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Comment by kstenerud | Hacker News Reader

"Let us look at the predictions made in 1990: they predicted an increase in temperature of 0.3C per decade, plus minus 0.1C. Yet less than 0.2C of warming per decade was observed. To be blunt, they got it flat wrong."

How much less than 0.2C was it? 0.3 +/- 0.1 means it can be anywhere from 0.2 to 0.4, so unless it was grossly under 0.2, it wasn't flat wrong.

"there are alternatives to banning oil production: solar radiation management. We might be able to setup space mirrors or otherwise increasing the reflectivity of our atmosphere." ... "But keep in mind that we will soon run out of cheap oil in any case."

In other words, "Fear not, for we might just come up with some miracle technology or something. It might just all work out in the end so just stay the course and don't worry!"

If you're going to call out others for poorly reasoned arguments, at least have well reasoned arguments of your own.

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I think the bigger thing to pull from that quote centers on the word "prediction". The IPCC FAR didn't really make any predictions. Instead, it made a series of projections (twelve of them, to be precise) based on running various sets of hypothetical parameters through a climate model.

Some of those projections were based on very pessimistic scenarios (very high CO2 sensitivity, very high future CO2 emissions). They projected very high increase in temperature. Other projections were based on more optimistic scenarios. They projected a lower increase in temperature.

Now, the number that the author quotes (0.3C +/- 0.1C per decade) corresponds to the range for the block of projections that assumes a very high climate sensitivity - a sensitivity that turns out to be high. Since the projection was based on a scenario that did not correspond to reality, if we assume that the models were reasonably accurate then it should not surprise us that the projection didn't end up corresponding to reality, either. So there's an interesting omission. . . and an example of how what someone doesn't say can say as much about their position as what they do say.

Another omission that speaks volumes is highlighted if you compare the projections for scenarios that ended up being more representative of how those parameters did evolve over the next two decades to what global temperatures have been doing over that time period. Far from the alarmist claims of gloom and doom that the author would like to suggest were made, the projection for the scenario that ended up most closely corresponding to what actually happened slightly underestimated the actual change in temperature. But by an amount that was quite small in comparison to the error bars, so an honest and scientific analysis of the TAR projections would force us to conclude that in this particular respect the IPCC's analysis was actually dead on.

Poorly reasoned arguments are certainly unfortunate. . . but if you really want to make your position look bad, try blatantly cherry-picking the data.

Well, he used the same numbers that the IPCC FAR report's "Policymaker's Summary" section chose to use, which repeatedly uses the term "is predicted" (admittedly, qualified with "based on current model results" or specific scenarios.) The explicit purpose of that section was to suggest possible policy options based on a set of long-term events stated to be found _with certainty_ (their words) by the working group that were going to occur.

Let's say that I am a "policymaker" and not a climate scientist, and I sensibly choose to defer to experts how I should plan for any potential climate change. That's the section that was written specifically to me for that purpose, by the working group--with the same numbers that this guy quotes.

Those cases where the BaU figures are used are disclaimed with the qualifier, "Under the Business-as-Usual scenario", and the ensuing discussion is pretty clearly intended as an exposition on how we should not have wanted to mimic the BaU scenario because, as the model projections for that scenario indicate, there was compelling reason to believe that the consequences would have been bad.

Again, cherry-picking things out of context does not a compelling argument make. Unless the people you're trying to compel can be trusted to not check your sources too carefully.

And of course the corollary to that is, if the topic is controversial you should always thoroughly fact-check your sources.

(Speaking of, I couldn't find the phrase "with certainty" in either of the three FAR policymakers summaries. . . perhaps you meant "with confidence"? Regardless, it's skirting the edge of dishonesty to use the phrase "their words" to describe something that isn't their words.)

Among the many annoying half-truths of this article is that he doesn't make any attempt to discuss why the predictions from the 1990s were wrong. For example, we now know that dumping of heat and CO2 into the oceans is a bigger effect than originally modeled. In other words, thinking about the big picture, things are worse than was thought (because it means measures like putting up giant sky-mirrors aren't going to reverse committed warming as easily as they might).

Ultimately, he advocates technological fixes. For a more critical, but highly readable, look at this subject, see Michael Specter's "The Climate Fixers" from the New Yorker this past May: http://www.newyorker.com/reporting/2012/05/14/120514fa_fact_...

Had the OP read the New Yorker article, he might also understand that his references to "forbidden thoughts" are entirely unjustified. The thoughts he expresses are actually quite conventional, and widely discussed in scientific circles.

Even more ridiculous.. the full quote is:

"We might be able to setup space mirrors or otherwise increasing the reflectivity of our atmosphere. Obviously, we cannot hope to both keep pumping CO2 in the atmosphere, and correct for it afterward: this could quickly become economically infeasible."

In the context of killing the planet and the entire human race, we still mention a plan could be "economically infeasible".

Jeez.

Sigh.

We're not going to "kill the planet," or the entire human race. Humans adapt. That's what we do. That's why we won.

Such hyperbole endangers vital rational discourse on the subject.

A run a way process in which we loose all life on earth is not something I have read a lot of proof for. However, adapting to a changed climate may not be a pretty phase for the human race.

>We're not going to "kill the planet," or the entire human race. Humans adapt. That's what we do. That's why we won.

That is very close to the "fine tuning" argument often employed by creationists. It is entirely possible that humans have, in fact, merely been phenomenally lucky to have survived so far, and that the fact that we find ourselves as members of such a phenomenally lucky species is easily explained by the anthropic principle.

If you take all of the intelligent critters out there in the universe that are capable of discussing their adaptability, a pretty big chunk of those critters are going to be members of civilizations that got very lucky over the ages and managed to produce large cumulative populations, while a very small proportion will be critters from short-lived civilizations. Indeed, holding constant whatever level of adaptability we actually have, it is reasonable to assume that we are among the luckier of the civilizations at that level.

So no, we can't just assume that we're going to leap over any hurdle that comes our way.

Except that there are civilisations which have died out due to overexploiting their environment, or the climate changing and killing off their agriculture.

That's two risks. You can add others now which haven't previously been possible, such as disturbing your ecosystems to the point where there's another mass extinction looming, or changing the climate to the point where you spark famine, wars, lack of water, etc.

That's where all of the rational discourse backed by evidence (aka. science) is pointing.

I tend to give people the benefit of the doubt, and read economic arguments like that in the sense of "we will need to spend a large chunk of our civilisation's energy/material output to do this", not "Oh noes! My small, green pieces of paper!"

The thing that I worry about with the economic arguments is that the climate and/or ecosystems will reach a tipping point before we get to the point where we need to do something, and that chunk will be > 100%.

"As a sceptic, I'm quite sure that some kind of cool technology or another will make this not be a problem any more."

Seems legit.

Also wasn't that 0.3C in a nothing done to avert it scenario? With various green efforts around the world I would expect it to not quite hit the mark.

Despite all the green efforts, CO2 output from using fossil fuel still grows. Western economies barely, if at all, made a dent in their fossil fuel consumptions. Upcoming economies like China use more and more fossil fuels. I think its fair to say that we are nowhere near having a solution to reduce global CO2 output.

Then blame it on the economy gas use fell(or at least growth fell) significantly with the recession.

Not significantly. The CO2 PPM count is going up, recession or not: http://www.esrl.noaa.gov/gmd/ccgg/trends/global.html#global_...

Also, China is now liquifying coal.

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