College of the Redwoods deploys a new drifter

The students in our Marine Science Technology Program were excited to assemble our new drifter, but their enthusiasm was wavering as we waited weeks for good sea conditions. For those of you unfamiliar with the northern California coast, spring is a rather volatile time. Typically we have strong northwesterly winds at this time of year that fuel the upwelling that sustains an extremely productive marine ecosysytem. The California current (flowing from north to south) sweeps close to shore and gains momentum.  Winter storm winds, on the other hand, approach from the south and often produce a nearshore current (the Davidson Current) that flows from south to north and nudges the California Current offshore. Deploying the drifter involved waiting for the ideal window of opportunity: just after a front, with its southerly winds, sweeps by, and just before the northerly winds reappear to return the ocean surface to chaos.

This spring has been unusually violent and the seesaw of the California and Davidson Currents jockeying for nearshore dominance, and the nearly ceaseless winds, have kept the sea conditions very poor for a deployment.

This is the last week of our spring semester however, and I felt compelled to deploy the drifter before the students dispersed for the summer. We launched yesterday, and the sea conditions were perfect (if you like sea sickness). 10 to 12 foot, short period swells and rather chaotic seas did not, however dim the students’ enthusiasm. The winds (20 to 35 knots) were from the north and the surface flow was strongly southward. We were hopeful that the added influence of upwelling would force our drifter offshore and to the south.

For those of you that have already deployed a drifter, I’m sure you know what the next few hours were like waiting for a satellite fix. By the time our second fix arrived, it appeared our drifter was heading to shore. The students in our program have been conducting cheap, low-tech drift studies for almost 25 years now. We’ve been throwing drift bottles overboard with a printed message asking the finders to mail them back to us. It’s been tremendously successful, and we’ve received bottles from as far away as Alaska and the Philippines. In that time we’ve discovered that certain locations seem to catch more bottles than others.

Last night our drifter was heading for the dreaded Caspar Bay.Check out our Google Map page at: http://www.nefsc.noaa.gov/drifter/drift_redwoods_2010_1.html . By early this morning it was apparent that the drifter had skirted the foul place and was heading south. Past experience has indicated that we have two more major hurdles to bypass if our drifter is going to be in this for the long haul. The next is Pt. Arena, which the drifter should approach within the next day or two. We’re all holding our collective breath. If the drifter misses that roadblock, the next is Pt. Reyes.

In the past, if our drift bottles skirt Pt. Reyes they tend to travel to locations south of San Francisco or into the open Pacific. You’re all welcome to share our tension and excitement. Follow along on our Goggle Map site along with our students and the local community.

If you are an educator, I must say that this is the most excited I’ve seen my students about a single project in a long time. During yesterday’s deployment, the students were getting soaked by waves breaking over the boat’s bow, and everyone of them sported a grin that was, if possible, larger than their face.

Stay tuned for updates as our drifter approaches the much feared Point Arena.

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Drifter Newsletter #6 April 2010

Drifter building and support team

We are happy to have a growing drifter support team to help users with various aspects of the operations. While all members of this team participate in nearly all phases of the process, the specific tasks are as follows:

Southern Maine Community College Marine Science:

  • Tom Long – supervisor
  • Kara LaLomia – lead drifter builder

Gulf of Maine Lobster Foundation (GoMLF):

  • Erin Pelletier – purchasing and billing

NOAA:

  • Jim Manning – lead design and tech supporter
  • Joe Letourneau – programmer
  • Shawn Wolff – assistant tech support
  • Tanya Stoyanova – web developer
  • Grant Emde – field tech
  • Dave Novak – outreach

Marine Advanced Technology Education:

  • Deirdre Sullivan – connection to national COSEE-like initiatives

Since we are all involved with the drifter operations on a part time basis (typically one day per week each), we do not derive our living from the sale of drifters. This is a not-for-profit organization devoted to maximizing the amount of drifters that go in the water and the students who are exposed to the science and engineering aspects of drifter use. If you correspond with Jim, Erin, or Tom via email about any drifter-related issue, please copy all three: james.manning@noaa.gov, erin@gomlf.org, and tlong@smccme.edu so that all three parties are in-the-loop.

