Thursday, May 5, 2016

SteveF makes a hash of climate sensitivity; I propose a solution

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Over at the Blackboard they are hawking a “heat balance based empirical estimate of climate sensitivity” which delightfully uses the IPCC's own numbers to show that climate sensitivity has got to be low!!! OMG!!! 
I will show how the IPCC AR5 estimate of human forcing (and its uncertainty) leads to an empirical probability density function for climate sensitivity with relatively “long tail”, but with a most probable and median values near the low end of the IPCC ‘likely range’ of 1.5C to 4.5C per doubling.
And how is Steve going to do that? Well, he's going to give us both barrels of the lukewarmer shotgun, oversimplification and argument from incredulity.

Let's leave aside for today the argument from incredulity (in which his own method produces a fat tail of dangerously high climate sensitivities, and he says, basically, "but that can't be true, because hand-waving") and look at the oversimplification at the heart of SteveF's method for estimating climate sensitivity.
We can translate any net forcing value to a corresponding estimate of effective climate sensitivity via a simple heat balance if:
1) We know how much the average surface temperature has warmed since the start of significant human forcing.
2) We assume how much of that warming has been due to human forcing (as opposed to natural variation).
3) We know how much of the net forcing is being currently accumulated on Earth as added heat.
The Effective Sensitivity, in degrees per watt per sq meter, is given by:
ES = ΔT/(F – A)      (eq. 1)
That is fairly close to true, leaving aside changes in the albedo of the earth over time, and problems with taking the average temperature, which I discuss below. The chief problem is that he doesn't know any of those things with sufficient accuracy to constrain climate sensitivity in any meaningful way.

Climate scientists who do actual work with the climate are doing a fine job of reducing the uncertainty of these numbers, but in every case, the opening move is always to average available measurements over a period of time. But a heat balance model by definition requires accurate accounting of how much heat is coming in and how much is going out, and those numbers are changing over time.

How much has the average surface temperature warmed since the start of significant anthropogenic forcing? Right now, the answer is about 1.5C (not 0.9C, as Steve estimates). El Nino will subside and that number will (temporarily) fall, but that is beside the point: if you are using present-day forcings, then you have to use present-day temperatures.

The same goes for ocean heat uptake: if you are going to compare that to surface temperatures, you need to know what the uptake was at the moment when you took values for the forcings and the total warming. That's tricky, because we know ocean heat uptake varies significantly over time. It's lower than usual right now, because of El Nino, but how low?

If you are going to use ocean heat uptake averaged over X number of years (which to my understanding is basically mandatory to get any kind of an accurate number), then you also have to average the net forcing over those same years, and you also have to average the warming compared to preindustrial over those years.

But simple averaging still will not work, because heat loss varies with temperature to the fourth power. An average warming of +0.9C could reflect a steadily linear increase, or a long period of flat temperatures followed by a prolonged spike in temps to +4C. The latter will radiate more heat into space than the former. The average temperature is the same, but the heat balance is not the same. So we had better stick to instants of time if this method is to have any hope of delivering accurate results.

To reiterate: for an estimate of heat balance to give you climate sensitivity, you need the heat balance AT THAT MOMENT, not averaged over time. The amount of heat the oceans were absorbing ten or twenty years ago can only be compared to the temperature ten or twenty years ago, and the net forcing of ten or twenty years ago. If you are comparing the average heat uptake by the oceans since 1993 with the last 13 years of temperatures and forcing estimates from a moment in 2010, you are comparing apples and oranges. All of these things change over time, and to use the relationship between them to estimate climate sensitivity, only contemporaneous estimates can hope to be valid.

Consider a building occupied by an unknown number of people. You want to know how many people are inside. If you know how many people when in the building at midnight Tuesday, how many entered on Wednesday, and how many left on Wednesday, you know how many are in the building when Thursday dawns (assuming no births or deaths, nerds.)

On the other hand, knowing how many people started in the building, the number who left the building on Sunday, and the average number of people entering the building each day over the last year, doesn’t help you a hell of a lot. But this is what Steve has tried to do with his heat balance based empirical estimate of climate sensitivity.”

