Tag: Nilsen Strandskov (Page 8 of 11)

Hey all,

Well we still seem to be caught in the strong northerly currents I spoke of last nigh which have now over powered Challenger and have started pushing him to the North East.

 

To try and combat these currents, we moved the way point a bit further east and set the buoyancy drive to full.  Hopefully this will give us enough kick to try and break free of these strong currents and begin making progress to the south when we reach the edge of this eddy.

Nilsen & Antonio

Now although Einstein was talking about the space-time continuum, this holds true for Challenger and his current situation.

Jumping back a few days, we had changed our way point to try and keep ourselves from drifting too far to the east.  However, we went right into a wall…

We ended up on the northern western side of a strong warm eddy that had currents in our vicinity that reached up to .3m/s moving north east.  As you can see in the picture above, we have made very little progress vertically as Challenger just does not have the horse power to plow through currents of that magnitude.

Shown in the figure above of the North/South components of the currents, we are still in the midst of some very strong currents, so early this afternoon we changed the way point back to the east.  We chose to put it at 22W so that we follow the northern side of the warm eddy around to the east rather than continue to make minimal progress (the curve being the shortest distance between where we are and where we want to be).

The changed way point resulted in Challenger being launched to the east as it no longer was trying to fly nose first into the North current.

Now the projected path for Challenger will be somewhere along the lines of following the eddy along to the east before swinging back west towards the Azores where we may conduct a rendezvous off the coast of Terciera.

However we must ‘watch our step’ as at the bottom of this eddy we get within range of a number of seamounts where the bathymetry becomes less than 1000m.  When we reach this area we will have to adjust our dive angle to avoid running into the sea floor.  Once we are past the area with the sea mounts, depending on our location due to drifting, we will discuss whether or not we could get back to Terciera or if Soa Miguel would be a better option.

We will post again soon with more updates!

 

Nilsen & Antonio

Hey All,

Over the past week, Challenger has really earned his spot in the Robot Hall of Fame, as he has gone through a number of obstacles and came out the other side unscathed.

Sadly it has been a very busy week with students coming back to campus, and I haven’t been able to give these achievements the coverage they deserve, so lets take a few steps back to the first week of September and see if I can hit all of the points.

September 6th, 2011: Birth of an Eddy

Back as Challenger was crossing the 2,000 km mile stone and entering the VVIG club (very very important glider club), we also witnessed what we believe to be something truly remarkable: the birth of a solar marine system!

 

As the remnants of Hurricane Irene blew through the vicinity of Challenger, we saw a strong inertial oscillation of the currents as it passed.  As seen in Figure 2, looking at the sea surface height anomaly  we can see how the end of a swirling arm from the edge of the Gulf Stream was in the process of breaking off, resulting in the presence of a warm core eddy surrounded by a number of smaller cold core eddies: thus the birth of a warm core solar marine system!

September 7th & 8th, 2011: THE WALL

Figure 3 Storm Surge

By September 7th, Challenger was bravely fighting its way through what has been one of its most enduring oppositions to date.  He was in the midst of a series of storms the literally arced from the eastern sea board of the United States, to the Norther shores of Europe and the United Kingdom.  This succession brought about some of the strongest inertial oscillations of the entire mission, where as you can see from the side image, the currents made almost a 180° while nearly doubling in intensity within two surfacings (~15 hours).  But we our proud to say Challenger is a tough little robot with a lot of spunk and is truly the definition of the phrase “-do not wait until the end of the storm…learn to walk in the rain”

click here to watch a gif of the storm progress over Challenger.

September 9th, 2011: Crossing the Freeway

After a few days of pounding waves, gale force winds, and unpredictable currents, Challenger continued on its crossing of the freeway of storms.  As we crossed the band, the brave glider began drifting a bit out to the west with the overall path of the currents, but was other wise unscathed.  As Scott said, every glider has a personality.  After the continuing performance by Challenger, we think his personality is along the lines of a cowboy from the wild west or a 4×4 steadily crossing treacherous terrain.

In the afternoon, after analyzing the southwestern drift we decided to start considering a new way point for the near future.

