Change Detection is designed to compare the spatial representation of two points in time and measure changes caused by differences in the variables of interest.

Are you running a satellite images search to look at a city district? Or an agricultural field whose geographic coordinates you’ve captured with a smartphone? Or do you need an image of an uncharted iron mine that can’t be found on a map?

Latest satellite imagery is the most sought-after data right now, but historical satellite images are the ones you need to see how a site has changed over time. And the good news is that millions of archived satellite images of nearly any place on Earth can be accessed free on the Internet.

We live in a wonderful era when absolutely anyone can access the latest free satellite images of Earth; it only takes to know where you can find them. Our best seven free GIS data sources list will make it easier to decide which of the available web services has the data you need.

So you’ve decided to start using satellite data but have absolutely no idea what kind of image has the information you need? Our first tip is: figure out what spatial resolution is good for you.

With large amount of satellite imagery and analytical software becoming freely available, even small forest organizations or forestry specialists can leverage the remote sensing technology to monitor land use and protect global forests.