For this to work, do you need to use the present moment? No, you do not. In fact, there may be excellent reasons to use some instant in the past, such as the benefit of hindsight in estimating warming or forcings or the presence of an exceptional event (like a large volcanic eruption) that lets you really test some of your theories about forcings and heat balance and temperature.

In other words, you need a series of “moments,” for which you estimate the levels of various forcings and the heat uptake of the oceans. Then you can predict what the temperature “should” be, based upon the inputs, and compare it to what the temperature was (and is.)

Since the act of resolving the state of the climate in each of these moments is one fairly powerful method of determining the inputs for the next “moment” (and whether it can do so, compared to historical observations, is a good test of how accurate it is) we might want to calculate a series of moments, each derived from the one before, based upon our best estimates of forcings, ocean heat uptake, and the like. 

Since everything we said about average temperatures over time could also be said about temperatures averaged over the global surface (i.e., that different local temperatures can yield the same average, but different heat loss) we had better break the earth into boxes, or "cells" and calculate temperature, heat uptake, heat loss, etc., for each cell.

Not all the same color
 

With these modest adjustments the calculations will have a much better chance of doing what Steve wants them to do, which is to take measurements of the climate system, account for ocean heat storage, and estimate climate sensitivity.

I call it a climate model. Trademark pending.

Wednesday, April 27, 2016

Punch-drunk with warming, WUWT branches out to being wrong about Palestine

2014 was the warmest year on record. Until 2015. 2015 looks to hold the title until 2016 goes in the books. Massive coral bleaching, accelerated sea level rise. To paraphrase Cedric Coleman, it's hard out there for a denier.

Eric Worrall of the monkey house tries to paper over the gaping hole in the movement's foundation with a "jazz hands" routine about Mahmud Abbas, who took the opportunity presented by a UN signing ceremony for a climate accord to call out Israeli settlements in the occupied territories:
"The Israeli occupation is destroying the climate in Palestine and the Israeli settlements are destroying nature in Palestine," Abbas told the gathering of 175 countries signing a landmark climate deal.
Eric chooses to pretend that Abbas claimed Israeli settlements cause global warming:
 Regardless of your position on the Israel / Palestine situation, suggesting that Israeli settlements contribute significantly to global warming is utterly implausible.
Which of course is probably why he didn't say that. He said the occupation was damaging the environment in Palestine, which it most certainly is. Israelis have established over 200 illegal settlements in the West Bank alone. These communities establish themselves strategically to control resources or strategic points and to restrict the development of Palestinian communities. They are not established via any rational planning process, which would certainly not place hundreds of tiny towns, some just campers and trailers running off diesel generators, scattered over thousands of square kilometers. This is indeed destructive to the environment in the West Bank.

Saturday, March 12, 2016

Lucia's sadly selective statistical showpersonship

Lucia Liljegren is spending the twilight of lukewarmism as a non-laughable position mostly posting recipes, and notifying her followers about the arrival of major holidays (three of her last ten posts.) But 'twas not always thus. During the "hiatus" Lucia was fond of comparing the IPCC's multi-modal mean with global temperatures, despite the fact that these were models of climate, not weather forecasts, and that patient people had explained to her over and over that "about 0.2C/decade over the next several decades" was not a prediction one could falsify based on a few years of data.

She liked making this mistake so much, she did it again and again and again (and again and again…and again.) But this all stopped rather abruptly in November of 2014, which funnily enough was exactly the time El Nino came to a stuttering start after a unprecedented 50-month absence:


As a result, every month after November 2014 (anomaly 0.68C) has been hotter (anomaly-wise) than November 2014 itself:

And yet despite the rather dramatic turn in the data, and despite the fact that she liked making this comparison well enough to make it over and over again with different temperature records and updates to the present, she never updated her final graph, which looked like this:


Why did Dr Liljegren suddenly lose interest in this exercise? Why the statistical-torture hiatus? We may never know, but said graph with more recent GISTEMP measurements superimposed looks like this:



It's a mystery, really.

UPDATE: MartinM has better graph-fu than I and has updated lucia's graph of the multi-model mean vs the 13-month mean.

