doi:10.1007/s00376-015-5113-8

Behrenfeld M. J., 2010: Abandoning Sverdrup's critical depth hypothesis on phytoplankton blooms. Ecology, 91( 4), 977- 989.10.1890/09-1207.1

20462113

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http%3A%2F%2Fmed.wanfangdata.com.cn%2FPaper%2FDetail%2FPeriodicalPaper_PM20462113

refpaperuri:(41c057236e3f33f8516d8c08279980fd)

http://med.wanfangdata.com.cn/Paper/Detail/PeriodicalPaper_PM20462113The Critical Depth Hypothesis formalized by Sverdrup in 1953 posits that vernal phytoplankton blooms occur when surface mixing shoals to a depth shallower than a critical depth horizon defining the point where phytoplankton growth exceeds losses. This hypothesis has since served as a cornerstone in plankton ecology and re04ects the very common assumption that blooms are caused by enhanced growth rates in response to improved light, temperature, and strati03cation conditions, not simply correlated with them. Here, a nine-year satellite record of phytoplankton biomass in the subarctic Atlantic is used to reevaluate seasonal plankton dynamics. Results show that (1) bloom initiation occurs in the winter when mixed layer depths are maximum, not in the spring, (2) coupling between phytoplankton growth (l) and losses increases during spring strati03cation, rather than decreases, (3) maxima in net population growth rates (r) are as likely to occur in midwinter as in spring, and (4 ) r is generally inversely related to l. These results are incompatible with the Critical Depth Hypothesis as a functional framework for understanding bloom dynamics. In its place, a ‘‘Dilution–Recoupling Hypothesis’’ is described that focuses on the balance between phytoplankton growth and grazing, and the seasonally varying physical processes in04uencing this balance. This revised view derives from fundamental concepts applied during 03eld dilution experiments, builds upon earlier modeling results, and is compatible with observed phytoplankton blooms in the absence of spring mixed layer shoaling.

Boss E., M. Behrenfeld, 2010: In situ evaluation of the initiation of the North Atlantic phytoplankton bloom. Geophys. Res. Lett., 37,L18603, doi: 10.1029/2010GL044174.10.1029/2010GL044174

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2010GL044174%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1029/2010GL044174/citedbyTwo years of continuous physical and optical measurements from a profiling float in the western subarctic North Atlantic are used to analyze seasonal phytoplankton dynamics. The observed annual cycle challenges the traditional view that initiation of spring accumulations of phytoplankton in the upper water column requires a critical stratification threshold (known as the 'Gran effect' or the 'S...

Chiswell S. M., 2011: Annual cycles and spring blooms in phytoplankton: Don't abandon Sverdrup completely. Marine Ecology Progress Series, 443, 39- 50.10.3354/meps09453

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http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F235289594_Annual_cycles_and_spring_blooms_in_phytoplankton_don%27t_abandon_Sverdrup_completely

http://www.researchgate.net/publication/235289594_Annual_cycles_and_spring_blooms_in_phytoplankton_don't_abandon_Sverdrup_completelyThe critical-depth model for the onset of the spring phytoplankton bloom in the North Atlantic has recently been called into question by several researchers. The critical-depth model considers that the spring bloom starts when the mixed layer shoals to become shallower than a critical depth. Satellite and in situ measurements of chlorophyll are used here to show that the critical-depth model is indeed flawed. It is shown that the critical-depth model does not apply in the spring because the basic assumption of an upper layer that is well-mixed in plankton is not met. Instead, the spring bloom forms in shallow near-surface layers that deepen with the onset of thermal stratification. A stratification-onset model for the annual cycle in plankton is proposed that adheres to the conventional idea that the spring bloom represents a change from a deep-mixed regime to a shallow light-driven regime, but where the upper layers are not well mixed in plankton in spring and so the critical-depth model does not apply. Ironically, perhaps, the critical-depth model applies in the autumn and winter when plankton are well-mixed to the seasonal thermocline, so that the critical-depth model can be used to determine whether net winter production is positive or negative.

Chiswell S. M., P. H. R. Calil, and P. W. Boyd, 2015: Spring blooms and annual cycles of phytoplankton: a unified perspective. Journal of Plankton Research, 37( 3), 500- 508.10.1093/plankt/fbv021

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http%3A%2F%2Fplankt.oxfordjournals.org%2Fcontent%2F37%2F3%2F500.short

http://plankt.oxfordjournals.org/content/37/3/500.shortABSTRACT Several hypotheses exist that describe phytoplankton spring blooms in temperate and subpolar oceans: the critical depth, shoaling mixed layer (ML), critical turbulence, onset of stratification and disturbance-recovery hypotheses. These theories appear to be mutually exclusive and none of them describe the annual cycle of phytoplankton biomass. Here, we present a model of the annual cycle in phytoplankton that recognizes that phytoplankton are not always mixed throughout the so-called ML, and that it is important to distinguish between the surface biomass and depth-integrated phytoplankton. Once these important distinctions are made, the annual cycles and blooms in surface and depth-integrated phytoplankton can be described straightforwardly in terms of the physical drivers and biotic responses.

Gill A. E., 1982: Atmosphere-Ocean Dynamics.Academic press, 662 pp.

Hashioka T., T. T. Sakamoto, and Y. Yamanaka, 2009: Potential impact of global warming on north Pacific spring blooms projected by an eddy-permitting 3-D ocean ecosystem model. Geophys. Res. Lett., 36, L20604.10.1029/2009GL038912

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2009GL038912%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1029/2009GL038912/citedbyUsing an eddy-permitting ecosystem model with a projected physical environment from a high-resolution climate model, we explored the potential impact of global warming on spring blooms in the western North Pacific. We focused on statistically significant signals compared with natural variability. Considering 2 CO2 conditions, maximum biomass during the spring bloom is found to occur 10 to 20 d...

