Spotlight - Discovering Detailed Ocean Data
The study of climate change has fueled the need for more detailed scientific data, and scientists at the University of Maine are doing their part to try and make it easier to collect some of those data.
UMaine scientists Mark Wells and Carl Tripp, and their colleague Whitney King at Colby College, recently received a nearly $1.3 million grant from the National Science Foundation to continue their work in developing a sensor to measure the micronutrients iron and copper in ocean water.
These metals are important for sustaining the natural growth of phytoplankton — tiny plants that not only serve as the foundation to the marine ecosystems, but also sequester carbon dioxide, the predominant greenhouse gas responsible for global warming.
Currently, the process to measure iron and copper is time consuming, requiring that water samples be collected individually from large research vessels and be brought back to the lab for analysis.
“Even then, you can only get [measurements] from one spot at a specific time,” Wells said.
Compared to the millions of measurements available for major nutrients such as nitrate and phosphate in the ocean, there are only about 3,000 to 4,000 iron measurements, and only about 400 of those are from the deep ocean. There are even fewer measurements of copper.
“Scientists need far more data on iron levels in surface and deep ocean waters to model climate change more effectively,” Wells said. “And there is emerging evidence that copper also will be important in this goal.”
The ultimate goal is to create a small sensor for measuring iron and copper that can be attached to a mooring, to drifting floats that travel vertically to collect data, or to underwater gliders. Gliders would be ideal, Wells said, because their underwater travel is controlled remotely and their data-gathering sensors can run 24 hours a day, seven days a week.
“Until recently, we were a very long way away from developing such a sensor,” Wells said. But his work with Tripp, King, UMaine doctoral graduate Cuihong Jiang and doctoral candidate Eric Roy over the last three years has led to the development of a novel nano-structured surface that is able to selectively bind iron from seawater using a combination of nanotechnology and biology.
“That’s a big challenge because iron in the open ocean is at very, very low levels,” Wells said. “To put it in perspective, we must measure a drop of food coloring added to an Olympic size pool. The difference between a drop and half a drop could have major consequences for how much carbon dioxide phytoplankton can sequester.”
Using the four-year NSF grant, the researchers will modify their nano-structured surface so that it can be incorporated into a prototype sensing device for deploying on ocean observing platforms.
The joint research program will be done at UMaine and Colby College, and will provide both graduate and undergraduate students hands-on experiences in science and research fields.