Over the years I have pointed out the fallacious arguments of climate change deniers when they attack legitimate climatologists like James Hansen and Michael Mann. This is, of course, like kicking at a bee hive, and whenever I do the comments section of my posts fill with lots of angry buzzing.

But now, for what I think is the first time, I find myself the target of an attack. And I have to admit, I welcome it: it’s a textbook case of denialist sleight of hand, of distraction, distortion, error, and misdirection.

Stick around for all of this. It’ll be… interesting.

Our story so far

OK, first, here’s the scoop: a few days ago, I wrote a blog post taking apart two intellectually bankrupt climate change denial articles, one in the Wall Street Journal, and the other in the UK’s Daily Mail. Both were claiming that global warming appears to have stopped in the past few years, a claim which is trivially easy to show wrong. In fact, I linked to two articles doing just that: one at Skeptical Science, and another I myself wrote. Finding actual scientists destroying that claim is not hard at all; those two links have many more links therein.

In my post about the WSJ and DM, I included a graph. It pretty clearly shows temperatures rising from 1973 to the present. And this is where the fun begins.

That’s the plot. It’s from a recent, independent study done at Berkeley, and represents actual, measured, data. Just to be clear, those points are from weather stations across the globe, and the method used to collect and analyze those measurements is described by the Berkeley team themselves (PDF). With me so far?

Apparently, William Briggs is not with me. He takes very vigorous exception to the graph in an article he wrote which he titled "Bad Astronomer Does Bad Statistics: That Wall Street Journal Editorial." I encourage you to read it, so that you can assure yourself I am not misrepresenting his arguments in any way.

I found out about this article when I saw a tweet by Dr. Briggs himself. My first thought was: Uh oh. I sure hope I didn’t make a math mistake somewhere in my WSJ post! I better read Briggs’ article and see… So I read it.

My next thought after reading his arguments was then: Ho-hum. So?

The mismeasure of an argument

Basically, Briggs accuses me of not understanding statistics, of not including error bars, of misrepresenting that points in that plot, of not displaying the plot correctly, and so on ad nauseum. His biggest claim: that those points aren’t measurements at all, but estimates.

Here’s the thing: he’s wrong. Those point are in fact measurements, though they are not raw measurements right off the thermometers. They have been processed, averaged, in a scientifically rigorous way to make sure that the statistics derived from them are in fact solid. The Berkeley team describes in detail how that was done (PDF), and does actually call them estimates, but not because they are just guessing, or using some arcane computer model. They are technically estimates, in the sense that any measurement is an estimate, but they are really, really good ones. Greg Laden tears this use of words apart, as well as pretty much everything else Briggs wrote.

Oddly, Briggs then goes on to call them "predictions" for some reason, and that they came from "models", which is just weird. It’s as if he’s trying to use a word choice that raises doubt about the measurements. But again he’s wrong. They really are measurements, not model predictions. At Open Mind, Brigg’s word choice once again is ripped apart. [Note: Briggs has left a comment there, further verifying the fact that his use of words is incorrect.]

This reminds me of one of my favorite skeptic jokes. Question: How many legs does a dog have if you call its tail a leg?

Answer: Four. It doesn’t matter what you call a tail, it’s not a leg.

There are many other places where Briggs makes mistakes that render his arguments null; for example, the error bars (what statisticians usually call "uncertainty") are in fact made available by the Berkeley team, and are small compared to the long-term rise in temperature. For another, Briggs says I should’ve shown the plot going farther into the past, because 1973 was actually a low point. However, that’s completely wrong: it’s actually a high point! As Deep Climate points out here, this actually makes the warming trend lower. So in true contrarian fashion, Briggs is contrary even to himself. It’s bizarre.

So really, there goes Briggs’ argument. His main point is wrong, so we’re done, right?

Well, no. There’s more fun to be had here.

Beside the point

If you read Briggs’ article, you certainly get the impression that because the graph I use is statistically meaningless (so he incorrectly claims), then my whole argument about global warming is wrong.

And this is where I found myself greatly amused, though in a schadenfreude sort of way.

Think of it this way: if my argument hinged on that graph, and I removed it, my argument would have no foundation, correct? It would change the tenor of the entire blog post.

