Climate models are running red hot, and scientists don’t know why • Hacker News Board

Re: Climate models are running red hot, and scientists don’t know why

#121

Post by protanopia » Mon, Feb 03, 2020, 4:07 PM UTC

IanSanders wrote: post #40

lbsnake7 wrote: post #30

I’m a climate change skeptic almost entirely because I don’t trust models. I believe there are too many dynamic things happening in the world for anyone to be able to predict accurately say the next 100 years (solar, earthquakes, volcanoes etc). One way to make me a believer though is an experiment: if I were to give you a 100 year stretch of history and you were able to accurately predict with the models what exactl…

There being no accurate model doesn't imply climate not changing

But is does imply that implementing specific policies to counteract what specific models predict might not be the best idea.

Re: Climate models are running red hot, and scientists don’t know why

#122

Post by coldpie » Mon, Feb 03, 2020, 4:08 PM UTC

0xffff2 wrote: post #52

giarc wrote: post #29

If you are like me, you hate reading articles like this. You know there is a problem but you feel like you can't do anything about it. You recycle, you turn off lights, you have a programmable thermostat but you know it's a drop in the ocean. I finally decided to do something about it last fall. I researched and have committed to purchasing green power. Every month I purchase 850 kWh for $22 from Bullfrog Power (a Ca…

There is a problem and you can't do anything about it. We are way past the point where individual action is going to cut it. You have to vote. No other action is going to have a meaningful impact and you shouldn't pretend otherwise because it makes you feel better about yourself.

You're right that individual action isn't enough. But individual action does also have an impact. Commuter cars and SUVs (not airplanes, not shipping trucks) are the largest single source of carbon emissions in the US[1], accounting for about 15% of all US carbon emissions[2]. If just 1 in 10 commuters switched to taking public transit instead of driving, that alone would drop US emissions by 1.5%. If public transit became the default method for most transportation, we could realistically lop off 7-10% of US emissions. These are individual choices. It's true local and federal governments could do more to encourage using public transit, but most of that action would be driven by increased demand, which comes from individuals.

Don't fall into the trap that there's no reason to change your own habits because you think individual action doesn't matter. It does. But you're also right that it isn't enough.

[1] US EPA, 2017, "The transportation sector generates the largest share of greenhouse gas emissions. ... The largest sources of transportation-related greenhouse gas emissions include passenger cars and light-duty trucks, including sport utility vehicles, pickup trucks, and minivans. These sources account for over half of the emissions from the transportation sector." https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emis...

[2] Same source, 29% of emissions from Transportation; more than half that from commuter cars.

Re: Climate models are running red hot, and scientists don’t know why

#123

Post by chipsa » Mon, Feb 03, 2020, 4:08 PM UTC

SketchySeaBeast wrote: post #49

giarc wrote: post #29

If you are like me, you hate reading articles like this. You know there is a problem but you feel like you can't do anything about it. You recycle, you turn off lights, you have a programmable thermostat but you know it's a drop in the ocean. I finally decided to do something about it last fall. I researched and have committed to purchasing green power. Every month I purchase 850 kWh for $22 from Bullfrog Power (a Ca…

> If in 40 years, my kids ask me what I did to prevent climate change, I feel like I'll have an answer I'll be proud of. Doesn't it kind of feel like this is the equivalent of a kid in the 70's asking why their parents didn't stop World War 2? We absolutely need to be as vocal as possible, but as individuals, outside of trying to get people with power to affect the change we need, I don't know what we can expect to a…

Why would we have wanted to stop WW2? WW2 was an objectively good war for the Allies to fight (not that the Allies had a choice, as it only takes 1 side to start a war).

Re: Climate models are running red hot, and scientists don’t know why

#124

Post by Certhas » Mon, Feb 03, 2020, 4:08 PM UTC

protanopia wrote: post #69

orev wrote: post #37

Earlier quoted context omitted.

Tweaking the inputs would help one to identify what factor is causing the difference, which allows you to focus on that. It doesn’t mean you permanently leave it out. And it does not make a credibility issue. This is how science works — it is a process that strives to be as accurate as possible, not come up with a static answer and stick to it (that’s what religion does). The ability for science to change and adapt i…

It certainly does hurt the credibility of people saying we need drastic changes now based upon the models. If the answer might change next year, then making a drastic change based upon the current projections seems foolhardy.

FUD. The statement that we need drastic changes is not dependent on the details of the projection and is not based on it. Further, climate models have correctly predicted the heating we have already caused.

We have known the rough level of the climate sensitivity (delta T per doubling CO2) in the current macro state for decades. We have observed it. This science is incredibly settled. We don't know where the tipping elements are and we don't know how the impacts will be distributed.

Questioning the credibility of people calling for action might look like you are being the circumspect and rational one, asking for action proportionate to the evidence. In reality you are endorsing an ignorant position that ignores the evidence we have. If this is not wilful ignorance then please read up on this. The IPCC report summary is a good spot to start. Sceptical Science also often provides good writeups: https://skepticalscience.com/climate-sensitivity.htm

The fundamental physics that drive the sensitivity are straightforward. Energy balance and water vapour. That gets you a ballpark figure that is confirmed by the last 100 years of emissions.

