18 research outputs found
Large-amplitude internal waves benefit corals during thermal stress
Tropical scleractinian corals are particularly vulnerable to global warming as elevated sea surface temperatures (SSTs) disrupt the delicate balance between the coral host and their algal endosymbionts, leading to symbiont expulsion, mass bleaching and mortality. While satellite sensing of SST has proved a reliable predictor of coral bleaching at the regional scale, there are large deviations in bleaching severity and mortality on the local scale that are poorly understood. Here, we show that internal waves play a major role in explaining local coral bleaching and mortality patterns in the Andaman Sea. Despite a severe region-wide SST anomaly in May 2010, frequent upslope intrusions of cold sub-pycnocline waters due to breaking large-amplitude internal waves (LAIW) mitigated coral bleaching and mortality in shallow waters. In LAIW-sheltered waters, by contrast, bleaching-susceptible species suffered severe bleaching and total mortality. These findings suggest that LAIW benefit coral reefs during thermal stress and provide local refugia for bleaching-susceptible corals. LAIW are ubiquitous in tropical stratified waters and their swash zones may thus be important conservation areas for the maintenance of coral diversity in a warming climate. Taking LAIW into account can significantly improve coral bleaching predictions and provide a valuable tool for coral reef conservation and management
Sediment distribution on the inner continental shelf off Khao Lak (Thailand) after the 2004 Indian Ocean tsunami
Reproductive aspects of the flyingfish, Hirundichthys affinis from the Northeastern coastal waters of Brazil
Shell occupation by the land hermit crab Coenobita violascens (Anomura, Coenobitidae) from Phuket Island, Thailand
Sedimentary deposits left by the 2004 Indian Ocean tsunami on the inner continental shelf offshore of Khao Lak, Andaman Sea (Thailand)
Growth performance of Porites lutea in response to differential impact of large amplitude internal waves (LAIW)
Internal structure of event layers preserved on the Andaman Sea continental shelf, Thailand: tsunami vs. storm and flash-flood deposits
Tsunami, storm and flash-flood event layers, which have been deposited over
the last century on the shelf offshore Khao Lak (Thailand, Andaman Sea), are
identified in sediment cores based on sedimentary structures, grain size
compositions, Ti / Ca ratios and <sup>210</sup>Pb activity. Individual offshore
tsunami deposits are 12 to 30 cm in thickness and originate from the 2004
Indian Ocean Tsunami. They are characterized by (1) the appearance of sand
layers enriched in shells and shell debris and (2) the appearance of mud and
sand clasts. Storm deposits found in core depths between 5 and 82 cm could
be attributed to recent storm events by using <sup>210</sup>Pb profiles in
conjunction with historical data of typhoons and tropical storms. Massive
sand layers enriched in shells and shell debris characterize storm deposits.
The last classified type of event layer represents reworked flash-flood
deposits, which are characterized by a fining-upward sequence of muddy
sediment. The most distinct difference between storm and tsunami deposits is
the lack of mud and sand clasts, mud content and terrigenous material
within storm deposits. Terrigenous material transported offshore during the
tsunami backwash is therefore an important indicator to distinguish between
storm and tsunami deposits in offshore environments