Fire benders are shown to be able to bend lightning by manipulating the... something in fire (I dunno, density, electron alignment? I dunno). so logically, the airbenders would be able to bend something that contains air on a less significant level than regular air (ignore chemical makeup, it gets too damn confusing on what they're actually bending)
In the airbender world, There are four manipulable elements (earth, fire, air, water) that everyone knows about. (btw, that video is great Wight, helped me figure this next part out.) There is also the bending of spirituality, which is a metaphysical concept, the state of spirituality, but that's not any more important right now that to note that it's a metaphysical concept. So we see the incorperation of the four classical western elements, and the incorporation of the metaphysical role of spirituality. Here is where I start to lose track of things a bit, because of my knowledge of how our world works and my want to apply my understanding of my world to a cartoon fantasy world.
Literally nothing in the Airbender world works the way our world works. It may look like it, it may act like it, but in my belief, the chemical (idea) makeup is different entirely. The four elements exist along with metaphysics, but these elements don't interact chemically the same as ours do. The result is the same when you put water on fire, but the process was different in my opinion. This belief spawns from the FACT (until I'm proven wrong) That water benders can't manipulate air, even though it has oxygen, fire benders can't manipulate air even though it possesses carbon dioxide, Earth benders cant manipulate anything but earth (even though they can turn stone to liquid (as evidenced by the piece of meteorite Sokka gave to Toff) at will), and Air benders cannot manipulate any of the other elements directly. therefore, in the air-bending world, I theorize that these are not the same compounds that make up our atmosphere, and we should rather treat them as being separate in chemical structure. Now, by stating this, I can also make the claim for spirituality.
Minor detail from book 3 of LoK
Spirituality determines why a person is attuned to which element, or to none at all. People born with an affinity for earth, if they possess the right capabilities, are able to bend the element of "earth". (it should be noted here that I do not believe that elements work the way ours work in this universe either) This applies to all of the elements.
Major spoiler from book 3 of LoK
A list of interesting techniques for each element, shown so far in canon, book 3 of LoK inclusive
The first three episodes of Book 3 of LoK have aired. You can find and watch them, now. Episodes four through six are available in Spanish audio, and there are English summaries for each episode (and I believe that there is also an option for you to download the episodes along with English subtitles for VLC, yet I cannot confirm this, myself).
"Choosing to do as little as possible means concisely limiting your contribution to the inevitable dispursal of energy and thus, in a teeny, tiny way postponing the heat death of our universe. Relaxing adds time to the universe's life..." - Michael Stevens