Held I. M., M. Winton, K. Takahashi, T. Delworth, F. R. Zeng, and G. K. Vallis, 2010: Probing the fast and slow components of global warming by returning abruptly to preindustrial forcing. J. Climate, 23( 9), 2418- 2427.10.1175/2009JCLI3466.1

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http%3A%2F%2Fwww.cabdirect.org%2Fabstracts%2F20103193982.html

refpaperuri:(4e9122e2f4ebe1b6b817388f040a8cf1)

http://www.cabdirect.org/abstracts/20103193982.htmlAbstract The fast and slow components of global warming in a comprehensive climate model are isolated by examining the response to an instantaneous return to preindustrial forcing. The response is characterized by an initial fast exponential decay with an e -folding time smaller than 5 yr, leaving behind a remnant that evolves more slowly. The slow component is estimated to be small at present, as measured by the global mean near-surface air temperature, and, in the model examined, grows to 0.4°C by 2100 in the A1B scenario from the Special Report on Emissions Scenarios (SRES), and then to 1.4°C by 2300 if one holds radiative forcing fixed after 2100. The dominance of the fast component at present is supported by examining the response to an instantaneous doubling of CO 2 and by the excellent fit to the model’s ensemble mean twentieth-century evolution with a simple one-box model with no long times scales.

Huisman J. E. F., P. van Oostveen, and F. J. Weissing, 1999: Critical depth and critical turbulence: Two different mechanisms for the development of phytoplankton blooms. Limnology and Oceanography, 44( 7), 1781- 1787.10.4319/lo.1999.44.7.1781

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.4319%2Flo.1999.44.7.1781%2Fpdf

http://onlinelibrary.wiley.com/doi/10.4319/lo.1999.44.7.1781/pdfA turbulent diffusion model shows that there are two different mechanisms for the development of phytoplankton blooms. One of these mechanisms works in well-mixed environments and corresponds to the classical critical depth theory. The other mechanism is based on the rate of turbulent mixing. If turbulent mixing is less than a critical turbulence, phytoplankton growth rates exceed the vertical mixing rates, and a bloom develops irrespective of the depth of the upper water layer. These results demonstrate that phytoplankton blooms can develop in the absence of vertical water-column stratification.

Kara A. B., P. A. Rochford, and H. E. Hurlburt, 2003: Mixed layer depth variability over the global ocean., J. Geophys. Res., 1083079, doi: 10.1029/2000C000736.10.1029/2000JC000736

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2000JC000736%2Ffull

http://onlinelibrary.wiley.com/doi/10.1029/2000JC000736/fullAbstract Top of page Abstract 1.Introduction 2.Data and Limitations 3.Mixed Layer Processes and MLD Criterion 4.Overview of Global MLD Variability 5.ILD and MLD Correspondence 6.Validation of ILD Versus MLD Correspondence 7.Conclusions Acknowledgments References Supporting Information [1] The spatial and monthly variability of the climatological mixed layer depth (MLD) for the global ocean is examined using the recently developed Naval Research Laboratory (NRL) Ocean Mixed Layer Depth (NMLD) climatologies. The MLD fields are constructed using the subsurface temperature and salinity data from the World Ocean Atlas 1994 [ Levitus et al. , 1994 ; Levitus and Boyer , 1994 ]. To minimize the limitations of these global data in the MLD determination, a simple mixing scheme is introduced to form a stable water column. Using these new data sets, global MLD characteristics are produced on the basis of an optimal definition that employs a density-based criterion having a fixed temperature difference of T = 0.8C and variable salinity. Strong seasonality of MLD is found in the subtropical Pacific Ocean and at high latitudes, as well as a very deep mixed layer in the North Atlantic Ocean in winter and a very shallow mixed layer in the Antarctic in all months. Using the climatological monthly MLD and isothermal layer depth (ILD) fields from the NMLD climatologies, an annual mean T field is presented, providing criteria for determining an ILD that is approximately equivalent to the optimal MLD. This enables MLD to be determined in cases where salinity data are not available. The validity of the correspondence between ILD and MLD is demonstrated using daily averaged subsurface temperature and salinity from two moorings: a Tropical Atmosphere Ocean array mooring in the western equatorial Pacific warm pool, where salinity stratification is important, and a Woods Hole Oceanographic Institute (WHOI) mooring in the Arabian Sea, where strongly reversing seasonal monsoon winds prevail. In the western equatorial Pacific warm pool the use of ILD criterion with an annual mean T value of 0.3C yields comparable results with the optimal MLD, while large T values yield an overestimated MLD. An analysis of ILD and MLD in the WHOI mooring show that use of an incorrect T criterion for the ILD may underestimate or overestimate the optimal MLD. Finally, use of the spatial annual mean T values constructed from the NMLD climatologies can be used to estimate the optimal MLD from only subsurface temperature data via an equivalent ILD for any location over the global ocean.

