One of the more impressive earth observation achievements in recent years was the collaboration between Google and the University of Maryland to create a global forest change assessment and visualization. This effort was unprecedented in terms of the raw computing power applied to the substantial Landsat archive, and yielding results that opened a lot of eyes to the change occurring around the globe. Sensors & Systems (S&S) special correspondent Matteo Luccio recently interviewed professor Matthew C. Hansen of the Department of Geographical Sciences at the University of Maryland about this effort that he spearheaded as well as the state of earth observation, global monitoring, and the need for Big-Earth sustainability efforts.<\/p>\n
S&S:<\/strong>\u00a0What first inspired you to become a scientist? Why did you specialize in remote sensing?<\/p>\n Hansen:<\/strong>\u00a0I was into service. I was a Peace Corp volunteer in Zaire and was trained as an engineer. I did fish farming. When I came back from the Peace Corp I decided to go into geography for the simple fact that I like the spatial domain; in particular, I like atlases. I didn\u2019t even know what kind of job you could get in geography, but I knew that I had a natural inclination for it. Within geography, I wanted to do something applied, not basic science.\u00a0 I chose remote sensing, which is very applied:\u00a0 you can clearly see what\u2019s happening at a large scale with landscapes, land use, the way cities grow, the natural hazards therein, the way croplands are healthy or not, the way forest resources are used\u2014it\u2019s just a whole great perspective. My analytical or scientific background, coupled with the idea that this could be a really nice applied information domain, is how I got into it, but the key thing is that it was spatial.<\/p>\n S&S:<\/strong>\u00a0What is your definition of geography? What is remote sensing\u2019s role in the study of geography?<\/p>\n Hansen:<\/strong>\u00a0For me geography is the study of space to understand how we interact with the natural world. It\u2019s coming from the human perspective, because we are the biggest change agents on the face of the Earth. When I was growing up, they said, \u201cThe only object you can see from space is the Great Wall of China.\u201d Actually, all you can see from space is human activity. What\u2019s not modified by humans is a more appropriate question, and there\u2019s very little of that. So, for me it\u2019s the study of the natural space and, more importantly, how humans interact with it. It\u2019s analogous to history, except in space: history is to time what geography is to space. It\u2019s too big a field, really.<\/p>\n Remote sensing gives us a really good, internally-consistent set of facts from which we can quantify these different changing things in geographical space. So, this is a beautiful, wall-to-wall kind of dataset that is not influenced by other strange things that you might find in a set of samples. It is clean. It is a physical, quantitative, wall-to-wall measurement of the Earth. It\u2019s just awesome.<\/p>\n