
Earth to warm more quickly, new climate models show (By 2100, could rise 6.5C) - consumer451
https://phys.org/news/2019-09-earth-quickly-climate.html
======
rekabis
And the really scary thing is that anything above +8℃ has a very real chance
of flipping the planet into a Venus Scenario. Recent work has shown that the
Earth sits at the very inner edge of the solar system’s habitable zone. As the
sun has aged across billions of years and burned through its fuel, it has
heated up and moved the zone outward. As such, the planet could have had
higher greenhouse gas levels in the past with life still surviving, but it
cannot have such levels now without life dying and the planet becoming a
second Venus. At +8℃, equatorial cloud cover becomes impossible to generate,
and the amount of oceanic heating accelerates. Methyl Hydrates begin boiling
off everywhere, and it becomes too hot to live between the 60th parallels -
humanity (or what’s left of it) must pack itself around the poles to survive.
At some point, the amount of greenhouse gas creation exceeds the ability of
life to counteract said gases, and things heat up until all life on the planet
dies.

~~~
spodek
The scariest thing to me is that people think their actions won't make a
difference.

I was speaking to an organization about reducing its flying. In the spring
they wouldn't consider it. One 16-year-old girl, Greta Thunberg, sailing
across the Atlantic put the initiative on the table.

She didn't plan to influence that organization but she did.

We all have that potential.

I've given one TEDx talk on environmental leadership
[http://joshuaspodek.com/my-tedx-talk-is-online-find-your-
del...](http://joshuaspodek.com/my-tedx-talk-is-online-find-your-delicious)
with a second in a few weeks
[https://www.tedxwaltham.com/tedxwaltham-2019](https://www.tedxwaltham.com/tedxwaltham-2019).
My podcast [http://joshuaspodek.com/podcast](http://joshuaspodek.com/podcast)
is creating role models among globally renowned people.

I've become somewhat of a role model -- in my fourth year of not flying, I
haven't filled a load of trash in over a year, I pick up litter every day --
and people write me to tell me they're doing it, as are their friends.

These results aren't enough, and some disasters will happen, but each person's
actions contribute, including yours -- mostly by leading others to contribute
too.

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narratives
Curious if anyone here has evaluated any of these models? I’ve done a cursory
search and haven’t found a source to play with. I’m curious to know what
variables were included, what variables were excluded, how the future is being
predicted, and to what degree the creators any of these models have been
accurate in predicting the future previously.

Does anyone have a good explanation as to why it’s prudent to attempt to
predict anything about anything 80 years in the future?

Also curious if there is evidence of predicting the future in any field. If
so, I’m wondering what the accuracy rate is one month out, one year out, five
years out, etc.

I’ve done some modeling with sales data, trying to predict demand in a given
market based on a series of variables. The issue is how much weight to put on
each variable. With lots of market research and historical data, we were able
to get decent estimates a couple of months in the future. Beyond that? It was
complete speculation. Especially if we missed an important variable, which is
common, since its impossible to know what variables will (and won’t) be
relevant in the future.

I imagine climate modeling is more complex than my sales models, meaning more
variables that were included, more variables that were excluded (especially
the ones that are unknown unknowns), and a much larger margin for error
(especially as time increases).

I raise this as I haven’t seen any push back from the HN community on articles
like this. Not sure if I’m missing something, if it’s political bias, or a
fear of ostracized for questioning these reports. Either way, I’d be
fascinated to see some deeper analysis on the topic from the minds on this
forum.

Have humans ever created a complex model that has enabled us to predict the
future with any degree of accuracy? If so, how far into the future and with
what degree of accuracy? If not, what is the purpose of a model extrapolated
out to 2100?

Trying to imagine when technology will reach X milestone (AGI, for example)
reminds me that it’s probably wise to be less sure of our predictions. The
last US presidential election reminded me of this too.

~~~
makerofspoons
The DOE Energy Exascale Earth System Model is on GitHub:
[https://github.com/E3SM-Project/E3SM](https://github.com/E3SM-Project/E3SM)

Here is some analysis of how the predictions made by some climate models have
done: [https://www.carbonbrief.org/analysis-how-well-have-
climate-m...](https://www.carbonbrief.org/analysis-how-well-have-climate-
models-projected-global-warming)

They have done a remarkable job since the 1970s.

~~~
slowhand09
Unpopular opinion warning: Not an expert here but I worked on NASA's "Mission
to Planet Earth" program for a few years. Cherry-picking of models that
produce results that meet the current agenda is not uncommon. Just as
researchers have a (deserved IMHO) reputation for publishing data that concurs
with their topics...