Kraus E. B., J. S. Turner, 1967: A one-dimensional model of the seasonal thermocline II. The general theory and its consequences. Tellus, 19( 1), 98- 106.10.1111/j.2153-3490.1967.tb01462.x

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1111%2Fj.2153-3490.1967.tb01462.x%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1111/j.2153-3490.1967.tb01462.x/citedbyA theory of the layer formation due to surface processes is presented, which is more general than that used in the preceding paper I. Convection due to heating at depth and cooling at the surface is included, as well as the mechanical stirring due to wind action. The theory is applicable to arbitrary forms of heating, including intermittent or continuous processes, and could be used to investigate diurnal as well as seasonal effects. A detailed application is made to the case treated approximately in I, for which a solution is now obtained in analytic form.The results obtained allow a quantitative, as well as qualitative, comparison with the ocean. It is found that reasonable layer depths are predicted using measured heating rates, and a value of the turbulent kinetic energy input to the water deduced from the mean surface stress. The effects of heating at depth can be comparable with wind stirring, even when the temperature of the upper layer is increasing. During the winter, convection due to surface cooling dominates the processes which deepen the layer.

Kraus E. B., J. A. Businger, 1995: Atmosphere-Ocean Interaction,2nd ed., Oxford University Press, 362 pp.10.1017/S002211207321162X

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http://ci.nii.ac.jp/ncid/BA23771309The representative of Department of investigation of flight accidents of the Ministry of transport of the great Britain has informed, that on the facts of the crash will be investigated. In sezone-2009 10 became the best assistant among the defenders in the Finnish

Long S.-M., S.-P. Xie, X.-T. Zheng, and Q. Y. Liu, 2014: Fast and slow responses to global warming: Sea surface temperature and precipitation patterns. J. Climate, 27( 1), 285- 299.10.1175/JCLI-D-13-00297.1

5aef149cc91f2d5d11bce02b01ae1617

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2014JCli...27..285L

http://adsabs.harvard.edu/abs/2014JCli...27..285LThe time-dependent response of sea surface temperature (SST) to global warming and the associated atmospheric changes are investigated based on a 1% yr 1 CO2 increase to the quadrupling experiment of the Geophysical Fluid Dynamics Laboratory Climate Model, version 2.1. The SST response consists of a fast component, for which the ocean mixed layer is in quasi equilibrium with the radiative forcing, and a slow component owing to the gradual warming of the deeper ocean in and beneath the thermocline. A diagnostic method is proposed to isolate spatial patterns of the fast and slow responses. The deep ocean warming retards the surface warming in the fast response but turns into a forcing for the slow response. As a result, the fast and slow responses are nearly opposite to each other in spatial pattern, especially over the subpolar North Atlantic/Southern Ocean regions of the deep-water/bottom-water formation, and in the interhemispheric SST gradient between the southern and northern subtropics. Wind-evaporation-SST feedback is an additional mechanism for the SST pattern formation in the tropics. Analyses of phase 5 of the Coupled Model Intercomparison Project (CMIP5) multimodel ensemble of global warming simulations confirm the validity of the diagnostic method that separates the fast and slow responses. Tropical annual rainfall change follows the SST warming pattern in both the fast and slow responses in CMIP5, increasing where the SST increase exceeds the tropical mean warming.

Luo Y. Y., Q. Y. Liu, and L. M. Rothstein, 2009: Simulated response of north Pacific mode waters to global warming. Geophys. Res. Lett., 36,L23609, doi: 10.1029/2009GL040906.10.1029/2009GL040906

263773f58656265a816fc286db80caa2

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2009GL040906%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1029/2009GL040906/abstract[1] This study investigates the response of the Mode Waters in the North Pacific to global warming based on a set of Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) models. Solutions between a present-day climate and a future, warmer climate are compared. Under the warmer climate scenario, the Mode Waters are produced on lighter isopycnal surfaces and are significantly weakened in terms of their formation and evolution. These changes are due to a more stratified upper ocean and thus a shoaling of the winter mixing depth resulting mainly from a reduction of the ocean-to-atmosphere heat loss over the subtropical region. The basin-wide wind stress may adjust the Mode Waters indirectly through its impact on the surface heat flux and subduction process.

Mann K., J. Lazier, 2005: Dynamics of Marine Ecosystems: Biological-Physical Interactions in the Oceans. Wiley-Blackwell,496 pp.10.1016/S0025-326X(97)00072-6

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1111%2Fj.1365-2419.1992.tb00029.x%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2419.1992.tb00029.x/abstractNo abstract is available for this article.

Murtugudde R., J. Beauchamp, C. R. McClain, M. Lewis, and A. J. Busalacchi, 2002: Effects of penetrative radiation on the upper tropical Ocean circulation. J. Climate, 15( 5), 470- 486.10.1175/1520-0442(2002)015<0470:EOPROT>2.0.CO;2

85d29fd84f8b723106ec13fdd16a27e7

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2002JCli...15..470M

http://adsabs.harvard.edu/abs/2002JCli...15..470MThe effects of penetrative radiation on the upper tropical ocean circulation have been investigated with an ocean general circulation model (OGCM) with attenuation depths derived from remotely sensed ocean color data. The OGCM is a reduced gravity, primitive equation, sigma coordinate model coupled to an advective atmospheric mixed layer model. These simulations use a single exponential profile for radiation attenuation in the water column, which is quite accurate for OGCMs with fairly coarse vertical resolution. The control runs use an attenuation depth of 17 m while the simulations use spatially variable attenuation depths. When a variable depth oceanic mixed layer is explicitly represented with interactive surface heat fluxes, the results can be counterintuitive. In the eastern equatorial Pacific, a tropical ocean region with one of the strongest biological activity, the realistic attenuation depths result in increased loss of radiation to the subsurface, but result in increased sea surface temperatures (SSTs) compared to the control run. Enhanced subsurface heating leads to weaker stratification, deeper mixed layers, reduced surface divergence, and hence less upwelling and entrainment. Thus, some of the systematic deficiencies in the present-day climate models, such as the colder than observed cold tongue in the equatorial Pacific may simply be related to inaccurate representation of the penetrative radiation and can be improved by the formulation presented here. The differences in ecosystems in each of the tropical oceans are clearly manifested in the manner in which biological heat trapping affects the upper ocean. While the tropical Atlantic has many similarities to the Pacific, the Amazon, Congo, and Niger Rivers' discharges dominate the attenuation of radiation. In the Indian Ocean, elevated biological activity and heat trapping are away from the equator in the Arabian Sea and the southern Tropics. For climate models, in view of their sensitivity to...

