Earth appears to have a pair of lungs.
NASA recently released this animation showing the Earth’s 12-month biosphere cycle. The video is a little eerie because it looks like the Earth has a pair of lungs — inhaling for one half the year and breathing out for the other.
"On land, the images represent the density of plant growth, while in the oceans they show the chlorophyll concentration from tiny, plant-like organisms called phytoplankton," the animators say.
The animation is a composite of data that was collected from several satellites, averaged over several years.
The video clearly shows the migration of plants north to south due to the changing seasons, with a clear contrast between the north and south hemispheres.
The density of land vegetation in the animation ranges from brown, a minimum, to a maximum vibrant green. The ocean is expressed in a similar manner from dark blue to green. The regions where the land looks barren like a desert are experiencing their winter months, whereas during the summer, there is an abundance of vegetation.
For example, during the northern hemisphere winter, plant life is at a minimum for regions in higher latitudes where there is reduced sunlight. This same trend is visible in the ocean. Meanwhile the southern hemisphere is experiencing summer, so there is lush plant life for both the land and the ocean.
It is interesting, but not surprising, that in the equatorial and tropical regions, there is always an lavish amount of greenery.
Check out the video yourself: