
Climate Science Is Not Settled - T-A
http://online.wsj.com/articles/climate-science-is-not-settled-1411143565
======
scarmig
"The crucial scientific question for policy isn't whether the climate is
changing. That is a settled matter: The climate has always changed and always
will. Geological and historical records show the occurrence of major climate
shifts, sometimes over only a few decades. We know, for instance, that during
the 20th century the Earth's global average surface temperature rose 1.4
degrees Fahrenheit.

Nor is the crucial question whether humans are influencing the climate. That
is no hoax: There is little doubt in the scientific community that continually
growing amounts of greenhouse gases in the atmosphere, due largely to carbon-
dioxide emissions from the conventional use of fossil fuels, are influencing
the climate. There is also little doubt that the carbon dioxide will persist
in the atmosphere for several centuries. The impact today of human activity
appears to be comparable to the intrinsic, natural variability of the climate
system itself...

Society's choices in the years ahead will necessarily be based on uncertain
knowledge of future climates. That uncertainty need not be an excuse for
inaction."

Much better than I expected of the WSJ. If it consistently took this line
instead of buying into absurd conspiracy theories or claiming snow in January
means climate change is a hoax, our national discourse would be much
healthier, on both sides.

------
tjradcliffe
Steve Koonin is an incredibly smart guy with a huge amount of experience in
climate and energy issues, and is saying things in this article that any
competent computational physicist who has looked into climate modelling
believes.

Compare for example my own short take on the same issues, written two years
ago: [http://www.tjradcliffe.com/?p=886](http://www.tjradcliffe.com/?p=886)

You'll see basically similar concerns raised. If you're seriously wedded to
the idea that consensus is important to the science, you should dig up the
independent opinions of a few other computational physicists (not climate
scientists, who are not computational physicists). Having done so, you might
find that there is a consensus amongst computational physicists that climate
models are problematic in ways that make them questionable guides to policy,
although most of us will also say that we should be concerned about the amount
of garbage we are dumping into the atmosphere (and there are reasons to want
to get off fossil fuels that go beyond the climate change argument.)

Denialists have poisoned the public discourse on climate change, but Warmists
have unfortunately responded by digging in their heels in a particularly anti-
scientific way. I hope Koonin's piece will help bring the scientific
discussion back to fundamentals, and perhaps decouple the policy discussion
from models a bit.

For example: we know that carbon taxes work pretty well in reducing CO2
emissions ([http://www.theglobeandmail.com/globe-debate/the-insidious-
tr...](http://www.theglobeandmail.com/globe-debate/the-insidious-truth-about-
bcs-carbon-tax-it-works/article19512237/)) and we know that carbon taxes can
be used to reduce corporate and income taxes. So anyone who is opposed to
carbon taxes is necessarily in favour of higher corporate and income taxes.

This is a policy discussion that can and should be had independently of any
detailed climate model results, and I invite everyone who is in favour of
higher corporate and income taxes to chime in here in support of their
position, and explain why those taxes are so much better than the carbon taxes
that could partially replace them.

~~~
quink
[http://www.skepticalscience.com/climate-models-
intermediate....](http://www.skepticalscience.com/climate-models-
intermediate.htm)

[http://www.theguardian.com/environment/climate-
consensus-97-...](http://www.theguardian.com/environment/climate-
consensus-97-per-cent/2014/jul/21/realistic-climate-models-accurately-
predicted-global-warming)

And can you please stop with the 'Warmist' label? It's stupid, about as much
as 'denialist' is narrow for the veritable zoo of opinions - educated or
uneducated - that's sprung up in the public discourse.

I've also read your post and 1-2 W/m2 does sound like very little. However,
and I quote from Wikipedia:

> Of the ~340 W/m2 of solar radiation received by the Earth, an average of ~77
> W/m2 is reflected back to space by clouds and the atmosphere, and ~23 W/m2
> is reflected by the surface albedo, leaving about 240 W/m2 of solar energy
> input to the Earth's energy budget.

That's a change of 0.5%. Doesn't sound like much, does it, but at 273 K that
corresponds to about 1.5 degrees already. At the upper end of that and 300 K
it's 2.5 degrees. Sure, it's simplistic and it's how to keep it quite that
straightforward, but to see that number and be ignorant enough of the context
to trivialise it and call it not a big deal is pretty disingenuous. Sure, a
2.5 K (or something like it) rise isn't going to bring the downfall of
civilisation per se. But there's more to it than that. And, mind you, 2.5 K is
at the lower end of IPCC projections, so there's evidently a lot more ground
to cover than the simplistic numbers mentioned here.