Nakamoto S., S. P. Kumar, J. M. Oberhuber, J. Ishizaka, K. Muneyama, and R. Frouin, 2001: Response of the equatorial Pacific to chlorophyll pigment in a mixed layer isopycnal ocean general circulation model. Geophys. Res. Lett., 28( 10), 2021- 2024.10.1029/2000GL012494

89ef5d21154a53bd9abb70e209efbe21

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2000GL012494%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1029/2000GL012494/abstractThe influence of phytoplankton on the upper ocean dynamics and thermodynamics in the equatorial Pacific is investigated using an isopycnal ocean general circulation model (OPYC) coupled with a mixed layer model and remotely sensed chlorophyll pigment concentration from the Coastal Zone Color Scanner (CZCS). In the equatorial Pacific heat accumulation due to a higher abundance of chlorophyll pigments in the equatorial Pacific leads to a decrease of the mixed layer thickness. This generates anomalous westward geostrophic currents north and south of the equator. In the western equatorial Pacific, these anomalous geostrophic currents merge into and strengthen the equatorial undercurrent (EUC), supplying water mass from the 200 m depth to the eastern equatorial Pacific. This chlorophyll-induced response of the undercurrent enhances upwelling around 110W, resulting in a lower sea surface temperature (SST) than without chlorophyll. Thus, thermal gradients due to absorption of solar radiation by phytoplankton may contribute remotely to equatorial upwelling in the eastern Pacific.

Qiu B., K. A. Kelly, 1993: Upper-ocean heat balance in the Kuroshio extension region. J. Phys. Oceanogr., 23( 9), 2027- 2041.10.1175/1520-0485(1993)023<2027:UOHBIT>2.0.CO;2

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1993JPO....23.2027Q

http://adsabs.harvard.edu/abs/1993JPO....23.2027QAbstract A horizontally two-dimensional mixed-layer model is used to study the upper-ocean heat balance in the Kuroshio Extension region (30°–40°N, 141°–175°E). Horizontal dependency is emphasized because, in addition to vertical entrainment and surface thermal forcing, horizontal advection and eddy diffusion make substantial contributions to changes in the upper-ocean thermal structure in this region. By forcing the model using the wind and heat flux data from ECMWF and the absolute sea surface height data deduced from the Geosat ERM, the mixed-layer depth ( h m ) and temperature ( T m ) changes in the Kuroshio Extension are hindcast for a 2.5-year period (November 1986–April 1989). Both phase and amplitude of the modeled T m and h m variations agreed well with the climatology. The horizontal thermal patterns also agreed favorably with the available in situ SST observations, but this agreement depended crucially on the inclusion of horizontal advections. Although the annually averaged net heat flux from the atmosphere to the ocean ( Q net ) is negative over the Kuroshio Extension region, the effect of the surface thermal forcing, when integrated annually, is to increase T m because the large, negative Q net in winter is redistributed in a much deeper mixed layer than it is in summer when Q net > 0. This warming effect is counterbalanced by the vertical turbulent entrainment through the base of the mixed layer (35% when annually integrated), the Ekman divergence (16%), the geostrophic divergence (12%), and the horizontal eddy diffusion (35%). Though small when averaged in space and time, the temperature advection by the surface flows makes a substantial contribution to the local heat balances. While it warms the upstream region of the Kuroshio Extension (west of 150°E), the current advection tends to cool the upper ocean over the vast downstream region due to the presence of the recirculation gyre.

Qiu B., N. Schneider, and S. M. Chen, 2007: Coupled decadal variability in the north pacific: An observationally constrained idealized model. J. Climate, 20( 14), 3602- 3620.a9fb9946-e5b6-47ad-a2cb-f71ea0884c93

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refpaperuri:(a2fa8f28e90550e6176a8f216a50822a)

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Sakamoto T. T., H. Hasumi, M. Ishii, S. Emori, T. Suzuki, T. Nishimura, and A. Sumi, 2005: Responses of the Kuroshio and the Kuroshio extension to global warming in a high-resolution climate model. Geophys. Res. Lett., 32,L14617, doi: 10.1029/2005GL023384.10.1029/2005GL023384

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2005GL023384%2Ffull

http://onlinelibrary.wiley.com/doi/10.1029/2005GL023384/fullABSTRACT Using a high-resolution atmosphere-ocean coupled climate model, responses of the Kuroshio and the Kuroshio Extension (KE) to global warming are investigated. In a climate change experiment with atmospheric CO2 concentration ideally increased by 1% year-1, the current velocity of the Kuroshio and KE increases, while the latitude of the Kuroshio separation to the east of Japan does not change significantly. The increase of the current velocity is up to 0.3 m s-1 at 150E. This acceleration of the Kuroshio and KE is due to changes in wind stress over the North Pacific and consequent spin-up of the Kuroshio recirculation gyre. The acceleration of the currents may affect sea level along the southern coast of Japan and northward heat transport under global warming.