 

Monday, January 4, 2016

Announcement of new elements allows WUWT dittoheads to flex their ignorance

Every now and again, Anthony likes to cut-n-paste a science press release, to try and delude himself and his readers into thinking his website has something to do with science other than whining about it. Unfortunately, changing the subject merely serves to illustrate the pathetic science illiteracy and reactionary politics of his little band.

Recently actual scientists were able to synthesize four new elements -- creating materials never seen on earth before. And Anthony, "citizen scientist," was able to copy their press release!

This should be easy. Not much is required of the commentors by way of response here. Scientists toiled for years in obscurity and today they leave their mark on history. Yay science! Unfortunately, this simple PR exercise is beyond the ken of Tony's tinfoil hat brigade.

Needless to say, "just get past…around 110" is not anyone's idea of how to synthesize stable superheavy elements, which is still very much a thing. But perhaps I am getting sidetracked from "JPS"'s main point, which seems to be: Scientists were wrong about an island of stability (wrong) so global warming is a lie!

Multiple dim bulbs simply reject the idea that anything has been discovered. It's just another hoax!



"Mark" one goes off on a weird tangent about element names, but "Mark" two stands ready to pull the discussion back to what the site is all about:

Having belittled homosexuals, the tinfoil hats decide it's time to bring up slavery and the New World Order:




I'd like to reiterate: this is a puff piece about a feel-good story about the discovery of new elements. But these deniers can't get through a simple press release on a totally non-climate-related subject without devolving into an anti-intellectual, homophobic, paranoid cri de coeur. It does not make one hopeful for their output of the course of the rest of this, an election year.

Monday, December 14, 2015

GISTEMP November: +1.05C

h/t Gavin Schmidt, via Twitter


Another month, another record. 2015 is now all but certain to go into the books as the hottest ever, claiming the title from 2014(!)

We are in the grip of a strong El Nino, so the coming years will likely see some regression towards the mean. I fully expect to see a "no warming since 2015" denier talking point by mid-2017 at the latest.

Beneath the noise, the world will continue to warm.


Wednesday, November 18, 2015

Intolerant protest and the lantern



Obstreperous protests are roiling campus at elite universities throughout the nation. At Dartmouth, a Rosa Parks for a new generation screamed “Fuck you, you filthy white fucks!” at students studying quietly in the library. At Yale, protesters fought for sensitivity and racial understanding by spitting on people. At the University of Missouri, protesters made nation news by variously harassing, threatening, and assaulting journalists trying to cover protests taking place in public on an open quad.



The debate over this behavior has unfolded predictably, with those on the hard left trying to draw our attention to the racial problems on these campuses and in society at large which inspired these protests (although the specific offenses cited can seem rather underwhelming) and the right professing simple outrage, unalloyed by any hesitation related to the age of these protesters, the nature of the problems being protested, or the difficulty of growing up and fighting for what you believe in in the era of cellphone cameras and outrage politics. Charges of fascism are leveled, indicating we are in a day whose name ends in a "y."

But both sides, it seems to me, are glossing over the key question which screams out from any reasonable mind reviewing these actions: What on earth were/are these people thinking? Why are people acting in reasonable and inoffensive ways -- people like Tim Tai, Nicholas Christakis and Ericka Christakis, and Tim Wolfe -- the targets of such fury and contempt?

Not for any acts of racism they have committed, for they have not, in the main, been accused of any. Not for any anger or contempt they showed themselves, as may naturally spark anger in return, as those we have on video confronted by protesters (all except Ericka Christakis, and we have her e-mail for comparison) exhibit almost preternatural patience while accepting horrible abuse.

The anger we are seeing, which at a few removes seems utterly disproportionate to any offense offered, is it seems to me best understood by looking at the dynamics of group hysteria -- specifically the way hysteria is deployed by groups to enforce conformity. EM Forster alludes to this in at a key moment in A Passage to India:
But the Collector looked at him sternly, because he was keeping his head. He had not gone mad at the phrase "an English girl fresh from England," he had not rallied to the banner of race. He was still after facts, though the herd had decided on emotion. Nothing enrages Anglo-India more than the lantern of reason if it is exhibited for one moment after its extinction is decreed.
It is sadly apparent that the behavior Forster attributes to Anglo-Indians can be seen in any community, but particularly a tightly-knit community with a strong sense of its own values (a strong sense which perhaps tends to be the stronger when people are conscious that those values may not be shared by all.

