scholarly journals On the relationship between the interannual and decadal SST variability in the North Pacific and tropical Pacific Ocean

2003 ◽  
Vol 108 (D11) ◽  
Author(s):  
Sang-Wook Yeh
2012 ◽  
Vol 117 (D15) ◽  
pp. n/a-n/a ◽  
Author(s):  
Sae-Rim Yeo ◽  
Kwang-Yul Kim ◽  
Sang-Wook Yeh ◽  
WonMoo Kim

2020 ◽  
Vol 17 (3) ◽  
pp. 813-831
Author(s):  
Lothar Stramma ◽  
Sunke Schmidtko ◽  
Steven J. Bograd ◽  
Tsuneo Ono ◽  
Tetjana Ross ◽  
...  

Abstract. A strong oxygen-deficient layer is located in the upper layers of the tropical Pacific Ocean and deeper in the North Pacific. Processes related to climate change (upper-ocean warming, reduced ventilation) are expected to change ocean oxygen and nutrient inventories. In most ocean basins, a decrease in oxygen (“deoxygenation”) and an increase in nutrients have been observed in subsurface layers. Deoxygenation trends are not linear and there could be multiple influences on oxygen and nutrient trends and variability. Here oxygen and nutrient time series since 1950 in the Pacific Ocean were investigated at 50 to 300 m depth, as this layer provides critical pelagic habitat for biological communities. In addition to trends related to ocean warming the oxygen and nutrient trends show a strong influence of the Pacific Decadal Oscillation (PDO) in the tropical and the eastern Pacific, and the North Pacific Gyre Oscillation (NPGO) in particular in the North Pacific. In the Oyashio Region the PDO, the NPGO, the North Pacific Index (NPI) and an 18.6-year nodal tidal cycle overlay the long-term trend. In most eastern Pacific regions oxygen increases and nutrients decrease in the 50 to 300 m layer during the negative PDO phase, with opposite trends during the positive PDO phase. The PDO index encapsulates the major mode of sea surface temperature variability in the Pacific, and oxygen and nutrients trends throughout the basin can be described in the context of the PDO phases. El Niño and La Niña years often influence the oxygen and nutrient distribution during the event in the eastern tropical Pacific but do not have a multi-year influence on the trends.


2021 ◽  
pp. 1-68
Author(s):  
Jing Ming ◽  
Jianqi Sun

AbstractThis study investigates the relationship between the central tropical Pacific (CTP) sea surface temperature (SST) and the surface air temperature (SAT) variability un-related to canonical El Niño-Southern Oscillation (ENSO) over mid-to-high latitude Eurasia during boreal summers over the past half-century. The results show that their relationship experienced a decadal shift around the early 1980s. Before the early 1980s, the Eurasian SAT-CTP SST connection was weak; after that time, the relationship became stronger, and the SAT anomalies exhibited a significant wave-like pattern over Eurasia. Such a decadal change in the Eurasian SAT-CTP SST relationship could be attributed to decadal changes in the mean state and variability of CTP SST. The warmer mean state and enhanced SST variability after the early 1980s reinforced the convective activities over the tropical Pacific, leading to significantly anomalous divergence/convergence and Rossby wave sources over the North Pacific. This outcome further excited the wave train propagating along the Northern Hemisphere zonal jet stream to northern Eurasia and then affected the surface heat fluxes and atmospheric circulations over the region, resulting in wave-like SATs over Eurasia. However, during the period before the early 1980s, the CTP SST had a weak impact on the North Pacific atmospheric circulation and was consequently not able to excite the wave train pattern to impact the Eurasian atmospheric circulation and SATs. The physical processes linking the CTP SST and Eurasian SAT are further confirmed by numerical simulations. The results of this study are valuable to understanding the variability of summer Eurasian SATs.