New website still under development

While the new drifter homepage is still under development , you can visit it at: http://gisweb.wh.whoi.edu/cgi-bin/ioos/drift/driftTable.cgi . We ask for feedback from you, the participants in this collective effort. We do NOT want to publicize this site until we have heard your feedback and suggestions. Please do not distribute this address to others or link to it from any other website. It may be months before this becomes our primary drifter website. During this transition, we will still consider: http://www.nefsc.noaa.gov/drifter/ as the main page.

Dealing with your satellite bills

There are two options now available to pay for satellite fees:

  1. pay GoMLF upfront for your expected satellite fees and then get billed by GoMLF if you exceed that amount.
  2. get monthly bills directly from the satellite service provider ComTech Mobile.

In this second case, if you are a new user and haven’t got billed from them yet, you need to fill out the ComTech “business agreement” form. To get one of these forms essentially filled out, email Erin (erin@gomlf.gov). Again, please copy tlong@smccme.edu and james.manning@noaa.gov on any emails concerning drifters. MATE participants do NOT have to worry about satellite fees since they are still covered by the NSF grant.

Two Deployment Forms

You need to visit the drifter website both before you deploy and after. Here’s why: If you want to label your drifter deployment with the distinct “deployment ID”, you will need to know what that is. For this you visit the “Plan deployment” site. If you want us to process your deployment and make real-time plots, you need to tell us the exact time and place of the deployment. For this you visit the “Report deployment”. Let me know if you have any troubles with these sites. As with most of our sites, they are “under development”.

New Drifter Users:

  • Center for Student Coastal Research (Cohasett MA)
  • Redwoods Community College (Fort Bragg, California)
  • Falmouth High School (Falmouth MA)
  • Zephyr Education Foundation (Falmouth MA)
  • Atlantic Salmon Federation (St Andrews, New Brunswick)
  • On building drifters from “kits”

Those that have been through it know that building a drifter from a “kit” is not easy. It requires shopping for a lot of hardware that is not supplied and several hours per drifter of labor. To make things easier we have the following suggestions:

  1. new users should either buy at least one complete drifter (as a model to go by) or attend one of our “drifter building workshops” that we have from time to time.
  2. Jigs have been constructed that help with the drilling and cutting
  3. certain tools make things easier like professional drill presses, table saws, and heat guns
  4. ask for our latest “Rachel Construction Document” before you start building

On sealing the transmitter

We recently purchased a machine to vacuum-pack the transmitters in clear plastic bags. This eliminates the need for the white vinyl bags we have used in the last few years and provides a way to insert a readable label. We still wrap the edges of the unit with black tape both before and after the vacuum packing. Users should supply us with the cell phone number that beach combers and mariners should call when they find a unit. We will seal the transmitter so that this number is visible.

Center for Student Coastal Research Project


It took two days for high school students from Cohasset MA (and surrounding towns) to build 15 drifters. These units will be used by the Massachusetts Division of Marine Fisheries to investigate the pathways of lobster larvae in the vicinity of the new LNG terminal in Mass Bay. In exchange for the students efforts, the Cohasset Center for Student Coastal Research will get 6 drifters of their own to deploy in order to investigate the tidal flushing of their local harbor. See photos below and full story at: http://www.wickedlocal.com/cohasset/features/x1060307512/Cohasset-High-students-study-harbor-tidal-flow


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Drifter Newsletter #5

Drifter Newsletter #6
February 2010

Drifter Website Update
We have made some progress in designing a new website to plot all the drifter tracks and to serve the data but we have not yet released it. It will take the place of the rather cluttered site: http://www.nefsc.noaa.gov/drifter/ before the 2010 drifter season gets underway in a few months. Tanya Stoyanova, a computer science student from Bulgaria, is working on it one day per week.

