scholarly journals Diurnal warming in the tropical Pacific and its interannual variability

2005 ◽  
Vol 32 (21) ◽  
Author(s):  
Carol Anne Clayson ◽  
Derrick Weitlich
Keyword(s):  
Interannual Variability ◽  
Tropical Pacific ◽  
Diurnal Warming ◽  
The Tropical Pacific

Interannual variability simulated in the Tropical Pacific

1997 ◽  
pp. 395-408
Author(s):  
Jorge Macías ◽  
David Stephenson ◽  
Laurent Terray ◽  
Sophie Belamari
Keyword(s):  
Interannual Variability ◽  
Tropical Pacific ◽  
The Tropical Pacific

scholarly journals Weakened Interannual Variability in the Tropical Pacific Ocean since 2000

2013 ◽  
Vol 26 (8) ◽  
pp. 2601-2613 ◽  
Author(s):  
Zeng-Zhen Hu ◽  
Arun Kumar ◽  
Hong-Li Ren ◽  
Hui Wang ◽  
Michelle L’Heureux ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Interannual Variability ◽  
Southern Oscillation ◽  
Walker Circulation ◽  
Tropical Pacific ◽  
Warm Water ◽  
Water Volume ◽  
Tropical Pacific Ocean ◽  
Trade Winds ◽  
The Tropical Pacific

Abstract An interdecadal shift in the variability and mean state of the tropical Pacific Ocean is investigated within the context of changes in El Niño–Southern Oscillation (ENSO). Compared with 1979–99, the interannual variability in the tropical Pacific was significantly weaker in 2000–11, and this shift can be seen by coherent changes in both the tropical atmosphere and ocean. For example, the equatorial thermocline tilt became steeper during 2000–11, which was consistent with positive (negative) sea surface temperature anomalies, increased (decreased) precipitation, and enhanced (suppressed) convection in the western (central and eastern) tropical Pacific, which reflected an intensification of the Walker circulation. The combination of a steeper thermocline slope with stronger surface trade winds is proposed to have hampered the eastward migration of the warm water along the equatorial Pacific. As a consequence, the variability of the warm water volume was reduced and thus ENSO amplitude also decreased. Sensitivity experiments with the Zebiak–Cane model confirm the link between thermocline slope, wind stress, and the amplitude of ENSO.

scholarly journals Global Air–Sea CO2 Flux in 22 CMIP5 Models: Multiyear Mean and Interannual Variability*

2016 ◽  
Vol 29 (7) ◽  
pp. 2407-2431 ◽  
Author(s):  
Fang Dong ◽  
Yangchun Li ◽  
Bin Wang ◽  
Wenyu Huang ◽  
Yanyan Shi ◽  
...  
Keyword(s):  
Interannual Variability ◽  
Dissolved Inorganic Carbon ◽  
Southern Oscillation ◽  
Dominant Role ◽  
Co2 Flux ◽  
Tropical Pacific ◽  
Cmip5 Models ◽  
Period Range ◽  
Enso Events ◽  
The Tropical Pacific

Abstract To assess the capability of the latest Earth system models (ESMs) in representing historical global air–sea CO2 flux, 22 models from phase 5 of the Coupled Model Intercomparision Project (CMIP5) are analyzed, with a focus on the spatial distribution of multiyear mean and interannual variability. Results show that the global distribution of air–sea CO2 flux is reasonable in most of the models and that the main differences between models and observationally based results exist in regions with strong vertical movement. The annual mean flux in the 18-member multimodel ensemble (MME; four models were excluded because of their poor performances) mean during 1996–2004 is 1.95 Pg C yr−1 (1 Pg = 1015 g; positive values mean into the ocean), and all but one model describe the rapid increasing trend of air–sea CO2 flux observed during 1960–2000. The first mode of the global air–sea CO2 flux variability during 1870–2000 in six of the models represents the El Niño–Southern Oscillation (ENSO) mode. The remaining 12 models fail to represent this important character for the following reasons: in five models, the tropical Pacific does not play a dominant role in the interannual variability of global air–sea CO2 flux because of stronger interannual variability in the Southern Ocean; two models poorly represent the interannual fluctuation of dissolved inorganic carbon (DIC) in the surface ocean of the tropical Pacific; and four models have shorter periods of the air–sea CO2 flux, which are out of the period range of ENSO events.

