Near our house in Arlington Massachusetts is a nice little park called Menotomy Rocks. It’s a paradise for dogs, with fields to chase balls in, a pond to splash around, woods for interesting smells, and wide walking paths where you can either sniff at or snarl at fellow canines.
Also scattered around the park are several three-foot-high posts as seen above, with a small platform on top and an octagonal disk in the center. These are Picture Posts, a project to have people keep a running record of their environment using their digital cameras. Just as people can contribute to SETI analysis or protein folding simulation, they can contribute data for environmental monitoring. A new form of crowd-sourcing! Imagine if people could contribute to environmental work as productively as amateurs contribute to astronomy.
The way it works is that you place the bottom edge of the back of your camera against the octagon and take eight pictures, pointing in eight directions: N, NW, W, SW, S, SE, E, and NE. Then you take a final picture pointing straight up. That gives you eight views of the surrounding landscape and one of the sky. Then the pictures can be uploaded to a site at the University of New Hampshire: Picture Post Home. You log-in, select where your post is from a Google Map of all of them, browse to your folder, and upload. There’s a good overview of the whole project in IEEE Earthzine magazine here.
The idea is to see what’s happening in the environment over a long time scale. Here’s a movie of scenes from the above post over the last five years, at about 10 seconds per year:
The raw images for this particular post can be found here.
The project provides tools for doing some simple image processing on the images, such as counting the number of pixels of a particular color in a region or doing histograms. They ultimately plan to have tools to do things like estimate the amount of vegetation from year to year, or see the growth in individual trees.
The project started in the early 2000s at a firm called Atmospheric and Environmental Research. They got a grant from NASA to do some general environmental monitoring. In those days NASA required that all projects have an educational component to them, so they came up with this idea. After 9/11 NASA was less interested in this, but one of AER’s researchers, John Pickle, was very taken by the concept. He took it to Boston’s Museum of Science, which set up the first posts in Arlington and Cambridge, and then it migrated to the University of New Hampshire, Durham. The idea for the octagon system came from a former Polaroid engineer, David Bean, who walks his dog in the park all the time. There’s Robert Putnam’s Civil Society in action!
NASA has given UNH a three-year grant to extend the program, which now has about a year and a half to go. It’s now run by Prof. Jeff Beaudry of U Maine and Annette Schloss of UNH. Pickle himself still lives in Arlington, but now is a science teacher at Concord Academy in Concord MA. He has developed a lot of interesting image processing curriculum material, which can be seen here. It’s all part of an informal network called Digital Earth Watch (DEW), which NASA is supporting. This is a much more peaceful and productive project than the old anti-Soviet radar system DEW Line!
The Picture Posts haven’t quite taken off yet. There are about 30 of them, ranging from Quebec to Kansas, but mainly in New England. Pickle thinks that it’s in a Crossing the Chasm phase, where the idea is there, but it doesn’t quite have critical mass. The project seems clearly worthwhile (more so than SETI, if it comes to that), so here are a couple of thoughts on improvements:
- It could use some more software, like a system that generated movies like the above automatically. It would also be nice to be able to immediately compare images from similar dates in different years. Maybe something that charted the number of green pixels over time?
- As can be seen in the movie, the images ought to be aligned and color-adjusted into a common format. The posts could have something like the Gretag-Macbeth color chart on them to provide a color standard. Photographers will hold up one of these charts in their outdoor shoots so that they can correct for the lighting. The charts are expensive and not weather-proof, but something similar could be done with Crayola crayons of standard colors.
- A competitive attitude wouldn’t hurt. SETI@home does this by scoring how fast your processor is compared to others. Maybe there could be a list of who has taken the longest consecutive series of daily or weekly pictures.
- A social network aspect wouldn’t hurt either, E.g. by being able to comment on one another’s pictures, or posting the analysis that you’ve done of your images.
But the main thing at this point is to just get the data. As Pickle said, “Imagine if we had a set of photographs of what has happened to the land from the 19th century on, even if it was just in one place! What we could learn about how our world is really changing.” Satellites can do it, but nothing beats ground truth. Here’s a way that citizens could contribute to one of the most important scientific issues of our time.