Figure 1. Example of comparing an observed drifter track (blue) with simulated forecast tracks (other colors). In this case, we are using the UMASS-Dartmouth’s FVCOM model output on the “GOM2 grid” provided on the web. We are developing a routine to track particles through their 3-d velocity fields.

Figure 1. Example of comparing an observed drifter track (blue) with simulated forecast tracks (other colors). In this case, we are using the UMASS-Dartmouth’s FVCOM model output on the “GOM2 grid” provided on the web. We are developing a routine to track particles through their 3-d velocity fields.

Collaboration with Coast Guard
Working with SMCC and UMASS-D, we provided the USCG with one of our drifters which they deployed off of Cape Elizabeth Maine in mid-January 2010 (see Fig 1). This was part of the USCG Search and Rescue Training Operations where they practice some of their routines following drifting objects over the coarse of several days. Since we have similar interests for scientific reason (such as following patches of toxic algae), we are trying to combine our efforts in this endeavor. Animation of these forecasts vs observed tracks are linked from the drifter website but may be found directly is at, for example: http://www.nefsc.noaa.gov/drifter/fvcom_sarops.html. If you are interested in implementing this sort of forecast operation in your waters, let us know. All you need is to find a URL for some webserved “CF-compliant” circulation output in your local waters and a MATLAB programmer.

COSEE podcast
Ari Daniel Shapiro’s interview with us including a trip to Casco Bay to deploy drifters was released last week and posted on the COSEE NOW website where it will be heard by many educators and their students around the country. It can be found at http://coseenow.net/podcast/2010/02/drifter/.

New Drifter Deployers
We are happy to add Long Beach Community College from California, Clatsop Community College from Washington State, and the Atlantic Salmon Federation from New Brunswick, Canada to the list of drifter users. LBCC students are actively designing new rigs to radio track bucket drifters in Los Angeles river runoff events. CCC students are following their surface drifters (rachels) rapidly moving north and east of their deployment location off Astoria. ASF will be deploying several drifters in the St Lawrence River in May to track the potential transport of young smolts.

New Transmitters on the Market
We are watching the development of various transmitters such as the new “Spot2” come on the market. There are a variety of options available “off-the-shelf” for doing our sort of tracking but we are sticking to the TrackPack II in 2010. Given its increased battery power this year and improve circuitry, we are hoping it will serve our needs. We will see.

Figure 2. Approximate location, institution, #, purpose, principal investigator, and month of SMCC/eMOLT drifter deployments planned for 2010 on the northeast continental shelf.

Figure 2. Approximate location, institution, #, purpose, principal investigator, and month of SMCC/eMOLT drifter deployments planned for 2010 on the northeast continental shelf.

Drifter plans for 2010
More than 100 drifter deployments will be made this year (Fig 2) to document flow patterns around the Gulf of Maine. Most of the deployments this year will be made in Massachusetts Bay. The state has funded a project, for example, to investigate the potential effects of the LNG facility on the lobster population. We will deploy dozens of drifters in the coastal waters north and south of Boston Harbor. Some of the drifters for this project will be put together by the Center for Student Coastal Research in Cohassett, MA. In exchange for their efforts, they will get several drifters of their own to deploy in their local harbor to examine the exchange mechanisms with the bay.

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The Davidson Current Lives

MPC released its drifter on Nov 14 in Monterey Bay. In the 2.5 months since release, it drifted south, nearly to the latitude of Pt Conception. Then, with the onset of winter storms and the presumable winter-time emergence of the Davidson Current (the slow, northward flowing current that replaces the California Current in the winter months), it has reversed direction and flowed northwards. It now lies farther north than we released it.

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Long Beach City College – LA River Drifter

We are in the final stages of putting together our river drifter.  It’s our plan to use this drifter to show the path that trash takes from the urban areas of Los Angeles County out to the ocean.   The drifter is a hybrid utilizing both the Amateur Radio APRS (http://www.aprs.org ) tracker and Jim Manning’s NOAA satellite tracker.   I’ve pasted a description email below.

