{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/9811"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/9811","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Historical climate variability reconstructed from massive coral records in the western Indian Ocean","abstract":"Coral δ¹⁸O and Sr/Ca records from massive corals in the western Indian Ocean (WIO) are used to establish the heterogeneous distribution of warming rates across the tropical and subtropical regions and to investigate if it corresponds with that from instrumental sea surface temperatures (SSTs). The coral records correlate with instrumental data better on monthly time scales compared to annual time scales. Coral thermal stress was assessed by the Degree Heating Months (DHM) technique and even though the coral DHM aligns quite well with instrumental DHM, the values from coral data are generally 2-3 times greater in magnitude than the DHM values from instrumental data. It was found that the accumulated thermal stress, calculated from coral and instrumental data, for the majority of the tropical and subtropical WIO sites has been increasing since the 1970’s. From 1870 to 1995, both the tropics and the subtropics have been warming in general, although with different and varying rates as recorded by the coral and the instrumental SSTs. It was further revealed that both the tropical and the subtropical WIO warmed during the summer and winter periods during 1870-1995. On longer time scales, the relationship between the coral records in the WIO and climate indices showed a significant interannual variability approximately centered at periods 3-6 years, indicating a probable link with ENSO and IOD. The extent to which coral reefs from different sites in the WIO are prepared to survive climate change based on historical SST variability and intensity of warming rates are described. It could therefore be suggested that some corals may be more favoured to survive warming climate compared to others because corals in the WIO are located in different oceanographic conditions and experience different climatic variations.","abstract_html":"Coral δ¹⁸O and Sr/Ca records from massive corals in the western Indian Ocean (WIO) are used to establish the heterogeneous distribution of warming rates across the tropical and subtropical regions and to investigate if it corresponds with that from instrumental sea surface temperatures (SSTs). The coral records correlate with instrumental data better on monthly time scales compared to annual time scales. Coral thermal stress was assessed by the Degree Heating Months (DHM) technique and even though the coral DHM aligns quite well with instrumental DHM, the values from coral data are generally 2-3 times greater in magnitude than the DHM values from instrumental data. It was found that the accumulated thermal stress, calculated from coral and instrumental data, for the majority of the tropical and subtropical WIO sites has been increasing since the 1970’s. From 1870 to 1995, both the tropics and the subtropics have been warming in general, although with different and varying rates as recorded by the coral and the instrumental SSTs. It was further revealed that both the tropical and the subtropical WIO warmed during the summer and winter periods during 1870-1995. On longer time scales, the relationship between the coral records in the WIO and climate indices showed a significant interannual variability approximately centered at periods 3-6 years, indicating a probable link with ENSO and IOD. The extent to which coral reefs from different sites in the WIO are prepared to survive climate change based on historical SST variability and intensity of warming rates are described. It could therefore be suggested that some corals may be more favoured to survive warming climate compared to others because corals in the WIO are located in different oceanographic conditions and experience different climatic variations.","abstract_has_math":false,"creators":["Nicolas, Jean Vincent Arnaud"],"institution":"Department of Oceanography","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Reason, Chris","Zinke, Jens"],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012","date_published":"2012","updated_at":"2026-07-22T22:23:38Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/9811","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Reason, Chris","Zinke, Jens"]},{"key":"dc:creator","label":"Author","values":["Nicolas, Jean Vincent Arnaud"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-11-28T09:55:13Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-11-28T09:55:13Z"]},{"key":"dc:date.issued","label":"Date","values":["2012"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Oceanography"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Master Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["MSc"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/9811"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes bibliographical references."]},{"key":"dc:description.abstract","label":"Abstract","values":["Coral δ¹⁸O and Sr/Ca records from massive corals in the western Indian Ocean (WIO) are used to establish the heterogeneous distribution of warming rates across the tropical and subtropical regions and to investigate if it corresponds with that from instrumental sea surface temperatures (SSTs). The coral records correlate with instrumental data better on monthly time scales compared to annual time scales. Coral thermal stress was assessed by the Degree Heating Months (DHM) technique and even though the coral DHM aligns quite well with instrumental DHM, the values from coral data are generally 2-3 times greater in magnitude than the DHM values from instrumental data. It was found that the accumulated thermal stress, calculated from coral and instrumental data, for the majority of the tropical and subtropical WIO sites has been increasing since the 1970’s. From 1870 to 1995, both the tropics and the subtropics have been warming in general, although with different and varying rates as recorded by the coral and the instrumental SSTs. It was further revealed that both the tropical and the subtropical WIO warmed during the summer and winter periods during 1870-1995. On longer time scales, the relationship between the coral records in the WIO and climate indices showed a significant interannual variability approximately centered at periods 3-6 years, indicating a probable link with ENSO and IOD. The extent to which coral reefs from different sites in the WIO are prepared to survive climate change based on historical SST variability and intensity of warming rates are described. It could therefore be suggested that some corals may be more favoured to survive warming climate compared to others because corals in the WIO are located in different oceanographic conditions and experience different climatic variations."]},{"key":"dc:title","label":"Title","values":["Historical climate variability reconstructed from massive coral records in the western Indian Ocean"]}]}],"canonical_facts":{"dc:contributor.advisor":["Reason, Chris","Zinke, Jens"],"dc:creator":["Nicolas, Jean Vincent Arnaud"],"dc:date.accessioned":["2014-11-28T09:55:13Z"],"dc:date.available":["2014-11-28T09:55:13Z"],"dc:date.issued":["2012"],"dc:description":["Includes bibliographical references."],"dc:description.abstract":["Coral δ¹⁸O and Sr/Ca records from massive corals in the western Indian Ocean (WIO) are used to establish the heterogeneous distribution of warming rates across the tropical and subtropical regions and to investigate if it corresponds with that from instrumental sea surface temperatures (SSTs). The coral records correlate with instrumental data better on monthly time scales compared to annual time scales. Coral thermal stress was assessed by the Degree Heating Months (DHM) technique and even though the coral DHM aligns quite well with instrumental DHM, the values from coral data are generally 2-3 times greater in magnitude than the DHM values from instrumental data. It was found that the accumulated thermal stress, calculated from coral and instrumental data, for the majority of the tropical and subtropical WIO sites has been increasing since the 1970’s. From 1870 to 1995, both the tropics and the subtropics have been warming in general, although with different and varying rates as recorded by the coral and the instrumental SSTs. It was further revealed that both the tropical and the subtropical WIO warmed during the summer and winter periods during 1870-1995. On longer time scales, the relationship between the coral records in the WIO and climate indices showed a significant interannual variability approximately centered at periods 3-6 years, indicating a probable link with ENSO and IOD. The extent to which coral reefs from different sites in the WIO are prepared to survive climate change based on historical SST variability and intensity of warming rates are described. It could therefore be suggested that some corals may be more favoured to survive warming climate compared to others because corals in the WIO are located in different oceanographic conditions and experience different climatic variations."],"dc:identifier.uri":["http://hdl.handle.net/11427/9811"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Oceanography"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Historical climate variability reconstructed from massive coral records in the western Indian Ocean"],"dc:type":["Master Thesis"],"dc:type.qualificationlevel":["Masters"],"dc:type.qualificationname":["MSc"]},"updated_at":"2026-07-22T22:23:38Z"}