The Flaperon’s Path to Réunion

drifter-screengrabAs As I wrote back in September, Patrick De Deckker is an Australian scientist to whom the French authorities entrusted a 2.5-cm-long Lepas anatifera shell.  De Deckker has analyzed the shell to determine the ratio of magnesium to calcium within it. Because this depends on the temperature of the water in which the barnacle is growing, and the shell is laid down sequentially like the rings of a tree as it gets bigger, the barnacle can essentially serve as a record of the water temperature of the ocean it floated through. This raises the question: can this analysis tell us something about the route the flaperon traveled?

In August, De Deckker told an Australian journalist: “The start of the growth was around 24 degrees (Celsius) and then for quite some time, it ranged between 20 and 18 degrees (Celsius). And then it went up again to around 25 degrees.”

To me this suggested an obvious route of inquiry: all we had to do was sift through the Global Drifter Program for drifters that wound up in the vicinity of Réunion during the months of July or August of any given year (the flaperon washed up at the end of July, 2015) and see which of them experienced that kind of temperature profile.

I asked for volunteers to help sift through NASA or NOAA databases available online, but no one came forward. Fortunately, my brother-in-law John Swart, a database whiz, came to my rescue. He gave me a copy of Filemaker and showed me how to import data from NOAA’s Global Drifter Program.

Every day, four times a day, these drifters transmit their position and temperature via satellite to the nerds at NOAA. Using this location information we can plot how each one arrived in the vicinity of Réunion. In the Google Earth screengrab above you can see the path that each of 16 drifters took from the start of the calendar year to July/August (the data spans from 2000 to 2015). The upshot: many of the drifters started out fairly close to Réunion, and sort of swirled around. Some came from fairly far away, however–some from the northeast, others from the east or southeast (the direction of the 7th arc).

You can view the drifters’ movement by dropping this .kmz file into Google Earth.

So how did all these paths relate to temperature? With Mr Swart’s help I tabulated all the temperature data for the 16 drifters I examined. Here are the results for 12, as much as will fit in a Filemaker chart (click to expand):

reunion-drifter-temp-data

Not that, as time passes, the range of temperatures shrinks, as the drifters converge on the waters near Réunion. (If you have FileMaker you can look at the underlying data set here. CSV here. Excel here.)

I should point out that according to the world’s leading Lepas Anatifera expert, Cynthia Venn of Bloomsburg University, barnacles this size are probably only a couple months old, perhaps as much as four months if we want to be really conservative. So we should look for a U-shaped temperature pattern somewhere between day 90 and day 210.

The closest we see to this pattern would, I suppose, be drifter 71030 or 41337. But neither of these experienced water temperature lower than 21 degrees. (Of the four drifters that didn’t fit on the graph,  the coldest temperature experienced was 23 degrees.)

To my mind, this suggests that the flaperon may not have arrived at Réunion through a natural process of drift.

To be sure, there are other possible explanations for this apparent anomaly. We don’t really know, or instance, how accurate Dr De Deckker’s paleothermometry really is. And it may be that by statistical fluke the flaperon happened to wander off into cold water and back again.

But these findings emerge in the context of other hard-to-explain aspects of the recovered aircraft debris:

— As confirmed by French investigators, the flaperon somehow acquired a population of Lepas barnacles even though its natural tendency was to float high in the water

— The majority of the debris has been collected in a statistically unlikely way

— The majority of collected debris is uncharacteristically devoid of marine life

— On the pieces that do have marine life, it appears to be too small given the amount of time spent at sea.

Taken together, these incongruities raise significant doubts about the provenance of the MH370 debris recovered to date.

While the Australian authorities have bent over backwards to explain their analysis of the Inmarsat data and how it lead them to define the seabed search area, they have been completely silent on the topic of biofouling (except to say that it exists). I wonder if it is because, like the French investigators who were unable to reconcile how high the flaperon floated in the water, they are stumped by inconsistencies in their data.

Australian officials have stated that they will release a comprehensive report on their findings after the seabed search is finished. Given that the last ship, the Fugro Equator, has now started its final stretch at sea, and the last mission lasted about six weeks, the search will likely be wrapped up by the end of January. Hopefully we will have some answers soon after that.