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Enzel, Y, Cayan DR, Anderson RY, Wells SG.  1989.  Atmospheric circulation during Holocene lake stands in the Mojave Desert: evidence of regional climate change. Nature. 341:44-47.   10.1038/341044a0   AbstractWebsite

IT is commonly thought that the climate conditions that supported lakes over a period of years in the Mojave Desert in southern California, only existed before 8,000 yr BP and that the environment has been arid since1,2. Here we look at a drill core in the Silver Lake playa at the terminus of the Mojave River and find Holocene lake deposits which indicate that shallow lakes existed for at least a few decades. These deposits were radiocarbon dated at 3620 ±70 and 390 ± 90 yr BP, corresponding to the early Neo-glacial and the 'little ice age' respectively3. To identify the conditions necessary to produce these Holocene lake events we have examined the modern climate and hydrological patterns that produce ephemeral lakes in this usually arid watershed. Available data indicate that there is a link between anomalous winter atmospheric conditions over the North Pacific and Mojave River floods that produced ephemeral lakes in the Silver Lake playa and that the Mojave River filters out small to medium floods and allows only the extreme floods to reach the terminal playa and leave a record of the anomalous conditions. We suggest that the late Holocene lakes may have resulted from persistent similar atmospheric circulation patterns and winter floods.

Ely, LL, Enzel Y, Cayan DR.  1994.  Anomalous North Pacific atmospheric circulation and large winter floods in the Southwestern United States. Journal of Climate. 7:977-987.   10.1175/1520-0442(1994)007<0977:anpaca>2.0.co;2   AbstractWebsite

Specific anomalous atmospheric circulation conditions over the North Pacific are conducive to the occurrence of the largest winter floods (greater-than-or-equal-to 10-yr return period) on rivers in six hydroclimatic subregions of Arizona and southern Utah, Nevada, and California. Composite maps of anomalies in daily 700-mb heights indicate that floods in all of the subregions are associated with a low pressure anomaly off the California coast and a high-pressure anomaly in the vicinity of either Alaska or the Aleutian Islands. Of these two major circulation features, the presence of the low is the controlling factor in determining whether large floods will occur. Shifts in the locations of the low and high pressure anomalies over the North Pacific appear to control which subregions experience floods, with high-elevation topographic features and proximity to air masses forming a major influence over the specific atmospheric circulation conditions that generate large floods in each hydroclimatic region. Concerning the interannual variability of flooding in the Southwest, there is an increased frequency of large winter floods during multiple-year periods dominated by negative SOI and a virtual absence of large floods during the intervening periods. This suggests that global-scale climatic anomalies exert a strong influence on the occurrence of severe regional winter floods.

Ely, LL, Enzel Y, Baker VR, Cayan DR.  1993.  A 5000-year record of extreme floods and climate change in the Southwestern United States. Science. 262:410-412.   10.1126/science.262.5132.410   AbstractWebsite

A 5000-year regional paleoflood chronology, based on flood deposits from 19 rivers in Arizona and Utah, reveals that the largest floods in the region cluster into distinct time intervals that coincide with periods of cool, moist climate and frequent El Nino events. The floods were most numerous from 4800 to 3600 years before present (B.P.), around 1000 years B.P., and after 500 years B.P., but decreased markedly from 3600 to 2200 and 800 to 600 years B.P. Analogous modern floods are associated with a specific set of anomalous atmospheric circulation conditions that were probably more prevalent during past flood epochs.