Up on the hill, where it is cold, there is snow. There are also rocks, which heat in the sun.

The hot rocks melt the snow, making lakes of ice, and then heat the ice, making liquid water. Over time, it evaporates or sublimates away, but if this boulder sat above a drain, it would be gathered in. This is better than waiting for spring, as far more can be gathered in this way than is currently in our climate system. Because most of the snow sublimates in the dry air, out of the 65 centimetres that fall each winter, perhaps only 10% goes into the soil in the spring, and that is largely burned away by invasive cheatgrass. This boulder is showing us the way to turn sun burnt grassland slopes into living environments, either with the water funnelling into gravity fed water systems, or being gathered in high grassland wetlands, and used to produce food from there, for us and all the other people.