It is clear that the protesters believe that this is a moment of great crisis, of emergency, and they believe that they are subject to awful persecution as part of the larger problems of racism, sexism, ableism, etc., which are (as always) worse than ever before. Both the belief in the moment of crisis and that things are catastrophically bad have become markers of group identification for the protesters.

In this context, it does not take anger, or racism, or even indifference to the cause to spark rage. All it takes is a refusal to accept the tacit assumptions they we are in the midst of a crisis of the marginalized, legitimizing the most extreme passions and before which other concerns or other contrasting values or aspirations are but leaves blown about in the howling storm of righteous rage.

To politely remonstrate with the representatives such a community may enrage them more than anything; worse than a defiance of substance, those trying to address the protesters calmly and maintain a sense of proportion are guilty of a defiance of a collective mood. Once again the lantern of reason irritates and provokes those who have decreed its extinction.

This behavior is never laudable, though perhaps one could make an argument for it as one of many characteristics of groups which are morally and ethnically not defensible but which strengthen groups against hostile outsiders and, thus, are persistent. But its use here is particularly pointless and self-destructive, or, to quote another fine English novelist, "as frivolous as the application was ill-judged."

How are these tactics wrong? Let me count the ways. First, this sort of bullying emotional hysteria is by its very nature a tactic of majorities. And while the advocates of political correctness may form a majority of sorts on some campuses, in the wider society they are anything but. And the wider society is ultimately the place where decisions about funding, about regulation, about things such as whether affirmative action will continue to exist are taken.

Second, these protesters have chosen their enemies exceptionally poorly. Choosing the right enemies, and encouraging them to express themselves in the right way, is a critical part of what makes protest successful. Police dragging a tired old woman off a bus at the end of a long day's work; Bull Connor with his fire hoses and his police dogs; the comically evil hatred of the Westboro Baptist Church.

Compare, say, Ericka Christakis, whose firing the Yale protesters have written into their demands:
I don’t wish to trivialize genuine concerns about cultural and personal representation, and other challenges to our lived experience in a plural community. I know that many decent people have proposed guidelines on Halloween costumes from a spirit of avoiding hurt and offense. I laud those goals, in theory, as most of us do. But in practice, I wonder if we should reflect more transparently, as a community, on the consequences of an institutional (which is to say: bureaucratic and administrative) exercise of implied control over college students.
There is more to Christakis' letter, but it is all of a piece with the above; measured, judicious, a little bit boring; a liberal arts academic doing exactly what anyone who has spent five minutes with a liberal academic knows that they do: they take a concept or accepted line and "problematize" it. That's virtually their raison d'etre.

This was the e-mail that promoted the student in the first video to scream "You are disgusting! You should not sleep at night!" (They also decided to yell at the husband for something his wife wrote, which is an…interesting…choice for radical social justice advocates.)

This is worse than an error: it's a mistake. Protest, as Gandhi so succinctly expressed it, is about defeating physical force with spiritual force. It is about creating a moral story which is compelling to people on the outside of the dynamic. In this, these protests have failed spectacularly.

Protesters by their very nature don't have more physical (or legal or financial…take your pick, depending on the circumstances) power than their opponents. If they did, they would simply impose their will. So protest is inherently a matter of fighting a stronger opponent. To fight someone stronger, you have to be smarter. You have to be more disciplined. You have to pick your battles carefully and with an eye to the wider public who are not directly engaged. Because whether a rebellion is violent or nonviolent, they mostly share this feature: those that do not acquire external allies will fail.

I see few of these qualities in the current protests. They seem unable to acknowledge that while they may be discriminated against in important ways, that they are also, as students of elite American colleges, very privileged in their own right. They seem to believe they can bludgeon their teachers and their peers with hysterical anger at the slightest deviationism, and yet not spark a backlash.