~~~
tjradcliffe
Who is trivializing anything? This is what is so bizarre about these
discussions, and why I use the term "Warmist": because it identifies a nearly
religious zeal on the part of some non-scientists who insist that anyone who
does anything other than repeat the mantra "the science is settled; we must
implement every imaginable solution except nuclear power" is somehow
"trivializing" the issue.

I'm clearly on the record as being concerned about climate change and strongly
in favour of implementing social policies (including carbon taxes) that will
a) reduce GHG emissions and b) protect the most vulnerable, but because I
don't quack like precisely the right kind of duck I'm routinely accused of
somehow trivializing something, or being the enemy (this is not the first time
I've had this kind of discussion, obviously). This is what you see from rival
religions, not from scientists. I was involved in the 17 keV neutrino
controversy, so I'm no stranger to scientific disagreement, and it simply
doesn't have this strange dynamic.

If anyone is trivializing anything, it is Warmists trivializing physics. For
example, why anyone would go from a 0.5% change in energy budget to a 0.5%
change in absolute temperature is beyond me. Heating and temperature in the
atmosphere are connected by complex and non-linear factors, which is one of
the reasons we need to do modelling in the first place. Even in the simplest
case of a black body the non-linear Stephan-Bolzmann law applies, not Newton's
law of cooling (which is linear, but irrelevant to this case.)

So the argument you're making is not even wrong: it simply doesn't speak to
the question of what the plausible effect of climate change on the Earth in
general and humanity in particular will be.

This kind of argument just feeds the Denialist trolls who are doing so much
damage to this discourse, because they will pick up on your errors and cry
"hoax!" and other such nonsense rather than "honest, innocent and naive
mistake", which in fairness what I think your error most likely is.

Finally, as I said above, I've had this kind of discussion before and it's
never ended well, so I'm going to stop here and let you have the last word.
Enjoy!

~~~
cema
I agree that global warming attracts religious types. As a result, it is
generally hard to have a serious conversation about it. HN has a better ratio
of science vs religion, luckily.

~~~
benjohnson
I'd deeply religious - and I concur.

Based on my experience, the debate about Global Warming is is mostly
polemical.

In my opinion, a debate about measurable natural phenomena should be
scientific - where a single verifiable fact trumps all previous consensus and
conjecture.

------
lutorm
I always thought that when people used the word "settled" in connection to
climate change they were referring to the question of whether humans have
influenced climate. Even though this article dismisses that question as "yeah
there's little doubt about that", this is _precisely_ what plenty of people
have been arguing is not the case. So this article seems a lot like moving the
goal posts to me.

Obviously climate science as a whole isn't "settled", any more than any other
science is "settled".

~~~
hencq
Yeah I agree. The article was actually good and calls out very reasonable
criticisms against current climate science. However the headline makes it seem
the debate on whether humans influence the climate isn't settled.

~~~
ende
One thing that the author points out is that the impact by humans is
relatively small (compared to natural sourcing), and that natural variation is
both vast and frequent.

------
j2kun
"Settled" is not a word you can use when describing any science. Medicine is
not settled, nor is physics or computer science. But we can still glean useful
insights from the evidence and experiments we have done. While it's wrong to
claim climate science is settled, I can't recall any credible figure who said
that it was. So to me this seems like a bit of a straw man.

------
haberman
"Climate Science Is Not Settled" is an irresponsible title IMO when the main
points of contention in public discourse are whether anthropogenic climate
change is even real or not, and action vs. inaction.

It's a good article and I'm happy to see it (assuming the information is
accurate). But deniers will point to the title to argue that the whole things
is a hoax and that we should do nothing.

I'm sure the phenomenon of "Warmists" is a real thing too, and something to
watch out for. But it's incredibly hard to talk about the subtle points
presented in this article when so many people refuse to believe that anything
is happening at all. It's like trying to debate foreign policy with someone
who thinks that 9/11 was an inside job.

------
tlb
I'm surprised by the finest possible resolution quoted, a 60 mile grid. It
corresponds to about 55,000 cells covering earth (times maybe 100 altitude
bands). That's not a large amount of memory.

