New Evidence for the Holocene Sea-Level High from the Inner Shelf, Central Great Barrier Reef, Australia

Weather and currents at eight sites were measured and drogue trajectories obtained in July 1979 at Britomart Reef, a middle reef located at 18�16'S.,146� 38'E. in the central region of the Great Barrier Reef province. The longest current records (3 weeks) were obtained at two sites in passes between the Coral Sea and the Great Barrier Reef Lagoon where westerly currents modulated by tides were observed. Analysis of residuals also showed the importance of wind-driven secondary circulation. Non-tidal sea-level oscillations were very small. Shorter current records (1-10 days) at six sites in the lagoon and on the reef flat showed a predominant northerly flow, also modulated by tides and wind. A residual anticlockwise water circulation existed in the lagoon where flushing was controlled more by winds than by tides. The rise in sea level over the reef flat as a result of waves breaking was negligible. Temperature differences between air and water accounted for the cooling of the water column during the expedition. Constant south-east trade winds were experienced at the reef, while on land the wind was weaker. more variable, and often dominated by land-sea breezes.

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Forty-five years of change on low wooded islands, Great Barrier Reef

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1978.0053 ◽

1978 ◽

Vol 284 (999) ◽

pp. 63-80 ◽

Cited By ~ 18

Keyword(s):

Great Barrier Reef ◽

Coral Growth ◽

Barrier Reef ◽

Evolutionary Sequence ◽

The Holocene ◽

Additional Information ◽

Aerial Reconnaissance ◽

History Of ◽

Barrier Reefs

During the 1928-29 Expedition, centred at Low Isles, Spender mapped the ‘low wooded islands’ or ‘island-reefs’ of Low Isles and Three Isles in detail, and additional information was published by Steers, T. A. Stephenson and others. From this work, two different models of the evolution of low wooded islands were proposed, Spender holding that the islands were in a state of equilibrium resulting from their location on the reef, Steers that they could be placed in an evolutionary sequence. Moorhouse described the results of cyclones at Low Isles in 1931 and 1934, and Fairbridge & Teichert reconsidered the general issues following aerial reconnaissance and a brief visit to Low Isles in 1945. Subsequently, aspects of change since 1928-29 have been studied at Low Isles by W. Stephenson, Endean & Bennett in 1954 and by W. Macnae in 1965. Maps produced since 1929, however, have all been based on Spender’s surveys. In 1973, Low Isles and Three Isles were remapped in detail, and a direct comparison can now be made over an interval of 45 years. This shows changes in island topography, and substantial alteration in the size and location of shingle ramparts which has affected conditions for coral growth on reef flats. Mangroves have extended greatly at Low Isles, but not at all at Three Isles. The implications of these findings for the general models of Steers and Spender will be discussed and related to the Holocene history of the Great Barrier Reefs.

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New evidence for “far-field” Holocene sea level oscillations and links to global climate records

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2018.02.008 ◽

2018 ◽

Vol 487 ◽

pp. 67-73 ◽

Cited By ~ 9

Author(s):

N.D. Leonard ◽

K.J. Welsh ◽

T.R. Clark ◽

Y.-x. Feng ◽

J.M. Pandolfi ◽

...

Keyword(s):

Sea Level ◽

Global Climate ◽

Far Field ◽

Climate Records ◽

Sea Level Oscillations ◽

New Evidence ◽

Holocene Sea Level

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Water circulation and shelf waves in the northern Great Barrier Reef lagoon

Marine and Freshwater Research ◽

10.1071/mf9810721 ◽

1981 ◽

Vol 32 (5) ◽

pp. 721 ◽

Cited By ~ 25

Author(s):

E Wolanski ◽

B Ruddick

Keyword(s):

Great Barrier Reef ◽

Sea Level ◽

Low Frequency ◽

Current Data ◽

Barrier Reef ◽

Sea Levels ◽

The North ◽

Level Data ◽

Shelf Wave ◽

Salinity Water

Currents and sea levels were measured at a number of locations in the Great Barrier Reef (GBR) lagoon from about 10 to 13� S., during the period October-December 1979. A strong non-tidal, low-frequency modulation of all sea-level and current data was found. The currents nearshore were driven northward by the wind, and then at least partially blocked by the dense network of reefs to the north of 10� s. The water then flowed southward in deeper water adjacent to the reef, driven by a longshore pressure gradient. The low- frequency sea-level data, though not the current records, showed northward phase propagation at speeds characteristic of a first-mode shelf wave trapped in the lagoon between the shore and the reef. Data are presented revealing the intrusion of low-salinity water, through Bligh Entrance, in the GBR lagoon, as a result of river discharges in the Gulf of Papua. It is suggested that low-frequency longshore currents may periodically flush these river plumes from the GBR lagoon and enhance interaction between reefs. In the Coral Sea in front of reef passages, the large horizontal velocities may result in forces upwelling by selective withdrawal and jet entrainment.

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Continental shelf waves and their influence on the circulation around the Great Barrier Reef

Marine and Freshwater Research ◽

10.1071/mf9830023 ◽

1983 ◽

Vol 34 (1) ◽

pp. 23 ◽

Cited By ~ 24

Author(s):

E Wolanski ◽

AF Bennett

Keyword(s):

Continental Shelf ◽

Great Barrier Reef ◽

Sea Level ◽

Atmospheric Pressure ◽

Low Frequency ◽

Internal Tides ◽

Wind Component ◽

Barrier Reef ◽

Longshore Current ◽

Shelf Waves

Winds and atmospheric pressure, sea level and water currents were measured at several locations over the continental shelf, both east and west of the Great Barrier Reef, between 14.5�s. and 20�S., from June to November 1980. The dominant wind direction changed from westward over the Coral Sea to north- westward (roughly parallel to the shore) over the shelf. A strong non-tidal low-frequency signal in all sea- level and longshore current data was found, highly coherent from site to site and strongly correlated with the longshore wind component over the shelf, though not with the atmospheric pressure. A model of wind- driven barotropic shelf waves is used to explain a number of observations, such as the invariance of temporal fluctuations of longshore current with distance from shore, and the northward longshore propagation of oceanic disturbances at a speed equal to twice that of the first-mode barotropic free shelf wave, a speed one order of magnitude smaller than that of the wind system. The low-frequency current fluctuations resulted in large water displacements, up and down the coast. Low-frequency cross-shelf currents were much weaker and less coherent. Two upwelling mechanisms are internal tides and internal Kelvin waves coupled to the barotropic shelf waves.

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