September 11th, 2011: Katia

Over the past 84 days, there has been very few instances where we were scared for the well being of Challenger, this being one of them.. As Hurricane Katia left the eastern seaboard of the United States, she then reared her ugly head in the direction of Challenger.  Now he has been through quite a few storms (33 as of this evening), but Katia brought conditions we had not yet experienced.

Katia not only brought strong winds, shifting currents, and a ton of rain, but also produced massive waves 9m (~27 feet) high and sent them right in Challengers direction.  Now as durable as Challenger has proven to be, being tossed from the crest of a 30 ft wave to the trough can really do some damage, but in the name of science and bravery Challenger fought through these perilous conditions and made it out the other side.

September 12, 2011: Cross Roads

Monday morning, after we were free of the intensity we had seen a day earlier, I had noticed we were really continuing on a path in a southwesterly direction.  Especially now with the Azores less than 900km away, I thought that we should move the way point east a bit.

By doing so, we could keep ourselves going in a straight line more in the direction of the Eastern side of the Azores instead of taking the scenic rout.

Also Challenger reached yet another mile stone on his journey as he now has the East coast of the United States of America to his west.  He is now even with the Northern tip of Maine.

September 13, 2011: Some Beautiful Imagery

After the change of way point, Challenger continued on its way, now gradually cutting back a bit to the east (meaning the change of way point was a success!).  We also noticed how much of an effect Katie had on the waters we are exploring.  This can be seen below in the drop in surface temperature and salinity in the two profiles.

As we can see, at Sept. 11th when Katia hit, there was a large mixing event in both Salinity and Temperature which depicts where the storm came through feeding off of the oceans heat and causing the waters to mix.

September 14th, 2011: The Saga Continues

Now that we are all caught up on the many adventures Challenger has bested over the past week, we can look into what the ocean is doing now and return to piloting the glider.

Figure 8. Sea Surface Height with Currents for 9/14

Above, we can see that we are fighting the Northwestern currents from the east side of a cold eddy.  Even with the head current and being in the midst of the 33rd storm, Challenger continues to make southern progress on its way back home to the Canary Islands.

Figure 9. Meteorological Imagery for 9/15

Also interesting to watch over the next day or so is the Chlorophyll satellite imagery.  With the amount of mixing the waters near Challenger has seen over the past few days, we are due for a large phytoplankton bloom.  Already we can see increased activity in our area.

Finally, it looks like the way point is good for now as Challenger continues to make gradual eastern progress on its way towards the Eastern side of the Azores.  Soon we will have a concrete plan on where we will sail and from there we may make further adjustments.

It has been a long and painful week for Challenger, but after what he’s been though I wouldn’t doubt this brave robot will taste the victory champagne in a few months on the shores of the Canary Islands.

As always, Force, Wind, Sea and Honor

 

Nilsen & Antonio

Hey All!

I just wanted to give everyone a quick update before the end of the day.

First off, it is official, Challenger has now flown over 2,000 km!  As of the last surfacing, he had flown 2,000.48 meaning we are just short of being half way to the end zone!

We are now just about 900km from the Azores, and about another 1,100 km from our goal of the Canary Islands.

Zooming in, the slight change of way point we made this past weekend is effecting our flight very well.  It prevented us from drifting to the east which we were trying to avoid.  however, it looks like over the past few hours the currents have shifted.

Looking at the sea surface height image above from Antonio and ULPGC, it looks like we are teetering on the boarder of a small cold eddy (directly to our north) and a warm eddy to our south, which may explain the shift in currents.  We expect to see the effects of the warm eddy to our south within the next surfacing or so which will then drag us back east.

The North South components map confirms our prediction as well if you look at the area we are in which is white meaning there is more of a northern flow (cold eddy) relative to our south east which has more of a southern flow (warm eddy).

Another interesting point, the sst looks quite groovy from today with a very interesting  tie die pattern

From here we can see that we are still on the edge of a warm band where there are a number of eddies breaking off as the warm and cold waters clash thus causing a quite extensive eddy field on along the boarder.

Finally, it looks like Challenger is directly below a few bands of rain carried by the Jet Stream, possibly adding to the changing of the currents.

