Did you ever wondered what was the population density in 2000 or how the temperature across the globe changes? If you did you should know that Google Earth satisfies all your curiosities because as people down at Google say Google Earth isn't just mapping software; it's a powerful tool for viewing, creating and sharing interactive and highly visual location-specific information.
You can discover a lot of things through Google Earth's sidebar but a lot more wait at the
Google Earth Gallery.
World Population DensityExploring America's OceansExplore Arctic Drilling 
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