|
|
Imagine a stream of water thousands of kilometers long and as wide as the distance between New York City and Washington, D. C., flowing toward you at 30 miles per hour. No, this is not some hypothetical physics problem—it is a real river, carrying more water than 7–15 Mississippi Rivers combined. But it is not on land. It's a river of water vapor in the atmosphere. Atmospheric rivers (ARs) are narrow corridors of water vapor transport in the lower atmosphere that traverse long swaths of the Earth's surface as they bind together the atmospheric water cycle (Figure 1). The characteristic (indeed defining) dimensions of these ARs are (1) integrated water vapor (IWV) concentrations such that if all the vapor in the...
|
The influence of the El Nin??o-Southern Oscillation (ENSO) phenomenon on flooding in California coastal streams is investigated by analyzing the annual peak floods recorded at 38 gauging stations. The state of ENSO prior to and during flooding is characterized by the multivariate ENSO index (MEI), where MFI < -0.5 is defined as the La Nin??a phase and MEI > 0.5 as the El Nin??o phase. Flood magnitude in all 20 streams located south of 35??N has a significant positive correlation (r = 0.3 to 0.6), whereas in 3 of the 4 streams located north of 41??N flood magnitude has a significant negative correlation (r = -0.3 to -0.4), with MEI from -2.2 to + 3.2. Correlations with MEI are uniformly weak and insignificant, however,...
|
|
