Yes, as a teaching project for students there are all sorts of great things you can get them to start working through and thinking on. For that I can see *lots* of valid uses

I looked at your website and it looks great.

Just a couple suggestions for other runs:

Have them take one pic looking down at the card and another showing the area with the horizon center on the picture. Then you can link that into a discussion of both site classification and the sky conditions.

Have one at noon and dusk (or dawn) to compare the differences in the light incidence.

It would also be a great chance to have the students come up with their own experimental methods and explain the aspects of methodology selection.

clouds: Personally, I would love to know more about cloud cover and albedo – I know there are several research groups that focus on this, and I have been culling the library stacks to learn more. For now, it’s okay. Since I could go into weather databases and find conditions for each image if the need arises, in an ideal world there is the potential for other data mining at a later date. Humidity is another factor that I wonder about. I have no knowledge, but water is a greenhouse gas and I think it could be an interesting thing to research.

Time of day: over a single day, there does not seem to be a significant difference in the results. The extremes are, of course, when comparing the first and last photos. This would be consistent with the angle on incidence changing. Hence, the decision to give a time range.

There is absolutely no argument that there are myriad parameters to control. Again, for the goals of this project the do not APPEAR to be of the magnitude that nullifies the project. As I get more data, I will no more and, as noted, refine protocols – and maybe even goals. At this point, I stand by my project, and think there is a lot of utility in both encouraging people to become involved, for both an overall science involvement, as well as to think more about climate change.

Please do not hesitate to contact me, if you have suggestions for ways to improve this, or new experiments to try, etc.

If you’re interested in the Earth’s albedo, satellites measure it. (Although that’s a messier and less accurate affair than one might imagine, too.) If you’re interested in the albedo of various common surfaces – grass, concrete, sand, etc. – then there are tables. The values have been measured with better instruments under controlled conditions.

I’m sure that with a number of additional measures, a digital camera could indeed be used to measure surface albedo reasonably accurately. It’s not going to be a simple experiment to perform, but I expect would be within the capabilities of schools to develop and teach. But the main reason it’s a nonsense is the sampling issues. A few snaps of people’s back lawns are not going to tell you anything about climate, no matter how accurately you measure it. It’s really all about the teaching.

The project started as an outgrowth of a classroom project – my first class results were examined by a colleague who is an expert in the field, and he was intrigued. He asked if I would continue doing this, and could I get a larger data set. At the time, I had no intention of “going public.” Then, when I wanted some more data points for a talk that I was giving – before my students would be back in school – I created a Facebook event. The response was great, and I submitted this project to become my official project for NOAA Climate Stewards program. Even before that approval came through, this medial support developed. And I am thrilled to have people excited to be involved.

As for earlier school data – I am reworking photo name for privacy, so that it can be displayed, too.. And note that even if I get street level lat/long, I do not post or submit it that way, so that other’s privacy is protected as well.

I am happy to answer questions and address concerns as best I can.

I am usually prone to being skeptical as well on initiatives like this, but I actually am also familiar with some of the drawbacks and gotchas since it was the area of my MS thesis. My first reaction was quite similar but once I thought about it for a while, it turned into, “Hey, this might work really nicely for some stuff.”

Crowd sourcing is one of the really cool and new untapped resources for large scale science.

You are right – and I have done the experiments with, so far, 20 different types and manufacturers of common white papers, index cards, and business cards – including photo papers, construction paper, and card stocks. White is not white. However, the results for all the matte white paper and cards agree within plus or minus 1%; Glossy paper is the worst because of overexposure potential. Construction paper is about 5%. These are repeatable and reproducible. (my background is analytical chemistry) The concerns you address about keeping a common reference are what led me to do this – so that, indeed, it could be used with a wider group of people.

As for the spectral range – I am fully aware of that; again, because the control is in each picture, the effect is minimized for these qualitative analyses. Since the goal of the project is to raise awareness and to help people understand that they can understand that they can make informed choices (and maybe even learn some science along the way)

Since I am a full time educator, I fully admit that website development has been slow – When this project so happily and surprisedly mushroomed on me, I have been frantically researching and writing content in all available time. I intend to address the concerns mentioned on the site, with data and references.

Just the skeptic in us looking at all the things that need to be in place before the result will mean something, based on our areas of knowledge and the issues we are personally aware of.

And I agree with Nullius in that if it gets people to actually start being involved and get their brains turned on I’m all for it.

It’s also interesting we aren’t saying one couldn’t do anything with this, but rather a list of issues that need to be addressed before we could call the results valid…

Yes, I was avoiding getting in to the raw details as this is not the appropriate forum but the light source is going to be the same (sunlight) and the angle of the paper is going to be approximately the same (up) and the paper will all be about the same (white).

There will be variations from the sources that you mention along with many more such as reflected light on nearby items, altitude, slope of the ground if taken on the ground, the actual algorithms for image processing and often compression. Even the random seed for the algorithm. Individually, there is too much variation to depend on. As an average over many images, that variation approaches zero. When you look at a satellite image, one pixel will be the average of a much larger area (depending on the magnification and distance) with potentially greater variation and has the same problems. With new techniques like this crowd sourcing, we don’t even have a starting point to examine it’s potential until there are some test runs. The methodology will improve as experiments like this run. Rather than it being able to “Help the planet” or not is immaterial but a good way to garner involvement. It is really more in the line of basic research. Until we do it, we have no idea what it is capable of.