Martha's Vineyard Coastal Observatory

by Tracy Hampton

Because the oceans are so vast, researchers have a long way to go before they uncover the mysteries lying beneath the sea surface. A new observatory on the south side of Martha's Vineyard is now helping meteorologists and other scientists understand the important impacts that oceans have on things like hurricanes, coastal erosion, and global warming.

Wade McGillis of the Woods Hole Oceanographic Institution, or WHOI, has seen the development of the Martha's Vineyard Coastal Observatory since the very beginning. Standing next to the tower by the lifeguard station on South Beach, he acts like a proud father as he shows off its elaborate instruments.

Wade McGillis: "It's about twenty-five feet tall, and the sensors on it measure atmospheric pressure, air temperature, air relative humidity, carbon dioxide. We also have three anomometers up there - sonic anomometers measure the wind speed through changes in sonic velocities - and a camera.

The observatory-s been collecting data since last summer, and now scientists are starting to get some meaningful results about the relationship between the oceans and the atmosphere. Jim Edson also helped get the observatory up and running. Looking out towards the water, he explains how he uses it to study meteorology.

Jim Edson: "So here we are at the top of the dunes, and you can feel the wind pushing on us. It's generating waves off shore, and I'm sure it's generating wave driven currents. And what we're doing with those instruments is that these fluctuations that you're feeling are the turbulence, and that's driving the waves and currents offshore. And we measure that with the sonic anomometer at the very top of the mast.

Edson says the observatory will provide new and reliable data that couldn't be measured before. Usually, scientists who study the oceans rely primarily on boating trips to gather information.

Jim Edson: "Too often, we go out for three weeks and collect data, and we come back and we're never really sure if we see something interesting, is that anomalous, or is that normal? This allows you to put that into context. These are normal conditions for this time of year, or it's not. We're having a warm summer vs. a cool summer.

Data from the observatory will be useful for studying a wide variety of topics from coastal erosion to global warming. For example, McGillis studies the exchange of carbon dioxide between the atmosphere and the ocean, a process at the heart of global warming. He says the observatory is like a natural laboratory, and it's unlike the conditions that're typically used to study his area of research.

Wade McGillis: "What I personally was frustrated with was providing students with a facility that mimicked the real world, so a lot of our research was done in test tanks in the laboratory, and we really didn't have the scales and the right conditions that nature provides. So the observatory provides an immediate access, low cost, facility where they can come up with ideas and implement them. Researchers are already using the facility and as these users spread the word, more and more people will hopefully take advantage of the site."

Scientists and the public can see all of the data the observatory collects - in real time - at the WHOI website. In addition to the onshore tower, there's also what's called a seafloor node. It's a box- like instrument sitting on the bottom of the ocean about a mile offshore. It measures things like currents, waves, water temperature and salinity and other oceanographic variables. Edson says that information is a nice complement to the information they get from the tower on land.

Jim Edson: "When you combine those data sets, that's really when you understand air-sea interaction, sediment transport, beach erosion. That's where we have a chance to do that. We want to be able to predict in cases of severe weather, how much of the beach will we lose? We're not necessarily going to do anything about it but in order to figure out if you want to do anything, you need to understand the processes. We're hopefully coming up with a better understanding of what's happening offshore.

The observatory is designed to withstand severe weather conditions, and it should be in operation for at least twenty-five years with minimal maintenance. Edson says the lifeguards on South Beach are doing a good job keeping watch over it.


Tracy Hampton is a reporter for the Cape & Islands' NPR stations.