Sato Y., S. Yukimoto, H. Tsujino, H. Ishizaki, and A. Noda, 2006: Response of North Pacific Ocean circulation in a Kuroshio-resolving ocean model to an Arctic Oscillation (AO)-like change in Northern Hemisphere atmospheric circulation due to greenhouse-gas forcing. J. Meteor. Soc.Japan, 84, 295- 309.10.2151/jmsj.84.295

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67128fb67d2857446cd3667232e169fa

http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F130004434931

refpaperuri:(a4e814ef6450a3b2d98e4644ee767897)

http://ci.nii.ac.jp/naid/130004434931Time-slice experiments are performed using a high-resolution North Pacific ocean general circulation model (NPOGCM) resolving the strong currents near Japan, such as the Kuroshio and the Oyashio, to investigate the effect of global warming on the North Pacific ocean circulation. The NPOGCM is forced by heat, momentum, and fresh-water fluxes obtained from a global warming projection using a global climate model (MRI-CGCM2.2). The annual mean sea-level pressure trend exhibits an annular pattern similar to the positive phase of the Arctic Oscillation in a global warming projection by MRI-CGCM2.2 based on the Intergovernmental Panel on Climate Change (IPCC) SRES A2 emission scenario. Associated with this trend, the anticyclonic atmospheric circulation is intensified over the mid-latitude North-Pacific, leading to a north-ward shift of the oceanic subtropical wind-driven gyre boundary, where extensions of the Kuroshio exist in MRI-CGCM2.2. Under these forcing changes, NPOGCM projects that in the future climate warm core eddies are more frequently pinched off from the Kuroshio off the eastern coast of Japan, leading to an annual mean SST rise over 5K at its maximum, compared with the present climate. The projected annual mean sea-level rise ranges from 12 to 18 cm along the coasts of Japan, and about 40 cm over the ocean east of Japan.

Sverdrup H. U., 1953: On conditions for the vernal blooming of phytoplankton. Journal du Conseil International Pour l'Exploration de la Mer, 18( 3), 287- 295.10.1093/icesjms/18.3.287

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http%3A%2F%2Ficesjms.oxfordjournals.org%2Fcontent%2F18%2F3%2F287.full.pdf

http://icesjms.oxfordjournals.org/content/18/3/287.full.pdfPublication » On conditions for the vernal blooming of phytoplankton.

Taguchi B., S.-P. Xie, N. Schneider, M. Nonaka, H. Sasaki, and Y. Sasai, 2007: Decadal variability of the Kuroshio extension: observations and an eddy-resolving model hindcast. J. Climate, 20( 11), 2357- 2377.10.1175/JCLI4142.1

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2007JCli...20.2357T

http://adsabs.harvard.edu/abs/2007JCli...20.2357TLow-frequency variability of the Kuroshio Extension (KE) is studied using observations and a multidecadal (195009-2003) hindcast by a high-resolution (0.100°), eddy-resolving, global ocean general circulation model for the Earth Simulator (OFES). In both the OFES hindcast and satellite altimeter observations, low-frequency sea surface height (SSH) variability in the North Pacific is high near the KE front. An empirical orthogonal function (EOF) analysis indicates that much of the SSH variability in the western North Pacific east of Japan is explained by two modes with meridional structures tightly trapped along the KE front. The first mode represents a southward shift and to a lesser degree, an acceleration of the KE jet associated with the 1976/77 shift in basin-scale winds. The second mode reflects quasi-decadal variations in the intensity of the KE jet. Both the spatial structure and time series of these modes derived from the hindcast are in close agreement with observations. A linear Rossby wave model forced by observed wind successfully reproduces the time series of the leading OFES modes but fails to explain why their meridional structure is concentrated on the KE front and inconsistent with the broadscale wind forcing. Further analysis suggests that KE variability may be decomposed into broad- and frontal-scale components in the meridional direction09恪眛he former following the linear Rossby wave solution and the latter closely resembling ocean intrinsic modes derived from an OFES run forced by climatological winds. The following scenario is suggested for low-frequency KE variability: basin-scale wind variability excites broadscale Rossby waves, which propagate westward, triggering intrinsic modes of the KE jet and reorganizing SSH variability in space.

Taylor J. R., R. Ferrari, 2011: Shutdown of turbulent convection as a new criterion for the onset of spring phytoplankton blooms. Limnology and Oceanography, 56( 6), 2293- 2307.10.4319/lo.2011.56.6.2293

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http://onlinelibrary.wiley.com/doi/10.4319/lo.2011.56.6.2293/citedbyThe onset of phytoplankton blooms in late winter, early spring has been traditionally associated with the shoaling of the mixed layer above a critical depth. Here we show that the onset of a bloom can also be triggered by a reduction in air–sea fluxes at the end of winter. When net cooling subsides at the end of winter, turbulent mixing becomes weak, thereby increasing the residence time of phytoplankton cells in the euphotic layer and allowing a bloom to develop. The necessary change in the air–sea flux generally precedes mixed-layer shoaling, and may provide a better indicator for the onset of the spring bloom than the mixed-layer depth alone. Our hypothesis is supported by numerical simulations and remote sensing data.

