Sunday, May 29, 2011

Scientific Skepticism

Prompted by a recent talk by a respected paleontologist, I’ve been thinking about skepticism and science.  This scientist observed that “science is a process of competing models” focused on identifying “which model is least wrong.”  It seems to me that, with its stress on degrees of “wrongness” in accepted models (read theories), this definition embraces a kind of skepticism that is central to science.  It’s part of the ongoing testing that moves science forward.  Importantly, this isn’t reflexive nay-saying or denying.

In an interview in the most recent Scientific American (“I Stick to the Science,” interview by Michael D. Lemonick, June, 2011), Lawrence Berkeley National Laboratory physicist Richard Muller, a strong critic of past reports on global warming, responded to the question Do you consider yourself a climate skeptic?,
No – not in the way that the term is used.  I consider myself properly skeptical in the way every scientist should be. . . .
Muller’s adherence to this kind of skepticism is bracing.  He leads the Berkeley Earth Surface Temperature (BEST) project which, in an effort to address alleged biases in previous analyses of land surface temperature measurements, has gathered and analyzed a much more complete set of temperature data than heretofore assembled.

In March of this year, he testified before the House of Representatives Committee on Science, Space, and Technology and apparently “enraged climate skeptics” (Scientific American, June, 2011) because he didn’t endorse their orthodoxy.  Instead, he told the Committee that a preliminary analysis of BEST data showed a climate warming trend “very similar to that reported by the prior groups:  a rise of about 0.7 degrees C since 1957.”  In measured words, he concluded:
Despite potential biases in the data, methods of analysis can be used to reduce bias effects well enough to enable us to measure long-term Earth temperature changes.  Data integrity is adequate.  Based on our initial work at Berkeley Earth, I believe that some of the most worrisome biases are less of a problem than I had previously thought.
I spent some time earlier this week watching the webcast of that Science Committee hearing on climate change.  An interesting and frustrating experience.

I had one surprise – the diversity of opinion that the Committee brought together.  Not what I expected from a committee chaired by a member who very clearly resides in the camp that nay-says climate change and significant human contribution to it.

Over the years, I’ve attended many U.S. Congress hearings and know it’s seldom a satisfying experience.  Constructive exchange rarely marks the interaction between witnesses and members.  But the most frustrating attribute of most hearings is the inarticulateness of many members of Congress.  This House Science hearing easily fit the mold.  Regardless of where one stands on the issues of global warming, the quality of nearly all of the questioning (and badgering) by House members, whether Democrat or Republican, liberal or conservative, yea-sayer or nay-sayer on global warming (these days these three distinctions are pretty much synonymous), left much to be desired.  Further, the kind of skepticism largely on display on both sides in the hearing was of the common political variety – an instinctive and destructive distrust of the motives and accuracy of folks making assertions with which you disagree.

It made me wish to turn the clock back to the time when Sherwood Boehlert, a Republican from upstate New York, served on the House Science Committee.  Boehlert had a long career in the U.S. House of Representatives (1983-2007), spending the entire time on the Science Committee which he chaired beginning in 2001.  Boehlert (pictured below) dealt with many thorny issues in science, including climate change.  (This congressional photo of a press conference is in the public domain and, no, despite what's on the lectern, he didn't serve in the Senate.)

Convinced that global warming was real and merited a public policy response, the moderate Boehlert would clearly be at odds with the Republicans who now control the Science Committee.  But it’s not just his position on that issue that strikes a sharp contrast between him and his successors.  Boehlert brought an incredible degree of intelligence to bear on the complex issues he worked on.  He could deal with subtlety and weigh competing arguments.  I think he appreciated the kind of scientific skepticism that Richard Muller espouses.

And here’s the real attraction for me, as a political figure, Boehlert was singularly articulate.  I remember him once comparing the negotiations that had been taking place among several House committees to the relationships between various countries in Europe during the 19th century.

Indeed, how can you not appreciate a politician who, in a speech on climate change, could quote both Woody Allen and Wendell Phillips (the abolitionist)?

