scholarly journals NATIONAL NONTIDAL SEA LEVEL FORECASTS ON A COASTAL WAVEGUIDE

2020 ◽  
pp. 26
Author(s):  
Andy Taylor ◽  
Diana Greenslade ◽  
Xiaobing Zhou ◽  
Gary Brassington
Keyword(s):  
Sea Level ◽  
Trapped Waves ◽  
Forecast Data ◽  
Ordered Array ◽  
Forecast Models ◽  
Model Independent ◽  
Per Se ◽  
Coastally Trapped Waves

An approach to reduce gridded forecast data to novel waveguide coordinates is demonstrated; informed by the literature on coastally trapped waves. This does not produce new forecasts per se, but reduces data to a useful model-independent physically ordered array. Discussion is limited to the Australian mainland and forecast systems currently maintained in national operations. Heterogenous forecast models are considered with regard to the development of "seamless" sea level services across timescales.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/jlJO_dxHwuw

scholarly journals Sea Level Anomaly Forecasts on a Coastal Waveguide

2020 ◽  
Vol 35 (2) ◽  
pp. 757-770
Author(s):  
Andy Taylor ◽  
Gary B. Brassington
Keyword(s):  
Sea Level ◽  
Propagation Distance ◽  
Sea Level Anomaly ◽  
Remote Forcing ◽  
Forecast Data ◽  
Oceanographic Research ◽  
Forecast Models ◽  
Coastal Boundary ◽  
One Year ◽  
Coastally Trapped Waves

Abstract An approach to reduce forecast data to coastal waveguide coordinates is described and demonstrated, informed by the literature on coastally trapped waves (CTWs). All discussion is limited to the Australian mainland but the approach is generally relevant to regions where CTWs influence sea level, including the Americas and Africa. The approach does not produce new forecasts, but aims to focus forecaster attention on aspects of sea level forecasts prominent on the long Australian coast. The approach also explicitly addresses spatial issues associated with measuring coastal paths. Coastal paths are scale dependent and forecast models discretize the coastal boundary differently. A well-defined coastal path is required for the quantitative application of CTW concepts such as propagation distance and offshore direction. The relevance of coastally trapped signals and remote forcing is documented in the oceanographic literature, but is effectively unknown to the general public and rarely mentioned in press reports of sea level events such as nuisance flooding. Routine presentation of forecast guidance in waveguide coordinates could contribute to the transfer of oceanographic research understanding into forecast narratives. In addition, the approach can facilitate quantitative forecast evaluations that target CTW properties. Two ocean forecast systems are contrasted in this framework for the Australian mainland. One year of daily forecasts are compared, with indications that model baroclinicity is of practical relevance.

scholarly journals Sea Level and the Role of Coastal Trapped Waves in Mediating the Influence of the Open Ocean on the Coast

2019 ◽  
Vol 40 (6) ◽  
pp. 1467-1492 ◽  
Author(s):  
Chris W. Hughes ◽  
Ichiro Fukumori ◽  
Stephen M. Griffies ◽  
John M. Huthnance ◽  
Shoshiro Minobe ◽  
...  
Keyword(s):  
Sea Level ◽  
Open Ocean ◽  
Trapped Waves ◽  
Coastal Trapped Waves

Currents off south-eastern Australia: results from the Australian coastal experiment

1988 ◽  
Vol 39 (3) ◽  
pp. 245 ◽  
Author(s):  
A Huyer ◽  
RL Smith ◽  
PJ Stabeno ◽  
JA Church ◽  
NJ White
Keyword(s):  
Sea Level ◽  
Continental Slope ◽  
Wind Stress ◽  
Continental Margin ◽  
Eddy Currents ◽  
Empirical Orthogonal Functions ◽  
Trapped Waves ◽  
Orthogonal Functions ◽  
Coastal Trapped Waves ◽  
And Sea Level

The Australian Coastal Experiment was conducted off the east coast of New South Wales between September 1983 and March 1984. The experiment was conducted with arrays of current meters spanning the continental margin at three latitudes (37.5�, 34.5�, and 33.0�S.), additional shelf moorings at 29� and 42�S. coastal wind and sea-level measurements, monthly conductivity-temperature-depth probe/expendable bathythermograph (CTD/XBT) surveys, and two satellite-tracked buoys. Over the continental shelf and slope, the alongshore component of the current generally exceeded the onshore component, and the subtidal (<0.6 cpd, cycles per day) current variability greatly exceeded the mean flow. Part of the current variability was associated with two separate warm-core eddies that approached the coast, causing strong (>50 cm sec-1), persistent (>8 days), southward currents over the continental slope and outer shelf. Temperature and geostrophic velocity sections through the eddies, maps of ship's drift vectors and temperature contours at 250 m, and the satellite-tracked drifter trajectories showed that these eddies were similar in structure to those observed previously in the East Australian Current region. Both eddies migrated generally southward. Eddy currents over the shelf and slope were rare at Cape Howe (37.5�S.), more common near Sydney (34.5�S.), and frequent at Newcastle (33.0�S.), where strong northward currents were also observed. Near Sydney, the eddy currents over the slope turned clockwise with depth between 280 and 740 m, suggesting net downwelling there. Repeated CTD sections also indicated onshore transport and downwelling at shallower levels; presumably, upwelling occurred farther south where the eddy currents turned offshore. Periodic rotary currents over the continental slope near Sydney and Newcastle indicated the presence of small cyclonic eddies on the flank of a much larger anticyclonic eddy. Between early October and late January, no strong southward currents were observed over the continental margin near Sydney. Data from this 'eddy-free' period were analysed further to examine the structure and variability of the coastal currents. Much of this variability was correlated with fluctuations in coastal sea-level (at zero lag) and with the wind stress (at various lags). The coherence and phase relationships among current, wind-stress, and sea-level records at different latitudes (determined from spectral analysis and frequency-domain empirical orthogonal functions) were consistent with the equatorward propagation of coastal-trapped waves generated by winds in phase with those near Cape Howe. Time-domain empirical orthogonal functions show that the current fluctuations decayed with distance from shore and with depth, as expected of coastal-trapped waves.

Coronary lipid deposition during chronic anemia or high altitude exposure

1961 ◽  
Vol 16 (1) ◽  
pp. 103-106 ◽  
Author(s):  
Louis C. Fillios ◽  
Stephen B. Andrus ◽  
Chikayuki Naito
Keyword(s):  
High Altitude ◽  
Sea Level ◽  
Prolonged Exposure ◽  
Tissue Hypoxia ◽  
Lipid Deposition ◽  
High Altitudes ◽  
Chronic Anemia ◽  
Apparent Increase ◽  
Altitude Exposure ◽  
Per Se

Experimental anemia and polycythemia were studied in hypercholesteremic rats. The following results were noted: a) chronic anemia favors a significant increase in endocardial and coronary lipid deposition; b) rats made polycythemic by prolonged exposure to simulated high altitudes also had a marked degree of coronary involvement but no apparent increase in endocardial sudanophilia; whereas c) sea-level cobalt polycythemia does not appear to favor an increase in coronary or endocardial sudanophilia, suggesting that d) polycythemia, per se, does not favor an increase in lipid deposition at these sites. These findings suggest that tissue hypoxia may account for the above increases in coronary sudanophilia, while changes in endocardial sudanophilia appear to be related more closely to the circulating cholesterol for all the groups. Submitted on May 16, 1960

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