From: Scott Fraser [mailto:sfraser@lbcc.edu]
Sent: Friday, January 22, 2010 9:20 AM
To: Jim Manning
Cc: Deidre Sullivan
Subject: RE: on battery power

Hi Jim,
I brought the unit in out of the window on Wednesday night and put it into inventory then configure.  Hopefully I shut it down properly.
I did a bit of research looking for handheld gps units to put in with it and after reading specs, realized that if we run it until the battery dies, that we will likely loose all the saved tracks.  We started talking about putting in a battery pack instead of ballast to power the gps until the unit was recovered.

At that point, I brought out my ham radio/gps trackers that use the ham APRS service.  We did some testing yesterday and have a unit about set up and ready to go.  It will transmit to the ham network once every 60 seconds and will last about 4 days on the battery we have.  The satellite tracker can then be dialed down to give less frequent reports and if it makes it out of the harbor, we’ll let it go for a week or so.

The recovery plan is if close by, to go out and get it; if it makes it to the open ocean, hope that it is recovered and contact made with us.

The ham electronics module (APRS) will be sealed inside two 1/4″ thick acrylic domes today and then foamed into the bottom (top) of a bright orange Home Depot bucket.   The APRS needs a 2m quarter wave antenna, so I got two 18″ bright orange safety flags with wood poles.  We used the pole to run the antenna up under the flag.   The antenna ground plane is a wire along the top rim and a second wire dropping down into the water.   The antenna works great and we are able to hear lots of network stations and able to get into the network also.

Here’s an example of the APRS raw data we put onto the network yesterday

http://www.findu.com/cgi-bin/raw.cgi?call=KN6f-1

On the APRS tracker we were having problems getting it to transmit, so I disabled the “Send only Valid Positions” mode for testing and the last transmission before we shut down shows this unit way up in Canada.  I’ll turn that mode back on today to keep that from happening when live.  We found out that we had a flaky GPS unit and the replacement is working fine.

This link will provide a map of the unit’s current location

http://www.findu.com/cgi-bin/find.cgi?call=KN6F-1

The problem with this service is that once the unit is beyond line of sight communication, it goes dark and we loose it.  That’s where the satellite unit would pick up and take over, so this gets us the best of both worlds.  High rate live reports while in the urban areas running down the river and then low rate tracking once it settles out in the ocean.

We’ll keep you posted
Scott

Scott Fraser
Dept. Chair
Electrical Dept.
Long Beach City College
4901 E. Carson Street
Long Beach, CA 90808
562-938-4505 office

Update: 1/22/10 9:30pm

It was a frustrating day of testing with some success in testing and lots of problems.  It turns out that our 11 year old GPS unit does not function well in cloud cover and rain.  It took some time but we finally correlated the lock periods with times when the sun was out.  At one point there was an awesome double full rainbow on the horizon, but our day was not so awesome.

I’ve ordered a Parallax GPS board that has the sensitivity needed and we’ll swap that our with our “ancient” receiver.

I also had some problems with our second satellite unit not responding to the configuration program.   After numerous trys with and without a passkey I figured that the battery might be dead.  Rather than sending it back to Jim for a replacement, I surgically opened up the case and started checking it out.  The battery voltage was OK at 4.63volts.  So I unplugged the battery and let the unit sit for a minute unpowered.  After plugging the battery back in, I tried connecting to it without a passkey.  It woke up on the second try – YEA!

I set the passkey and was able to take it in and out of operational mode.  Looks like this one is back from the dead.

In doing this I found out that the battery pack is a non-rechargable three AA lithium pack from Energizer.  It has a capacity of about 3000mA hours.  This started me thinking.  I found a solar cell phone charger on Ebay for about $12 (including shipping) that has a 2600mA hour battery pack.  The output voltage is the same as the satellite unit pack.  I’m thinking that on our drifter, I could put the solar cell on the top and connect it to the unit.  It could power the unit for quite a while.

