Punchline:
Besides his bad science, Winchester suggests that potential survivors should give up hope, and this is not true [see my prior blog]:
http://paleotsunami.blogspot.com/2011/03/more-than-half-full-survivors.html
I surely hope that Mr. Winchester is not claiming any scientific background (he has an undergraduate geology degree from Ozford) in the case of this essay, in which he badly misrepresents scientific and cultural knowledge, to the point of potential harm in future events, and insult to Japanese victims and survivors.
http://www.newsweek.com/2011/03/13/the-scariest-earthquake-is-yet-to-come.html
I only hesitate to write this because it will bring further attention to this awful essay, which in turn might cause Mr. Winchester sell more books. I am speaking only to the tsunami, and related geological comments; for more about the seismicity issues, see:
http://www.facebook.com/notes/christie-rowe/i-write-angry-note-to-simon-winchester-again/10150219434088332
Here are some excerpts from the Winchester’s essay (his quotes are in italics, with points of particular contention in red), with my comments (particular rebuttals in blue), especially with reference to the tsunami:
I. …all geological events are sudden, and all are unexpected if not necessarily entirely unanticipated….
Jody remark: The first phrase is a tautology, completely depending on the definition of “geological event.” As geologists, we recognize many “events” in the geological record that are perhaps “sudden” on a geological time scale, but not on a human time scale. If you want to sell more of your books, then this would be a good description of a “geological event.” Moreover, these events are not unexpected, they just may be hard to predict, though Winchester later contradicts himself by predicting the San Andreas fault will be the next to go (the most egregious part of the essay, see Christie Rowe’s link). A counter-example of something that has become predictable in many cases would be volcanic eruptions, though, like the 2011 Tohoku events, the scale can be beyond what was formally anticipated.
II. ….At first, the shock was merely a much stronger and longer version of the temblors to which most Japanese are well accustomed. There came a stunned silence, as there always does. But then, the difference: a few minutes later a low rumble from the east, and in a horrifying replay of the Indian Ocean tragedy of just some six years before, the imagery of which is still hauntingly in all the world’s mind, the coastal waters off the northern Honshu vanished, sucked mysteriously out to sea….
Jody remark: it was not mysterious at all to the Japanese, they are well educated for what to expect after a large earthquake, if they are on the coast. All the tsunami warnings went off, many people who had the opportunity escaped. It’s only true that this tsunami was larger than formally planned for.
III. ….The rumbling continued, people then began to spy a ragged white line on the horizon, and, with unimaginable ferocity, the line became visible as a wall of waves sweeping back inshore at immense speed and at great height. Just seconds later and these Pacific Ocean waters hit the Japanese seawalls, surmounted them with careless ease, and began to claw across the land beyond in what would become a dispassionate and detached orgy of utter destruction….
Jody remark: Well, I guess it’s fair to say that tsunamis are “dispassionate and detached.” However, by the time the tsunami approached the shore, it was not moving at immense speed (see below), and the heights until it came onshore (and in that case particularly in steep regions) are also not great. It took minutes to tens of minutes for these waves to hit the seawalls. The destruction was indeed terrible, but many reinforced concrete structures survived.
IV. ….But in this corner of northeast Japan, with its wide plains of rice meadows and ideal factory sites and conveniently flat airport locations, there may well be a great deal of inland—but there is almost no uphill….
Jody remark: Winchester has decided to focus only on the Sendai plain, whereas the majority of the affected region is not at all flat. And then his problem is, that by focusing on Sendai, the following points he makes are even more mistaken.
V. The most egregious, partly because it causes potential survivors to give up hope:
….And so the reality is this: if a monstrous wave is chasing you inland at the speed of a jetliner, and if the flat topography all around denies you any chance of sprinting to a hilltop to try to escape its wrath, then you can make no mistake—it will catch you, it will drown you, and its forces will pulverize you out of all recognition as a thing of utter insignificance, which of course, to a tsunami, all men and women and their creations necessarily must be….
Jody remark: Completely bad science about tsunami speed, and anyone who watched the tsunami cross the Sendai plain, with any experience in watching tsunami videos, would marvel at how slow and almost stately it was, albeit still terrifying. Reinforced concrete along the shore and inland (such as the airport building) survived, and many people survived here by moving quickly away from the shoreline as soon as shaking stopped. They were not ignorant of tsunami threat. And, as anyone who would care to look up “tsunami” in any reasonable reference knows, they move at the speed dependent on the square root of water depth (see footnote), hence the tsunami as it approached Sendai already was moving much more slowly than a jetliner (“jetliner” is the speed over the deep ocean, several kms deep; see footnote) and was moving even more slowly as it cross the Sendai plain. I guess on the Sendai plain you could say it was the speed of a jetliner as it taxis… not trivial to outrun, but there was advance time.
Bottom line: I agree with Mr. Winchester that the Earth can throw punches beyond the scale of local human survival, though except for asteroid impacts, these remain local events on a global scale and have not brought an end to the human species, which would be a real “geological event.”
Besides his bad science, though, Winchester suggests that potential survivors should give up hope, and this is not true [see my prior blog]:
http://paleotsunami.blogspot.com/2011/03/more-than-half-full-survivors.html
Footnote:
The speeds as the tsunami crossed the plain are not trivial, but given that people had natural and human warning systems, and that they had 10s of minutes to start their escape, most would have made it.
Speed of a tsunami –example of Sendai plain
| Where? | Water depth | Speed | Speed |
| meters | km/hr | mi/hr |
| over the deep ocean | 4000 | 713 | 442 |
| at the edge of the shelf | 200 | 159 | 99 |
| "as it approaches" | 50 | 80 | 49 |
| beginning to be visible from ground level | 10 | 36 | 22 |
| at Sendai airport, max | 5.7 | 27 | 17 |
| crossing the plain, typical | 2 | 16 | 10 |
Tsunami wave speed = √(gh) --this is the basic “shallow water wave equation”
= [square root of (g times h), where g is gravitational acceleration, it’s ~9.8 m/sec/sec on Earth’s surface; and h is water depth]
These speeds are calculated without consideration of viscosity, which was higher than water on the Sendai plain, because of mud and vegetation, and this would cause a lower speed.