I assume the limitation is that all those cells have to be simulated in small
time slices for 100 years, and the necessary time slice would scale inversely
with the grid size, so computation is O(n^3) on the inverse size of the grid.

Can someone comment on what kind of computer it would take to halve the size
of the grid?

~~~
tjradcliffe
There are usually quite a bit fewer than 100 altitude slices. There may be as
few as 10: [http://www.ipcc-
data.org/guidelines/pages/gcm_guide.html](http://www.ipcc-
data.org/guidelines/pages/gcm_guide.html)

Simulations are typically done in one day time-steps or less.

The thing is, there is a lot of physics going on in each cell, and in some
respects reducing the cell size makes things more problematic rather than
less. For example, the effects of a supercell thunderstorm can dominate the
atmosphere over tens of kilometers. With a 100 km (60 mile) scale you can
plausibly average over those effects within a cell, as you can reasonably
claim that most such "local" phenomena will be happening well away from cell
boundaries.

So as you reduce the cell size, you start having to think about the internal
details of local disturbances that you were previously averaging away and
hoping to catch in your overall parameterizations, and the model complexity
goes up tremendously, likely without becoming a whole lot more accurate.

Even at these large scales the amount of physics that goes on within a single
cell is huge, and getting all the heat and mass balances right is
fantastically difficult, which is where a lot of the computational power goes.

So it isn't really a question of halving the grid size while keeping the
physics the same, because you are going to have to substantially revise your
model to accommodate the new scale. I'm sure this work is ongoing, but it's
extremely complex and difficult.

~~~
rwallace
What sort of physics calculations can you do within a cell? I would have
expected the data structure for a cell to contain a handful of scalar
parameters (e.g. temperature, pressure, humidity, velocity vector) related by
a few scalar equations - a negligible amount of computation. It sounds like
there's quite a few orders of magnitude more stuff going on within a cell than
I would have expected. What am I missing?

------
grifpete
It seems that the article has a simple thesis. a) climate is hard b) human
activity is affecting it but because it's hard it's tough to know how much c)
hence it's difficult to know what the correct policies should be.

As an economist might say - without clarity on the positive, it's challenging
to resolve the normative.

But I am a little puzzled by the failure to discuss outcomes in terms of
mathematical expectation. And of course, the author knows more than I ever
will about this.

Hence: If our activity might just trigger a sequence of events leading to
human extinction...(in other words such a sequence is conceivable and
credible) then even if the risk is low as estimated by our (weak) ability to
assess such risk, then the outcome is surely so hideous that if our policies
are taking us in a direction that makes such an outcome more likely (even if
we are not sure by how much) then there is cause for caution and re-
examination of policy. It seems to me that our situation at present is of this
form. Despite our poor understanding and the fact that things aren't 'settled'
(as if they ever will be) this unsettled 'knowledge' is all we have and we
have to take it seriously, most particularly if the possible outcomes are
ghastly. We can't just wait for better science.

------
Daishiman
Wow.

I am amazed that an article filled with such a vast amount of FUD is
frontpaging. But let's go point-by-point, lest the science described in
thousands of papers of climate research get lost in the cloud of false
skepticism, shall we?

> The models roughly describe the shrinking extent of Arctic sea ice observed
> over the past two decades, but they fail to describe the comparable growth
> of Antarctic sea ice, which is now at a record high.

The science of _why_ Antarctic sea ice extent is growing is perfectly well
known: the discharge of melting cold water from the Antarctic glaciers forms
ice as it hits the coastal winds of the continent. That the models don't
necessarily account the extent of this is almost irrelevant, since the sea ice
extent has a very minute impact on climate patterns.

Let us note that this is a not-at-all subtle piece of FUD that would appear to
account that Antarctic sea ice is compensating for Arctic melting. It's not.
There's over 500 Gt of yearly glacier loss in the Antarctic, and the sea ice
extent which is, at most, a few meters thick, is absolutely minuscule in
comparison to the amount of additional water dissolving into the sea from
kilometers-thick walls of ice. Also, the topic has been reasonably well-
studied, and the changes in the atmosphere are more than enough to account for
the observed effects.

> Even though the human influence on climate was much smaller in the past, the
> models do not account for the fact that the rate of global sea-level rise 70
> years ago was as large as what we observe today—about one foot per century.