2007 ◽  
Vol 20 (11) ◽  
pp. 2581-2601 ◽  
Author(s):  
Lixin Wu ◽  
Chun Li

Abstract In this paper, global climatic response to the North Pacific oceanic warming is investigated in a series of coupled ocean–atmosphere modeling experiments. In the model, an idealized heating is imposed over the North Pacific Ocean, while the ocean and atmosphere remain fully coupled both locally and elsewhere. The model explicitly demonstrates that the North Pacific oceanic warming can force a significant change of the atmospheric circulation with a strong seasonal dependence. The seasonal marching of the atmospheric response over the North Pacific is characterized by a quasi-baratropic warm ridge in early winter, a transition to a quasi-baratropic warm trough in late winter, and then to a baroclinic response in summer with a trough and ridge, respectively, in the lower and upper troposphere. The North Pacific warming also forces a significant remote response over the tropical Pacific. In winter, the tropical Pacific response is characterized by a nearly uniform warming coupled with anomalous southerly cross-equatorial winds, while in summer it is dominated by an enhanced zonal SST gradient and anomalous equatorial easterlies. The tropical warming tends to be associated with a reduction of the upper-ocean meridional overturning circulation and equatorial ocean dynamics associated with a reduction of the Hadley circulation and the surface coupled wind–evaporation–SST feedback. The resulting tropical warming can further intensify the seasonal marching of the North Pacific atmospheric response. The global impacts of the North Pacific warming are also discussed.


2019 ◽  
Author(s):  
Lothar Stramma ◽  
Sunke Schmidtko ◽  
Steven J. Bograd ◽  
Tsuneo Ono ◽  
Tetjana Ross ◽  
...  

Abstract. A strong oxygen deficient layer is located in the upper layer of the tropical Pacific Ocean and at deeper depths in the North Pacific. Processes related to climate change (upper ocean warming, reduced ventilation) are expected to change ocean oxygen and nutrient inventories. In most ocean basins, a decrease in oxygen (‘deoxygenation’) and an increase of nutrients has been observed in subsurface layers. Deoxygenation trends are not linear and there could be other influences on oxygen and nutrient trends and variability. Here oxygen and nutrient time series since 1950 in the Pacific Ocean were investigated at 50 to 300 m depth, as this layer provides critical pelagic habitat for biological communities. In addition to trends related to ocean warming the oxygen and nutrient trends show a strong influence of the Pacific Decadal Oscillation (PDO) in the tropical and the eastern Pacific, and the North Pacific Gyre Oscillation (NPGO) especially in the North Pacific. In the Oyashio Region the PDO, the NPGO, the North Pacific Index (NPI) and a 18.6 year nodal tidal cycle overlay the long-term trend. In most regions oxygen increases and nutrients decrease in the 50 to 300 m layer during the negative PDO phase, with opposite trends during the positive PDO phase. The PDO index encapsulates the major mode of surface temperature variability in the Pacific and oxygen and nutrients trends throughout the basin can be described in the context of the PDO phases. An influence of the subtropical-tropical cell in the tropical Pacific cannot be proven with the available data. El Niño and La Niña years often influence the oxygen and nutrient distribution during the event in the eastern tropical Pacific, but do not have a multi-year influence on the trends.


2021 ◽  
Author(s):  
Matthew H. Rogers ◽  
Jason Furtado ◽  
Bruce Anderson

Abstract Persistent, multi-year shifts in atmospheric circulations and their associated influence on regional climates have profound impacts on physical, biological, and socioeconomic systems. The Pacific Decadal Precession (PDP), an atmospheric mode of variability consisting of a lower tropospheric height dipole which rotates counterclockwise over several years in the North Pacific, describes a series of such shifts in atmospheric circulations. One phase of the PDP, the north-south (N-S) phase, is hypothesized to be partially driven by central tropical Pacific (CP) sea surface temperature (SST) variability, but robust assessment of this dynamical connection in climate models remains to be done. In this study, we investigate this hypothesis with analyses in both reanalysis and selected models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) archive. We show that the emergence of the N-S phase is both related to and influenced by tropical Pacific decadal SST variability, specifically variability associated with CP El Niño-Southern Oscillation (ENSO) events. When examining the CMIP6 model output, we find that most models cannot recover the characteristic cyclonic precession of the dipoles of the PDP, instead featuring only amplitude and sign changes of the N-S phase, Moreover, the models do not replicate the dynamical connections between the tropical Pacific and this North Pacific mode. Our results suggest that primary reasons for this inconsistency are that models inaccurately simulate both the SST pattern associated with the PDP, shared low-frequency power associated with CP ENSO events, and incorrect Rossby wavetrains emanating from the tropical Pacific into the North Pacific on quasi-decadal timescales. Taken together, our analyses offer another benchmark by which to test the fidelity of the climate model simulations in capturing Pacific decadal climate variability in order to improve decadal-to-centennial climate projections.


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