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polarjacksw asked: With the arrival in Australia of Benjamin in the next days, is there any chance to see Fontaine Maru coming back to Hawaii in order to explore the PacX route to Japan ? Did you have some GPS information coming from the ghost Piccard Maru ?
Benjamin has almost arrived in Australia. Fontaine is back in the shop and has almost finished being refitted. Part of the reason to do PacX was to perform some experiments, and we’ve learned some interesting exotic metallurgy from Fontaine. We’ll get him back in the water as fast as we can. Piccard should follow shortly after.
The first of our 4 transpacific voyagers has made it to Australia. After a hectic final dash through the East Australia Current, Papa Mau was picked up November 19th (the white line on the map). It got far ahead of the other waveglider headed for Australia (Benjamin) when the other took some damage to it’s solar panel, so we had it detour (the red line) through Samoa and have a pit stop at a beach resort - our repair technicians get the best business trips.
On November 24th Fontaine Maru, one of the wavegliders bound for Japan, was picked up and is on its way back to Hawaii. It’s going to get some repairs done before heading off again. Our thanks to the captain and crew of the R/V Kilo Moana!
kazenori asked: Can you inform me of the ETA of the Piccard Maru and Fontaine Maru in Japan as well as the location they will be coming ashore. Thank you
Unknown. They’ve both had mechanical issues and are in need of some help :-( They both had some experimental modifications that hadn’t been tested on a long voyage.
polarjacksw asked: Is the unit of the wind speed in m/s or in knots (Nm/s) ? When comparing a dataset coming from ERDAP database (transmitted unit is in m/s) and the same dataset downloaded from SLAB database (unit is in knots), this is the same value... even with a ratoi of 1.852 !!! The user manual of AIRMAR PB200 uses knots and MPH.
It’s in knots: the unit specification from the old ERDDAP database was wrong. It’s accurate to about 1/10 of a knot.
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Three of the PacX gliders are about to cross the international dateline, or at least the +-180 degree line. As one reader pointed out (thanks Jacques!), given the way the dateline wiggles around, one has already made the transition. While crossing the dateline doesn’t have quite the historic ceremony of an equator crossing, it’ll still qualify the bots as, in the terms of the Navy, members of the Order of the Golden Dragon.
If you haven’t seen it before, the PacX status page at http://slab.liquidr.com/finishline/ has a good selection of trivia.
Yesterday morning (July 17th) Papa Mau crossed the equator. The software survived the sign change with (almost) no hiccups :-) Benjamin should be crossing in a couple of weeks. To get a quick dashboard on the gliders, look here.
Papa Mau and Benjamin are still traversing an area of dense chlorophyll A concentration. As previously mentioned, the increased chlorophyll A concentration is indicative of a dense ‘bloom’ of phytoplankton, microscopic oceanic plants that are the food source for krill and other miniscule marine invertebrates, which in turn form the dominant food source for much of the marine fauna. The mechanics of seasonal algal blooms are much more complex than an occasional patch of phytoplankton randomly spawning in favorable conditions. Phytoplankton exist year round in the ocean, migrating with the currents and growing more profusely in warmer waters. Nearer the equator, their presence is stronger and much more stable, as water temperatures are higher and fluctuate less. This is why our northern pair of PacX gliders are not discovering as much phytoplankton.
These tiny, marine flora persist most constantly near the equator, where water temperatures are both the warmest and most consistent. A key reason for this is due to the angle of incidence of solar rays, which warm equatorial waters much more efficiently than that at the poles.
In a positive feedback loop, the increase in phytoplankton in the water increases its ability to absorb sunlight, further warming the water and improving the growing conditions for these plants. As less sunlight reaches past the phytoplankton bloom, a thermal gradient is formed trapping the warm, biologically active mix at the surface. This is the reason for the strong temperature spike seen upon entering the bloom.
Carbon sequestration is a popular concern. It has been shown that 1 gram of marine chlorophyll sequesters roughly 4 grams of carbon per hour (Ryther and Yentsch, 1957). Much of the carbon humans pollute is absorbed by the oceans, and much of that is done by the marine plant community. When eaten, the carbon is transferred to the fish and so on up the food chain, before top predators sink to the bottom of the ocean for longer term storage. In this way, phytoplankton is key, not just to sustaining life in the oceans, but mitigating the pollution created by the burning of fossil fuels. The processes surrounding these tiny plants must be understood more thoroughly in order to preserve them in a world of shifting currents and changing ocean conditions.
Currently, phytoplankton distribution is most efficiently tracked by satellite (Yoder et al. 1993), as demonstrated by our previously-posted satellite image.
Although satellite tracking can give an estimate of the distribution of phytoplankton, and point to the densest regions, in situ data serves to broaden our understanding of the oceanic conditions in these areas. Imagine a fleet of 100 wave gliders perusing the phytoplankton rich equatorial waters, mapping in high detail ocean currents, water temperature, salinity profiles, pH and even low-atmosphere weather conditions. Better understanding the relationship between all of these variables will greatly help to inform models and predictive strategies we will need to understand how the ocean, and its life, will change in the face of a climate being transformed by humans. There is no replacement for boots-on-the-ground research.
All life processes have an effect on our planet’s shifting climate. The oceans are critical to life. Let’s start to understand them much more thoroughly.
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References
There’s a new facility for obtaining data from vehicles. It’s much simpler than ERDDAP: it doesn’t support all of the file formats that ERDDAP does, it only allows data to be retrieved as CSV files. But it understands streaming and authentication very well - two properties that make it operationally fit better with the way our business and the wavegliders operate. It’s pretty easy to use: you go to http://slab.liquidr.com/fetch and select a vehicle, an instrument, a start time, and an end time (optional), and a “reuse style” and the website generates a URL for you. If you just click on the URL, the selected data will be downloaded and opened in whatever application you have set as your default for opening .csv files (OpenOffice, Numbers, Matlab, GNUPlot or Excel are the usual targets).
This URL is really useful when you’re doing scripting: you can use the URL to read the data from within your own application. In a unix shell script you’d probably use curl, in java you’d use new URL(…).openstream(). The “reuse style” option on the URL generation page becomes important when the URL is being used for scripting. It determines how the URL behaves when it is used more than once. The most commonly useful option is to have each use fetch only the new data.
It has all data from all vehicles. It should all be clean & correct… There is an unresolved question about dissolved oxygen calibration, and there are occasional GPS issues, but otherwise it should all be good.
To access the PacX data, use the login id “anon” and password “anon”.