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Climate Change in a Nutshell: The Gathering Storm [pdf]

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Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#111

Post by Comevius »

robotrout wrote: post #107
Comevius wrote: post #99

Earlier quoted context omitted.

"There are many scientists that believe solar forcing is responsible" The solar constant in the past 400 years has varied less than 0.2 percent. "It is well known that cosmic rays effect cloud formation." Not well known, because the research is still ongoing. Henrik Svensmark's research in a dust- and impurity-free atmosphere contributed to our understanding of aerosol microphysics, but others agree that the effect i…

From your quoted article. This work offers a new understanding of global particle formation as based almost entirely on ternary rather than binary nucleation, with ions playing a major but subdominant role. Our results suggest that about 43% of cloud-forming aerosol particles in the present-day atmosphere originate from nucleation This is a major effect, confirmed by your own article. I'm not certain why you linked i…

I don't know why I linked it if you just end up making your very own conclusions.

This paper is part of the CERN CLOUD project (http://cloud.web.cern.ch/), an experiment trying to model our atmosphere to find out how much aerosols affect cloud formation and climate change.

The conclusion so far is that cosmic rays can charge aerosol particles, and produce big enough particles to contribute to cloud forming. This represents less than 10% (several per cent) of the total particle formation from nucleation, a major, but subdominant role. Nucleation (the creation of big enough particles) itself plays a 43% role, the rest is particles already in the atmosphere. So cosmic rays is less than 10% of 43%.

In any case if cosmic ray created aerosols would have such a large effect on clouds, so would other aerosols, such as those from air pollution.

Clouds themselves play a less than 10% role in climate change, so it's like 10% of the 10% (cosmic ray nucleation) of 43% (nucleation), as I said a tiny effect. Clouds also not just trap heat, but reflect sunlight back, cooling the planet.

As Ken Carslaw, one of the authors of the paper suggested: "It’s a tiny effect and previous studies suggest it will not be important". https://cosmosmagazine.com/climate/cosmic-ray-theory-of-glob...

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#112

Post by randyrand »

mr_overalls wrote: post #95
randyrand wrote: post #89

Earlier quoted context omitted.

People will primarily move more inland within their own countries. Some cities will be raised. Neighboring countries will absorb some. Small border shifts may happen, as have happened for centuries.

You have no reason to believe this. From: https://www.esquire.com/news-politics/a25422366/trump-ambass... "The fourth and latest National Climate Assessment put together by 300 scientists from 13 agencies of the U.S. government and released last month found that climate change is real, man-made, and will cost the U.S. 10 percent of its economy by 2100. Midwestern farmers will lose 75 percent of their crop yields, and…

"Midwestern farmers will lose 75 percent of their crop yields"

and other farmers will benefit and have increased yeilds. I don't mind facts. But misleading ones I do mind.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#113

Post by Brakenshire »

nabla9 wrote: post #97
Brakenshire wrote: post #92

Earlier quoted context omitted.

One thing I’d be interested to read is the difference between 1.5C and, say, 2.5C of warming. Do you know of any reports (or maybe just part of the IPCC reports) which lay out the incremental risks? I just read for instance an editorial from nature which said that 10-30% of coral reefs survive at 1.5C but none survive at 2C. I’d like more of that kind of information to understand the risk profile.

carbonbrief.org has interactive comparison between 1.5C, 2C and 3C. https://interactive.carbonbrief.org/impacts-climate-change-o...

Perfect, sincerely thank you for the link.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#114

Post by ilove_banh_mi »

yongjik wrote: post #102
ilove_banh_mi wrote: post #87

Earlier quoted context omitted.

Provocatively worded... but intriguing from an engineering POV: if it is too late to limit CO2 levels and return to pre-industrial levels, what levers do we have to control water vapor levels?

Nothing. Water vapor is always in equilibrium with oceans on the timescale of weeks. In other words, any excessive water vapor you manage to put into the atmosphere will simply rain down. http://www.realclimate.org/index.php/archives/2005/04/water-...

Not so fast, please. The very link you provide refers to the Pinatubo eruption that caused a significant multi-year cooling. It is well-known that cloud albedo changes in response to the addition of aerosols, which ultimately changes cloud water content (rapidly adjusting equilibrium with changes in global sea-surface temperature). Thus, there is at least one lever of action that we know of.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#115

Post by Symmetry »

vladimirralev wrote: post #84
Symmetry wrote: post #61

Earlier quoted context omitted.