Re: Climate models are running red hot, and scientists don’t know why

#125

Post by giarc » Mon, Feb 03, 2020, 4:09 PM UTC

Accujack wrote: post #81

giarc wrote: post #29

If you are like me, you hate reading articles like this. You know there is a problem but you feel like you can't do anything about it. You recycle, you turn off lights, you have a programmable thermostat but you know it's a drop in the ocean. I finally decided to do something about it last fall. I researched and have committed to purchasing green power. Every month I purchase 850 kWh for $22 from Bullfrog Power (a Ca…

Not to rain on your parade, but programs like this from big power companies are essentially meant to allow customers to feel good while simultaneously not going through the work and cost of switching completely to renewable power. That's because the power companies want to keep people from developing competition to them... if enough individuals install solar plants with battery storage, eventually they power company…

Bullfrog Power isn't a power company. They invest in green energy projects. https://www.bullfrogpower.com/green-energy/projects-and-sour...

Re: Climate models are running red hot, and scientists don’t know why

#126

Post by WhompingWindows » Mon, Feb 03, 2020, 4:11 PM UTC

lbsnake7 wrote: post #30

I’m a climate change skeptic almost entirely because I don’t trust models. I believe there are too many dynamic things happening in the world for anyone to be able to predict accurately say the next 100 years (solar, earthquakes, volcanoes etc). One way to make me a believer though is an experiment: if I were to give you a 100 year stretch of history and you were able to accurately predict with the models what exactl…

Even if you ignore the statistical forecasting models, look at the natural disasters occurring every season, and the massive changes happening in glaciers and arctic regions. Forget future projections, what's wrong with acknowledging many historical records are being smashed here and now? Isn't that evidence of climactic change to you?

Re: Climate models are running red hot, and scientists don’t know why

#127

Post by giarc » Mon, Feb 03, 2020, 4:11 PM UTC

lllr_finger wrote: post #41

giarc wrote: post #29

If you are like me, you hate reading articles like this. You know there is a problem but you feel like you can't do anything about it. You recycle, you turn off lights, you have a programmable thermostat but you know it's a drop in the ocean. I finally decided to do something about it last fall. I researched and have committed to purchasing green power. Every month I purchase 850 kWh for $22 from Bullfrog Power (a Ca…

That's awesome and I'm right there with you on wanting to do more. Have you considered your next step, and do you have any suggestions? Purchasing green power is such a minor sacrifice for my household, I'm still looking for something more.

My next steps will be writing to my government representatives. I live in Alberta and we just elected a right wing party that scrapped our carbon tax (although we now have a federal carbon tax).

Re: Climate models are running red hot, and scientists don’t know why

#128

Post by andersha » Mon, Feb 03, 2020, 4:11 PM UTC

_9hey wrote: post #99

I'd like to know others' thoughts on this talk/discussion https://www.ted.com/talks/allan_savory_how_to_fight_desertif...

legit. He's trying to mimic nature and keep the photosynthesis running by using ruminants to speed up the decomposition of organic matter and by timely management, have the regrowth sequester more atmospheric CO2 without overgrazing and compromising the grass plant or ecosystem.

Re: Climate models are running red hot, and scientists don’t know why

#129

Post by samatman » Mon, Feb 03, 2020, 4:12 PM UTC

I'm reminded of Feynman's famous anecdote about the Millikan oil drop experiment: Millikan underestimated the charge of the electron, and over the ensuing years, subsequent measurements slowly but surely converged on the correct value.

Why? Because experimenters who got the correct value figured it must be too high, and ran the experiment again until they got a more-erroneous value, one that was nonetheless higher. Eventually it worked itself out.

But climate modeling isn't measuring something objective and static like the charge of the electron. It's prediction. I'm afraid that the incentives are to credit models that predict more warming just a bit more than those which predict less; the expected effect would be that the predicted warming effect would get larger over time.

Please note that I'm not calling climate science a "Cargo Cult", as Feynman put it; I accept the basic premise of anthropogenic warming on first principles, and see that historic measurements (not to speak of recent ones) show a warming trend. There is cause to be concerned.

Nonetheless, it would be surprising if climate modeling, which is inherently inexact and involves irreducible guesswork, didn't drift toward the more alarming, due to similar social forces to those identified in Feynman's essay.

Re: Climate models are running red hot, and scientists don’t know why

#130

Post by New_Horizon » Mon, Feb 03, 2020, 4:12 PM UTC

cm2187 wrote: post #118

justadudeama wrote: post #23

I am not a climate change denier by a long shot, but stories like these give a ding to the credibility of climate scientists. > "So we can't throw them out yet." This might be an elementary view of science, but I think there is a danger here that while everyone is making their models, if anyone is an outlier they go and tweak their model to match the patterns of others: 'Klaus Wyser’s group "switched off" some of the…

That's the main problem I have with climate science. They don't really have the luxury of proving by experimentation, and I have seen enough perfectly good backtestings in my industry (finance) that go wildely off as soon as they go live, that I have a fundamental mistrust of backtesting as a way to calibrate a predictive model.

Especially because they seem to test it by making it predict history, but we don't have anywhere near the same amount of historical data. So what are you testing, really? Just that it accurately finds average temps?