Bancroft Arnesen Explore & Roald Amundsen High School[/caption]
The modern drifter is a high-tech version of the “message in a bottle”. It consists of a surface buoy and a subsurface drogue (sea anchor), attached by a long, thin tether. The buoy measures temperature and other properties, and has a transmitter to send the data to passing satellites. The drogue dominates the total area of the instrument and is centered at a depth of 15 meters beneath the sea surface.
Determine if you have found a drifter, as opposed to some other floating device.
The spherical float is 30-40 cm in diameter, is always made of plastic or fiberglass, and will have an identification number on it (usually five digits). The color of the float is not standardized: it could be bicolor, like the drifters shown on the top of this page, or it could be solid black or blue. It may have a tube on the top which houses the barometer, or it may be spherical. It may have two metal screws on the top hemisphere. It will always have a metal instrument (the thermistor) extruding near the bottom (you can see this on the white-and-red drifter in the top left picture on this page, surrounded by a small cardboard ring that falls off after deployment). At the very bottom of the float there is a rubberized “carrot” that connects the tether . . . or there will be evidence that this was once there, but has been broken or cut. Often, the subsurface drogue (sea anchor) will be gone from a drifter that has washed ashore; this may still be attached to a drifter recovered from the ocean. Drifters that have been floating for some time accumulate biofouling and may not look as clean as they looked when they first were deployed. This is a picture of a drifter that was on the water for 521 days and was recovered.
Here is a list of things to do if you have found a drifter and you have it in your possession:
- Look for any identification(usually a 5 digit number), or instructions on the surface of the float.
- Take a picture of the drifter and all its components.
- Contact Drifter Webmaster and send a picture and as much information as you can.
- You can find deployment information about any drifter in our web page: Deployment_log