Assessing a collapse

One of the coolest things about science is the cross-fertilization that happens between disciplines.

I'm always impressed when I see examples of this, and my reaction is usually, "How did you even think of doing that?"  It is, at its core, a highly creative process.  The best science involves looking at a problem from a different angle, drawing in data or methods from other disciplines, and putting the whole thing together in such a way that the answer is clear.  (Or at least, a piece of it is clearer than it was before.)  As Hungarian biochemist Albert von Szent-Györgyi put it, "Discovery consists of seeing what everyone has seen, and thinking what no one has thought."

The creative aspect of science struck me while I was reading an article yesterday in Ars Technica about a some new research into a historical puzzle: the sudden collapse of the Shang Dynasty in China, about three thousand years ago.  The Shang were in power for nearly six centuries -- a pretty long time for a single dynastic regime -- and had made some significant accomplishments, the most notable of which were the first recorded writing system for Chinese, and amazing advances in pottery making and bronze casting.  Then -- over a very short period, perhaps only a few years -- Shang rule imploded.  A rival group called the Zhou took advantage of the chaos to defeat the Shang in a bloody battle, then scattered the remaining Shang supporters throughout the land to assure they'd never be able to rise again.

Now, researchers at Nanjing University, led by meteorologist Ke Ding, have drawn on a variety of disparate fields -- meteorology, climatology, geology, archaeology, paleontology, and analysis of extant historical records -- to try to create a complete picture of the causes behind the Shang Dynasty's sudden demise.

Their conclusion: the collapse of the Shang was the consequence of a long line of dominoes that started with a series of prolonged and powerful El Niño events, thousands of kilometers away.

Paleontologists analyzing fossil remains in strata off the coast of Peru dating to around 1000 B.C.E. note a shift from cold-water species to those that favor warmer water.  The fact that there wasn't an oscillation back and forth, but a replacement by warm-water species that lasted perhaps a century, suggests that rather than the usual pendulum swing of El Niño/La Niña conditions -- the former causing a warmup of the surface waters off the west coast of South America, the latter a corresponding cooldown -- in the years before the Shang collapse, the climate seems to have switched over to a semi-permanent El Niño.  What would be the outcome of such a shift in the ENSO (El Niño Southern Oscillation)?  This is where the meteorologists and climatologists took over; they estimated the degree of warmup, and let their computer models predict what effects that would have.

One thing that popped out of the models was a drastic increase in the strength of Pacific typhoons, and a significant change in their paths.  The warmup shifted wind patterns, tracking large storms away from Australia (thus the droughts and wildfires in Australia and Indonesia that usually accompany El Niño years), and northward into China.  Typhoons, though, usually fizzle once they cross over from ocean to land; and the capital of the late Shang Dynasty was Zhaoge, in Henan Province, far away from the coast.  So how would typhoons have affected an inland city so drastically?

But the models showed that the altered wind direction didn't just shove storms toward China, it also fed warm, moist air inland -- atmospheric rivers.  These air currents flow until they meet a mountain range, and the humid air masses experience adiabatic cooling as they rise in elevation, causing them to dump their moisture as rain or snow on the windward sides of mountains.

In other words, the rain shadow effect.  The outcome; suddenly northern and central China were way wetter than they had been.

Now, enter the archaeologists.  One of the most common items in Shang-age archaeological sites are oracle bones -- usually the scapulae of ox, horses, or deer that are thrown into a fire, and the resulting cracks and scorch marks read by a shaman.  But fortunately for us, the shamans -- recall the Shang's development of the first Chinese writing system -- also recorded on the oracle bones what questions had been asked, and what the shaman's assessment of the results had been (i.e., the answer to the question).

And in the last fifty years of the Shang Dynasty, just about all of the oracle bones have to do with the weather.  A lot of them basically ask, "When the hell is it going to stop raining?"

A Shang Dynasty oracle bone [Image licensed under the Creative Commons Orakelknochen, CC BY-SA 3.0]

At the same time as this, the archaeologists also note the abandonment of village sites near riverbanks, an increase in burial of sites under riverine sediments, and the relocation of towns onto higher ground.

What Ke Ding and his colleagues concluded is that the Shang were weakened by years of floods, probably accompanied by poor harvests and resulting famine.  This set the stage for the Zhou rebellion, and the destruction of a dynasty that had ruled China for six centuries.

Now, here's the kicker.  The researchers caution that we're seeing a similar pattern today -- anthropogenic global warming is increasing oceanic surface temperatures, and the Pacific Ocean is seeing extended and more powerful El Niño events.  As Mark Twain observed, "History doesn't repeat, but it often rhymes."