It is most definitely increasing, and it is accelerating rapidly, especially
if the West Antarctic Ice Sheet accelerates its collapse
([http://www.skepticalscience.com/sea-level-
rise.htm](http://www.skepticalscience.com/sea-level-rise.htm)). The fact that
we have been observing linear trends thus far doesn't mean that we'll continue
to observe them; evidence points that we're in the beggining of an exponential
loss of ice.

> A crucial measure of our knowledge of feedbacks is climate sensitivity—that
> is, the warming induced by a hypothetical doubling of carbon-dioxide
> concentration. Today's best estimate of the sensitivity (between 2.7 degrees
> Fahrenheit and 8.1 degrees Fahrenheit) is no different, and no more certain,
> than it was 30 years ago. And this is despite an heroic research effort
> costing billions of dollars.

This is, again, FUD.

First of all, the radiative forcing produced by CO2 is well-known and
established by physics. It is known that the Earth's albedo is decreasing, and
the certainty that out lower bounds are erroneous has increased substantially.

Moreover, we are now aware of potential feedback loops that we didn't know
about. It's interesting that he's never mentioning the Big One: the potential
for frozen clathrates in Siberia and the Arctic to release methane that would
trigger a certain mass extinction event.

> A transparent rigor would also be a welcome development, especially given
> the momentous political and policy decisions at stake. That could be
> supported by regular, independent, "red team" reviews to stress-test and
> challenge the projections by focusing on their deficiencies and
> uncertainties; that would certainly be the best practice of the scientific
> method. But because the natural climate changes over decades, it will take
> many years to get the data needed to confidently isolate and quantify the
> effects of human influences.

So, in his opinion, the models clearly described in papers, the data publicly
available by NASA and dozens of different government organizations is not
enough? A 3000-page report summarizing the findings of hundreds of papers,
with multiple, independently corroborated lines of evidence using different
data sets isn't enough?

This an _obvious_ attempt to discredit climate scientists. I would suggest
anyone who has a shred of doubt as to the integrity of these people that you
just walk into any Atmospheric Sciences Department of your local university
and buy any teacher a cup of coffee and have a chat. Seriously, they will talk
your ear off about their research.

As a personal note, most climate scientists are the kind of people smart
enough and capable enough to be making decent cunks of money outside of their
chosen field (a combination of knowledge in physics, chemistry, and
computational modeling are desired skill in many lucrative fields). They're
not doing this for the money, or the recognition, and it pains me that people
are willing to believe the ramblings posted in a Murdoch-owned newspaper on
the matter without willing to question the economic interests behind climate
denialism. But I digress.

> But climate strategies beyond such "no regrets" efforts carry costs, risks
> and questions of effectiveness, so nonscientific factors inevitably enter
> the decision. These include our tolerance for risk and the priorities that
> we assign to economic development, poverty reduction, environmental quality,
> and intergenerational and geographical equity.

There's something that should be really important, which people raised on the
typical media diet of "two sides of the story" and "fair and balanced" should
understand:

We're not debating whether climate change is something serious or not.

The current debate is whether we're facing a future where "merely" the
following things will happen:

* An acidified ocean where almost all fish stocks will collapse, with a PH that will make the growth of crustaceans and zooplankton difficult, to say the least.

* Megadroughts will become a common occurency, as will increased levels of flooding resulting in losses of crop efficiencies above 10%

* All of the planet's ecosystems will be permanently affected, making the harvesting of crops such as coffee and cocoa a thing of the past

* An acceleration into our current period of mass extinction, with unforeseen consequences

Or, nn the other extreme, quite literally, we have a scenario of a degradation
of the Earth's biosphere to the point where humans face complete extinction
within the next century.

The last scenario could be triggered by one of the many feedback cycles which
include the sudden release of methane clathrates, an exponential collapse of
the West Antarctic Ice Sheet leading to the rapid increase in sea level of
multiple feet, or just sufficiently large megadrought events in enough places
in the globe to disrupt the global food supply chain. Hell, just an increase
in temperature of 4 degrees C ("just") would be enough.

My final rebuttal:

> Individuals and countries can legitimately disagree about these matters

No, they cannot, unless they're legitimate experts in climate science with an
understanding that actually improves upon what we have, they have squat to say
on the science of it.

