Climate change has turned permafrost into a carbon emitter
cbc.ca
cbc.ca
There is definitely a concern about multiple feedback loops involving methane from clathrates, permafrost and also wetlands. There's also considerable uncertainty about the origin of methane emissions. But as far as I can tell the methane "bomb" theory shouldn't be our major concern.
[1] http://www.realclimate.org/index.php/archives/2013/11/arctic...
Are there any stabilizing forces we know about? I only ever hear about these types of positive feedback loops, and it scares the hell out of me.
People have long thought the threshold to be around 2 degrees C, but now some are thinking it's more like 1.5. The CO2 level everybody agreed was safe was 350 ppm.
How different a place that new equilibrium is ... is open to debate and not really known. What climate scientists have shown is that it can be, and likely is, pretty bad.
Note that in the near term, the negative feedback of photosynthesis may be overwhelmed by changes in ecosystems: if the climate changes rapidly, whole forests may find themselves in a different biome, ocean circulation patterns may change, more freshwater may enter estuaries, etc. Plants evolve quickly, though, and most of their carbon sequestration is through algae and seaweed with short lifespans.
For example, the Australia tropical rain forest, which by it's definition is wet, never has to deal with fire.
But this year that change as some parts of the Australian rain forest experienced bush fires.
If that trend continues then those ecosystem will struggle to survive as they have not evolved to deal with fire on a regular basis.
This is probably cold comfort for the billions of people that will die.
increased temp > increased evaporation > increased cloud coverage which reflects more sunlight
increased co2 > increased tree growth
increased co2 > increased algae, plankton growth to absorb co2... other marine animals will also feed on these, increasing their mass, and when they die, they'll sink to the bottom, where they'll mostly remain.
increased co2 > increased diffusion into seawater.. clams, oysters, etc combine this carbon with calcium to produce shells.. and when they die, they accumulate on the sea floor eventually turning into rock.
Unfortunately, the fact that co2 in the atmosphere is growing indicates we're overwhelming these.. I take zero comfort in the fact that these exists.. it actually makes me nervous because once they reach their maximum, co2 will start growing even more rapidly.. and then it'll be so much worse.
increased co2 > increased diffusion into seawater - isnt acidity of the ocean increasing, making it more difficult for the shelled sea life to even develop?
But its lifetime in the atmosphere is very short; the evaporated water vapor condenses in the upper atmosphere into clouds and precipitation.
What longer term numbers I have seen indicate that the average water vapor content of the atmosphere has been roughly constant during the warming of the last half century or so.
We will probably get more water vapor in the future but most of the PWAT ends up in clouds. And that’s where the feedbacks get interesting, cloud height is very important to radiative balance and there are a couple of indirect effects to consider too.
Also increased evaporation > increased latent heat transport to upper atmosphere where it can more easily escape to space. According to the numbers in Kiehl & Trenberth's global energy budget, total latent heat transport is about 80 W/m^2, which means a 5 percent increase in it would entirely cancel out the increased radiative forcing from a doubling of CO2. This is a negative feedback that I don't see discussed much at all.
> the fact that co2 in the atmosphere is growing indicates we're overwhelming these
No, it doesn't, it just indicates different timescales for CO2 emissions vs. uptake.
>No, it doesn't, it just indicates different timescales for CO2 emissions vs. uptake.
It's not clear to me what the distinction is you're trying to make here? If the time scale for emissions vs. uptake is different such that emissions are exceeding uptake capacity due to the different timescales, isn't the previous comment correct?
If the uptake timescale is longer, uptake will catch up to emissions over time (I realize I didn't make that sufficiently clear in my previous post), so CO2 growth does not indicate that uptake has reached "maximum", which is what the post I responded to was claiming.
Then I don't understand where you're coming from?
I never said that, and I don't think it's true. The timescale I was referring to is the timescale for uptake capacity to respond to a change in CO2 levels. For example, trees grow and reproduce more slowly than CO2 levels have been changing, so the increase in uptake from tree growth and reproduction takes some time to respond to an increase in CO2. But that doesn't mean it never responds. It does; uptake capacity does increase.
This indicates to me I probably need to go away and do some research.
Thanks for bringing this assumption to my attention.
If this continues, we'll hit 420ppm within a couple years, 430ppm maybe 4 years after that, over 440ppm if not nearing 450ppm by the end of the 2020s with no slowdown in sight.
Truly, truly alarming.
My concern is, if we stop polluting the environment and the global dimming is stopped, then climate change will get much worse.
Global Dimming might explain why the climate hasn't changed as much as some would expect.
(EDIT: Apparently sale is not finalized)
Also, I have no idea, but what is the timeline for ocean's rising to make a place like his on beach uninhabitable? I thought it was much less time, like 12 years or so, there are so many predictions out there.
It's the people who aren't rich who have to worry the most--the people that have most of their wealth tied up in their house, and so need to be able to sell it for a good price to afford to move.
You may be thinking of the windstorm insurance program. The state of Florida underwrites that, and started it as insurance of last resort after insurers started bailing following Andrew.
Insurers and the Pentagon seem to be treating it as a real threat, which is probably more indicative than the purchasing habits of people who tend to love rapidly depreciating status symbols.
I don't know about you, but I don't sweat what happens to my investments after myself and my children are long gone. Honestly, most of the time I have trouble just planning ten years out.
Here is a 2019 paper on the critical role of clouds in arctic cooling https://www.nature.com/articles/s41598-019-44155-w#Sec7
https://www.carbonbrief.org/tropical-forests-no-longer-carbo...
"... the research didn't measure methane, a greenhouse gas about 30 times more potent than carbon dioxide that is also released from soil."
> rot
That's what the previous comment just said.
Decomposition of plant matter occurs in many stages. It begins with leaching by water; the most easily lost and soluble carbon compounds are liberated in this process. Another early process is physical breakup or fragmentation of the plant material into smaller bits which have greater surface area for microbial colonization and attack. In smaller dead plants, this process is largely carried out by the soil invertebrate fauna, whereas in the larger plants, primarily parasitic life-forms such as insects and fungi play a major breakdown role and are not assisted by numerous detritivore species.
https://en.wikipedia.org/wiki/Decomposition#Plant_decomposit...
Although I think carbohydrates is probably more accurate if we’re talking about decaying plant matter.
Lignin is also not normally considered a carbohydrate.
No, but when we say "carbon emitter", we're talking about methane and other alkanes... and CO2.
CH4 is itself a greenhouse gas that is more potent than CO2 in the short term... and then it decays to water vapor and CO2 in reactions with radicals in the upper atmosphere.
So, it's overall somewhat worse than CO2 in the short term (since it's not just CO2), and equivalent in the long term?
For example, the news earlier this year about treeplanting, spoke about removing Carbon from the atmosphere. Typically, the GHG's will be rolled up into either CO2e (CO2-equivalent) or just C. In the latter case, you often just have to do some molar math to get the CO2e from C.
The CBC gets $2 BILLION/yr from the Trudeau Liberal government. All other private news orgs have a hand in a $600 Million/yr pot. For example, the Toronto Star alone receives $5.2 Million/yr from the Canadian federal government.
We can all agree this is a bad system apt to produce favourable results for the Liberals. For example, they won re-election on Monday.
Or Andrew Scheer is completely out of step with 2019.
Also, there will never be another typical Conservative majority due to mass migration. The Liberals bring 1 million Liberal-voting migrants per year into Canada. The population of which is 35 million. Simple math.
But none of this invalidates my argument that the Canadian media system is broken.