This comment is wrongheaded on several levels. 1: Jet fuel makes water when burned as well: by mass it is ~18% hydrogen, and by energy content it produces 55%

This comment is wrongheaded on several levels. 1: Jet fuel makes water when burned as well: by mass it is ~18% hydrogen, and by energy content it produces 55% as much water as pure hydrogen. The fuel itself is vastly less relevant than the amount burned. > Coal fired plane might be better since CO2 is a much weaker greenhouse gas than water. This is a fundamental misunderstanding of how atmospheric water works. 2. Water vapor -which is a gas- is effectively set; it cannot be affected by dropping water in the air. The amount of evaporated water is only affected by atmospheric temperature. 3. Liquid water droplets in the air are just clouds. Unlike water vapor, clouds are extremely good anti-greenhouse gases. They block visible light but allow infrared through. Seeding clouds with sulfuric acid is one of the suggested ways to fight global warming. 4. Contrails are made of ice crystals, not gas or liquid water. Ice clouds cause greenhouse forcing, but the destruction of ozone and other protective gases from high-altitude radicals in jet exhaust is generally considered a larger concern. 5. This is an area of active research, not something that is neglected. All climate research needs a lot more funding.