According to China's People's Daily, 97 new airports will be built in China in the next 12 years. That will bring the total number to 244 airports by 2020. At the end of 2006, the number was 147, and it is expected that there will be 192 airports by 2010. This means that 82% of Chinese people will live within 100 kilometers of an airport by 2020.
It's not clear exactly what criteria the People's Daily uses to define what types of airports are included in its count, but if we compare apples to apples and look in the CIA factbook, we find that there are 5,143 airports (paved runways) in the USA vs. 403 in China. That helps keep things in perspective...Still, regardless of who has more airports, it is obvious that the whole sector is fast-growing and will contribute more and more to global warming and air pollution as time goes on. How can we make it greener? How can we keep the many benefits of air travel and reduce or eliminate the negative side-effects?
There are many potential solutions floating around, but we can't know yet which ones will work and which will fail. That's why we must start working on the problem right now and not wait for a more urgent crisis.
As food for thought, here's a possible scenario:
Ground transportation is moving towards electrification (with batteries, hypercapacitors, hydrogen, etc, as storage mediums), because that's more efficient than burning fuel and losing most of the energy as heat. It is also easier (so far) to produce clean electricity than clean liquid fuels.
Unfortunately, airplanes cannot transition to electricity in the way that cars can. That leaves two angles of attack for improvement: Efficiency, and finding another liquid fuel source.
On the first front, many companies are already working on advanced planes based on the "flying wing" or "blended wing" concept. They will carry many more passengers using less fuel, thus reducing emissions per passenger quite a lot. On the fuel side, 3rd or 4th generation biofuels made from algae or specifically selected microorganisms could be used to displace fossil fuels and make air travel carbon neutral (there are already some tests done on using biofuels in airplanes).
This is just one possibility. If you have other ideas on how to make air travel greener, let us know int he comments.
See also: ::Virgin Atlantic to Demo Biofuel Flight, but Not Quite There Yet, ::Future Planes Might be "Flying Wings", ::X-48B Blended Wing Body Research Aircraft Has Lift-Off, ::Boston's Logan Airport Gets LEED Certification