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Comment by paulddraper | Hacker News Reader

Also, the actual questions are not just "Has Earth's average surface temperature increased 0.8 degree Celsius since 1880?" but:

* What is humanity's effect on global warming?

* What meteorological and ecological effects does global warming have?

* What is the magnitude of impact of hypothetical changes to human behavior?

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1. Lots 2. Very 3. Extensive

I know this is flippant, but the answers are all generally pretty well-known

The poster should not ask such silly questions, just trust the science!

This answer is more flippant than you can imagine.

#3 Is the worst - if we have learnt anything in the past century, it is that our attempts at behavioural changes rarely work[i], and even when they do they often result in the opposite effect[ii].

[i] - My favourite book that points this out is Behavioural Adaptation and Road Safety. Well worth a read. Examples are many, such as in the case of criminalising texting while driving, which results in "crotching" (texting from a phone on your lap) and has resulted in increased accidents.

[ii] - Plenty of examples of this already on the environmental scene:

    - let's use plastic bags to save trees! oh no plastic bags are worse!

    - let's use diesel rather than petrol! Here, have subsidies! Oh no, it's making everything worse

    - let's improve energy efficiency! oh no, now more energy is used! https://en.wikipedia.org/wiki/Jevons_paradox

Within orders of magnitude perhaps.

In 2008, computer models from Naval Postgraduate School, NASA, Institute of Oceanology, and Polish Academy of Science predicted ice-free Artic summers by 2013. [1] The study was prominently cited in Al Gore's acceptance of the Noble Prize, which was awarded for his dedicated advocacy of climate change science.

In 2013, the US Dept of Energy and US Navy predicted it would be gone before 2019. [2].

For more ice-free Artic science, see https://en.wikipedia.org/wiki/Arctic_sea_ice_decline#Ice-fre...

Complicated systems are complicated. Science knows as much about climate change as it does about cholesterol.

[1] http://news.bbc.co.uk/2/hi/7139797.stm

[2] https://www.theguardian.com/environment/earth-insight/2013/d...

You've taken a quote from a study that talked about the lower bound of the range of estimates (earliest possible ice free date) and specifically mentioned the high range of uncertainty (even in the news story pull quote), and you've decided that was a firm prediction which has been invalidated. This is your bad science at best, your deceitfulness at worst.

"We predict X will happen sometime between 10 and 50 years from now, sorry about the high range of uncertainty"

"Welp, it has been ten years and one day and X didn't happen, THOSE SCIENTISTS WERE ALL LIARS, DON'T BELIEVE THE SCIENCE"

Just dishonest.

The first instance was a requote from Al Gore's Nobel Prize speech. I'm not sure what the bounds were in the source material; it is possible that Gore (dishonestly?) cited only the lower bound. What was the upper bound?

The second instance used the upper bound (2016 ± 3 years).

I never said "THOSE SCIENTISTS WERE ALL LIARS, DON'T BELIEVE THE SCIENCE"; I said those scientists cannot yet predict accurately years ahead the effects in such a complex system.

Are they? Then provide a source eberyone in the thread is asking for. I think this is the issue. Both sides declared themselves so correct that they see no need to 'show their work'. Clearly there is a progressive warming, there is a strong correlation with co2, the greenhouse model seems mostly confirmed, but what else? I am not contesting your assertion, but seeking understanding. Being flippnt is how we got in this mess.

If you accept that humans pump a lot of CO2 into the atmosphere, I'm not sure why you're asking for a specific citation; if you're looking for papers that answer the spefific question of whether humans are contributing to global warming, and the consensus among scientists in all disciplines concerned, there are several:

https://science.sciencemag.org/content/306/5702/1686.summary

https://science.sciencemag.org/content/292/5515/270

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.800...

Exactly - and I would add another 2:

* What are the confidence intervals around the answers to the above? I.e., what are the probabilities of the ranges of answers to the above.

* Assuming that such probabilistic models have been running, unchanged, for at least a decade - how have these probabilities held up, where it is possible to measure the actual outcomes?

One extremely humorous IPCC report mentioned that cloud cover changes are poorly understood, could massively increase or decrease warming feedbacks likely drowning out all other signals, but for the sake of the report would be ignored.

So much science-y science you just can't stand it.

We won't like the results of the updates on accuracy that have been made, say the rumors. Still some time off until publication though, who knows what'll happen until then.

edit: One morbidly humorous plot is this one:

https://www.ipcc.ch/site/assets/uploads/sites/2/2019/02/SPM3...

P1, P2 and P3 are just.. kind of ridiculous with that emission drop. It's the kind of thing where you go 'haha sure' and then drown your thoughts in beer.

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