From this morning’s Albuquerque Journal, a story (sub/ad req.) about new research suggesting that, in the past, the jet stream moved north and what is now the southwestern U.S. dried out when the world was warmer:

For 45,000 years, the drips built stalactites and stalagmites in Fort Stanton Cave. The minerals in the rocky deposits recorded traces of dry and wet spells above, according to Yemane Asmerom, a professor in UNM’s Department of Earth and Planetary Sciences.

The scientists wrote last week in the journal Nature Geoscience that their finds suggest that a warming planet “could lead to increasingly arid conditions in southwestern North America in the future.”

Yemane’s paper and another recent one by Wagner et al. tell a story that’s consistent with the model projections of what might happen in a warming world, and with data suggesting the jet stream already is moving to the north.

If you look at the supply-demand numbers with respect to western water, demand growth still dominates this equation, and natural variability remains an enormous part of the problem in terms of coping with supply’s ups and downs. But this message about the long term supply trend has been growing much more clear in the 15 years I’ve been writing about this