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Messages - CDN_dude

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Consequences / Re: Places becoming less livable
« on: August 25, 2018, 04:29:01 PM »
A freshwater shortage crisis in an unusual place. Iqaluit could soon run out of water:

Consequences / Re: Conservative Scientists & its Consequences
« on: August 14, 2018, 10:06:42 PM »
Arctic understanding limited by patchy field work, scientist says. Areas of Canadian Arctic poorly sampled, could mean faulty assumptions about rate of climate change

"Metcalfe's research suggests scientists are oversampling locations warming slowly, while places warming much more rapidly, such as the Canadian Arctic, may be releasing stored carbon at a greater rate and in a greater quantity than assumed.

Metcalfe says this could mean scientists are underestimating the global impact of warming in the Arctic."

Consequences / Re: Conservative Scientists & its Consequences
« on: August 12, 2018, 09:23:16 PM »
Open-access paper "Wildfire as a major driver of recent permafrost thaw in boreal peatlands"

"Permafrost vulnerability to climate change may be underestimated unless effects of wildfire are considered. Here we assess impacts of wildfire on soil thermal regime and rate of thermokarst bog expansion resulting from complete permafrost thaw in western Canadian permafrost peatlands. Effects of wildfire on permafrost peatlands last for 30 years and include a warmer and deeper active layer, and spatial expansion of continuously thawed soil layers (taliks). These impacts on the soil thermal regime are associated with a tripled rate of thermokarst bog expansion along permafrost edges. Our results suggest that wildfire is directly responsible for 2200 ± 1500 km2 (95% CI) of thermokarst bog development in the study region over the last 30 years, representing ~25% of all thermokarst bog expansion during this period. With increasing fire frequency under a warming climate, this study emphasizes the need to consider wildfires when projecting future circumpolar permafrost thaw."

It's since been made open-access

Science / New paper by Steffen et al on Climate System Tipping Points
« on: August 07, 2018, 04:19:30 PM »

Paper is here, now open access

The team considered ten feedbacks--"permafrost thaw, loss of methane hydrates from the ocean floor, weakening land and ocean carbon sinks, increasing bacterial respiration in the oceans, Amazon rainforest dieback, boreal forest dieback, reduction of northern hemisphere snow cover, loss of Arctic summer sea ice, and reduction of Antarctic sea ice and polar ice sheets"--and found that even if human emissions only push the temperature up to 2 C, the feedbacks could still push the global temp eventually up to 4-5 C, with sea levels eventually (doesn't say when) reaching 10-60 metres.

In other words, the tipping point for a runaway warming, Hothouse Earth may be as low as 2 C above pre-industrial when all feedback loops are taken into account. 

With the humidity, we hit a high of 42 C today here in central Ontario. So much for the Great White North, eh.

Consequences / Re: Near Term Human Extinction
« on: May 31, 2018, 08:21:43 PM »
Paladiea, you might find Jeremy Jackson, of the Scripps Institute, an interesting speaker on these kinds of topics to do with the health of the oceans.

I'm sure it will be too lefty and optimistic for some on here but I enjoyed the French doc called Demain (Tomorrow in English).

Consequences / Re: Near Term Human Extinction
« on: May 18, 2018, 05:54:55 PM »
Forest Dweller, I'm glad to see your post because it touches on a lot of my own feelings. When I look at the graph of CO2 and see the spike starting in the Industrial Revolution, it's impossible for me to conclude anything other than that this entire era has been one enormous historical error. One way to correct it would be for our Western societies to admit that we have made a mistake. This would involve admitting that the Indigenous peoples we displaced here in North America were right all along however, making it unlikely such a recognition of our error will ever take place at the deep level it needs to in order for our practices to truly change. The lack of recognition of how deep the errors in our thinking go leads to things like sustainable development, the have cake and eat it approach. We need a philosophical revolution similar to the Enlightenment, which will lead to a new ethic that values nature. Changes in practices can only follow from a change in thinking, and we are still not there yet despite everything you hear.

Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: May 16, 2018, 06:43:39 PM »
This was posted in the Wildlife section, but contains dire consequences for the ocean and food as well. From March, a UN report on biodiversity has dramatic negative consequences for food security in Asia: "...the risks posed by biodiversity loss should be considered on the same scale as those of climate change, noted the authors of the UN-backed report, which was released in Medellin, Colombia on Friday.

