Summer Camps: Exploring Messy, Wonderful Science
Salish campers had the chance to design, build and deploy data buoys
A guest post by Education Director Dan Hannafious, describing the process of designing, building and deploying data buoys during the recent Salish Sea Science Explorers Camp held on Bainbridge Island.
A large bucket of PVC pieces and parts is noisily spilled at the feet of the circle of Salish Sea Expeditions Science Campers. In a flash, campers are reflecting on buoy design, flotation, sensor positions, line length, anchoring, tidal change, depth of deployment… and in their eyes you can see: “oh, this is going to be fun!”
Leading up to that moment, there were conversations about why build and deploy buoys? How will the minus tide this week affect our deployment? How can the sensor positions provide the “coolest” information?
The campers had been collecting water samples throughout our week-long exploration. Some samples were collected in the forest ponds. Some were collected in the small drainage coming down the hill from the forest. Others were taken from the water seeping onto the beach, and yet other water samples were collected from the marine water. Campers used a Niskin bottle from a small inflatable boat to collect the water offshore, the same Niskin bottle used by scientists aboard the large research vessels that study the oceans of the world.
Our explorers used pH probes and thermometers to better understand the water samples they had collected. They tested the water for nitrates, phosphates and copper using reagents and a colorimeter to record the ppm value (parts per million). They recorded the values from each sample bottle in their journals. Some values were high, others were low. The values painted a data picture that was then shown as a story through graphs. The data stories created as many questions as there were answers.
It was an “A-ha!” moment in understanding the scientific method and how science often works. Campers understood that the data values were a moment in time for those particular sample locations. “Wouldn’t it be cool if you could record values over time? Wouldn’t it be cool if there were sensors that could log data over time?”
Enter the data buoys!
Teams of science campers reached for the PVC pieces and started to fit angles and lengths together to resemble a design they sketched in their journals. Shortly, they would be testing the flotation properties of their buoy, while standing knee deep along the shoreline. A few teams needed to make adjustments. A sensor was carefully attached, and ready to record temperature and light data from the watery depths. By the end of the afternoon, each team was ready to deploy their buoy from a boat into water of a measured depth.
The moment of deployment: One team member called out “six feet!” as the measuring line hit the bottom. Another team member slowly lowered the anchor until it hit bottom. The rest of the line slipped over the side and lastly the buoy is lowered over the side of the boat. The team quietly watched it move slowly away. They seem a little bit nervous and a little bit excited. The silence is broken as two of the team members started paddling back to shore. The temperature and light sensors started logging information until they were recovered the next day and over several tidal cycles.
What will that data story reveal?
The revelation
We learned that science doesn’t always reveal a clear story, and the best laid plan doesn’t always play out as expected. Science can be messy. Experiments can be messy, as the student scientists discovered when they found a raft of macro algae surrounding their experiment. The sensor just below the surface was in darkness: “Arrgghh!”
The student scientists also came to realize the recovery of data is not as simple as holding the recovered sensor in the palm of your hand. The technology seemed commonplace at first glance to the campers, but it still took time to sort the serial numbers of the numerous sensors, use the wireless docking station to download the data, establish the file naming convention to store each batch of data, and then plot the data graphs. “I didn’t realize science would be so repetitious,” one camper said to heads nodding in agreement.
With data plots graphed, the campers were able to look at their data stories. The more obvious features within the data plots were the time of the sunrise and sunset, but even that was obscured from some of the sensors. They learned the sensors above the water provided some reference for the sensors under the water, but the data story under the water had some interpretation challenges. As expected, the water temperature just below the surface followed the air temperature as the sun went down. What wasn’t so expected is why the temperature at depth was slightly warmer than the temperature at the surface. There was a long moment of reflection when asked if the minus tide during an 80 degree day might possibly affect the temperature of the deep water when the tide was rising again. Data is complex, and sometimes messy.
The student scientists were reluctant to disassemble their buoy creations. They had just spent the better part of two days getting to know this thing they created. They had duct taped the flotation, tested their design, zip-tied the sensors, measured the line, tied the knots and affixed their team flag. The grassy area was once again messy with pieces and parts as camp wound to a close.
As much as we, as parents and educators, hope to create experiences for our explorers with clear results, the world is notably more full of gray than black and white. We at Salish Sea Expeditions strive to create relevant life experiences that require students to think about outcomes beyond what they may expect. We are grateful for our campers and students and their curiosity, persistence and ongoing exploration.
After a fun week of learning, I am looking forward to more adventures in messy science when our school programs start up again in September. I hope to see these scientists-in-training on a future Salish expedition. Happy summer!
