Abrupt climate changes during the marine isotope stage 3 (MIS 3)

Abstract The climate in the North Atlantic Ocean during the Marine Isotope Stage 3 (MIS 3)—roughly between 80,000 years before present (B.P.) and 20,000 years B.P., within the last glacial period—is characterized by great instability, with opposing climate transitions including at least six colde...

Descripción completa

Detalles Bibliográficos
Autores principales: Agosta, Eduardo Andrés, Compagnucci, Rosa Hilda
Formato: Parte de libro
Lenguaje:Inglés
Publicado: Springer Earth System Sciences 2024
Materias:
CAMBIO CLIMATICO
OCEANO ATLANTICO
ISOTOPOS MARINOS
CIRCULACION OCEANICA
CIRCULACION ATMOSFERICA
Acceso en línea:https://repositorio.uca.edu.ar/handle/123456789/18052
Aporte de:
Repositorio Institucional de la Universidad Católica Argentina (UCA) de Universidad Católica Argentina
id I33-R139-123456789-18052
record_format dspace
spelling I33-R139-123456789-180522024-05-08T05:01:28Z Abrupt climate changes during the marine isotope stage 3 (MIS 3) Agosta, Eduardo Andrés Compagnucci, Rosa Hilda CAMBIO CLIMATICO OCEANO ATLANTICO ISOTOPOS MARINOS CIRCULACION OCEANICA CIRCULACION ATMOSFERICA Abstract The climate in the North Atlantic Ocean during the Marine Isotope Stage 3 (MIS 3)—roughly between 80,000 years before present (B.P.) and 20,000 years B.P., within the last glacial period—is characterized by great instability, with opposing climate transitions including at least six colder Heinrich (H) events and fourteen warmer Dansgaard–Oeschger (D-O) events. Periodic longer cooling cycles encompassing two D-O events and ending in a colder Heinrich episode occurred lasting about 10 to 15 ky each, known as the Bond cycle. Heinrich events occurred less frequently than D-O events. These were recurrent every 1.5 ky on average, while *10 ky elapsed between two H events. Neither of the two types of events is strictly periodical, however. After H events abrupt shifted to warmer climate, the D-O events followed immediately. During an H event, abnormally large amounts of rock debris transported by icebergs were deposited as layers at the bottom of the North Atlantic Ocean. The various theories on the causes include factors internal to the dynamics of ice sheets, and external factors such as changes in the solar flux and changes in the Atlantic Meridional Overturning Circulation (AMOC). The latter is the most robust hypothesis. At certain times, these ice sheets released large amounts of freshwater into the North Atlantic Ocean. Heinrich events are an extreme example of this, when the Laurentide ice sheet disgorged excessively large amounts of freshwater into the Labrador Sea in the form of icebergs. These freshwater dumps reduced ocean salinity enough to slow down deep-water formation and AMOC. Since AMOC plays an important role in transporting heat northward, a slowdown would cause the North Atlantic Ocean to cool. Later, as the addition of freshwater decreased, ocean salinity and deep-water formation increased and climate conditions recovered. During the D-O events, the high-latitude warming occurred abruptly (probably in decades to centuries), reaching temperatures close to interglacial conditions. Even though H and D-O events seemed to have been initiated in the North Atlantic Ocean, they had a global footprint. Global climate anomalies were consistent with a slowdown of AMOC and reduced ocean heat transport into the northern high latitudes. The bipolar pattern with warming conditions in the Northern Hemisphere (NH) and cooling in the Southern Hemisphere (SH) is discussed from the information published by various authors who have used the limited data available for the SH, and palaeoclimatic simulations obtained by numerical modelling. Results show that the SH mid-latitude anomalies presented much smaller magnitude than those of the NH. 2024-05-07T11:16:33Z 2024-05-07T11:16:33Z 2016 Parte de libro Agosta, E.A., Compagnucci, R.H. (2016). Abrupt climate changes during the marine isotope stage 3 (MIS 3). Postprint del capítulo publicado en: Gasparini, G., Rabassa, J., Deschamps, C., Tonni, E. (eds). Marine Isotope Stage 3 in Southern South America, 60 KA B.P.-30 KA B.P.. Springer Earth System Sciences. Springer, Cham. doi:10.1007/978-3-319-40000-6_5. Disponible en: https://repositorio.uca.edu.ar/handle/123456789/18052 9783319400006 (online) 9783319399980 (impreso) https://repositorio.uca.edu.ar/handle/123456789/18052 10.1007/978-3-319-40000-6_5 eng Acceso restringido http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Springer Earth System Sciences Gasparini, G., Rabassa, J., Deschamps, C., Tonni, E. (eds). Marine Isotope Stage 3 in Southern South America, 60 KA B.P.-30 KA B.P.. Springer Earth System Sciences. Springer, Cham.
