Oceans: The Great Unknown

Who Are NASA's Earth Explorers?



The elementary school student wondering how El Niño will affect tomorrow's weather. The scientist studying connections between ozone and climate change. And the farmer using satellite pictures to keep track of crops. All of these people are Earth Explorers -- they are all curious about the Earth system. This series will introduce you to NASA Earth Explorers, young and old, with many backgrounds and interests.

Dan Stillman, Institute for Global Environmental Strategies

Gene Feldman has studied the ocean for 25 years. He does this mainly by looking at satellite measurements of ocean color. Different ocean colors indicate different levels of plant growth in the ocean. We know more about the oceans than we used to. Yet we still know "very little about the vast majority of the ocean," he says.Earth Explorers recently spoke with Feldman. He had just returned from a trip to the Galapagos. The Galapagos are a group of islands in the Pacific Ocean along the equator. The islands are known for their unique and diverse mix of wildlife.Feldman has for many years explored the Galapagos by satellite. But never before had he seen the islands in person. So when he was invited there to take part in a conference and research cruise, he couldn't refuse.We asked Feldman about his trip to the Galapagos, how he first became interested in the oceans, his advice to young scientists, and more.Of all the places in the world, there's probably no place like the Galapagos. Because of its unique location and the influence of ocean currents, the Galapagos have allowed species to evolve in ways that can be found nowhere else. Where else can you find penguins and coral reefs in the same location?While anchored for the night under the steep volcanic cliffs, the only sounds I heard as I fell asleep were the crash of the waves on the shore and the bark of the sea lions. A splash of wave against rock, the creak of the ship's wooden deck, a bird's call from overhead, a sea turtle surfacing alongside the boat are just some of the sounds that fill the night.I've always been attracted to the ocean. I really think it all started when I would spend summers with my grandparents. My grandfather loved fishing, and he would often take me with him. I remember sitting on the beach with him hearing the gulls and watching the waves come ashore. I would wonder what was out beyond the breakers, what was down there below the surface.In high school, I started realizing that I actually could do something with this interest that I had in the ocean. My school didn't offer any oceanography classes. But I did find ways to get out to sea. One of the things I did in high school was to go out on fishing boats, just to see what it was like. Then when I got into college, I went out on as many research cruises as I could. I jumped at every opportunity to get out on a boat or get involved in some kind of ocean research.Earth is really an ocean planet. Life on land exists in this thin layer that begins a few feet below the surface of the soil and extends up into the tops of the trees. But in the ocean, life is found all the way from the surface to the very bottom of the deepest part. The deepest part of the ocean is nearly seven-and-a-half miles down. Because of this, the oceans contain 99 percent of the living space on the planet.Our knowledge about the oceans and technology to study the oceans these days is so much more than they were when I was in school. Back then, the most common way to sample the ocean was to drag a net through the water and see what was caught. Or you could lower some bottles over the side and pull the water up to see what it contained. There were no satellites studying the oceans.But even with all the technology that we have today -- satellites, buoys, underwater vehicles and ship tracks -- we have better maps of the surface of Mars and the moon than we do the bottom of the ocean. We know very, very little about most of the ocean. This is especially true for the middle and deeper parts far away from the coasts.It's really a hard place to work. In many ways, it's easier to put a person into space than it is to send a person down to the bottom of the ocean. For one thing, the pressure exerted by the water above is enormous. It's the equivalent of one person trying to support 50 jumbo jets. It's also dark and cold. Unlike space where you can see forever, once you're down in the ocean you can't see anything because your light can't shine very far. It's a challenging place to study.Satellites are great for giving us that broad picture of the surface of the ocean. We can measure temperature. We can measure ocean color. We can measure the winds, the waves and sea level. But what we currently can't do from space is look down into the depths of the ocean in 3-D.Never stop asking questions. Our curiosity about the way things work will guide technologies of the future. There's always going to be the need for scientists to go out to sea, or to go under the sea. But we also need people to help evolve the technology to allow us to study places that are hard to get to.Computer models are the way that we try and predict what Earth will be like in the future. So people are needed to understand how to build better and more accurate computer models.Science is sometimes presented as how much we know. It can often give kids in school the idea that we have all the answers, that we know everything to know about Earth. I disagree with that. There are things about this wonderful planet that are still a mystery. There are questions that can keep scientists busy for as long as there are people on this planet. And we'll still not have all the answers, because the world keeps changing.So much more is yet to be learned about this amazing planet. Every time we turn over a rock, there's something new. Every time we explore some place new, there's something we've never seen before. Every time we think we understand the way things work or fit together, more things pop up that we don't understand. Science is puzzle solving. It's really fun trying to figure out how things work and how everything fits together. More importantly, it's the only way that we can take care of this amazing place we call home.