Barry A. Klinger

Bio: Barry A. Klinger is an academic researcher from George Mason University. The author has contributed to research in topics: Wind stress & Thermocline. The author has an hindex of 19, co-authored 30 publications receiving 1371 citations. Previous affiliations of Barry A. Klinger include Massachusetts Institute of Technology & Nova Southeastern University.

A mechanism for generating ENSO decadal variability

Abstract: A coupled ocean-atmosphere model of the Pacific basin is used to illustrate a mechanism by which El Nino and the Southern Oscillation (ENSO) may be modulated on decadal time scales. For reasonable choices of model parameters, solutions exhibit two types of oscillation, an ENSO-like interannual mode and a decadal one. The decadal mode affects the equatorial zone by means of an oceanic teleconnection that involves transport variations of the North Pacific Subtropical Cell. Since almost half of the cool, thermocline water that upwells in the eastern equatorial Pacific participates in this cell, these variations significantly alter the extent of the cold tongue, and hence provide an efficient mechanism for modulating ENSO.

Meridional Circulation Cells and the Source Waters of the Pacific Equatorial Undercurrent

Abstract: A 3½-layer model is used to study the meridional circulation cells that provide the source waters of the Pacific Equatorial Undercurrent (EUC). Its three active layers represent tropical, thermocline, and upper-intermediate waters, respectively, and across-interface flow between the layers parameterizes the processes of upwelling, subduction, and diapycnal mixing. Solutions are driven by climatological winds in a domain resembling the Pacific basin from 35°S to 55°N. An additional forcing mechanism is a specified inflow into layer 3 across the open southern boundary and a compensating outflow from layers 1 and 2 along the western boundary just north of the equator; the resulting circulation simulates the Pacific interocean circulation (IOC), in which intermediate water enters the South Pacific and the same amount of thermocline and tropical waters exit via the Indonesian Throughflow. Five meridional cells contribute to the EUC in the main-run solution: north and south Subtropical Cells (STCs), no...

Experimental observations of baroclinic eddies on a sloping bottom

Abstract: Baroclinic eddies in a rotating box with a sloping bottom were produced by squirting dense salt water up the sloping bottom and along the “eastern” wall. The jet stagnated in shallow water and was ejected normal to the wall. For certain parameters (volume flux of jet, etc.), a coherent lens of dense bottom water formed and propagated west with an overlying cyclonic vortex. The circulation in the bottom lens, on the other hand, was relatively weak. No such eddy forms when the depth of fresh water is relatively deep, and a regime diagram is given for the formation of the coherent eddies. Thus a relatively simple structure emerges despite the complexity of the generating process. The pressure field determined from density measurements is discussed in terms of an integral theorem for coherent eddies, and the westward propagation is also related to previous theories. Several other techniques for generating such eddies are discussed.

Representation of convective plumes by vertical adjustment

Abstract: Open-ocean deep-water formation involves the interplay of two dynamical processes; plumes (≤1 km wide), driven by “upright” convection, and geostrophic eddies (≥5 km wide), driven by baroclinic instability. Numerical “twin” experiments are used to address two questions about the plumes: Can they be represented by a simple mixing process in large-scale models? If so, is it important that the mixing occurs over a finite time tmix, or would instantaneous mixing produce the same effect on large-scale properties? In numerical simulations which resolve the geostrophic eddies, we represent the plumes with a “slow” convective adjustment algorithm which is broadly equivalent to an enhanced vertical diffusivity of density in statically unstable regions. The diffusivity κ depends on tmix, the mixing timescale. The fidelity of the plume parameterization is then evaluated by comparison with plume-resolving simulations of open-ocean deep convection. Integral properties of the plumes, such as the temperature census of the convected water and the strength of the rim current that encircles the convecting region, are all accurately reproduced by the slow adjustment scheme. The importance of choosing an appropriate finite value for tmix is explored by setting tmix = 12 hours in some experiments, in accordance with scaling considerations, and tmix = 0 in others, corresponding to instantaneous adjustment, the conventional assumption. In the case of convection into a moderately or strongly stratified ocean the behavior does not significantly depend on tmix. However, in neutral conditions the slow adjustment does improve the parametric representation. Our experiments confirm the picture of plumes homogenizing the water column over a time tmix.