Instead of focusing their outrage on the horrific racism and other disgusting offenses against modernity with which our society is amply supplied (see any GOP candidate for president), they stay snug and secure on campus, selecting targets of opportunity who on a political correctness scale of one to ten, would on their worst day score no lower than a seven. Rather than focus on police violence or income inequality or lack of representation in government or corporate America, these protesters demand "free expression" posters be prohibited -- and that they be excused from classes missed while protesting.

I am over forty, so take what I say about the young and their methods with appropriate skepticism. That being said, the Christakises are still in their jobs, Tai is still taking photographs, and reeducation classes for dissenters are still just a (disturbing) twinkle in PC eyes. I suspect we have seen the high-water mark of this particular wave of campus protest, and the academy's final verdict will be: "You have widely mistaken my character, if you think I can be worked on by such persuasions as these."


Wednesday, October 28, 2015

Radiation risks of the Fukushima nuclear accident, expressed as slices of bacon

If we must die . . .

Because I apparently enjoy banging my head against brick walls and similarly productive activities, I commonly place myself in the path of rampaging internet mobs, calling for humility, moderation, and tolerance (hypocrisy being one of my other defects of character.)



Nuclear energy in the United States is, by far, the largest single source of low-carbon energy. Nuclear energy production has been flat in the United States for the last ten years, even as the need for more low-carbon electricity has become screamingly apparent, partly because these plants tend to be expensive and can take a very long time to build, but in large part because these plants are very unpopular, due to fear of nuclear radiation.

Nuclear kWh -- flat as a day-old soda

Nuclear advocates don't always respond to these concerns in the best way. Besides pointing out that these risks are often overstated, a fair number of them foolishly try to deny that ionizing radiation from nuclear accidents or improperly stored waste could cause any harm at all, justifying that counterintuitive conclusion with misreadings of the epidemiological literature or with reference to pseudoscience like radiation hormesis.

The truth is that the cancer risk of low-level exposure is real, but very, very small. Since the cancer risk of red and processed meats are in the news -- sometimes being similarly exaggerated -- I wondered if one could express the risks of the Fukushima nuclear accident in terms of an equivalent number of slices of bacon.

Ten thousand people living close to the Fukushima plant, tested in this study, were exposed to as much as 1.07 mSv of internal radiation (one person) [1]. The average was less than that. They don't directly give the average or the means to calculate it in the paper, but judging by these graphs, and by the fact that two-thirds of adults had no detectable internal radiation exposure at all, we can estimate the average at less than 0.25 mSv. One mSv carries with it an additional risk of death from cancer of 0.005%.

Doctors and researchers are still trying to sort out the cancer risks, if any, from non-charred red meat. Processed meats, like bacon, are definitely associated with distal colon and rectal cancer. There may be other cancer risks, such as gastric cancer, but these are so small that scientists are still arguing about them. The only significant risk (other than that associated with excess calorie consumption, i.e., obesity and its diseases, and hypertension from excess sodium in susceptible individuals) is from colorectal cancer. Two slices of bacon per week carry with them a 47% increase in the risk of death from colorectal cancer, which in Americans is 15.5/100,000 = 0.0155% risk of death.

0.0155% * 0.47 = 0.007285%

But this is meat consumption over the long term, so we will give our hypothetical colon cancer victim 30 good years of bacon consumption before succumbing -- 0.007285/(30 * 52) = 0.00000466987% excess risk of death from colon cancer per serving. 1 mSv is approximately 0.005%, so 0.00005/
0.0000000466987 = 1070 slices of bacon.

One civilian in the "hot zone" at Fukushima was subjected to an excess cancer risk comparable to three slices of bacon with breakfast daily for a year. The average exposure in the hot zone was on the order of two slices daily for four months.

I suggest slices of bacon as a new standard method of describing radiation risks from nuclear energy. Real, but small. 

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1. External exposure is more variable and harder to measure, but this study found 2/3 of external exposures were less than 1 mSv, and 98% were less than 10 mSv. 10 mSv is a good bit of bacon -- 3 slices a day for ten years -- but still less than a single abdominal CT. 98%, again, were below that, and 2/3 were less than a tenth of that.