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Shu?WuEmail author Zhengyu?Liu Rong?Zhang Thomas?L.?Delworth 《Journal of Oceanography》2011,67(1):27-35
We studied the relationship between the dominant patterns of sea surface temperature (SST) variability in the North Pacific
and the North Atlantic. The patterns are known as the Pacific Decadal Oscillation (PDO) and the Atlantic Multi-decadal Oscillation
(AMO). In the analysis we used two different observational data sets for SST. Due to the high degree of serial correlation
in the PDO and AMO time series, various tests were carried out to assess the significance of the correlations. The results
demonstrated that the correlations are significant when the PDO leads the AMO by 1 year and when the AMO leads the PDO by
11–12 years. The possible physical processes involved are discussed, along with their potential implication for decadal prediction. 相似文献
944.
Short-term wave design approach of marine structures, using nonlinear time domain simulations, is a design procedure that is recognized by various modern standard codes. One of the most challenging points of this approach is the evaluation of the characteristic extreme values for response parameters used in the design check equations. The most straightforward and recommended way to evaluate a response characteristic value is by fitting an extreme value probability distribution to the N-sample of extreme values extracted from N independent time domain simulations with duration equal to the short-term period indicated by the code, which is usually taken as 3 h. However, this procedure would not be practical for some types of marine structures, such as risers and mooring lines, under numerous design load cases and demanding huge finite element models. A more feasible approach would be to assess the response extreme value distribution using only a single short-term time domain simulation with duration shorter than 3 h. But reduced time simulations always introduce some additional statistical uncertainty into the extreme values estimates. This paper discusses a workable way of properly taking into account the statistical uncertainty associated with the simulation length in the assessment of a characteristic short-term extreme response value based on a single time series. 相似文献
945.
V. V. Zuev S. L. Bondarenko N. E. Zueva 《Izvestiya Atmospheric and Oceanic Physics》2011,47(9):1032-1038
The response of the total ozone (TO) at subarctic latitudes to volcanic eruptions, products of which were injected into the
stratosphere, is analyzed. It is established that the behavior of the series of average annual TO values according to the
TOMS, SCIAMACHY, and GOME space equipment data averaged for 55°–65° N latitudes agrees with the activity of explosive volcanic
eruptions. The series of the TO satellite monitoring instrumental data are extended by 200 years into the past using a reconstruction
from the dendro-chronologic data. An analysis of the series of TO reconstructed values indicates that volcanogenic perturbations
of the subarctic ozonosphere initiate long-term negative TO deviations. In this case, the TO negative deviation depth depends
on the frequency of the ozonosphere volcanogenic perturbations and the phase of quasiperiodic oscillation cycles rather than
on the strength of a single volcanic explosion. 相似文献
946.
M. B. Gokhberg G. M. Steblov S. L. Shalimov V. A. Veis E. A. Grekhova 《Izvestiya Atmospheric and Oceanic Physics》2011,47(8):929-940
Using available Russian and international Global Positioning System (GPS) network data, we studied the ionospheric response
to the M = 8.9 submarine earthquake of March 11, 2011, on the northeastern coast of Honshu Island, Japan, both near and far (about
2000 km away) from the epicenter. In the region over the epicenter, 8.7 min after the event, we detected a characteristic
signal of the total electron content (TEC) variations consisting of compression and rarefaction phases and a linear transition
zone in between, i.e., in the form of an N-type wave with a steep leading front indicating a rapid uplift of the water surface and, correspondingly, the bottom of the
ocean. The shape of the signal can be used for early tsunami warning; i.e., it may indicate the tsunamigenic character of
a submarine earthquake. We monitored the subsequent evolution of the ionospheric response as far as 2000 km from the epicenter.
It was shown that, besides the wellknown ionospheric N-type wave response to the earthquake, there is also a response in the form of an inverted N-wave, both nearby and far from the epicenter. We detected two more types of ionospheric responses far from the epicenter:
a solitary-like wave and an internal gravity wave (IGW). The detected signals have been interpreted. 相似文献
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