Would you be willing to play Russian Roulette with a revolver with four bullets in the chambers just because there's uncertainty about whether the gun would go off when you pulled the trigger? Yes, there's a chance that climate change is going to no big deal. The most likely future occurrence is that things go the way the sober scientists at the IPCC give in their median prediction - a disaster but an eminently manag…

Just watch the video. They talk about all of this. I don't understand why I am getting so many nasty comments especially when those points are addressed in this video. Both guys are serious scientists and respect each other while feeling completely embarrassed by the zealots. You talk about the russian roulette with climate, but the issue is far more complicated. There are bunch of other russian roulettes to consider…

Ok, I finally watched the video and I don't think it was worth my time at all. It was nice that they were polite to each other but really we have understood the basics of how increased C02 causes global warming for about a century. Current detailed climate models are kind of crap, Nate Silver went into why in some detail in his book on modeling, The Signal and the Noise, which I recommend but that doesn't change the anything I said in the above post - climate models are as likely to undershoot the dangers of warming as they are to overshoot them. Christy basically seemed to be arguing that there's uncertainty so he was permitted to believe what he wanted to. That's not a rational way to approach problems, especially given how he exaggerated the nature of the uncertainty.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#116

Post by ilove_banh_mi »

Comevius wrote: post #103
yters wrote: post #56

Earlier quoted context omitted.

This is an interesting question. Haven't there been much warmer periods in our planet's history that were followed by an ice age? It is hard to sort out exactly what climate change means.

Those warming periods are either local, are much, much slower and they are not supposed to be in sync with human activities either. This one is much faster. Not everyone sees it of course. Change blindness is what they call it. https://www.npr.org/sections/krulwich/2014/02/05/257046530/b...

This is not a correct description of past climate changes. The glacial and interglacial periods of the last 2.5 million years have been global and swinging temperatures by 6-9°C in either direction, with periods between 40-100k years.

During the last interglacial (Eemian, ca. 129–116k years ago) sea level was 6-9 meters higher than today; Scandinavia was an island. The water temperature of the North Sea was about 2°C higher than at present; hippos lived as far North as the Rhine and the Thames. The onset of the Eemian took just a few centuries, during which global temperatures shot up >5°C.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#117

Post by robotrout »

Comevius wrote: post #111
robotrout wrote: post #107

Earlier quoted context omitted.

From your quoted article. This work offers a new understanding of global particle formation as based almost entirely on ternary rather than binary nucleation, with ions playing a major but subdominant role. Our results suggest that about 43% of cloud-forming aerosol particles in the present-day atmosphere originate from nucleation This is a major effect, confirmed by your own article. I'm not certain why you linked i…

I don't know why I linked it if you just end up making your very own conclusions. This paper is part of the CERN CLOUD project ( http://cloud.web.cern.ch/ ), an experiment trying to model our atmosphere to find out how much aerosols affect cloud formation and climate change. The conclusion so far is that cosmic rays can charge aerosol particles, and produce big enough particles to contribute to cloud forming. This re…

Even if we were to stipulate his 10% number, that's 4.3% of cloud formation based on cosmic rays. Not insignificant.

Your repeated contention that pollution aerosols are of equal magnitude to cosmic rays contribution requires a large helping of evidence to back it up, given the huge quantity of cosmic rays that impact the troposphere.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#118

Post by notacoward »

strict9 wrote: post #2

Skimmed through this, but I can't make it all the way. It's so jarring and too depressing. I lump climate change deniers into the same category as flat-earthers. Although I have more respect for the latter, as at least they aren't blindly swallowing self-serving nonsense spewed by ignorant politicians and certain news outlets.

> I lump climate change deniers into the same category as flat-earthers.

At least the flat-earthers are harmless. The climate-change deniers are preventing necessary action on issues of life and death.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#119

Post by notacoward »

randyrand wrote: post #51

I've long been in the camp that we worry about climate change more than makes rational sense. I'm not saying we should ignore it, but we often overstate. It's worth remembering that the effects on QoL will be completely eclipsed by technological progress within that period and that the timescales that GW happen over (50+ years) are long enough that most people will hardly ever notice it. Gradual relocation will be ou…

> Gradual relocation will be our primary means of fighting it.

That highlights what's wrong with your PoV. If sea-level rise were the only issue, your comment might actually make some sense ... but that's not the case. Climate change will also lead to droughts, floods, famine, conflicts over water, species extinction, possible collapse of entire ecosystems, and a host of other ills too numerous to mention. Normal technical progress isn't going to solve biodiversity problems we barely understand, or human-society problems that will be driven by warming. It would require a major leap on par with the birth of atomic physics or molecular genetics. Maybe more than one. You want to talk about what's rational? Faith in the modern equivalent of miracles is not rational.

Re: Climate Change in a Nutshell: The Gathering Storm [pdf]

#120

Post by jimjimjim »

randyrand wrote: post #89
Brakenshire wrote: post #88

Earlier quoted context omitted.

If the world was composed of countries living at the quality of life of Western Europe or America and with that level of technical and economic expertise this would I think be reasonable, but in fact billions of people are living hand to mouth. Look at the effect that Syrian migration to Europe or indeed Mexican migration to the USA has had on Western politics. Now imagine instead of 5 million people from Syria 100 m…

People will primarily move more inland within their own countries. Some cities will be raised. Neighboring countries will absorb some. Small border shifts may happen, as have happened for centuries.

what what what? that is a nightmare scenario.

If anything like countries needing to move inland happens it will mean that the world is already in economic ruin and the survivors are in a roadwarrior/madmax style existence.

if this needs to happen, the world will in a such a state that YOU will not be able to buy a beer or watch tv.

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