I’ve uploaded some photos of the unit’s insides.

Saturday 1/23/09

It was a bright and sunny day today, no rain!   Dropped by school to see if the GPS unit would establish lock.  It finally did after 10 minutes.  Nothing like 12+ year old technology.  I found a 1997 date code on one of the devices.   Took the drifter for a stroll around campus and was able to record a number of locations over APRS, but it was still spotty.  As soon as the clouds started rolling in, it had a hard time maintaining lock.   So…. with all that in mind.

I ordered the Parallax GPS data logger kit.  We will now have three ways of recording locations.

1. Using the Data logger, a position will be written to a USB flash drive every 3 seconds

2. Using the Ham Radio APRS system, a position will be sent out over the air and onto the internet every 60 seconds

3. Using the satellite transceiver, a position will be sent out once per hour.

We’ll have the satellite transceiver connected to the solar charged battery pack.   Now check my math here.

Jim tells me that the batteries are good for about 1000 transmissions.  Sending one per hour, gives about 41 days per battery pack.  But it may try as many as three times to make a connection so worst case is that the pack would last for about 14 days.

So our worst case is that we use 1/14 of the battery pack per day and best case 1/40.   It looks like a charge time of 0.6 to 1.7 hours per day will be needed to maintain the battery pack.  The solar cell on the pack will charge the entire pack in 15 hours of sunlight.   This is the entire pack.   All I’m asking is a 1/14 pack charge over the day.

That’s it for now. With these changes, we won’t make it in time for this rain storm, but there will be more down the road.

Scott

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Drifter Newsletter #4

Drifter Newsletter #4
December 2009

NOAA’s Adopt-a-Drifter Program
This initiative (www.adp.noaa.gov) has similar objectives to ours in that they engage teachers and students. We are considering ways to merge our respective projects in order to share resources.
In a proposal recently submitted to NOAA’s Northeast Consortium, we suggested a formal collaboration. The ADP program is already connected with NOAA’s Teachers at Sea Program which provides educators an opportunity to sail on NOAA vessels.

Forecasting drifter trajectories
We continue to develop ways to generate forecasted tracks from circulation model output. If your regional association of ocean observations systems has a modeling component and they post their output in “CF-compliant netDCDF” files, there are now means to extract forecast velocities at any point and time in their grid in order to derive a simulated pathways of numerical drifters. To follow the progress of this endeavor, visit http://www.nefsc.noaa.gov/epd/ocean/MainPage/circ/gettrack.html . While much more work needs to be done to make this a user friendly operation, we welcome folks to join us in the open-source development. At this point in time it requires a MATLAB license and some familiarity with that language to run smoothly.

Website revisions planned for 2010
As you may have noticed, the website http://www.nefsc.noaa.gov/drifter/ needs significant upgrades. Since this site started by tracking a single drifter in 2005, it has expanded to become cluttered and unwieldy. We are in the process of developing a sortable table format where users will be able to get a list of deployments and links to the various tracks in the order they prefer (by region, by date, etc). Ideally, we hope to provide automated forecasts and links to animations as well.

COSEE Podcast scheduled for January 2010
Our drifter project will be featured as an “Ocean Gazing Podcast” next month. Ari Shapiro conducted interviews with students and actually went on board to deploy a drifter in Casco Bay this past week. This deployment by the Southern Maine Community College included both a surface drifter (ie Rachel) and a drogued drifter (ie Kara). While the surface unit washed ashore five days later during a storm, the drogued drifter is still underway at the time of this writing. You can follow its progress at http://www.nefsc.noaa.gov/drifter/ by clicking on links to SMCC.