In his address to Climate Institute’s Washington Summit on Climate Change (September 20, 2006), he used Allen for some gallows humor.  (The speech appears in the Science and Politics of Global Climate Change blog.)  He told his audience,
Climate change discussions can be consumed by gloom. They can remind me of the opening of Woody Allen's classic essay, "My Address to the Graduates." It starts: "Today, we are at a crossroad. One road leads to hopelessness and despair; the other to total extinction. Let us pray we choose wisely."
Then, he topped Allen with a very dry comment,
I think our choices are a little better than that, and if they're not, we'll never win over the wider public.
Later in this address, Boehlert invoked Phillips in order to advise scientists to be careful and thoughtful in bringing their messages on climate change to the public.  Sound and measured words that many apparently did not heed.
The abolitionist Wendell Phillips famously said, "One man on the side of God is a majority."  But while that no doubt got Phillips through some lonely times, the anti-slavery advocates didn't gain political influence until they won more converts.
So scientists have to engage.  And what scientists say needs to be clear and accurate and modulated and persuasive.  Hyperbolic claims will only diminish scientific credibility over time.
Scientists have to be clear about what we know, and about what we don't.  They need to be "up front" about uncertainties - and about the potential costs of waiting until all uncertainties are resolved.
Amen.  We need more Sherwood Boehlerts.

By the way, according to The American Heritage Dictionary of the English Language (3rd edition), the Greek word from which we derived skeptic is skeptesthai.  It means examine.

Tuesday, May 17, 2011

One Other Thing About John Wesley Powell

When school teacher and principal John Wesley Powell (1834 – 1902) joined the Union Army at the outset of the Civil War, he did not put aside his deep interest in natural history, particularly geology and paleontology.  Indeed, his self-taught geology formed the basis for his role in the army as a military engineer.  It’s that experience of a natural history amateur being swept into Civil War that first brought Powell into the orbit of my interest.

Last year I read William Darrah’s fine biography of Powell (Powell of the Colorado, 1951) and I am now savoring Wallace Stegner’s more literary account (Beyond the Hundredth Meridian:  John Wesley Powell and the Second Opening of the West, 1954).  I had been building a case for initiating Powell into my pantheon of heroes, but then on Saturday, while hiking on Great Falls’ Billy Goat Trail along the Maryland side of Potomac, I inducted him.  More on precisely why in a moment.

Powell led a life marked by restlessness, both physical and intellectual.  He bounced among three institutions of higher education, completing no degree.  He found employment as a teacher in country schools, teaching himself the math and science he needed.  His desire to learn paleontology and geology prompted a wonderful period of rambling in his early 20s.  His school teaching jobs gave him months of freedom during which he wandered – a walk-about for four months in Wisconsin, a row-boat trip down the Mississippi from the Falls of St. Anthony in Minneapolis to New Orleans, another boat trip from Pittsburgh to St. Louis down the Ohio.

The Civil War precluded any chance of settling down; Powell enlisted in 1861 and saw serious action in the western theater of war.  After the war ended, Powell taught geology at Illinois Wesleyan University and Illinois State Normal University, but he was shortly on the move again.  Indeed, he is perhaps known principally for the several expeditions of exploration he led to the western United States beginning in 1867, and particularly for the one in 1869 when he and a small band of men navigated down the Green River and then the Colorado, traversing the length of the Grand Canyon.  They were the first to do so; a journey of great danger met with great bravery.

Powell is pictured below (later in life), as is the river boat Emma Dean (his wife’s name) with its chair from which he piloted during a subsequent exploration of the Colorado.  The original boat Emma Dean was one of four used in the 1869 descent, but late in the expedition had to be abandoned.  [Both images are from the Library of Congress' collection.  The Powell image at this link, and the wonderful stereoview of the Emma Dean image at this link.  Stereoviews have appeared previously in this blog, most recently in a posting about the dinosaur Hadrosaurus.]

In the latter part of the 19th century, Powell assumed leadership positions in the growing federal scientific community, promoting an active federal role in science.  From 1881 to 1894, he directed the U.S. Geological Survey.  His deep interest in the ethnology of the Native American peoples he encountered during his western exploration culminated in his assumption of the directorship of the Smithsonian’s Bureau of Ethnology.

The Brief for Hero Status

What’s in the brief in favor of hero status?  Facing and besting the unknown challenges of the Colorado River in 1869 certainly figure prominently.  That a self-taught geologist could make signal contributions to physical geology, drawn from his analysis of the geology of Colorado Plateau Province, ranks up there.  In that regard, as Wallace Stegner wrote in his Powell biography,
Quite alone, his generalizations about earth movements (with his support of uniformitarianism when it was still widely disputed), about the character of rivers and the forms of earth sculpture and the laws that govern erosion, would more than justify his years of work in the West. (p. 155)
During his years in the Washington scientific community he endured the wrath of forces in Congress and corporate America (read:  the railroads) by speaking forcefully about the inability of much of the land of the west to support the kind of agricultural development in which those forces were invested.  That alone for me is almost enough to make the case for hero status.  Powell denied that “rain follows the plow,” the pseudo-science that undergirded the western development movement.  He countered with conservation, careful land management, and with . . . science.

