Atmosphere of Earth development of animals. Today's atmosphere contains 21% oxygen, which is great enough for this rapid development of animals. "Air pollution" is the introduction into the atmosphere of chemicals, particulate matter or biological materials that cause harm or discomfort to organisms. Stratospheric ozone depletion is caused by air pollution, chiefly from chlorofluorocarbons and other ozone-depleting substances. The scientific consensus is that the anthropogenic greenhouse gases currently accumulating in the atmosphere are the main cause of global warming. On October 19, 2015 NASA started a website containing daily images of the full sunlit side of Earth on http://epic.gsfc.nasa.gov/. The images are taken
Runaway greenhouse effect will be two variations of this future warming feedback: the "moist greenhouse" where water vapor dominates the troposphere while water vapor starts to accumulate in the stratosphere, and the "runaway greenhouse" where water vapor becomes a dominant component of the atmosphere that the Earth starts to undergo rapid warming that could send its surface temperature to over as the atmosphere will be totally overwhelmed by water vapor, causing its entire surface to melt and killing all life, perhaps in about three billion years' time. Either way, the loss of oceans will inevitably turn the Earth into a primarily desert world