Boulder researchers at the University of Colorado and the National Oceanic and Atmospheric Administration anticipate an emerging El Ni帽o event may reduce the severity of drought conditions in the Southwest United States this summer.
The announcement was made this week by researchers at the Climate Diagnostics Center, run jointly by CU-Boulder and NOAA through the Cooperative Institute for Research in Environmental Sciences. CIRES is headquartered on the CU-Boulder campus.
El Ni帽o is the periodic warming of water in the tropical Pacific Ocean that temporarily influences climate throughout the world. Scientists said earlier last week that the United States could start feeling the impacts of the developing El Ni帽o as early as mid-summer 2002. The scientists cautioned that the strength of the expected El Ni帽o is still unknown.听
"If a full-blown El Ni帽o occurs it will be good news for the Southwest, since El Ni帽o typically brings wetter than normal conditions for that region," said Martyn Clark, a CIRES researcher and project leader of the Western Water Assessment, or WWA.
River basins throughout the Southwest are dangerously short of water. Accumulated precipitation in the Gila River basin in Arizona, for example, is only 26 percent of normal.听
The Salt River basin in Arizona is at 30 percent of normal, the Escalante River in Utah is at 46 percent, the Upper Rio Grande basin in Colorado is at 45 percent and the San Juan River headwaters in southwestern Colorado are at 46 percent of normal.
"In eight of the last 10 El Ni帽os, the Southwest has experienced higher than normal annual runoff," Clark said. "Of course, climate prediction is an uncertain business, but I like the odds."听
The same odds also suggest a drying trend in the Pacific Northwest, which has rebounded significantly from drought conditions two years ago, he said.
Until increased precipitation materializes in the Southwest, the wildfire danger in the region will continue to be high, and already low reservoirs will be hard pressed to satisfy thirsty populations, said Clark.
"The four fastest growing states in the nation -- Nevada, Arizona, Colorado, and Utah -- are all experiencing drought," said Doug Kenney, a WWA researcher based at the Natural Resources Law Center at CU-Boulder. "Many new residents have never experienced anything like this."