Go look at my article. If you remove that graph from it, what changes? Nothing. My main point — that the WSJ and DM articles are wrong, that we have lots of evidence the Earth is warming up, that 9 of the 10 hottest years on record occurred since the year 2000, that the DM article specifically uses scientific studies and presents them as if they say the exact opposite of what they actually say — still stands.

So even if that graph is wrong and misrepresents what I’m saying — which it does not — it doesn’t matter. In fact, I used that graph as an illustration, to show how we’re warming up. I never intended it to be the basis for the argument I was making, just a way of further showing it. If you read the actual words I wrote, including the links to many, many articles backing up my position, you’ll see that Briggs has not refuted a single actual point I made.

So even if he’s right about that graph, it doesn’t matter. And he’s not right.

But notice what he’s done. He’s taken what is clearly a minor point and blown it up as if it’s my main point. He’s used shady words (predictions, models) to cast aspersions, and to make someone (me!) look bad. Then, by "refuting" this minor issue he can then poison the well, strongly implying that all my arguments are wrong. That’s kind of a big no-no when trying to argue a point.

But it packages well. Watts Up With That, another denialist blog, has run with Briggs’ claims about me as well. He also makes the false claim that warming has stalled, and so on. Note WUWT also says the signers of the WSJ OpEd are "16 scientists", which isn’t true: not all are scientists, and only four have actually published climate science research. And don’t forget about the article the WSJ refused to print talking about the reality of global warming, signed by 255 actual scientists.

Oops.

Denialism’s dark mirror

I will admit the irony of this attack amuses me greatly; Briggs accuses me of many things he himself is doing. That is standard fare from antiscience group: creationists, global warming deniers, and alt-medders, for example, all seem to project their own tactics on the scientists with whom they disagree. Don’t like real medicine? Accuse scientists of being in the pocket of Big Pharma (and forget about the millions being made by quacks on useless "remedies"). Don’t believe in evolution? Accuse scientists of being too dogmatic. Don’t think global warming is real? Accuse scientists of misrepresenting the data.

My favorite irony is that a lot of these global warming denialists take money from fossil fuel interests, but then routinely say to "follow the money", as if it’s the climatologists who are raking in the big bucks from shady think tanks with undisclosed bankrollers. While Briggs points out he gets no money from them, he asks where my money comes from. Think on this, Dr. Briggs; how much money would I make if I suddenly turned coat and said global warming wasn’t real? I’ll guarantee you it would be a lot more than I make now, probably with a couple of zeroes added to the end. So that argument falls a wee bit flat here.

Like all the others.

Of course, given the comments I’ve seen on my blog, on Briggs’ blog, on Watts Up With That, or in any other blog discussing global warming, I know how this will go. You can bring up the major pieces of evidence supporting reality again and again, but the denialists will ignore them and go after phantoms instead. Because if they do acknowledge the actual evidence, they lose.

In 2015, NASA’s New Horizons spacecraft will zip past Pluto, giving us our first close-up view of this tiny world.

The team behind the space probe have a nice idea to help raise awareness of it: make a new US Post Office stamp commemorating it. My friend Dan Durda, both an accomplished astronomer and artist, created this lovely design of the stamp:

[Click to enhadesenate. Note: the word "Forever" means the stamp is always good for first class postage, and is crossed out here to prevent forgery.]

It shows the spacecraft going by Pluto and its (relatively) freakishly large moon Charon. I like how he didn’t go for photorealism, but instead used an oil paint-like feel for it. The stamp is meant as a followup — I might even say send-up — of a US stamp issued in 1990 about Pluto that has the label "Not Yet Explored".

I like this stamp! I’d love to see it made official, too. Alan Stern, the head guy for the mission, created a petition to help that along. It takes more than just a nice stamp design to get the PO’s notice; it has to have public support as well. I signed the petition, and if you want to, please do.

I’ll note that I expect this to raise the specter of whether Pluto is a planet or not. I have some thoughts on that, and I’ll be posting again soon on that topic.

Over the course of several hundred years – most notably in the 17th and 18th centuries — winter temperatures in western Europe were much lower than normal. Glaciers came much farther south than they had before, and a famous painting shows people ice skating on the Thames river — which hasn’t been frozen since. The period is known as the Little Ice Age, and its cause has always been something of a mystery.