~~~
slowhand09
[https://journals.plos.org/plosone/article?id=10.1371/journal...](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0200303)
[...]" found 64% of surveyed researchers reported they had at least once
failed to report results because they were not statistically significant
(cherry picking); 42% had collected more data after inspecting whether results
were statistically significant (a form of p hacking) and 51% had reported an
unexpected finding as though it had been hypothesised from the start
(HARKing)."

[https://www.env-econ.net/2017/07/cherry-picking-
results.html](https://www.env-econ.net/2017/07/cherry-picking-results.html)

[https://ori.hhs.gov/videos/case-study-
list/3037](https://ori.hhs.gov/videos/case-study-list/3037)

[https://www.pnas.org/content/pnas/early/2018/03/08/171075511...](https://www.pnas.org/content/pnas/early/2018/03/08/1710755115.full.pdf)

------
makerofspoons
In a world with such high climate sensitivity, is there still a realistic
pathway to an acceptable outcome? SSP1 2.6 was already highly optimistic and
with these two new models even it doesn't keep us below 2 degrees.

~~~
trevyn
Perhaps it’s time to start considering how to choose to live given
unacceptable outcomes.

~~~
consumer451
> Perhaps it’s time to start considering how to choose to live given
> unacceptable outcomes.

Maybe I am misunderstanding your statement, but to which period of time are
you referring to? Your lifetime? 3 generations?

The long now includes a non-zero probability of a collapse of atmospheric
oxygen, and complete human extinction within ~3600 years. [0]

[0]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5138252/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5138252/)

~~~
AbrahamParangi
I may be misunderstanding it but that paper reads as completely ridiculous.

We haven’t had a hypoxic atmosphere in the history of the earth since the
evolution of photosynthesis (that’s a 2 Billion Year track record). The
support for the plausibility of the author's hypothesis is that if you fit a
_parabola_ to the data over a certain time window, you get 100% decrease in
atmospheric oxygen in a few thousand years??

That model is just nuts. By the same token it predicts we will have negative
oxygen shortly thereafter.

~~~
consumer451
I would love to have someone convince me that this paper is utter rubbish, so
I really appreciate your comment. I am also likely a bit annoying as I don't
have a science background.

However, you said:

> We haven’t had a hypoxic atmosphere in the history of the earth since the
> evolution of photosynthesis (that’s a 2 Billion Year track record).

This research seems to disagree, doesn't it? [0]

> Climate change triggered by volcanic greenhouse gases is hypothesized to
> have caused the largest mass extinction in Earth’s history at the end of the
> Permian Period (~252 million years ago). Geochemical evidence provides
> strong support for rapid global warming and accompanying ocean oxygen (O2)
> loss, but a quantitative link among climate, species’ traits, and extinction
> is lacking. To test whether warming and O2 loss can mechanistically account
> for the marine mass extinction, we combined climate model simulations with
> an established ecophysiological framework to predict the biogeographic
> patterns and severity of extinction. Those predictions were confirmed by a
> spatially explicit analysis of the marine fossil record.

[0]
[https://science.sciencemag.org/content/362/6419/eaat1327](https://science.sciencemag.org/content/362/6419/eaat1327)

~~~
gus_massa
In the first article, fitting that data with a parabola+trigonometric is a
very big red flag. The error interval for the quadratic coefficient must be
huge, but I can't find it.

It may be fit with a line+trigonometric to get some approximation for the next
few years (10? 100?). With a line you get 50000 years to the 0 oxygen level,
that is less alarmist than 3600 years.

Also, without a good model it's a bad idea to extend these projections too
much. There are a lot of natural process that depend on the concentration of
oxygen and will change. For example, under 15%-10% concentration of oxygen you
can't burn wood so you solve the problem of forest fires
[https://en.wikipedia.org/wiki/Limiting_oxygen_concentration](https://en.wikipedia.org/wiki/Limiting_oxygen_concentration)

------
Scarblac
Maybe only Peak Oil can save us. How much carbon is there? Surely we _can 't_
continue unabated indefinitely?

~~~
Ancalagon
With new tech like Fracking, there's a lot of un-tapped resources still
unfortunately :/

~~~
consumer451
Indeed. My intuition here is that climate change is an investment problem at
this point. The technological solutions already exist.

How do we convince all investors to walk away from a nearly guaranteed and
superb return?

This is the main problem which we currently face in my view.

~~~
rmilejczz
By hampering the viability of non renewables via a steep carbon tax, read more
here:

www.forbes.com/sites/howardgleckman/2018/10/10/bill-nordhaus-the-nobel-prize-
climate-change-and-carbon-taxes/

The real barrier is making something like this policy imo

~~~
Scarblac
Or just making them illegal outright.

But the whole world has to participate...

------
slowhand09
A Pinatubo, Laki, or Krakatau event can easily move the ground truth of
climate change.