His Civil War service certainly elevates his status.  Powell came in as a private and left as a lieutenant colonel.  He served as a military engineer, learning this science in the field as he had learned so much else.  He experienced many of the major battles of the West, including Shiloh and Vicksburg.

Oh, one other thing about Powell.  At Shiloh, he was shot in the right arm and Army surgeons amputated it above the elbow.

That loss of an arm is the key to Powell’s induction on Saturday into my pantheon of heroes while I hiked the Billy Goat Trail.  The trail follows the riverside perimeter of Bear Island, part of the Chesapeake & Ohio Canal National Historical Park.  Here is the Google Earth view of the general area.

View Larger Map

It well deserves the cautionary note struck by the Park Service on its map of hiking trails at Great Falls, Maryland.
Be prepared for the Billy Goat Trail, Section A.  It is a very Physically [capitalization by Park Service] demanding trail.  If you have doubts about your physical ability to climb over angled rocks and boulders, please consider one of the Park’s less strenuous trails.
Led by a retired geologist, the group of which I was a part was there for the area’s amazing and starkly visible geology (perhaps something on that in a later post).  At times, the Billy Goat Trail takes you on a path that lies between a rock face on one side and the steep drop on the other or it heads straight up the rocks.  The views across the gorge through which the Potomac flows are breathtaking, but so is the sheer drop just off the perch on which you walk or sit.

Let it be said that I came to this hike having deliberately ignored the Park Service’s warnings.  I had some doubts about my ability to handle the hike – heights are not my friends.  But, even worse, problems with the rotator cuff in my left shoulder limit what I can do with that arm.

Though I managed to survive, putting up with some pain and avoiding some precarious spots, I realized very early on that climbing cliffs and scaling rocks are not things for a one-armed man.

And yet there was John Wesley Powell during that 1869 expedition repeatedly climbing the cliffs that led up from the rivers in order to determine altitudes and study the geology.  Stegner noted that the members of his band had little patience for Powell’s scientific activities during the descent and his caution in navigating the rapids.  But,
in spite of his science, they had to admire him.  One-armed, he was as agile on the cliffs as any of them.  He had nerve, . . . .  (Stegner, Beyond the Hundredth Meridian, p.71)
Yet, the absent arm nearly spelled his death.  Here’s Stegner on one such episode:
Wanting to know as much as he could about the unexplored land back from the river, Powell took [George] Bradley and climbed up a steep, ledgy wall in blistering sun.  Somewhere on the cliff he made the mistake of jumping from one foothold to another, grabbing a projection of rock with his one hand.  Then found himself ‘rimmed,’ unable to go forward or back. . . .  Below his feet was a hundred-foot drop, a terrace, and then a longer drop.  If he let himself go he might fall clear to the river’s edge.  By now his legs were trembling, his strength beginning to waver.  As a desperation measure Bradley sat down on his ledge and yanked off his long drawers, which he lowered to Powell.  With nice timing, Powell let go the knob, and half falling away from the cliff, grabbed the dangling underwear.”  (p. 72)
Despite this close call (and thank God for long drawers), Powell’s cliff climbing continued for the duration of the 1869 expedition.  My little taste on Saturday of what he dealt with from the inception of the journey at Green River Crossing, Wyoming on May 24 until its end on August 30 was the final piece of evidence that sealed the case.  The man was a hero.

Wednesday, May 11, 2011

Single Point Perspectives

A comment by playwright Tony Kushner (Angels in America) gave me a vocabulary and a frame of reference for a phenomenon of my fossil hunts, or any such searches for that matter.

First, let me set a scene.

It’s an early May morning and I am on my hands and knees, intently scanning the gravel that has accumulated at a bend in the stream.  Small blossom petals, fallen from the trees overhead, have blackened and rolled into narrow pointed cones that lie amid the quartz pebbles.  I try to distinguish the decaying petals from the tiny fossil shark teeth with their black needle-like crowns that may lie hidden here.

For a moment, the most important aspect of my life, indeed, the world (sight and sound), lies right before me at this single spot in this stream bed which may or may not yield a fossil.

A sudden plop of something hitting the water breaks my concentration.  Certainly all the time I’ve been in the woods I’ve registered at some level of consciousness the noises of life around me.  Dominating is the intermittent raucous chatter of a leaf blower coming from the housing development hidden from sight by a hill and trees.  At those moments when the blower ceases, the air fills with the faint whir of traffic, the calls of birds from the black cherry and locusts high overhead, and the shuffling of squirrels on the hunt themselves in the leafy detritus beneath the mountain laurel and young dogwoods.

