More snow in the Arctic is good. Less snow elsewhere may be a problem. A new cli­mate model pre­dicts an increase in snow­fall for the Earth’s polar regions and high­est alti­tudes, but an over­all drop in snow­fall for the globe, as car­bon diox­ide lev­els rise over the next century. The decline in snow­fall could spell trou­ble for regions such as the west­ern United States that rely on snow melt as a source of fresh water.