Archive for June 30th, 2011

Keeping an eye both above and below

Thursday, June 30th, 2011

Hey all,

Well we are still chugging along, and making good time at that!  Yesterday afternoon, Challenger 1 was given a new waypoint back to the south east, and now we are heading almost directly south at an astonishing 1.35 km/hr (which is excellent for a glider) and have gone about 24.5 km since yesterdays afternoon surfacing.

There has been recent discussion about the currents that the glider is recording.  It seems that no matter which way we are moving, we are recording currents that are going about 90 degrees to the right, which haven't always correlated with what the Hycom model is telling us, and is also pretty suspicious in itself.  Within the next couple of days, we will begin flying with a program called current correction set on to try and correct for what the glider thinks the currents are doing and see if that makes any changes to our heading.

Next, we continued looking to the depths to make sure we stay a safe distance from the bottom.  Today I overlayed the bathymetry map from geomapapp onto google earth so we could see it along with the hycom currents and current glider position.  The cross section I took follows the path the glider would be drifting if we were continuing to follow the current and even in this scenario, the shallowest water is still about 1300m.  So we should be fine for the time being if we continue to dive to 1000m depths.

Shannon Harrison and Dave Kaminsky who have both been involved with the COOL room for many years also contributed to the path planning this morning; thus increasing our global collaboration to include our fellow Rutgers students currently interning all the way over in Perth, Australia at the University of Western Australia where they are helping with research in the Oceans Institute in conjunction with the Australian National Facility for Ocean Gliders and the Integrated Marine Observing System.  They pointed out that there are two general directions of the currents which they depicted with the two blue arrows, the red line dividing the two.  Both having experience in piloting gliders, they advised us to continue looking at the movement of the eddies to see how they progress now so we may plan for when we reach the areas with the most movement.

Another thing we must worry about, is the intensity and direction of the eddies changing largely unpredictably due to storms.  Due to the kinetic energy of the wind, the eddies may grow in both size and intensity in the presence of a storms.  And just our luck, Antonio pointed out today that there is a massive storm system headed our way!  To minimize the storms interference, we may take a look at our operational depth and make sure we are not rising up into waters that may be disruptive until we need to surface.  We will also need to keep an eye on our current models as the storm may cause eddies to change before the model has a chance to update.  This may lead to some discrepancies along the way.

Lastly I (Nilsen) would just like to apologize to our dear friends Antonio, The University of Las Palmas at Gran Canaria, and PLOCAN for any confusion I may have caused.  I accidentally gave Antonio's work credit to PLOCAN in two of my previous posts, when his official affiliation is actually with U. Las Palmas GC.  However, U. Las Palmas GC does collaborate quite regularly with PLOCAN.  So again guys my greatest apologies!

-Nilsen & Oliver