institution Universidad Católica Argentina
institution_str I-33
repository_str R-139
collection Repositorio Institucional de la Universidad Católica Argentina (UCA)
language Inglés
topic CAMBIO CLIMATICO
OCEANO ATLANTICO
ISOTOPOS MARINOS
CIRCULACION OCEANICA
CIRCULACION ATMOSFERICA
spellingShingle CAMBIO CLIMATICO
OCEANO ATLANTICO
ISOTOPOS MARINOS
CIRCULACION OCEANICA
CIRCULACION ATMOSFERICA
Agosta, Eduardo Andrés
Compagnucci, Rosa Hilda
Abrupt climate changes during the marine isotope stage 3 (MIS 3)
topic_facet CAMBIO CLIMATICO
OCEANO ATLANTICO
ISOTOPOS MARINOS
CIRCULACION OCEANICA
CIRCULACION ATMOSFERICA
description Abstract The climate in the North Atlantic Ocean during the Marine Isotope Stage 3 (MIS 3)—roughly between 80,000 years before present (B.P.) and 20,000 years B.P., within the last glacial period—is characterized by great instability, with opposing climate transitions including at least six colder Heinrich (H) events and fourteen warmer Dansgaard–Oeschger (D-O) events. Periodic longer cooling cycles encompassing two D-O events and ending in a colder Heinrich episode occurred lasting about 10 to 15 ky each, known as the Bond cycle. Heinrich events occurred less frequently than D-O events. These were recurrent every 1.5 ky on average, while *10 ky elapsed between two H events. Neither of the two types of events is strictly periodical, however. After H events abrupt shifted to warmer climate, the D-O events followed immediately. During an H event, abnormally large amounts of rock debris transported by icebergs were deposited as layers at the bottom of the North Atlantic Ocean. The various theories on the causes include factors internal to the dynamics of ice sheets, and external factors such as changes in the solar flux and changes in the Atlantic Meridional Overturning Circulation (AMOC). The latter is the most robust hypothesis. At certain times, these ice sheets released large amounts of freshwater into the North Atlantic Ocean. Heinrich events are an extreme example of this, when the Laurentide ice sheet disgorged excessively large amounts of freshwater into the Labrador Sea in the form of icebergs. These freshwater dumps reduced ocean salinity enough to slow down deep-water formation and AMOC. Since AMOC plays an important role in transporting heat northward, a slowdown would cause the North Atlantic Ocean to cool. Later, as the addition of freshwater decreased, ocean salinity and deep-water formation increased and climate conditions recovered. During the D-O events, the high-latitude warming occurred abruptly (probably in decades to centuries), reaching temperatures close to interglacial conditions. Even though H and D-O events seemed to have been initiated in the North Atlantic Ocean, they had a global footprint. Global climate anomalies were consistent with a slowdown of AMOC and reduced ocean heat transport into the northern high latitudes. The bipolar pattern with warming conditions in the Northern Hemisphere (NH) and cooling in the Southern Hemisphere (SH) is discussed from the information published by various authors who have used the limited data available for the SH, and palaeoclimatic simulations obtained by numerical modelling. Results show that the SH mid-latitude anomalies presented much smaller magnitude than those of the NH.
format Parte de libro
author Agosta, Eduardo Andrés
Compagnucci, Rosa Hilda
author_facet Agosta, Eduardo Andrés
Compagnucci, Rosa Hilda
author_sort Agosta, Eduardo Andrés
title Abrupt climate changes during the marine isotope stage 3 (MIS 3)
title_short Abrupt climate changes during the marine isotope stage 3 (MIS 3)
title_full Abrupt climate changes during the marine isotope stage 3 (MIS 3)
title_fullStr Abrupt climate changes during the marine isotope stage 3 (MIS 3)
title_full_unstemmed Abrupt climate changes during the marine isotope stage 3 (MIS 3)
title_sort abrupt climate changes during the marine isotope stage 3 (mis 3)
publisher Springer Earth System Sciences
publishDate 2024
url https://repositorio.uca.edu.ar/handle/123456789/18052
work_keys_str_mv AT agostaeduardoandres abruptclimatechangesduringthemarineisotopestage3mis3
AT compagnuccirosahilda abruptclimatechangesduringthemarineisotopestage3mis3
_version_ 1807949503460802560

Ejemplares similares