Among the standout findings are that exploitable fisheries in the world’s most populous region – the Asia-Pacific – are on course to decline to zero by 2048; that freshwater availability in the Americas has halved since the 1950s and that 42% of land species in Europe have declined in the past decade."

The rest / Re: Empire - America and the future
« on: May 15, 2018, 07:54:46 PM »
A potential conflict is brewing in the Red Sea region over water, specifically that of the Nile. One of several potential areas of tension that are not getting much mainstream attention, as this article argues:

Thought it was interesting to see this as a climate change impact as well. Countries are getting concerned about Egypt getting all the water now that increased droughts are projected. A sign of worse to come, no doubt.

The rest / Re: Human Stupidity (Human Mental Illness)
« on: May 05, 2018, 08:13:58 PM »
Interesting argument, posted recently also by Climate State, from a Cornell engineering professor who blames the shale gas revolution in the U.S. for a significant contribution to emissions, in large part because the amount of methane lost in the overall process has been underestimated, making it worse than coal. He goes into detail in the video at the bottom of this article.

Policy and solutions / Re: Coal
« on: April 12, 2018, 05:19:36 AM »
Australian company wants to recommission coal-fired power plant in order to power...bitcoin mining!? Yes that's right, a match made in hell: the world's worst energy source matched with its dumbest energy use. Hopefully they fail and go out of business early and fast:

Consequences / Re: Near Term Human Extinction
« on: February 26, 2018, 04:24:04 AM »
El Cid, what about the prospect of declining crop yields in key agricultural areas of the world, as are projected. What about this graph of projected precipitation in one of the world's breadbaskets, the Western North American region

I do not want to be the Pollyanna here, but from what I have seen in regenerative agriculture I conclude:

1. Sequestering Carbon into the soil is a difficult but viable way and I think that if we really started working on it, the potential is much bigger than current scientific papers project.
2. The good thing about soil with higher C (OM) content is that you need much less water as the water holding capacity of the soil increases by a lot, so you are more drought-resistant
3. And as surprising as it is, plants are generally "healthier" and more able to withstand cold or heat waves.

So I believe that regenerative agriculture will be one of the most important ways in the next decades that will help us feed mankind and at the same time reduce the atmosheric Co2.
I do think it is totally possibble to feed all of us at least until 2050-70 even under RCP8.5 scenario. With no hunger, no collapse in civilization.

My only great worry is Africa, where populations are projected to quadruple by 2100 from 2000 levels. It could lead to famine, wars and mass migration on a grand scale that could disrupt not only that continetn but others as well.

Ok, sustainable ag is really not my area, so those were genuine questions. Thanks for your response. I do agree with your last point that other conflicts in society may inhibit stable food production apart from the more direct impact of climate/weather. Regenerative ag could be a boon for politically stable societies, the question is, how many of those will remain going forward? Also, if we think of this issue as just food in general, there are other issues, like the decline of fish and salinization of rice paddies etc. that could be very disruptive in Asia. Anyway, regarding the subject of this thread, I do not believe that the challenges in food production will lead to our extinction, which I probably should have been more clear about. But high food prices, increased famine across Africa and parts of Asia, will lead to huge social strife, which is bad enough.

Consequences / Re: Near Term Human Extinction
« on: February 22, 2018, 12:17:33 AM »
As for extinction, the reason that won't happen is because rapid population decreases are a kind of negative feedback. Eventually we would get back to close to the carrying capacity of the Earth, even if at that point there were only say a million people left alive worldwide. The only real threat of total extinction I can think of is abrupt global warming combined with some kind of mega-pandemic for which there is no cure. Climate change alone won't do it.

Consequences / Re: Near Term Human Extinction
« on: February 22, 2018, 12:12:59 AM »
El Cid, what about the prospect of declining crop yields in key agricultural areas of the world, as are projected. What about this graph of projected precipitation in one of the world's breadbaskets, the Western North American region

I personally find it laughable to think that humans can go extinct this century, but at the same time, the possibility up to a billion may die is far from remote, indeed even likely under BAU.

