation and blooming in another may cause refugees, famine, and war. Politics is local.

Re: Perennial rice: Plant once, harvest again and again

#122

Post by slily »

lettergram wrote: post #115
Aromasin wrote: post #106

Earlier quoted context omitted.

To put this into context, animal agriculture is responsible for 18% of the worlds CO2 emissions, uses 83% of the world's farmland, but only produces 18% of our calories and 37% of our protein.

“Our protein” isn’t exactly fair. Depending on the culture meat can account for as much as 90%+ of protein.

Failing to control for nutritional quality also makes those numbers very misleading. For example that 37% of protein would translate to more than double that number based on bioavailability for humans, and meat is far more nutritious than grains (and many vegetables).

Re: Perennial rice: Plant once, harvest again and again

#123

Post by lm28469 »

xyzzyz wrote: post #84
crazygringo wrote: post #74

Earlier quoted context omitted.

> but this is of no practical consequence, because the methane will not accumulate year over year, like the emissions from fossil fuels do. Methane still takes 12 years to break down in the atmosphere, and it's more than 25 times as potent of a greenhouse gas than CO2. CO2 concentrations are currently ~420 ppm, while methane is ~1866 ppb, or 1.9 ppm. If we assume methane is 25 times worse than CO2, that 1.9 ppm is th…

Thank you for redoing the math I did, and confirming I was exactly correct with figures. The increase in concentration is observable, but the impact on climate is not. Again: this increase is similar to increase between 2000 and 2020. Without extremely careful and precise measurements, nobody would really be able to perceive any difference in climate between these two dates. This matters, because it is the perceived…

> this increase is similar to increase between 2000 and 2020. Without extremely careful and precise measurements, nobody would really be able to perceive any difference in climate between these two dates.

If that's how you work then nothing has any impact whatsoever, cars, planes, cattle, over twenty years if you split everything in sub categories they're all negligible

Meanwhile we clearly already can measure the effect of it all.

With your logic you're the proverbial boiled frog my friend...

Re: Perennial rice: Plant once, harvest again and again

#124

Post by _dark_matter_ »

lettergram wrote: post #115
Aromasin wrote: post #106

Earlier quoted context omitted.

To put this into context, animal agriculture is responsible for 18% of the worlds CO2 emissions, uses 83% of the world's farmland, but only produces 18% of our calories and 37% of our protein.

“Our protein” isn’t exactly fair. Depending on the culture meat can account for as much as 90%+ of protein.

or as little as 0%. The point stands.

Re: Perennial rice: Plant once, harvest again and again

#125

Post by lm28469 »

atleastoptimal wrote: post #43
chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

Damn is there any commodity crop that isn't an environmental disaster?

It's all about the scale and the method. When all we care about is productivity and profit we end up with that

Re: Perennial rice: Plant once, harvest again and again

#126

Post by lostlogin »

lettergram wrote: post #115
Aromasin wrote: post #106

Earlier quoted context omitted.

To put this into context, animal agriculture is responsible for 18% of the worlds CO2 emissions, uses 83% of the world's farmland, but only produces 18% of our calories and 37% of our protein.

“Our protein” isn’t exactly fair. Depending on the culture meat can account for as much as 90%+ of protein.

Or near zero percent.

Why isn’t this stat fair?

Re: Perennial rice: Plant once, harvest again and again

#127

Post by ericpauley »

lettergram wrote: post #115
Aromasin wrote: post #106

Earlier quoted context omitted.

To put this into context, animal agriculture is responsible for 18% of the worlds CO2 emissions, uses 83% of the world's farmland, but only produces 18% of our calories and 37% of our protein.

“Our protein” isn’t exactly fair. Depending on the culture meat can account for as much as 90%+ of protein.

I imagine they're using "our" in the global sense. Virtually no one is truly dependent on meat for protein; the food the livestock eat are probably mostly human-edible and offer sufficient protein on their own. There's minimal nutritional value added by the meat production process.

Re: Perennial rice: Plant once, harvest again and again

#128

Post by s1artibartfast »

crazygringo wrote: post #59
xyzzyz wrote: post #53

Earlier quoted context omitted.

Methane is worse, but it again doesn’t matter here, because the fields are in steady state not only with CO2, but with methane as well. Methane doesn’t linger in atmosphere forever, it decomposes into CO2 in a decade or so. This means atoms of methane emitted from the fields are pretty much exactly paired with atoms of methane in atmosphere decaying into CO2. This means that methane emitted from the fields doesn’t in…

That doesn't make sense mathematically. Because you could start with zero methane in the atmosphere, just lots of CO2, but the rice would introduce methane. Eventually yes you can get to a steady state of methane, but the point is that the more rice there is, the higher that steady state becomes. Which is bad. So the total amount of methane would absolutely increase. (And if you stopped planting rice at all it would…

I think they are right.

Yes, the more rice there is, the higher the steady state would be.

However, we aren't planting more rice. The ammount of rice grown and methane released is already in steady state.

This is a seperate point than if atmospheric methane would go down if we grew less rice than today.

Re: Perennial rice: Plant once, harvest again and again

#129

Post by t-3 »

crazygringo wrote: post #54
xyzzyz wrote: post #45

Earlier quoted context omitted.

> So, perennial rice may end up reduce GHG emissions substantially. Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere. They do not add additional GHG to the atmosphere the way burning fossil fuel do. When you burn fossil fuels, the carbon atoms released into atmosphere have been captured from the atmosphere millions years ago. When weeds and other organ…

Can you elaborate on this? Do you mean that rice plants are actually absorbing methane earlier on, so they're just releasing the same amount? Or are they actually producing methane from other molecules, like water and carbon dioxide? Because yes, methane breaks down in the atmosphere into H2O and CO2 so you could view it as a cycle, but the more rice there is the higher the steady state methane in the atmosphere is,…

The rice plants don't absorb or release methane, the breakdown of organic matter in the flooded ricefields causes the release of methane. In dry/unflooded fields, the decay would be much slower. The flooded fields possibly emit more methane and less CO2 than unflooded due to anaerobic conditions, but I'm just guessing.

Re: Perennial rice: Plant once, harvest again and again

#130

Post by matthewdgreen »

lettergram wrote: post #117
matthewdgreen wrote: post #55

Earlier quoted context omitted.

Methane and CO2 are very different things. The former has a massively greater warming effect than the latter, and takes long enough to degrade in the atmosphere that it can significantly affect warming times. If you aren’t paying attention to the rising methane levels in our atmosphere (and possible evidence of a feedback loop) with serious trepidation, you’re a lucky person who probably sleeps well at night.

I want a warmer atmosphere. All the UN data points to a warmer atmosphere equating to more food and higher quality of life. I concede some concern about potential feedback loops, but the reality is that earth was and still is in an ice age. Ice ages are not the norm on earth, I think it’s okay if we exit an ice age. Yes things will change, but it’ll be over decades to millennia. We’re working on carbon capture right…

Last summer we had heat waves and droughts on three continents simultaneously, plus massive unprecedented floods in Pakistan. It doesn't take much to destroy a year's worth of crops, and the IPCC modeling doesn't really come to grips with what we're seeing.
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