Oceanic Rossby waves can propagate climate signals over considerable distances over long timescales. Using a long simulation from a coupled climate model, we examine oceanic and mixed atmosphere‐ocean teleconnections to the south‐western Indian Ocean (SWIO) associated with Rossby waves excited by the El Niño‐Southern Oscillation (ENSO). Reconstruction of propagating ENSO‐induced sea‐level anomalies from the simulation using an optimized linear wave model with dissipation highlights the prominent role of baroclinic, rather than barotropic, Rossby waves in modulating sea‐surface heights. Between 9.5° and 18.5°S, El Niño‐associated anomalous anticyclonic wind‐stress fields initiate downwelling Rossby waves, potentially influencing SWIO regional climate around 1–4 seasons after El Niño peak, while also destructively interfering with upwelling waves triggered on the eastern boundary by oceanic teleconnections. Further south, weaker ENSO winds, dissipation, non‐linear processes, and interference from higher‐mode Rossby waves limit ENSO influences in the SWIO. In the model, ENSO‐associated predictability is therefore constrained by the “atmospheric” rather than “oceanic” bridge.
The behaviour of steady jet-like flows is examined in a low-Rossby-number rotating fluid. Unlike the corresponding non-rotating flow, the momentum flux of a jet in a rotating fluid is not conserved with distance downstream and, as a consequence, the jet loses all of its momentum at a finite distance from the source, apparently developing a singularity as this occurs. The asymptotic properties of the flow leading up to this singular point are calculated for jets of various inflow widths and a structure which resolves the singularity that occurs in each of these cases is described. The properties on the approach to the singularity are shown to be similar to those of the exact solution described by Gadgil [12]. Both the asymptotic structure and the resolution of the singularity are, however, applicable to the expected breakdown of any form of jet in rotating fluid under similar conditions. The consequences of this are discussed, particularly in relation to the separated-flow structure proposed for motion past a cylindrical obstacle in Page [3].
The Indonesian Throughflow (ITF) is the tropical pathway connecting the Pacific Ocean (PO) and the Indian Ocean (IO) via a complex series of topographical barriers, with deep basins connected by shallow sills, linking the passages through the Indonesian archipelago (Gordon et al., 2003;Sprintall et al., 2009). The ITF plays a key role in the global overturning circulation. Gordon (1986) noted the importance of the Indonesian Throughflow (ITF) in the "warm-water route" of the upper overturning cell that ultimately feeds North Atlantic Deep Water production. ITF transport is a key component in the PO heat budget, linked to large-scale upwelling in the eastern PO (Toggweiler et al., 2019a;, and is important in influencing IO watermass characteristics and circulation (e.g.,
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.