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Monthly Archive | CLIMAS

Monthly Archive

Colorado River Delta: Pulse Flow - One Year Later

Wednesday, April 22, 2015
Emily Huddleston

The Colorado River Delta hadn’t seen regularly flowing water in 50 years.  But one year ago the U.S. and Mexico came together to work on a project to move water down the empty riverbed.

On March 23, 2014 these countries released more than 100,000 acre-feet of water into the delta below the Morelos Dam.  This area is along the Colorado River on the U.S.-Mexico border. 

On May 15, 2014, the river finally met the sea. (read more)

El Niño Tracker - April 2015

Friday, April 17, 2015
Ben McMahan

This was originally published in the April 2015 Southwest Climate Outlook

Strong signals in early 2014 stalled, delaying El Niño’s onset until last month, when ocean-atmosphere coupling and an additional Kelvin wave indicated more favorable conditions. Despite this late start, El Niño continued for a second consecutive month. Recent increases in sea surface temperature (SST) anomalies (Fig.1 - 2) and ongoing convective activity associated with El Niño-favorable conditions indicate we might be witnessing a two-year El Niño event. These forecasts rely on projections during a time of increasing uncertainty, and the so-called “spring predictability barrier” continues to make it difficult to anticipate how seasonal changes will help or hinder El Niño. (read more)

Southwest Climate Outlook April 2015 - Climate Summary

Thursday, April 16, 2015
Ben McMahan

Precipitation: In the past 30 days, most of the southwestern U.S. received below-average precipitation (Fig. 1). The winter wet season is wrapping up, and instead of above-average precipitation (as many of the El Niño influenced seasonal forecasts suggested), water year observations since October 1 show below-average precipitation across much of Arizona and portions of New Mexico. The situation is direr in other western regions, with California, the Pacific Northwest, and the Intermountain West recording significantly below-average winter precipitation (Fig. 2). (read more)

Spring Signals the Start of Wildfire Season for the Southwest

Wednesday, April 15, 2015
Michael Crimmins

A version of this post was also published in the April 2015 Southwest Climate Outlook

Flowers are blooming and trees have sprouted green leaves, signs that spring is in full swing across the Southwest and that, despite a verdant desert, wildfire season is upon us. The outlook for this wildfire season forecasts near-average wildfire activity for much of Arizona and New Mexico.