You folks have already seen most of this, but for readers of what we call “the print product”, I pulled together today some of my thoughts about the draining of Lake Mead and its implications for New Mexico. I did this (perhaps not coincidentally) as I’ve been pulling together some thoughts to speak tonight at a meeting of the Middle Rio Grande Water Assembly’s executive committee about some of the threads between Colorado River issues and New Mexico.
Here’s the new bit (sub/ad req):
[T]he system is reaching a breaking point. If the lake’s surface drops another 7-plus feet, Arizona and Nevada will begin to see their water curtailed.
How the shortage might affect New Mexico’s share is uncertain. For the next few years, Mead’s troubles are more of a problem for Lower Basin states than they are for us.
But Jennifer Pitt of the Environmental Defense Fund pointed out during a congressional hearing in April that the states in the Colorado’s Upper Basin, including New Mexico, have not sorted out who gets what in the event the shortages get so bad the Lower Basin states issue a demand that we send them more water.
Speaking of drought:
Drought under global warming: a review
Aiguo Dai
Abstract
This article reviews recent literature on drought of the last millennium, followed by an update on global aridity changes from 1950 to 2008. Projected future aridity is presented based on recent studies and our analysis of model simulations. Dry periods lasting for years to decades have occurred many times during the last millennium over, for example, North America, West Africa, and East Asia. These droughts were likely triggered by anomalous tropical sea surface temperatures (SSTs), with La Niña-like SST anomalies leading to drought in North America, and El-Niño-like SSTs causing drought in East China. Over Africa, the southward shift of the warmest SSTs in the Atlantic and warming in the Indian Ocean are responsible for the recent Sahel droughts. Local feedbacks may enhance and prolong drought. Global aridity has increased substantially since the 1970s due to recent drying over Africa, southern Europe, East and South Asia, and eastern Australia. Although El Niño-Southern Oscillation (ENSO), tropical Atlantic SSTs, and Asian monsoons have played a large role in the recent drying, recent warming has increased atmospheric moisture demand and likely altered atmospheric circulation patterns, both contributing to the drying. Climate models project increased aridity in the 21st century over most of Africa, southern Europe and the Middle East, most of the Americas, Australia, and Southeast Asia. Regions like the United States have avoided prolonged droughts during the last 50 years due to natural climate variations, but might see persistent droughts in the next 20–50 years.
Best,
D