Meridional Heat Transport by the Subtropical Cell

Abstract: The wind-driven circulation adds a significant contribution to poleward meridional heat transport. Numerical models indicate that equatorward of ϕ0, the zero wind stress latitude (30° lat), most of the wind-induced heat transport is due to the meridional overturning circulation known as the subtropical cell. The volume transport of this overturning is approximately given by the surface Ekman transport. By combining this fact with the assumption that Ekman-downwelled water approximately follows isotherms except near the equator, the authors derive an expression for the meridional heat transport that depends only on wind stress and surface temperature. The expression is confirmed in numerical models with simplified geometry and forcing. Numerical results indicate that peak heat transport due to the subtropical cell is about 0.1 × 1015 W for the North Atlantic and 0.3 × 1015 W for the North Pacific.

Ensemble empirical mode decomposition: a noise-assisted data analysis method

Abstract: A new Ensemble Empirical Mode Decomposition (EEMD) is presented. This new approach consists of sifting an ensemble of white noise-added signal (data) and treats the mean as the final true result. Finite, not infinitesimal, amplitude white noise is necessary to force the ensemble to exhaust all possible solutions in the sifting process, thus making the different scale signals to collate in the proper intrinsic mode functions (IMF) dictated by the dyadic filter banks. As EEMD is a time–space analysis method, the added white noise is averaged out with sufficient number of trials; the only persistent part that survives the averaging process is the component of the signal (original data), which is then treated as the true and more physical meaningful answer. The effect of the added white noise is to provide a uniform reference frame in the time–frequency space; therefore, the added noise collates the portion of the signal of comparable scale in one IMF. With this ensemble mean, one can separate scales naturall...

Thinking fast and slow.

Abstract: In 1974 an article appeared in Science magazine with the dry-sounding title “Judgment Under Uncertainty: Heuristics and Biases” by a pair of psychologists who were not well known outside their discipline of decision theory. In it Amos Tversky and Daniel Kahneman introduced the world to Prospect Theory, which mapped out how humans actually behave when faced with decisions about gains and losses, in contrast to how economists assumed that people behave. Prospect Theory turned Economics on its head by demonstrating through a series of ingenious experiments that people are much more concerned with losses than they are with gains, and that framing a choice from one perspective or the other will result in decisions that are exactly the opposite of each other, even if the outcomes are monetarily the same. Prospect Theory led cognitive psychology in a new direction that began to uncover other human biases in thinking that are probably not learned but are part of our brain’s wiring.

From anchovies to sardines and back: multidecadal change in the Pacific Ocean.

Abstract: In the Pacific Ocean, air and ocean temperatures, atmospheric carbon dioxide, landings of anchovies and sardines, and the productivity of coastal and open ocean ecosystems have varied over periods of about 50 years. In the mid-1970s, the Pacific changed from a cool “anchovy regime” to a warm “sardine regime.” A shift back to an anchovy regime occurred in the middle to late 1990s. These large-scale, naturally occurring variations must be taken into account when considering human-induced climate change and the management of ocean living resources.

Heat transfer and large scale dynamics in turbulent Rayleigh-Bénard convection

Abstract: The progress in our understanding of several aspects of turbulent Rayleigh-Benard convection is reviewed. The focus is on the question of how the Nusselt number and the Reynolds number depend on the Rayleigh number Ra and the Prandtl number Pr, and on how the thicknesses of the thermal and the kinetic boundary layers scale with Ra and Pr. Non-Oberbeck-Boussinesq effects and the dynamics of the large scale convection roll are addressed as well. The review ends with a list of challenges for future research on the turbulent Rayleigh-Benard system.