scholarly journals Natural variability in the surface ocean carbonate ion concentration

2015 ◽  
Vol 12 (21) ◽  
pp. 6321-6335 ◽  
Author(s):  
N. S. Lovenduski ◽  
M. C. Long ◽  
K. Lindsay
Keyword(s):  
Interannual Variability ◽  
North Atlantic ◽  
North Pacific ◽  
Tropical Pacific ◽  
Ion Concentration ◽  
Saturation State ◽  
Surface Ocean ◽  
The North ◽  
Carbonate Ion ◽  
The Tropical Pacific

Abstract. We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32−] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite) are already or nearly detectable at the sustained, open-ocean time series sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32−] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC) in association with El Niño–Southern Oscillation. In the North Pacific, surface [CO32−] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20–30-year periods. North Atlantic [CO32−] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially and temporally sparse observations.

scholarly journals Early and mid-Holocene climate in the tropical Pacific: seasonal cycle and interannual variability induced by insolation changes

2012 ◽  
Vol 8 (1) ◽  
pp. 505-555 ◽  
Author(s):  
Y. Luan ◽  
P. Braconnot ◽  
Y. Yu ◽  
W. Zheng ◽  
O. Marti
Keyword(s):  
Interannual Variability ◽  
Radiative Forcing ◽  
Seasonal Cycle ◽  
Tropical Pacific ◽  
Shortwave Radiation ◽  
Orbital Parameter ◽  
Sensitivity Experiment ◽  
The Mean ◽  
Mean Climate ◽  
The Tropical Pacific

Abstract. Using a coupled atmosphere-ocean model we analyze the responses of the mean climate and interannual variations in the tropical Pacific to the changes in insolation during the early and middle Holocene, for which only the variations of Earth's orbital configuration are considered. Comparison of the early and mid-Holocene with pre-industrial climate shows that both the mean climate and the characteristics of the interannual variability are altered by the changes in insolation. In particular, there is a decrease of the annual mean SST, which is characterized by a "U" shape across the tropical Pacific. The changes of the SST seasonal cycle are consistent with the changes in insolation, with the SST amplitudes weakening in the tropics. However, the larger changes in seasonality are found in the eastern Pacific, where thermodynamics and dynamical processes strengthen the SST response. The cloud radiative forcing largely reduces the shortwave radiation in the western tropical Pacific in winter causing a zonally asymmetric heat flux response. Simulations also show that ENSO strengthens across the Holocene, as suggested by coral data or lake sediments. The role of the obliquity is examined by a sensitivity experiment and we find that the obliquity change affects the seasonal displacement of ITCZ related to strength of SST meridional gradients. However, the obliquity change has little effect on SST seasonal cycle and interannual variability in eastern tropical Pacific. The precession of the orbital parameter is more important in effecting the tropical climate.

scholarly journals Natural variability in the surface ocean carbonate ion concentration

2015 ◽  
Vol 12 (15) ◽  
pp. 13123-13157
Author(s):  
N. S. Lovenduski ◽  
M. C. Long ◽  
K. Lindsay
Keyword(s):  
Interannual Variability ◽  
North Atlantic ◽  
North Pacific ◽  
Tropical Pacific ◽  
Ion Concentration ◽  
Saturation State ◽  
Surface Ocean ◽  
The North ◽  
Carbonate Ion ◽  
The Tropical Pacific

Abstract. We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a long control simulation with a fully-coupled Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32−] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite) are already or nearly detectable at the sustained, open-ocean timeseries sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32−] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC) in association with El Niño–Southern Oscillation. In the North Pacific, surface [CO32−] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20–30 year periods. North Atlantic [CO32−] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends calculated from spatially- and temporally-sparse observations.

Sign in / Sign up

Export Citation Format

Share Document