Clearly my search and I are just very, very small elements in a huge, complex living scene.  And, for nearly every other nearby living creature, my search for fossils is insignificant, meaningless, unknown – their lives continuing unaffected by my presence.

That is a fundamental incongruity of the search for fossils – how it takes me out into a location that offers vistas of woods, mountains, or the waters of rivers, bays, or oceans, but then I render that world into a single point perspective scene focused only on me and the ground at my feet.

Driving away from the fossil site that afternoon, I listened to Studio 360 where Kurt Andersen, host of the public radio show, interviewed playwright Tony Kushner about his new play, The Intelligent Homosexual's Guide to Capitalism and Socialism With a Key to the Scriptures.  Andersen noted that the play has scenes in which several characters on stage speak at once, their voices clashing, mingling, obscuring.  Though I have not seen the play, Andersen ran snippets of those scenes so I have a sense of what that’s like.  Indeed, in one scene, 11 characters speak simultaneously.  Andersen interpreted this as the playwright undercutting the presumption in a play that every word is precious.  Kushner’s response went deeper.  He noted that members of the audience have to decide what’s important because their attention cannot be everywhere.  This is art reflecting life.  He observed (this is my transcription of this part of the interview),
There’s something that Brecht says, that Renaissance painting with a single point perspective where all the lines guide the eye towards the baby, the Madonna and the child, and he compares that to Brueghel or Asian painting where you don’t know where to look, you’re not being told where to look, you kind of have to wander around in the world before you can find Icarus falling in the sea.  And that sense of freedom to roam around I think is an interesting experience.
The “freedom to roam around” may be an “interesting” or liberating or challenging aspect of the play or the Brueghel painting for outside observers (and I like the idea that most things are of equal weight and perhaps worthy of exploration and writing about).  But that’s not what particularly struck me.  Rather, I found myself thinking that the absence of a single point perspective for the viewer from afar is complemented with a unique single point perspective held by every character in the play or the painting.

What did poet and playwright Bertolt Brecht actually have to say about Brueghel?  In a collection of Brecht’s notes and essays is a small piece titled “Alienation Effects in the Narrative Pictures of the Elder Brueghel” (Brecht on Theatre:  The Development of an Aesthetic, edited and translated by John Willett, 1964).  In the interview, Kushner was referencing Brecht’s notes on The Fall of Icarus by Pieter Brueghel the Elder (~1525 – 1569) (I’m spelling his surname as Brecht did) which captured the tragedy of Icarus who crashed into the sea when he failed to heed his father Daedalus’ warning and flew with his wings of feathers and wax too close to the sun.  (The image below of the painting is from the WebMuseum, created by Nicolas Pioch and licensed under the terms of the Creative Commons Attribution-ShareAlike 3.0 License.)

A truly amazing painting.  The tragedy, the end of Icarus’ world, passes unnoticed.  As Icarus’ legs disappear beneath the waves (an almost comic touch), the world moves on, the plowman plows, the fisherman fishes, and the shepherd gazes contemplatively skyward (but certainly not in response to the vision of a man falling from the sky).  Only the fisherman appears to be facing where Icarus plunged into the water, but there seems no urgency to his actions which I think remain all about fishing.

Here’s Brecht on the painting:
In The Fall of Icarus the catastrophe breaks into the idyll in such a way that it is clearly set apart from it and valuable insights into the idyll can be gained.  He doesn’t allow the catastrophe to alter the idyll; the latter rather remains unaltered and survives undestroyed, merely disturbed.
. . . . Tiny scale of this legendary event (you have to hunt for the victim).  The characters turn their backs on the incident.  Lovely picture of the concentration needed for ploughing.  The man fishing in the right foreground, and his particular relationship to the water.  The setting of the sun, which many people find surprising, presumably means that the fall was a long one.  How otherwise can it be shown that Icarus flew too high?  Daedalus passed from sight long ago.  Contemporary Flemings in an ancient Mediterranean landscape.  Special beauty and gaiety of the landscape during the frightful event. (p. 157)
The fall into the sea, a disturbance, nothing more.  Disturbing thought, but, by virtue of our own consciousness, I think we have to make our lives a succession of single point perspectives (single points of perspective?), that’s how we relate to the generally uninterested world around us.  The fossil hunt seems a special case where we turn our back on the world and our awareness of the contrast between our narrowly focused perspective and the obliviousness of much of the rest of the world can be particularly acute.

Oh, and yes, (back to me, of course), on this day, I found a few fossils in this Cretaceous site (the two fossil teeth from sand tiger sharks pictured above are among them) where specimens from more than 65 million years ago turn up just often enough to keep a few of the committed believing we each have a reason to return, though the fossil gods don't care.
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