However, new research by scientists at the University of Colorado-Boulder (yay team!) may have pegged it: the LIA appears to have started abruptly in the late 13th century, between the years 1275 and 1300. Radiocarbon dating of plants from Baffin Island (north of the Hudson Bay in Canada) and sediment samples from a lake in Iceland indicate that there was a rapid onset of severe cooling at that time. It’s been thought that the cooling started around then, but it’s been hard to pin down until now.

More importantly, this narrows down the cause of the LIA: four tropical volcanoes erupted violently in that period. The ash would have darkened the atmosphere, letting slightly less sunlight down. Some of the gases emitted by volcanoes also cool the air. It seems clear these volcanoes are what triggered the Little Ice Age. But why did it last so long?

That may be due to what happened after the volcanoes erupted. Most likely, the warmer temperatures would have melted the north polar sea ice. This fresh water is less dense than salty water, so it would flow on top of the oceans, and wouldn’t have mixed well with the deeper water. This would have slowed the transport of heat from the equatorial waters back up north, cooling them further. That system is what maintained colder temperatures for so long. There were variations — the Ice Age was more of as series of pulses of temperature drops than one long period — but for centuries the heating of the Earth was disrupted in that region.

For a long time it’s been suspected that the Sun played a role here, too. During the period of 1645 to 1715 there were few or no sunspots, a time called the Maunder Minimum. Sunspots are dark, but they’re surrounded by a region, a rim, that emits strongly in the UV. These faculae, as they’re called, actually more than make up for the darker regions of the spots, so in reality sunspots add to the amount of light and heat the Earth receives, by a fraction of a percent. So an active Sun, it’s thought, may warm the Earth a teeny bit more.

Read the rest of this entry »

Thanks to astronaut Ron Garan on Google+, I was alerted to some amazing footage of the Moon setting as seen by astronauts on board the International Space Station. I uploaded it to YouTube and added some comments to show you something really cool…

[Set it to high-def and make it full screen!]

Astonishing, isn’t it? As the Moon sets, you’re seeing it through thicker and thicker air. The air acts like a lens, bending the light upward. The part of the Moon nearer the Earth’s limb gets bent up more, so the Moon looks like it’s getting flattened. Watch it again; the top of the Moon doesn’t appear to be affected much. It looks more like the bottom slows down and the top pushes into it. You can read about this effect in more detail in an earlier blog post.

Weirdly, as I watched the video, it looked very much like the whole Moon was shrinking as it set, as if it were receding rapidly. When I saw that I knew intuitively that couldn’t be real; the ISS is only moving a few thousand kilometers over the time this whole video was taken (about ten minutes), not nearly enough to see that big a change in the size of the Moon. It’s 400,000 kilometers away, after all! So I measured the size of the Moon on the screen, and incredibly the width doesn’t change. Do you see it appear to shrink too? It’s an illusion!

Funny how our brain interprets such things. As if seeing a gigantic rock moving through the sky while perched on board a football-field sized satellite moving at 30,000 km/hr isn’t weird enough!

Credit: Image Science and Analysis Laboratory, NASA-Johnson Space Center. "The Gateway to Astronaut Photography of Earth".

[Note: Every week I hold a live video chat on Google+ where I answer questions from readers. I call it Q&BA, and when I get a question that stands alone, I'll make it its own video. ]

A lot of people, it seems, have morbid thoughts about space. Why else would I get asked this so much: "What would happen to the human body exposed to the vacuum and cold of space?"

Of course, this sort of thing is depicted in scifi movies a lot, and people are curious about it. And even though the movies always get it wrong — you don’t explode, or freeze instantly — it does make folks wonder about it. And while the reality isn’t maybe as gooey as in the movies, it’s still pretty nasty.

I wrote about this in my review of the movie "Mission to Mars", as well as answering a question many years ago from a reader. And even though it’s an icky thing to think about, it does give me a chance to talk about heat transfer, which is pretty, um, cool.

Well, this is depressing: Fomalhaut b may not exist.

Fomalhaut is one of the brightest stars in the sky, and is only about 25 light years away — that’s close, on a cosmic scale. It’s young, not more than a few hundred million years old, and surrounded by a vast ring of dust, leftover from the formation of the star itself. The ring is about 20 billion km (12 billion miles) in radius, and has a sharp inner edge.

