Last updated: Saturday 16th December 2017
The James Clark Ross has now moved further north and out of Antarctic waters. This evening CTD 11 is on the way back to the surface from a depth of almost 4,000m.
Once the CTD is back on board and secured to the deck, the scientists are allowed access to the water bottles and can start collecting the water samples that they required. Here the water is initially being used to flush out the flask before the sample is taken. A few simple measurements are taken at this point. For this particular sample a number of chemicals are then added to the water, which 'fixes' the sample and stops any contamiation.
I have recently been told that the JCR has deployed 117 APEX or ARGO floats in the past ten years, plus a number for foreign institutes. Most of these floats are small cylindrical instruments that will sink to about 1,000m and drift for a period collecting data. They will the surface to transmit the data back to the scientists before repeating the process. Some are still in operation after many years (they should last about five years but some have been working after ten). This APEX float is of a different design and rated to work at a depth of 6,000m and four will be deployed in the coming days. This float has been named Marlon, after one of the science team on board the JCR just now.
Once launched the float, which admittedly sinks, will sink to a depth of 25m. This will then kick start the process and it should then surface and run a number of checks, including sending a communication, before starting its scheduled programme, which will see it floating at depth and then surfacing to report back.
Sadly it is unlikely that anyone will ever see these again as they will eventually fail and more than likely sink. From time to time they have been washed up on far shores.
Noon Position Report Saturday 16th December 2017
|Latitude:||58° 31.60 S|
|Longitude:||056° 08.89 W|
|Bearing:||123 °T, 591 Nm from Punta Arenas|
|Total Distance Travelled:||2776|
|Total Steam Time:||301.5|
|Total Average Speed:||9.2|
|Wind:||Direction ESE, Force 3|
|Air Temp: 1.3 °C||Sea Temp: 2.5 °C|
|Pressure: 976.3||Tendency (3hrs): Rising|
Previous updates from the current trip.
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