Taylor K. E., R. J. Stouffer, and G. A. Meehl, 2012: An overview of CMIP5 and the experiment design. Bull. Amer. Meteor. Soc., 93( 4), 485- 498.10.1175/BAMS-D-11-00094.1

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2012BAMS...93..485T

refpaperuri:(102c64f576f0dc49ca552e6df691421b)

http://adsabs.harvard.edu/abs/2012BAMS...93..485TThe fifth phase of the Coupled Model Intercomparison Project (CMIP5) will produce a state-of-the- art multimodel dataset designed to advance our knowledge of climate variability and climate change. Researchers worldwide are analyzing the model output and will produce results likely to underlie the forthcoming Fifth Assessment Report by the Intergovernmental Panel on Climate Change. Unprecedented in scale and attracting interest from all major climate modeling groups, CMIP5 includes “long term” simulations of twentieth-century climate and projections for the twenty-first century and beyond. Conventional atmosphere–ocean global climate models and Earth system models of intermediate complexity are for the first time being joined by more recently developed Earth system models under an experiment design that allows both types of models to be compared to observations on an equal footing. Besides the longterm experiments, CMIP5 calls for an entirely new suite of “near term” simulations focusing on recent decades and the future to year 2035. These “decadal predictions” are initialized based on observations and will be used to explore the predictability of climate and to assess the forecast system's predictive skill. The CMIP5 experiment design also allows for participation of stand-alone atmospheric models and includes a variety of idealized experiments that will improve understanding of the range of model responses found in the more complex and realistic simulations. An exceptionally comprehensive set of model output is being collected and made freely available to researchers through an integrated but distributed data archive. For researchers unfamiliar with climate models, the limitations of the models and experiment design are described.

Vecchi G. A., B. J. Soden, 2007: Global warming and the weakening of the tropical circulation. J. Climate, 20( 17), 4316- 4340.10.1175/JCLI4258.1

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2006AGUFMOS11A1467W

refpaperuri:(b30ccd0a9e8c71855c1ae5c8c7674dc2)

http://adsabs.harvard.edu/abs/2006AGUFMOS11A1467WAbstract This study examines the response of the tropical atmospheric and oceanic circulation to increasing greenhouse gases using a coordinated set of twenty-first-century climate model experiments performed for the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). The strength of the atmospheric overturning circulation decreases as the climate warms in all IPCC AR4 models, in a manner consistent with the thermodynamic scaling arguments of Held and Soden. The weakening occurs preferentially in the zonally asymmetric (i.e., Walker) rather than zonal-mean (i.e., Hadley) component of the tropical circulation and is shown to induce substantial changes to the thermal structure and circulation of the tropical oceans. Evidence suggests that the overall circulation weakens by decreasing the frequency of strong updrafts and increasing the frequency of weak updrafts, although the robustness of this behavior across all models cannot be confirmed because of the lack of data. As the climate warms, changes in both the atmospheric and ocean circulation over the tropical Pacific Ocean resemble “El Ni09o–like” conditions; however, the mechanisms are shown to be distinct from those of El Ni09o and are reproduced in both mixed layer and full ocean dynamics coupled climate models. The character of the Indian Ocean response to global warming resembles that of Indian Ocean dipole mode events. The consensus of model results presented here is also consistent with recently detected changes in sea level pressure since the mid–nineteenth century.

Wu L., Z. Liu, R. Gallimore, R. Jacob, D. Lee, and Y. Zhong, 2003: Pacific decadal variability: The tropical Pacific mode and the north Pacific mode. J. Climate, 16( 8), 1101- 1120.21717738-dafd-4061-ad47-3c28e28c76d1

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refpaperuri:(983b2f921f0aca1092e170b0258c11c9)

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Wu, L. X., Coauthors , 2012: Enhanced warming over the global subtropical western boundary currents. Nature Climate Change, 2( 3), 161- 166.10.1038/nclimate1353

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http://www.nature.com/nclimate/journal/v2/n3/nclimate1353/metricsSubtropical western boundary currents are warm, fast-flowing currents that form on the western side of ocean basins. They carry warm tropical water to the mid-latitudes and vent large amounts of heat and moisture to the atmosphere along their paths, affecting atmospheric jet streams and mid-latitude storms, as well as ocean carbon uptake. The possibility that these highly energetic currents might change under greenhouse-gas forcing has raised significant concerns, but detecting such changes is challenging owing to limited observations. Here, using reconstructed sea surface temperature datasets and century-long ocean and atmosphere reanalysis products, we find that the post-1900 surface ocean warming rate over the path of these currents is two to three times faster than the global mean surface ocean warming rate. The accelerated warming is associated with a synchronous poleward shift and/or intensification of global subtropical western boundary currents in conjunction with a systematic change in winds over both hemispheres. This enhanced warming may reduce the ability of the oceans to absorb anthropogenic carbon dioxide over these regions. However, uncertainties in detection and attribution of these warming trends remain, pointing to a need for a long-term monitoring network of the global western boundary currents and their extensions.

Xie S.-P., C. Deser, G. A. Vecchi, J. Ma, H. Y. Teng, and A. T. Wittenberg, 2010: Global warming pattern formation: Sea surface temperature and rainfall. J. Climate, 23( 4), 966- 986.10.1175/2009JCLI3329.1

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http%3A%2F%2Fwww.cabdirect.org%2Fabstracts%2F20103118162.html

refpaperuri:(b0ebeb07b4f54809d624dfe9936fb36c)

