It's only 500,000 gallons of fuel. For perspective, 1 inch of rain on 1 acre is 27,000 gallons. So that's only 160 acres at 1/8 inch of rain if all of it came down. Obvious error is I didn't account for density of LOx and LH, just went with gallons because that's what's in the video, but LH is very light and LOx is only slightly heavier than water, so if anything my rainfall estimate is way high.

Do you people realize solar irradiance is so powerful that one hour of it covers all human power consumption for a year?. Do you realize that even with desert and ice caps and fairly low photosynthetic efficiency of plants, at least 10 times more carbon is sequestered than our species emits? Do you realize that most solar energy goes into heating, which is about 1000 times more than gets turned into biofuels for plants? Do you realize what kind of energy it would take to actually form clouds sufficient for widespread rain like they do on a small scale here? Obviously there are ways to tweak what's already there and tease out a rainstorm by introducing condensation nuclei. But if the conditions aren't there we simply don't have the energy available to do a fraction of a percent of what the sun does for weather.