Rain making Microbes
New research show that microbes, especially bacteria and now fungi are the best at pulling moisture from the sky and making it rain. Dust and dirt particles can help it rain, but they are not as efficient as microbes. A recent article in Science Advances shows how the rain cycle works. Most rain starts as atmospheric water vapor and has to freeze into ice crystals before it comes down, turning into rain. Water in the atmosphere does not always freeze at 32OF. In fact, atmospheric water can stay liquid down to -40OF below zero. Temperatures are much lower at cloud level so clouds can stay full of moisture till it gets cold enough and attaches to something to freeze to cause ice crystals and then turn to rain. “Supercooled” water is a liquid cooler than normal freezing water because it has nothing to hold onto. For clouds to make snow, ice, or rain, it needs a “seed”, a tiny particle for the water molecules to grab onto to form an ice crystal before it falls from the sky as rain. Dust, s...