If aviation emissions were counted as those of a separate country, that country would be ranked as a top ten emitter. The aviation industry’s activities currently contribute between 3.5 and 4.9 percent of total global emissions, and this is expected to increase to 4.4 to 6.2 percent by 2050 under a business-as-usual scenario, according to the U.S. Federal Aviation Administration. (Source: Mongabay)