As always our friends, Force, Wind, Sea and Honor…

 

Nilsen & Antonio

Greetings all!

As we are getting ready for bed on the evening before Labor Day, Challenger is once again setting records.

First off, Challenger is now is now well beyond the southern tip of the British Ilses, and is deep into French territory.  Second, when we wake tomorrow, Challenger will have officially have traveled over 2000km! Finally, the results are in from the buoyancy test from this past week, and the results are truly remarkable.  Our brave little droid went .93 m/s, blowing the previous record of .61m/s well out of the water!

Today our discussion turned to the changing of Challenger’s way point.  Antonio sent out some great figures showing that there was a strong flux moving to the east that we entered as of this morning.

 

This first figure is of the currents Challenger is facing at the surface showing a flow to the south east. What we want to do is to keep to the west of the red mass of velocity to our south.  Once we make it past there, we will most likely move the way point back to the east.

At about 500m depth, the currents are now moving up against us going to the North.

Finally at 1000m depth, the currents are moving to the East-southeast.  To combat these currents and keep Challenger moving towards more favorable currents, we moved the way point just a bit to the west (from 2455W to 2655 W) to keep the nose pointed to the south until we get out of the Eastern flux.

I also just would like to point out the amazing imagery we have from the sea surface salinity courtesy of Antonio and ULPGC.  Challenger is moving deeper into the outer most arms of the Gulf Stream, and looking at the Salinity it is very clear how the waters are mixing as the warm, salty water of the North Atlantic clashes with the colder, fresher water.

Finally, there has been some discussion about possibly running another experiment with setting the buoyancy drive to full to increase both vertical and horizontal velocity.  As mind blowing as the results were, we must be careful with this new strategy of taking advantage of the favorable currents.  First off, although it broke our previous speed record by 50%, it was also consumed quite a bit of energy so that must be monitored.  Also we must be absolutely sure of what the currents are doing in order for it to be most effective.  We have seen recently (especially with it being storm season) that the currents can change quite abruptly, and if we get caught in a change up that could result in the adjustment being useless.  Keeping this in mind, we may use use our new trump card when the currents are most favorable and only sparingly in short stints.

I hope everyone enjoys the remainder of the holiday weekend!

Nilsen & Antonio

 

Hey All!

So as the remains of Irene begin to reign down on the area Challenger is currently making its way trough, our team agreed to run a few tests to see what this glider is truly capable of.

Thus far in this mission, we have been operating using only about half of our available buoyancy drive.  So while we were in favorable currents, we ran a test mission to see what effects changing the dive angle and other aspects such as battery position would have on our flight patterns.  These test missions were conducted about mid day yesterday, and after some plotting and analysis, we will better understand what changes occurred.

One noticeable effect, which we discussed multiple times before going ahead with the test was the effect on battery.  If we have more parts moving in order to increase speed, we use more power, draining the battery faster. The plot of battery usage with estimated end date made by Ruben reflects how the effect on the battery from the change in flight pattern from the test.

we can see how the date of when the batteries will be used up dropped back down to end of January from a few days into February.  However, after we analyze the data from these tests, we will be able to see more clearly the benefits of flying this more aggressive style.

But before we can fly some more test missions, it looks like we will have to find our way out of a new eddy system.

Challenger seems to have been caught by the strong westerly currents from the southern side of the eddy we were currently in the midst of.  So depending on where we surface after this recent segment, it looks like we will end up fighting the northern currents of the west side of the eddy to our south until we can catch the warm eddy that is to our south west which will hopefully push us on our way south to the Canary Islands!

Finally we will leave you with this incredible imagery courtesy of NASA of Hurricane Irene’s progress through the carribbean and up the eastern seaboard of the US.

 

As always we will keep everyone posted

Force, Sea, Wind & Honor!

 

Nilsen & Antonio

Hey all!

I would like to apologize I was writing this Friday but then was distracted by Irene and headed home for the storm but I am finally getting a post back up.  But our prayers are out there for everyone effected by the storm and it’s aftermath.

