You’ve seen the data that comes from doing a CTD cast. But how do we actually collect the data? We have to put the CTD in the water very carefully, to avoid damaging our instruments or our ship. To do that, we use a winch, which includes a pulley (remember those, 6th graders?). Here’s a video of the process:
A few highlights:
- The guy making the funny hand signals is Drew. He’s our Resident Marine Technician, or restech. The hand signals tell the winch operator what to do.
- That’s me in the lower right corner! I’m running a tag line, one of the ropes that keeps the CTD from swinging too wildly. There’s not much risk when the seas are calm like they are in this video, but you can imagine what happens in rough seas. The other tag line is run by Gerald, who is a member of the Philippine Coast Guard.
- Look at the CTD going down in the water. Can any of the 7th graders tell me what is happening to the light underwater to make it look like that?
- I left the soundtrack as it was so that you could hear what we hear. Ships are loud places.
Finally, thanks to Alette for filming!