http://www.cabdirect.org/abstracts/20103118162.htmlAbstract Spatial variations in sea surface temperature (SST) and rainfall changes over the tropics are investigated based on ensemble simulations for the first half of the twenty-first century under the greenhouse gas (GHG) emission scenario A1B with coupled ocean tmosphere general circulation models of the Geophysical Fluid Dynamics Laboratory (GFDL) and National Center for Atmospheric Research (NCAR). Despite a GHG increase that is nearly uniform in space, pronounced patterns emerge in both SST and precipitation. Regional differences in SST warming can be as large as the tropical-mean warming. Specifically, the tropical Pacific warming features a conspicuous maximum along the equator and a minimum in the southeast subtropics. The former is associated with westerly wind anomalies whereas the latter is linked to intensified southeast trade winds, suggestive of wind vaporation ST feedback. There is a tendency for a greater warming in the northern subtropics than in the southern subtropics in accordance with asymmetries in trade wind changes. Over the equatorial Indian Ocean, surface wind anomalies are easterly, the thermocline shoals, and the warming is reduced in the east, indicative of Bjerknes feedback. In the midlatitudes, ocean circulation changes generate narrow banded structures in SST warming. The warming is negatively correlated with wind speed change over the tropics and positively correlated with ocean heat transport change in the northern extratropics. A diagnostic method based on the ocean mixed layer heat budget is developed to investigate mechanisms for SST pattern formation. Tropical precipitation changes are positively correlated with spatial deviations of SST warming from the tropical mean. In particular, the equatorial maximum in SST warming over the Pacific anchors a band of pronounced rainfall increase. The gross moist instability follows closely relative SST change as equatorial wave adjustments flatten upper-tropospheric warming. The comparison with atmospheric simulations in response to a spatially uniform SST warming illustrates the importance of SST patterns for rainfall change, an effect overlooked in current discussion of precipitation response to global warming. Implications for the global and regional response of tropical cyclones are discussed.

Xu L. X., S.-P. Xie, and Q. Y. Liu, 2012: Mode water ventilation and subtropical countercurrent over the north Pacific in CMIP5 simulations and future projections. J. Geophys. Res.-Oceans, 117,C12009, doi: 10.1029/2012JC008377.10.1029/2012JC008377

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refpaperuri:(a457eb87eca80cea5de2eddefbe2c0d4)

http://onlinelibrary.wiley.com/doi/10.1029/2012JC008377/citedby[1] Seventeen coupled general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are analyzed to assess the dynamics and variability of the North Pacific Subtropical Countercurrent (STCC). Consistent with observations, the STCC is anchored by mode water to the north. For the present climate, the STCC tends to be stronger in models than in observations because of too strong a low potential vorticity signature of mode water. There are significant variations in mode water simulation among models, i.e., in volume and core layer density. The northeast slanted bands of sea surface height (SSH) anomalies associated with the STCC variability are caused by variability in mode water among models and the Hawaii islands are represented in some models, where the island-induced wind curls drive the Hawaiian Lee Countercurrent (HLCC) located to the south of STCC. Projected future changes in STCC and mode water under the Representative Concentration Pathways (RCP) 4.5 scenario are also investigated. By combining the historical and RCP 4.5 runs, an empirical orthogonal function analysis for SSH over the central subtropical gyre (160 E–140W, 15 –30N) is performed. The dominant mode of SSH change in 17 CMIP5 models is characterized by the weakening of the STCC because of the reduced formation of mode water. The weakened mode water is closely related to the increased stratification of the upper ocean, the latter being one of the most robust changes as climate warms. Thus the weakened STCC and mode water are common to CMIP5 future climate projections.

Xu L. X., S.-P. Xie, and Q. Y. Liu, 2013: Fast and slow responses of the north Pacific mode water and subtropical countercurrent to global warming. Journal of Ocean University of China, 12( 2), 216- 221.10.1007/s11802-013-2189-6

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Six coupled general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are employed for examining the full evolution of the North Pacific mode water and Subtropical Countercurrent (STCC) under global warming over 400 years following the Representative Concentration Pathways (RCP) 4.5. The mode water and STCC first show a sharp weakening trend when the radiative forcing increases, but then reverse to a slow strengthening trend of smaller magnitude after the radiative forcing is stablized. As the radiative forcing increases during the 21st century, the ocean warming is surface-intensified and decreases with depth, strengthening the upper ocean's stratification and becoming unfavorable for the mode water formation. Moving southward in the subtropical gyre, the shrinking mode water decelerates the STCC to the south. After the radiative forcing is stabilized in the 2070s, the subsequent warming is greater at the subsurface than at the sea surface, destabilizing the upper ocean and becoming favorable for the mode water formation. As a result, the mode water and STCC recover gradually after the radiative forcing is stabilized.

Xu L. X., S.-P. Xie, J. L. McClean, Q. Y. Liu, and H. Sasaki, 2014: Mesoscale eddy effects on the subduction of north Pacific mode waters. J. Geophys. Res.,119, 4867-4886, doi: 10.1002/2014JC009861.10.1002/2014JC009861

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2F2014JC009861%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1002/2014JC009861/abstractAbstract Mesoscale eddy effects on the subduction of North Pacific mode waters are investigated by comparing observations and ocean general circulation models where eddies are either parameterized or resolved. The eddy-resolving models produce results closer to observations than the noneddy-resolving model. There are large discrepancies in subduction patterns between eddy-resolving and noneddy-resolving models. In the noneddy-resolving model, subduction on a given isopycnal is limited to the cross point between the mixed layer depth (MLD) front and the outcrop line whereas in eddy-resolving models and observations, subduction takes place in a broader, zonally elongated band within the deep mixed layer region. Mesoscale eddies significantly enhance the total subduction rate, helping create remarkable peaks in the volume histogram that correspond to North Pacific subtropical mode water (STMW) and central mode water (CMW). Eddy-enhanced subduction preferentially occurs south of the winter mean outcrop. With an anticyclonic eddy to the west and a cyclonic eddy to the east, the outcrop line meanders south, and the thermocline/MLD shoals eastward. As eddies propagate westward, the MLD shoals, shielding the water of low potential vorticity from the atmosphere. The southward eddy flow then carries the subducted water mass into the thermocline. The eddy subduction processes revealed here have important implications for designing field observations and improving models.

