HR: 1340h
AN: A23B-0795 [Abstracts]
TI: Stationarity of the ocean component of the climate signal
AU: * Tokmakian, R
EM: rtt@nps.edu
AF: Dept. of Oceanography, Naval Postgraduate School, 833 Dyer Rd, Bldg 232, Rm 328, Monterey, CA
93943-5122
United States
AB:
Empirical orthogal functions (EOFs) have been used extensively in
recent years to explore the primary spatial and temporal distribution of the ocean's variability on both basin and global
scales. Such
empirical segmentation of time series are sometimes used as a way
to extend time series back in time. This paper using
both EOFs and Cyclic EOFs [Kim, et al. 1999] explores the spatial
distribution of the ocean's variability and its relationship to the
dynamic climate signal and how the primary signal patterns are
modified in time. Using a relatively high resolution ocean model (0.2 degrees) forced with a 40+ year time series of
realistic NCEP atmospheric fluxes, the stationarity of the interannual and longer sea surface height and upper ocean
temperature signals are quantified and related to the forces applied at the ocean's surface. (Stationarity: A stationary
process has the property that the mean, variance and autocorrelation structure do not change over time. For this purpose, any
long term trend is removed.) With the model
as an example time series, the stationarity of the ocean's upper
ocean quantities is further examined through the use of satellite
measurements of the ocean. While a percentage of the ocean's variability is relatively stationary, a significant proportion
is not. Regional causes of the non-stationarity in the signal are explored.
DE: 3337 Numerical modeling and data assimilation
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
DE: 3360 Remote sensing
DE: 1620 Climate dynamics (3309)
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting