Where did the water come from and where does it go?
These are the main questions we are trying to answer to help us better understand near-surface ocean circulation.
Being able to answer these questions has applications in navigation, pollution monitoring and abatement, search
and rescue, and plankton and clam larvae drift.
One way to better understand near-surface ocean circulation is to deploy surface drifters - these come in various
designs and are placed in the ocean with their location tracked as they drift along with the prevailing surface
currents, wind, and waves. Drifters of various kinds have been deployed by Fisheries and Oceans Canada in the
Pacific Ocean since the 1950's.
One of those early drifters - a simple message in a bottle - was just recently found.
This was drift bottle No. 25263, one of 33449 bottles released over a four year period, detailed in this
Finders of the drift bottles were guaranteed a reward of $1.00 no matter where the card inside the bottle was sent from,
and some recoveries were made as far as 1500 km away.
Here we document a drifter program that began in 2014 that has involved drifter
deployments throughout the Northeast Pacific Ocean, but has also included a few in the Northwest Atlantic Ocean, Western Arctic Ocean,
Norway, Taiwan, and the Southern Ocean.
Found a Drifter?
Have you found a drifter? Does it look like this?
Surface Circulation Tracker (SCT)
Surface Circulation Tracker (SCT)
If the drifter is floating freely in the ocean, please LEAVE IT ALONE. It is probably collecting data and
reporting its location back to us via satellite. If you can, please take a picture and send it to us, along with
where and when you saw it to firstname.lastname@example.org.
If the drifter is floating in the ocean but tangled up in flotsam, please untangle it, (reshape the round
aluminum tubes below the waterline if necessary in the case of an SCT drifter,) and put it back in the water. If
you can, please take a picture and send it to us, along with where and when you saw it to
If the drifter is washed up on the shore, please recover it so we can recycle it. If you can, please take a
picture and send it to us, along with where and when you recovered it to email@example.com. We will
send you a prepaid envelope so you can send the drifter back to us. (In the case of an SCT drifter, we only wish
to recover the SPOT Trace and plastic bracket that holds it. These are the black plastic parts on top of the
spring on top of the drifter. The rest of the drifter can be disposed of in the municipal waste.)
Many thanks for your help!
For more information on the program you can see this news story: https://www.saanichnews.com/news/hundreds-of-floating-sponge-bobs-help-track-ocean-currents/
Drifter recoveries in the news:
On the Powell River story, above, see also:
You can search and display drifter tracks (and access the data) here: https://dmapps.waterproperties.ca/en/drifter/.
You can also access the drifter track data through the Water Properties website: https://www.waterproperties.ca/data/
. Select Data
, Search Data Holdings
, and from the Metadata panel, select Metadata Name=Data Description
, Value=Drifting Buoy
. Note that you will need an account to access the data and the data are not available in real-time.
Below are shown annual summaries of drifter tracks.
Drifter Tracks in Google Earth
Drifter tracks can also be displayed in Google Earth. Tracks have been separated by year into kmz files, and are displayed in three different ways:
As simple tracks with each track a different colour.
As above with but beginning, ending, and possible found locations also indicated.
As animated gx tracks.
2014: Simple, Begin/End, Animated gx
2015: Simple, Begin/End, Animated gx
2016: Simple, Begin/End, Animated gx
2017: Simple, Begin/End, Animated gx
2018: Simple, Begin/End, Animated gx
2019: Simple, Begin/End, Animated gx
2020: Simple, Begin/End, Animated gx
2021: Simple, Begin/End, Animated gx
Hourston, R.A.S., Martens, P.S., Juhász, T., Page, S.J. and Blanken, H. 2021. Surface ocean circulation tracking drifter data from the Northeastern Pacific and Western Arctic Oceans, 2014-2020. Can. Data Rep. Hydrogr. Ocean Sci. 215: vi + 36 p.
Blanken, H., Valeo, C., Hannah, C.G., Khan, U.T. and Juhász, T., 2021. A Fuzzy-Based Framework for Assessing Uncertainty in Drift Prediction Using Observed Currents and Winds. Frontiers in Marine Science, p.1677.
Page, S.J., Hannah, C., Juhasz, T., Spear, D., and Blanken, H. 2019. Surface circulation tracking drifter data for the Kitimat Fjord system in northern British Columbia and adjacent continental shelf for April, 2014 to July, 2016. Can. Data. Report. Hydrog. Ocean.Sci. 328: vi + 33 p.
Pawlowicz, R., Hannah, C. and Rosenberger, A., 2019. Lagrangian observations of estuarine residence times, dispersion, and trapping in the Salish Sea. Estuarine, Coastal and Shelf Science, 225, p.106246.
Frequently Asked Questions
- Q. I found a drifter, what should I do?
- A. Please see the Found a Drifter section.
- Q. How many drifters have been deployed?
- A. Over 1000 drifters have been deployed since 2014.
- Q. Where have they been recovered?
- A. Please see the Recoveries section.
- Q. What do the drifter tracks look like?
- A. Please see the Drifter Tracks section.
- Q. Where can I access the drifter track data?
- A. Please see the data section of the Water Properties website: https://www.waterproperties.ca/data/. Select Data, Search Data Holdings, and from the Metadata panel, select Metadata Name=Data Description, Value=Drifting Buoy. Note that you will need an account to access the data and the data are not available in real-time.
- Q. Why are the GPS transmitters on SCT drifters mounted on a spring door-stop?
- A. The GPS transmitters only relay their location to satellites when they sense movement. Usually wave action results in enough movement of the drifter to ensure it keeps transmitting its position, but in some cases a calm sea state is not enough. A door spring ensures the GPS transmitter moves enough to stay active and keep transmitting its location.
Plotting software courtesy of R. Pawlowicz:
Pawlowicz, R., 2020. "M_Map: A mapping package for MATLAB", version 1.4m, [Computer software], available online at https://www.eoas.ubc.ca/~rich/map.html.
Drifter data processed using drifteval software provided by R.Pawlowicz, see:
Pawlowicz, R., Hannah, C. and Rosenberger, A., 2019. Lagrangian observations of estuarine residence times, dispersion, and trapping in the Salish Sea. Estuarine, Coastal and Shelf Science 225, p.106246.
Page last updated: Aug.11, 2022.