Ocean Science Meeting in February 2010
There were a record number of abstracts submitted for the meeting in Portland Oregon in a few months. While I have submitted an abstract with my colleague Vitalii Sheremet on our low-cost current meter development, I will not attend. If any of you are attending, please track down Vitalii and ask him about his current meter. There are several sessions pertaining to “education” in marine sciences including evaluation of COSEE, for example.

“No Acquisition” sometimes listed on SensService.com
A few of you have noted that “No Aquisition” is occasionally listed where position fixes are not available. I’m not sure why this happens but I suspect that it is occurring either when there is rough seas or when the transmitter’s battery is getting weak. This is just another quirk associated with this generation of TrackPack transmitters. If your transmitter seems to be failing prematurely (ie doesn’t communicate or fails to provide any fixes at all), please send them to me so that I can return them to the manufacturer as a batch. The next generation of TrackPacks (due to be released soon) may correct some of these quirks.

Bristol Community College Drifter In-the-News
As noted on the MATE drifter blog, the BCC deployment story was written up in the news at:
http://www.heraldnews.com/news/x215403522/Bristol-Community-College-uses-device-to-study-ocean-currents and a link to the googlemap was provided. One highlight of the BCC story that was not mentioned in the article is their visit to the local elementary school. See photo below by BCC’s Bob Rak. Dozen’s of children from Fall River MA are following the progress of this drifter!

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Bristol Community College uses device to study ocean currents

By Derek Vital
Herald News Staff Reporter
Posted Nov 22, 2009 @ 10:56 PM

The drifter has caught the attention of the science department at Bristol Community College.

Robert Rak, environmental technology coordinator at Bristol Community College, collaborated with the National Oceanic and Atmospheric Administration of Woods Hole and the Marine Advanced Technology Education Center in Monterey, Calif., to develop a device to study ocean tides.

Continue Reading…

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Now *That* got my Students' Attention

To begin my lecture on gyres and surface currents this morning, I showed them this image.

This data, collected by our colleagues at Cape Fear Community College, definitely got their attention. This is especially noteworthy because we’re getting towards the end of the semester where students are dealing with all kinds of assignments and are just trying to survive. A lecture about gyres and the differences between strong and swift western boundary currents and weak and meandering eastern boundary currents that is usually met with bored indifference was suddenly incredibly relevant.

That track was made in two months folks! Heck, I had no idea the Gulf Stream was *that* fast.

Here’s the same data with current SST data behind it.

Does anybody know where I can get a kml file showing higher resolution SST data for the North Atlantic that would show all of the eddies in more detail?

I did find this kml file, but it is from 2005 and the location of the eddies is quite different.

Thanks!

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MPC Drifter Launched Again

We launched the drifter again this past Saturday. This time we set it to transmit every six hours. We’re hoping that it goes out to sea and goes for a long ride. I find myself experiencing drifter envy over the beautifully long and sinuous path the Cape Fear Community College drifter has taken up the Gulf Stream. I don’t have much hope that the California Current will be able to match that ride, so we’ll have to settle with what we get.

Before the cruise I gave my students this image and asked them to predict where the drifter would be in 48 and 96 hours, hoping the challange would give them experience in calculating distances using the rate equation, as well as piquing their interest in following the drifter’s journey.
MBay circulation model with deployment site
 
We purposefully chose a deployment site where it was a tossup whether the drifter would circulate through Monterey Bay or drift out to sea. There wasn’t a right answer. On the assignment, I merely looked to see that the answers were supported by some sort of manipulation of the rate equation.

Here’s the predictions I got from the students. White locations are 2-day forecasts; purple locations are 4-day forecasts.

On the image you can also see where we intended to deploy the drifter–at the MBARI M1 buoy–and where we actually deployed the drifter; we didn’t quite make it to the M1 buoy in our allotted cruise time.

Today in class, the students manipulated the tracking site and Google Earth to show that the 2-day location of the drifter was almost exactly right in between two of the predictions. So we had two winners. So far the drifter has traveled a few miles SW and then turned around and backtracked to the NE.

Here’s a few pictures of the students deploying the drifter.


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