This fake notion that anyone can have an opinion on knowledge that's in flux
is intellectually dishonest. Experts are allowed to disagree. Us laymen have
almost nothing to add to the conversation, unless we want to gamble with our
own demise. Anyone who thinks otherwise is plainly ignorant of the science,
and that's not a point in discussion.

The only thing this discourse does is play down the supposed "alarmism" of the
situation. I don't know man, if you think that a potential, non-trivial chance
of the collapse of the biosphere isn't something to be alarmed of, then I
don't know what is.

~~~
cema
_False skepticism_ is a new concept for me.

Still, I would like to thank you for a detailed answer. For me, an outsider to
the science and politics of climate affairs, it sheds light on one party of
the argument. Perhaps the other party will have an equally eloquent exposition
- I have not yet read all the comments in this thread.

~~~
Daishiman
I don't know whether it was sarcastic or not, but to clarify: false skepticism
is when FUD is cast around on the excuse that it is an attack on an
institutional status quo. The reason why it is false is because real
skepticism has a knack for rigorously questioning specific points in lines of
evidence and proposing why established theories are cargo-culting their data.

As you can see here, none of that is taking place. In fact, the entire article
is a massive logical fallacy that implicitly tries to frame the IPCC's current
policy proposals as some sort of extreme.

If anything, the IPCC's report is _extremely_ conservative, as it does not
analyze the Black Swan events which include methan clathrates and the loss of
effectiveness of carbon sinks, or the warming of the deep oceans.

Thus, it frames the debate in a fallacious way.

Actual skepticism has been well-served by the internal debates amongst climate
scientists, and if you read the stuff by the emintent experts, you will see
that they are _shitting their pants in fear_.

When climate experts are seriously scared of the possibilities of total
extinction, we should be listening, and at best, making thoughtful critiques.

This,in contrast, is stinking bullshit.

~~~
cema
Look, I appreciate your point, but _shitting pants_ is not an argument. Not a
scientific argument.

------
e40
I was hoping to find something about acidification of sea water, caused by
CO2. Even if the warmth of the earth isn't caused by us, it seems like the
acidification of the ocean might be. A similarly skeptical look at this would
be welcomed.

~~~
ende
Please, this debate is contentious enough without bringing SQL-vs-NoSQL into
it.

------
hristov
FUD is not only for operating systems anymore.

------
qthrul
Science is that which explains and predicts.

If you are missing either of these attributes -- you are in the realm of
legends, folklore, and farmer's almanacs.

------
quink
> Dr. Koonin was undersecretary for science in the Energy Department during
> President Barack Obama's first term and is currently director of the Center
> for Urban Science and Progress at New York University. His previous
> positions include professor of theoretical physics and provost at Caltech,
> as well as chief scientist of BP, BP.LN +0.42% where his work focused on
> renewable and low-carbon energy technologies.

> We are very far from the knowledge needed to make good climate policy

Complete and total horseshit. Even if you'd only assume that the scientists
are 90% right any good actuaries will tell you that you should spend about 90%
on measures that back up what they've put forward.

Hacker News, I expected something better than this in the #2 spot.

Here, read this:
[http://www.ipcc.ch/report/ar5/](http://www.ipcc.ch/report/ar5/)

Or this:
[http://en.wikipedia.org/wiki/Global_warming](http://en.wikipedia.org/wiki/Global_warming)

Or this:
[http://en.wikipedia.org/wiki/Ocean_acidification](http://en.wikipedia.org/wiki/Ocean_acidification)

Or this one is excellent:
[http://www.skepticalscience.com/](http://www.skepticalscience.com/)

Edit: Alright, here we go with the downvotes for calling out bullshit
regarding climate change on Hacker News. Well, it's not like I expected any
better. Next I expect a replies either trying to argue random points about how
there were forests in Greenland in the middle ages or some pretensions about
being open-minded. While still barely having a grasp of a periphery of
relevant facts.

But that's OK, the warriors having upvoted this to the top immediately know
best. Or at least as well as Murdoch, publisher of the WSJ who has recently
installed a prime minister in Australia who called climate change 'crap' and
has abolished a carbon tax a minute fraction of those found in the rest of the
OECD.

~~~
triangleman
What's your point? That Dr. Koonin is not a trustworthy source because he
worked for BP?

~~~
lotsofmangos
I would take the opinions of an industry expert with a large pinch of salt on
the subject of negative externalities of the industry they are involved in, no
matter what the industry.

