The ventilated thermocline in quasigeostrophic approximation

The ventilated thermocline model of Luyten et al. (hereafter LPS), (1983) is reformulated in the quasigeostrophic approximation. The quasigeostrophic solutions with zonal outcrop lines capture the salient features of the solutions of LPS. When the outcrop lines are sufficiently nonzonal, the quasigeostrophic solutions resemble those of Parsons (1969), Veronis (1973), and Huang (1984), resolving an inconsistency in Parsons\u27 solution. But an attempt to close the quasigeostrophic solution having two moving layers with a western boundary current in which friction is parameterized as a linear drag coefficient results in an ill posed problem. The paper concludes with a comparison of cross-gyre ventilation in the quasigeostrophic and LPS formulations

2004 program of study : tides

The summer of 2004 saw the GFD program tackle “Tides”. Myrl Hendershott (Scripps Institution of Oceanography) gave a fabulous introduction to the subject in the first week of the course, laying the foundations from astronomy and classical geophysical fluid dynamics. In the second week, Chris Garrett (University of Victoria) admirably followed up with recent developments on the subject, including the recent observations from satellite altimetry, their implications to mixing and circulation, and even a memorable lecture on the noble theme of how we might solve the world's energy crisis. The principal lectures proved unusually popular this summer, and the seminar room at Walsh often overflowed in the first two weeks. Following on from the lectures, the seminar schedule of the summer covered in greater detail the oceanographic issues with which researchers are actively grappling. We also heard about related problems regarding atmospheric, planetary and stellar tides, together with the usual mix of topics on GFD in general. The summer once again featured a lecture for the general public in the Woods Hole area. Carl Wunsch delivered a very well received lecture entitled “Climate Change Stories”, in which he gave an impression of how scientists generally believe our climate is currently changing, whilst simultaneously urging caution against some of the more outrageous and exaggerated claims. The lecture was held at Lilly Auditorium, thanks to the hospitality of the Marine Biology Laboratory. The reception following the lecture was enjoyed by all. Neil Balmforth and Stefan Llewellyn Smith acted as Co-Directors for the summer. Janet Fields, Jeanne Fleming and Penny Foster provided the administrative backbone to the Program, both during the summer and throughout the year beforehand. As always, we were grateful to the Woods Hole Oceanographic Institution for the use of Walsh Cottage, and Keith Bradley's solid service could not be overlooked. Shilpa Ghadge and Shreyas Mandre are to be thanked for their part in comforting the fellows, developing the summer's proceedings volume (available on the GFD web site) and for running the computer network.Funding was provided by the Office of Naval Research under Contract No. N00014-04-1-0157 and the National Science Foundation under Grant No. OCE-0325296

Towards an end-to-end analysis and prediction system for weather, climate, and marine applications in the Red Sea

Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 102(1), (2021): E99-E122, https://doi.org/10.1175/BAMS-D-19-0005.1.The Red Sea, home to the second-longest coral reef system in the world, is a vital resource for the Kingdom of Saudi Arabia. The Red Sea provides 90% of the Kingdom’s potable water by desalinization, supporting tourism, shipping, aquaculture, and fishing industries, which together contribute about 10%–20% of the country’s GDP. All these activities, and those elsewhere in the Red Sea region, critically depend on oceanic and atmospheric conditions. At a time of mega-development projects along the Red Sea coast, and global warming, authorities are working on optimizing the harnessing of environmental resources, including renewable energy and rainwater harvesting. All these require high-resolution weather and climate information. Toward this end, we have undertaken a multipronged research and development activity in which we are developing an integrated data-driven regional coupled modeling system. The telescopically nested components include 5-km- to 600-m-resolution atmospheric models to address weather and climate challenges, 4-km- to 50-m-resolution ocean models with regional and coastal configurations to simulate and predict the general and mesoscale circulation, 4-km- to 100-m-resolution ecosystem models to simulate the biogeochemistry, and 1-km- to 50-m-resolution wave models. In addition, a complementary probabilistic transport modeling system predicts dispersion of contaminant plumes, oil spill, and marine ecosystem connectivity. Advanced ensemble data assimilation capabilities have also been implemented for accurate forecasting. Resulting achievements include significant advancement in our understanding of the regional circulation and its connection to the global climate, development, and validation of long-term Red Sea regional atmospheric–oceanic–wave reanalyses and forecasting capacities. These products are being extensively used by academia, government, and industry in various weather and marine studies and operations, environmental policies, renewable energy applications, impact assessment, flood forecasting, and more.The development of the Red Sea modeling system is being supported by the Virtual Red Sea Initiative and the Competitive Research Grants (CRG) program from the Office of Sponsored Research at KAUST, Saudi Aramco Company through the Saudi ARAMCO Marine Environmental Center at KAUST, and by funds from KAEC, NEOM, and RSP through Beacon Development Company at KAUST

SPECTRAL CHARACTERISTICS OF THE 1960 TSUNAMI AT CRESCENT CITY, CA

Spectral characteristics of sea level fluctuations during the May 1960 Chilean Earthquake tsunami are investigated using digitized strip chart recordings from two docks within Crescent City Harbor. Peaks in sea level spectra at the two docks near 10-3 Hz and near 2.1 x10-3 Hz correspond to the two lowest frequency harbor modes, occurring above the frequency band most strongly excited by the tsunami. Tidal modulation of harbor spectral structure at very short periods is observed. Theoretical estimates of shelf edge wave resonant modes fall within the frequency band strongly excited by the tsunami, in contrast to modeled edge waves from a seismic event near Cape Mendocino that show no evidence of the reflection necessary for a strong shelf resonance. This suggests that heightened susceptibility of sea level (but not necessarily currents) at Crescent City to tsunami is not due primarily to either harbor or shelf resonances

Final Report: The Santa Barbara Channel - Santa Maria Basin Circulation Study

In 1989, the National Research Council (NRC) was requested by President Bush, and by the Minerals Management Service (MMS), to review the adequacy of information available to assess the impact of oil and gas development on the Outer Continental Shelf. The MMS developed a Cooperative Agreement (CA) with the Scripps Institution of Oceanography (SIO) at the University of California, San Diego (UCSD). The study, named The Santa Barbara Channel - Santa Maria Basin Circulation study, was originally funded in 1989 and extended until 2005. It principally consisted of two components, one observational and the other a numerical modeling study that are described in the following. This report presents all of the scientific papers published to date in the peer reviewed scientific literature, that comprehensively describe the work performed by SIO UCSD and its partners at Princeton University, SUNY-Stony Brook and the Desert Research Institute as part of the CA

Upwelling” and cyclonic regimes of the near-surface circulation in the Santa Barbara Channel

Abstract. The observed near-surface circulation in the Santa Barbara Channel indicates in particular two patterns: a dominant cyclonic circulation mode and a less frequent upwelling flow mode. To explain the dynamics that may govern these two flow regimes, momentum balance from a hindcast model of currents in the channel, forced by observed hourly winds and hydrographic data, was calculated. The along-channel balance was found to be between wind, which was eastward (i.e., equatorward), sea level tilt, which was westward (i.e., poleward), and Coriolis, which was westward if the wind was (1) intense west and east of the channel and was eastward if the wind was (2) weaker in the east. Wind condition 1 produced southward cross-channel flow in the midchannel, connected by eastward currents upstream (downstream) along the northern (southern) coast of the channel, while wind condition 2 produced northward cross-channel flow connected by cyclonic recirculation in the west and westward inflow in the east. It is suggested that the former corresponds to the dynamical balance that may occur in the upwelling flow mode, while the latter corresponds to the cyclonic circulation mode. 1