Spectacles such as this shot of Rt 18 North and South bound with New Brunswick NJ, on the left and the Raritan River over the barrier to the right were scene all along the eastern seaboard of the United States from the Carolina’s all the way up through Vermont, to where Tropical Storm Irene now sits up along the eastern shore of Canada.

Unfortunately, as Challenger is in the midst of storms 25 & 26, it may feel Irene’s wrath as well if the Jet Stream carries her that way.

But back to looking at Challenger’s progress… As of yesterday morning, Challenger has officially made it south of the southern tip of England!

Over the past week we have made some great progress as we have gone from one eddy to the next, and with the way point changed to just about above the Azores, we can keep on our path to the south.  Looking at the sea surface height data from U. Las Palmas, we have been riding the eastern side of a number of warm eddies, and if we catch the SW currents we predict, we should cover quite a bit of lounge.

The eddies also are picked up quite well by the sea surface temperature from Las Palmas shown below

The picture above shows the sst that very clearly outlines the gradient caused by the gulf stream that we are beginning to breach.

Taking an even closer look with the 72 hour satellite imagery from Las Palmas, we can see an arm from the gulf stream swirling up and around in the pattern of a warm core eddy that also follows the currents forecast.

Finally, last week we made a few adjustments to the flight characteristics of Challenger, including making the dive angle less extreme.  This caused two things: 1st was that it caused each dive to take longer, but 2nd it proved to be very energy efficient.  A plot of energy consumption predicting how long our batteries will last is below.

Stay tuned for future updates!

Nilsen & Antonio

Hey All!

 

As Challenger 1 continues to work its way south along the eastern side of the second large warm eddy of the solar system and battle its way through our 22nd storm, we continue to make good progress as we are now half way to the Azores!!!  The two images above are of Sea Surface Height showing our path along the eastern side of a large eddy.  Keeping this pace, we could reach the Azores by the 2nd week in October and so if Challenger has begun feeling any effects from biological growth, we will be able to provide aid.

These storms however are intensifying as we get later in the year.  As the summer months warm the North Atlantic, the strong storms we see along the Eastern Sea Board of the U.S. gain strength as they then are carried by the Jet Stream right to us!

Speaking of the warming seas, lets look at an interesting point in the temperature data from the North Atlantic.

The first image is surface temperatures while the second image is of temperature at depths of 300m.  The second image shows how deep the effects of some of the larger eddies can be seen.

Similarly, looking at the temperature profiles from Challenger since deployment, we can see the thermocline grow deeper as we passed through the wall of warm core eddies along our journey.

Finally, we see something very interesting looking at the sea surface salinity maps of the North Atlantic.  Below, we can see that we are on just the outer edge of the northern arm of the Gulf Stream.  We predict, that once we cross into the 40’s latitudes and past the edge of the Gulf Stream, we will find even stronger currents that will aid us further on our way to greatness!

Stay tuned for more updates soon!

Nilsen & Antonio

Hey All!

So Challenger 1 has made considerable progress within the past few days. Since Friday, Challenger 1 has flown roughly 122km/75 miles, breaking our speed record yet again hitting 0.63 m/s!!

We harnessed the power of the clockwise flow of the Eastern-side of the eddys and are cruising. For the next few days the currents seem favorable, quickly heading in the East – Southeast direction, ever closer to our waypoint.

Today, Antonio have us a few new products that will likely help us even more on our travels.

First he gave us a new Sea Surface Height map takes the european geoid (mean surface height), and calculates the isopotential surface position and from there highlights and predicts surface anomalies.

This will give us another perspective on where the warm and cold eddies are and predicted to go to better our forecast and piloting judgements.

Next we have a new current map that shows the intensity of the vertical attribute of the currents.  So on the map below, the darker red the area, the stronger the currents are moving north, while darker blue means a southerly movement.

As the maps above show, we are still in the reaches of the strong warm eddy we had first encountered late last week that threatened to pull us back out west, but we should officially be out of its reach over the next day or so and continue on our way south.

Also with how well these warm eddies are lined up, we hope to not have to change the way point for a while as we plan to just surf the currents from the east side of one warm eddy to the next until we are out of this solar system.

We will keep everyone updated!

Nilsen , Antonio, and Oliver