That last bit is important: the easiest way we know to make the inside edge that well-defined is if a planet is orbiting the star just inside the ring. Its gravity would draw in particles, sculpting what would otherwise be a fuzzy boundary into a clean-cut ring. Not only that, but the ring is off-center; again, that’s likely due to the gravitational influence of a planet.

In 2008, astronomers announced they had found that planet: it appeared in two different Hubble Space Telescope images (shown above; click to embiggen) separated by two years. During that time, it had moved a little bit, by just what you’d expect for a planet at that distance from the star. The news came out the same day as other planets were seen around a different star, and I, along with lots of other folks, made it a headline (see the gallery at the bottom of this post showing all the planets we’ve been able to detect directly in images). This was, after all the first direct detection of a planet orbiting a Sun-like star!

Except, maybe not so much. A new paper has come out (PDF) trying to see Fomalhaut b using the Spitzer Space Telescope. Spitzer is sensitive to infrared, where the planet is far brighter.

And what did they see? Nothing.

Dang.

This image is pretty damning for the existence of Fomalhaut b. It’s the Spitzer infrared observations of the star, with the star’s light carefully removed. On the left is the actual image, and on the right they artificially added a point of light calculated to be equal to what the planet would emit, in the same position the planet should be — that’s what Arrow 1 is pointing at. It should be one of the brightest things in the image (Arrow 2 points to an unrelated bright spot). And while it’s obvious on the right, nothing can be seen on the left, in the real image. In other words, the planet isn’t seen.

Dang again.

Looking over the paper, it’s clear the astronomers were very careful, and did a number of tests. There’s no known way to make a planet as bright as what was seen in the Hubble images yet invisible in the Spitzer images. If the planet were there, they should’ve seen it. Also, a recent study has shown that if the two images show the planet moving, it would be on an orbit that crosses the ring! That seems extremely unlikely, if not outright impossible. A planet that big and massive — more massive than Jupiter — would disrupt the ring in short order if it physically crossed it. That really does make it very, very likely this is not a planet^*.

So what is it? It’s probably a clump of dust orbiting the star, reflecting light from the star enough to show up in the Hubble images but not warm enough to show up in the infrared observations.

That’s too bad. If this is true — and it probably is — then that takes away one of the very few planets directly seen in telescopic observations. However, there are still plenty more, and those have been confirmed (again, see the gallery below). And that number will tend to increase as time goes on, even if every now and again it drops by one or two.

Hmph. I once wrote that destroying a planet is hard. Sometimes, all you need to do is try to observe it a different way, and poof! It’s gone.

And now I have to update that gallery, and all my previous pages about it too. Dang science. Always learning more stuff and changing what we thought we knew.

Image credit: Paul Kalas, U C Berkeley; NASA/Spitzer/Markus Janson et al.

^* I chatted with an astronomer friend of mine about this, and he agreed with the authors of this new study. "Overall," he wrote me, "it smells like fish.". I couldn’t help myself. I wrote him back: "Of course it does. Fomalhaut is the brightest star in Pisces!"

[Below is a gallery of exoplanets that have been directly imaged using telescopes on ground and in space. Click the thumbnail picture to get a bigger picture and more information, and scroll through the gallery using the left and right arrows.]

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A few years ago, I started doing a weekly video question-and-answer session I called "Q & BA". It was a series of short videos that were a lot of fun to make. Unfortunately, the overhead got to be too high — it took all day to edit them! — and I had to stop.

But now, Google+ has changed that: Hangouts On Air is a feature that allows me to go on camera and broadcast a live video chat session to an unlimited audience. I take questions via Twitter and G+, and it’s a lot of fun. It lasts about an hour, and I put the whole session on YouTube. But some of the answers stand alone, and it’s easy to extract them out, package ‘em up, and post ‘em by themselves.

So I’m very pleased to announce I’m starting the series again! The first Q&BA is a great question: "What’s the best way to get kids into science and skepticism?" — what better way to get the series going again? Enjoy.

I’ll be posting more of these, maybe even one per day as time allows. If you like them, please give them a thumbs-up on YouTube, and drop by the Q&BA Hangout when I do them live! I announce them on Twitter and G+, so follow me there and stay up-to-date. Also, I have an archive with links to all the videos. Thanks!