Abstract:
[1] A study of the influences of interdecadal and
interannual oceanic-atmospheric influences on April 1
Snow-Water Equivalent (SWE) in the western U.S. is
presented. SWE data was identified at 323 Natural
Resources Conservation Service (NRCS) SNOTEL
(SNOwpack TELemetrysites) stations for the period of
1961 to 2004 and for 121 SNOTEL stations for the period
1941 to 2004. The phases (cold/negative or warm/positive)
of Pacific Ocean [El Nino -Southern Oscillation (ENSO)
and Pacific Decadal Oscillation (PDO)] and Atlantic Ocean
[Atlantic Multidecadal Oscillation (AMO) and North
Atlantic Oscillation (NAO)] oceanic-atmospheric
influences were identified for the year prior to the SWE
data set. Statistical significance testing of SWE data set,
based on the interdecadal and interannual oceanic atmospheric
phase (warm/positive or cold/negative) was
performed by applying the nonparametric rank-sum test.
The results show that in addition to the well established
ENSO signal in the northwest, the PDO and AMO influence
SWE variability. Additionally, the coupled effects of the
oceanic-atmospheric influences were evaluated on the basis
of the long-term phase (cold/negative or warm/positive) of
the interdecadal (PDO, AMO, NAO) influences and the
interannual ENSO. Finally, the coupled effects of the
oceanic-atmospheric influences were evaluated on the basis
of the long-term phase (cold/negative or warm/positive) of
the interdecadal (AMO, PDO, NAO) phenomena. Regions
in the west were identified that responded to the interdecadal/
decadal climatic coupling. By utilizing the April 1 SWE
and the long lead-time approach for the oceanic atmospheric
variables, useful information can be
provided to snow forecasters and water managers.
Citation: Hunter, T., G. Tootle, and T. Piechota (2006),
Oceanic-atmospheric variability and western U.S. snowfall,
Geophys. Res. Lett., 33, L13706, doi:10.1029/2006GL026600.