Consequences / Re: Conservative Scientists & its Consequences
« on: January 26, 2018, 10:41:54 PM »
ASLR, thanks for your response. I agree I probably could have chosen my words more wisely there.

Also, an article from Michael Mann expressing some of his reservations about the methodology of the Cox study, as well as the way it was covered by the media:

Consequences / Re: Conservative Scientists & its Consequences
« on: January 25, 2018, 11:57:14 PM »
It seems to me that we are pretty much screwed, if the conclusions of even some of these studies prove correct. For instance, at 1.5 C it has been theorized the permafrost reaches a threshold beyond which it will begin to release carbon equivalent to a doubling of pre-industrial CO2, all on its own (study here as discussed in this thread,36.0.html.) So an additional 280ppm, over maybe a few centuries (not sure of the timeline). That gives us a bare minimum of 680ppm. (~400 today plus the 280. And of course we have more than 400 baked in already for the near future). Now, if it also proves true that the increase in Arctic precipitation falls mostly as rain rather than snow, (post #2109) we get another increase equivalent to a doubling of carbon, so another 280. That puts us at 960ppm. So then take that absolutely conservative (assuming these two studies I have cited prove correct) baseline and add all of the other positive feedbacks you believe are likely.

Hoping someone can show where I have erred. The sheer number of additional positive feedbacks I'm not including here is frightening. Consider for instance that the conditions for survival of the plankton who produce 50% of our oxygen are also jeopardized by ocean acidification and hypoxia. So the question is, are we now too late?

Consequences / Re: Health Effects of Climate Change
« on: January 18, 2018, 02:51:16 AM »
Contra the EPA's claim that unclean air is good for you, an important new study finds that elevated CO2 levels have a direct negative effect on human cognition.

This is of particular concern since Co2 levels inside buildings are highly elevated compared to outside. Furthermore, the threshold at which impacts start to occur is unknown but may be as low as 600ppm! A figure we are on track to achieve everywhere in the world by the end of the century.

Consequences / Re: Oceanic anoxia
« on: January 12, 2018, 04:09:23 AM »
I know Petrovskii has done some initial work on this issue. I'm not aware what the critical reception to his papers has been however. Here is an open access version of his most recent:

"We show that, when the temperature rises sufficiently high, a regime shift happens: the sustainable oxygen production becomes impossible and the system's dynamics leads to fast oxygen depletion and plankton extinction."

I've also found that Jeremy Jackson of Scripps has some good interviews that help explain the crises oceans are facing (for non-experts):

Consequences / Re: Conservative Scientists & its Consequences
« on: November 23, 2017, 03:35:48 AM »
Actually, it wasn't...

Ok thank you, you've done a much better job at putting that in context than the article. One of the perils as a non-scientist of relying too much on science journalism I guess.

Consequences / Re: Conservative Scientists & its Consequences
« on: November 22, 2017, 06:18:20 PM »
Probably not fair to call this an instance of conservative scientific reticence since it is a new discovery, but it is another addition to the list of feedbacks not currently included in climate models.

"In the journal Nature Communications, researchers at The Ohio State University and their colleagues describe the discovery of the first known methane-producing microbe that is active in an oxygen-rich environment...
"We've always assumed that oxygen was toxic to all methanogens," said Kelly Wrighton, project leader and professor of microbiology at Ohio State. "That assumption is so far entrenched in our thinking that global climate models simply don't allow for methane production in the presence of oxygen. Our work shows that this way of thinking is outdated, and we may be grossly under-accounting for methane in our existing climate models."
...the researchers found traces of Candidatus Methanothrix paradoxum in more than 100 sites across North America, South America, Europe and Asia."

Read more at:"

Permafrost / Re: Modelling permafrost carbon feedback
« on: November 16, 2017, 03:16:16 AM »
In this video Miriam Jones of USGS provides a good overview of some research on methane and carbon release from permafrost thaw, touching on thermokarst lakes and also how rapid the release of carbon is once thaw is underway. A very clear and straightforward presentation with Q&A:

Science / Re: 2017 Mauna Loa CO2
« on: November 13, 2017, 06:06:40 PM »

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