NOAA Teacher at Sea
Prof. Gina Henderson
Aboard NOAA Ship Ronald H. Brown
August 19 – 27, 2012
Mission: Western Atlantic Climate Study (WACS)
Geographical area of cruise: Northwest Atlantic Ocean
Date: Tuesday, August 21, 2012
Weather Data: Winds light and variable less than 10 kts. Combined seas from the SW 3-5 ft, lowering to 2-4 ft overnight. Into Wednesday 22nd, winds continue to be light and variable, becoming NE overnight less than 10 kts.
Science and Technology Log
WACS Field Campaign Update
Greetings from Georges Bank off the coast of New England! This is our first of 2 sampling stations during the Western Atlantic Climate Survey (WACS) field campaign, over the next 9 days. Our current location was chosen due to its high chlorophyll values, indicating productive waters. Shortly after our arrival here approximately 0700 on the 20th, the Sea Sweep instrument was deployed, and aerosol collection began (see picture below). However, for many of the scientists onboard, data collection began almost immediately after disembarking Boston, on the 19th.
Photographs showing the Sea Sweep (top left), deployment of the Sea Sweep (bottom left), and Sea Sweep underway with bubble generation and aerosol collection taking place (right).
Upon my arrival to the ship in Boston, I quickly learned that this field campaign is a little unusual due to the sheer volume of equipment being utilized, and the short nature of the cruise itself. As we disembarked the Coast Guard pier in Boston, a running joke being echoed around the ship was, “30 days of science in 9 days…. ready, set, and GO!”
Looking from the bow towards the bridge, not visible in this photograph due to the mobile lab vans that have been installed on the deck for this cruise.
Over 9 mobile research vans were loaded onto the Ron Brown in preparation for this campaign making for a “low-riding ship”, joked our captain at our welcome meeting on the 19th. Each van contains multiple instruments, computers, ancillary equipment and supplies, and they also serve as research labs for the science teams to work in.
During the past two days, I have been making the rounds to each of these lab vans to hear more about the science taking place in each. With the help of the Chief Bosun, Bruce Cowden, I have also been able to shoot some video of these visits. With the assistance of Bruce, I am learning how to stitch these clips together into some fun short video pieces, so stay tuned for more to come!
A Little about the Sea Sweep
The Sea Sweep instrument consists of floating pontoons that hold a metal hood. The hood is mounted on a frame that protrudes below the water line when deployed, with two “frizzles” or “bubble maker” nozzles that air is pumped through to produce freshly emitted sea spray particles. These particles are then collected through two intake pipes attached to the hood, and are piped into the AeroPhys van. From there, samples are collected and also the intake is drawn into other vans for additional measurements.
Comparison of Sea Sweep Data with “the Bubbler”
Scientist Bill Keene from University of Virginia talking to me about “the bubbler”.
Sea spray particles are also being produced and collected via another method onboard, allowing for comparison with the Sea Sweep data. The picture below shows bubbles being generated in seawater that is fed into a large glass tower. This is an aerosol generator (a.k.a. “the bubbler”) brought on board by the University of Virginia. Through sampling with both the Sea Sweep and the bubbler, a greater size range and variety of aerosols can be sampled throughout the cruise.
After waiting a day or so for things to settle down and instruments to get up and running, I was eager to dive right in and be put to work on board. After an announcement made by the chief scientist, Trish Quinn, during our first evening meeting I was quickly solicited by a few different people to help with a range of tasks. So far these have included helping change impactor filters necessary for aerosol sampling 3 times a day (1 of these switches has been happening at 0500, making for some early mornings but pretty sunrises), getting raw sea water samples every 2 hours from different sampling points on board, preparing sea water samples for different analysis such as surface tension, and measuring samples for chlorophyll, dissolved organic carbon and particulate organic carbon.
Amongst all the sampling taking place however, it has been nice to take a break every once in a while to enjoy the extremely calm and settled weather we are having. A very memorable moment yesterday occurred when an announcement over the ship’s intercom alerted all aboard to a pod of whales off the port bow. It was nice to see the excitement spread, with both crew and science team members racing to the bow in unison with cameras in tow!
Early morning sky after an impactor filter change (left). All hands rush to the bow after whale sighting is announced (right).