Yentsch C. S., 1990: Estimates of `new production' in the Mid-North Atlantic. Journal of Plankton Research, 12, 717- 734.10.1093/plankt/12.4.717

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http%3A%2F%2Fplankt.oxfordjournals.org%2Fcontent%2F12%2F4%2F717.short

refpaperuri:(ae2af3ec447c817bbac8afc2a792751c)

http://plankt.oxfordjournals.org/content/12/4/717.shortAbstract The principal aim of this paper is to demonstrate how the major features of primary production are influenced by climatological change. The roles played by seasonal change in mixed layer depth and the vertical distribution of a key limiting nutrient are emphasized. The model traces the sequences of primary production as the sun moves from the winter to summer solstice. Seasonal change in primary production is regulated by light at high latitudes during winter months and nutrients during summer months, where at mid and low latitudes nutrients limit production. The annual pattern of production down the central meridian reflects the vertical distribution of nitrate-nitrogen in cross-sections of the mid-ocean. In turn, this pattern of nutrient distribution reflects the density structure due to the currents and gyres of the North Atlantic. The model produces estimates of ‘new primary production’ which are consistent when compared with measured values. It should be useful for global estimates of primary production.

Yim B. Y., Y. Noh, S. W. Yeh, J. S. Kug, H. S. Min, and B. Qiu, 2013: Ocean mixed layer processes in the Pacific decadal oscillation in coupled general circulation models. Climate Dyn., 41( 5-6), 1407- 1417.10.1007/s00382-012-1630-7

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http%3A%2F%2Flink.springer.com%2F10.1007%2Fs00382-012-1630-7

http://link.springer.com/10.1007/s00382-012-1630-7It is investigated how the Pacific Decadal Oscillation (PDO) is simulated differently among various coupled general circulation models (CGCMs), and how it is related to the heat budget of the simulated ocean mixed layer, which includes the surface heat flux and ocean heat transport. For this purpose the dataset of the climate of the 20th Century experiment (20C3M) from nine CGCMs reported to IPCC AR4 are used, while the MRI and MIROC models are examined in detail. Detailed analyses of these two CGCMs reveal that the PDO is mainly affected by ocean heat transport rather than surface heat flux, in particular in the MRI model which has a larger contribution of ocean heat transport to the heat budget. It is found that the ocean heat transport due to Ekman advection versus geostrophic advection contributes differently to the PDO in the western and central North Pacific. Specifically, the strength of PDO tends to be larger for CGCMs with a larger ocean heat transport in the region.

Yu L., X. Jin, and R. A. Weller, 2006: Role of net surface heat flux in seasonal variations of sea surface temperature in the tropical Atlantic Ocean. J. Climate, 19( 23), 6153- 6169.10.1175/JCLI3970.1

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2006JCli...19.6153Y

http://adsabs.harvard.edu/abs/2006JCli...19.6153YThe present study used a new net surface heat flux (Qnet) product obtained from the Objective Analyzed Air09 ea Fluxes (OAFlux) project and the International Satellite Cloud Climatology Project (ISCCP) to examine two specific issues09ne is to which degree Qnet controls seasonal variations of sea surface temperature (SST) in the tropical Atlantic Ocean (2000°S09 2000°N, east of 6000°W), and the other is whether the physical relation can serve as a measure to evaluate the physical representation of a heat flux product. To better address the two issues, the study included the analysis of three additional heat flux products: the Southampton Oceanographic Centre (SOC) heat flux analysis based on ship reports, and the model fluxes from the National Centers for Environmental Prediction09 ational Center for Atmospheric Research (NCEP09 CAR) reanalysis and the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40). The study also uses the monthly subsurface temperature fields from the World Ocean Atlas to help analyze the seasonal changes of the mixed layer depth (hMLD). The study showed that the tropical Atlantic sector could be divided into two regimes based on the influence level of Qnet. SST variability poleward of 500°S and 1000°N is dominated by the annual cycle of Qnet. In these regions the warming (cooling) of the sea surface is highly correlated with the increased (decreased) Qnet confined in a relatively shallow (deep) hMLD. The seasonal evolution of SST variability is well predicted by simply relating the local Qnet with a variable hMLD. On the other hand, the influence of Qnet diminishes in the deep Tropics within 500°S and 1000°N and ocean dynamic processes play a dominant role. The dynamics-induced changes in SST are most evident along the two belts, one of which is located on the equator and the other off the equator at about 300°N in the west, which tilts to about 1000°N near the northwestern African coast. The study also showed that if the degree of consistency between the correlation relationships of Qnet, hMLD, and SST variability serves as a measure of the quality of the Qnet product, then the Qnet from OAFlux + ISCCP and ERA-40 are most physically representative, followed by SOC. The NCEP09 CAR Qnet is least representative. It should be noted that the Qnet from OAFlux + ISCCP and ERA-40 have a quite different annual mean pattern. OAFlux + ISCCP agrees with SOC in that the tropical Atlantic sector gains heat from the atmosphere on the annual mean basis, where the ERA-40 and the NCEP09 CAR model reanalyses indicate that positive Qnet occurs only in the narrow equatorial band and in the eastern portion of the tropical basin. Nevertheless, seasonal variances of the Qnet from OAFlux + ISCCP and ERA-40 are very similar once the respective mean is removed, which explains why the two agree with each other in accounting for the seasonal variability of SST. In summary, the study suggests that an accurate estimation of surface heat flux is crucially important for understanding and predicting SST fluctuations in the tropical Atlantic Ocean. It also suggests that future emphasis on improving the surface heat flux estimation should be placed more on reducing the mean bias.