Dear Umbra,

There’s a Hot Air Balloon Festival going on in the Hudson Valley right now and I’m watching balloons out my window wishing I had the nerve to go up in one, while also wondering how bad they are for the environment. This isn’t just mild curiosity; you could literally make or break my future relationship with hot air ballooning. It’s funny how my fear of heights would actually diminish if riding in hot air balloons were shown to be beneficial to the environment! For now I’ll just take pictures.

Melissa
Poughkeepsie, N.Y.

Dearest Melissa,

Hot air balloons work on one of two principles. The “hot air rises” principle is at work in balloons with propane tanks aboard; the propane heats the air, the air rises, the balloon floats. The “some gases are lighter than air” principle is at work in balloons with helium or hydrogen aboard; the balloon is filled with one of these gases and floats. The first are called hot air balloons, and the second are called gas balloons. A victory for creative nomenclature, truly.

Full of hot air.

Propane is a relatively clean fuel, but balloons use quite a bit of it in flight — an amount roughly comparable to running your gas grill for almost three days. As we know, walking is probably the least deleterious outdoor entertainment. No, I take that back. Sitting in a hammock is probably less damaging to the environment than walking. But many other outdoor entertainments entail emissions or other negative impacts: driving to the beach, water skiing (two-stroke engine!), driving around to look at the fall colors, skydiving. I’m going out on a limb here (another fun, low-impact activity), since I haven’t found a big chart comparing hot air balloon flight to all other forms of fun, but I will venture to say that ballooning is not an environmental disaster. However, your fear of heights might increase when you check out the average price tag for a balloon ride. My enthusiasm was deflated rapidly.

Dangly,
Umbra