The Google Earth Time Machine
by Google Earth Blog on Dec.28, 2012, under 3D Models, Argentina, Australia, Brazil, California, Denmark, England, Germany, Google Earth News, Google Earth Tips, Google Sky, Google maps, Hawaii, Indonesia, Ireland, Italy, Japan, Kenya, Mexico, Natural Landmarks, Netherlands, Sightseeing, Street Views, USA
One of my favorite features of Google Earth is the historical imagery tool. Being able to click a button and view imagery from years past is an amazing. If you're not familiar with this feature, here's a quick overview of how it works:
Taking advantage of this feature, Brian Schrock has set up a blog called the Google Earth Time Machine, which shows comparisons of various locations via the historical imagery tool. A great example are the two images below, which show the results of when a dam was placed on the Berg River in South Africa.
He's also posted some animations that make it easy to see the changes to a particular area. A great example of that is London as they prepared for the 2012 Olympic Games. This image shows the area in 2006, 2008, 2010 and 2012:
Brian has posted dozens of examples over the past few years, and it's worth your time to check them out at googleearthtimemachine.blogspot.com.
(via +Google Earth Community)