Oh, except that noted climate scientist Donald Trump has evaluated the available data, and decided that global warming is a hoax, and the climatologists are big fat poopyheads.  So there's that.

Anyhow, it's a fascinating and elegant piece of research, and shows how creative the scientific enterprise can be.  Collaboration is the heart of discovery, and here we have an entire team of experts from disparate fields pitching in together to solve a historical puzzle.  One that, despite Trump's pronouncements, we had damn well better pay attention to today.

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We're in for a spell of weather...

Why is it that some people will believe anyone's pronouncements on anything, as long as said person is not a scientist?

I and others have ranted repeatedly about a large slice the public's dismissal of climate science and evolutionary biology.  And the anti-science stance of each of those, I know, comes from a different source; the petroleum lobby's power over the political system in the first place, and religion in the second.  But this general distrust of anything scientific runs deeper than that, touching on topics where there is no obvious motive for disbelief, where people for some reason will accept folksy tale-telling over evidence-based, data-driven research.

And that makes no sense to me at all.

As an example of this, let's consider The Old Farmer's Almanac, which just came out with its predictions for the winter last week.  And based on their methodology, which as far as I can tell involves voodoo and rain dances, we're going to have a wicked snowy winter.

"The snowiest periods in the Pacific Northwest will be in mid-December, early to mid-January and mid- to late February," the Almanac says, which at least has a better chance of being correct than their predicting a blizzard in, say, July.

But the fact is, no scientist takes what the Almanac has to say seriously, because their weather forecasting isn't science. According to an article in Consumer Reports, the Almanac bases its predictions on "a secret mathematical formula using the position of the planets, tidal action of the moon and sunspots" that is kept in a black tin box in Dublin, New Hampshire.

Because that's gonna be reliable.

And how accurate is it, anyway?  Skeptical blogger Steven Novella found one place where someone actually tested the Almanac's predictions, and guess what happened?

In the October 1981 issue of Weatherwise, pages 212-215, John E. Walsh and David Allen performed a check on the accuracy of 60 monthly forecasts of temperature and precipitation from The Old Farmer’s Almanac at 32 stations in the U.S.  They found that 50.7 percent of the monthly temperature forecasts and 51.9 percent of the precipitation forecasts verified with the correct sign.  These may be compared with the 50 percent success rate expected by chance.

This is my "shocked face."

But what pissed me off the most about this year's predictions was an article from KOMO News Online called, "Who to Believe?  Snowy Farmer's Almanac?  Or NOAA's Warm El-Niñoey Blob?" written by, of all people, a trained meteorologist who therefore should know better.  And while author Seth Sistek concludes that we should probably trust NOAA, which has forecasted a warmer-than-average winter for the northern United States because of a blob of anomalously warm seawater parked off the Pacific Coast of North America, even the fact that he asks the question gives unwarranted legitimacy to what honestly is a bunch of hocus-pocus.

[image courtesy of NOAA]

"[I]n the battle between Blob and book," Sistek writes, "I'd have to lean toward the Blob in agreeing with the supercomputers that it'll be a warmer winter."

Which, as endorsements go, is not exactly knocking my socks off.  What's next?  Asking the astrologers to draw up zodiac charts to predict solar flares?

Okay, I'm coming off as pretty harsh toward The Old Farmer's Almanac, I realize.  But the problem is, there's already a tendency in this country for people to buy pseudoscience over science, to distrust researchers, to look at scientists as ivory-tower nerds who are disconnected with practical reality.  We definitely don't need anything to push us further in that direction, even if it is "all in fun." To quote Novella again:

I hear many people quoting one almanac or the other about what kind of winter we are in for. They don’t seem to realize that the almanacs are using 200 year old pseudoscientific methods that have never been validated.  Despite the coy marketing of these predictions, many people take them as legitimate... 

It seems that the public did not want the scientific information – they wanted the predictions made by mysterious methods.  I can understand, for marketing reasons, why future editors of the almanac would not consider dropping the predictions.  But here is a recommendation – why not get rid of the two century old dubious methods and replace them with the climate forecasts made by the National Weather Service?

Because, apparently, folksy prognostications still carry more weight than actual science with a large sector of the American public.

Look, I know that meteorology as a science still has a long way to go.  Weather and climate are vastly complex systems, extremely sensitive to initial conditions, and long-range forecasting is still fraught with inaccuracies.  Even the most highly-trained meteorologists, using the latest computer models and our best understanding of how the science works, still get it wrong sometimes.

But damn it all, it's still better than magic formulas in black tin boxes in Dublin, New Hampshire.