Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis )

분야Field	2018 Math Colloquium
날짜Date	2018-03-30 ~ 2018-03-30	시간Time	15:50 ~ 18:00
장소Place	Math. Bldg. 404	초청자Host	Yong-Geun Oh
연사Speaker	Axel Timmermann	소속Affiliation	IBS for Climate Physics
TOPIC	Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis )
소개 및 안내사항Content	Title: Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis ) Abstract: Dansgaard Oeschger (DO) events are one of the most fascinating phenomena in our climate system. They are characterized by rapid [(10 years)] warming of the Northern Hemisphere reaching values of about 4oC and a gradual temperature decline that can last up to several thousand years. These events preferably occurred during glacial periods, when North America and Eurasia were partly covered by massive ice sheets. Unraveling the underlying mechanisms of DO events has been a major challenge and it requires a concerted multi-disciplinary effort, which has involved glaciologists, oceanographers, climate modelers and mathematicians. In this presentation I will report on my personal 15-year long journey to understand these peculiar climatic events. It started with a Dynamical Systems’ approach and the discovery that climate oscillations, that bear quite some similarity to the observed DO events, can be simulated in a simplified climate model through a mechanism referred to as “Coherence Resonance”. According to this scenario, DO-type events originate from the interaction of the Atlantic Ocean circulation and polar sea ice. 5 years ago, my principal understanding of these events was shattered when new paleoceanographic data became available that demonstrate that in fact instabilities of the Scandinavian ice-sheet may have contributed to the generation of these climatic transitions. Using an earth system model of intermediate complexity my team and I developed a new model simulation that can reproduce all observed DO events from 50-30,000 years ago, if we apply the reconstructed Eurasian ice-sheet variations as a freshwater forcing to the North Atlantic. I will discuss this new solution in the light of new paleo-climate data from the North Atlantic region, the deep Southern Ocean, Monsoon regions and the North Pacific.

학회명Field	Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis )
날짜Date	2018-03-30 ~ 2018-03-30	시간Time	15:50 ~ 18:00
장소Place	Math. Bldg. 404	초청자Host	Yong-Geun Oh
소개 및 안내사항Content	Title: Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis ) Abstract: Dansgaard Oeschger (DO) events are one of the most fascinating phenomena in our climate system. They are characterized by rapid [(10 years)] warming of the Northern Hemisphere reaching values of about 4oC and a gradual temperature decline that can last up to several thousand years. These events preferably occurred during glacial periods, when North America and Eurasia were partly covered by massive ice sheets. Unraveling the underlying mechanisms of DO events has been a major challenge and it requires a concerted multi-disciplinary effort, which has involved glaciologists, oceanographers, climate modelers and mathematicians. In this presentation I will report on my personal 15-year long journey to understand these peculiar climatic events. It started with a Dynamical Systems’ approach and the discovery that climate oscillations, that bear quite some similarity to the observed DO events, can be simulated in a simplified climate model through a mechanism referred to as “Coherence Resonance”. According to this scenario, DO-type events originate from the interaction of the Atlantic Ocean circulation and polar sea ice. 5 years ago, my principal understanding of these events was shattered when new paleoceanographic data became available that demonstrate that in fact instabilities of the Scandinavian ice-sheet may have contributed to the generation of these climatic transitions. Using an earth system model of intermediate complexity my team and I developed a new model simulation that can reproduce all observed DO events from 50-30,000 years ago, if we apply the reconstructed Eurasian ice-sheet variations as a freshwater forcing to the North Atlantic. I will discuss this new solution in the light of new paleo-climate data from the North Atlantic region, the deep Southern Ocean, Monsoon regions and the North Pacific.

성명Field	Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis )
날짜Date	2018-03-30 ~ 2018-03-30	시간Time	15:50 ~ 18:00
소속Affiliation	IBS for Climate Physics	초청자Host	Yong-Geun Oh
소개 및 안내사항Content	Title: Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis ) Abstract: Dansgaard Oeschger (DO) events are one of the most fascinating phenomena in our climate system. They are characterized by rapid [(10 years)] warming of the Northern Hemisphere reaching values of about 4oC and a gradual temperature decline that can last up to several thousand years. These events preferably occurred during glacial periods, when North America and Eurasia were partly covered by massive ice sheets. Unraveling the underlying mechanisms of DO events has been a major challenge and it requires a concerted multi-disciplinary effort, which has involved glaciologists, oceanographers, climate modelers and mathematicians. In this presentation I will report on my personal 15-year long journey to understand these peculiar climatic events. It started with a Dynamical Systems’ approach and the discovery that climate oscillations, that bear quite some similarity to the observed DO events, can be simulated in a simplified climate model through a mechanism referred to as “Coherence Resonance”. According to this scenario, DO-type events originate from the interaction of the Atlantic Ocean circulation and polar sea ice. 5 years ago, my principal understanding of these events was shattered when new paleoceanographic data became available that demonstrate that in fact instabilities of the Scandinavian ice-sheet may have contributed to the generation of these climatic transitions. Using an earth system model of intermediate complexity my team and I developed a new model simulation that can reproduce all observed DO events from 50-30,000 years ago, if we apply the reconstructed Eurasian ice-sheet variations as a freshwater forcing to the North Atlantic. I will discuss this new solution in the light of new paleo-climate data from the North Atlantic region, the deep Southern Ocean, Monsoon regions and the North Pacific.

성명Field	Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis )
날짜Date	2018-03-30 ~ 2018-03-30	시간Time	15:50 ~ 18:00
호실Host		인원수Affiliation	Axel Timmermann
사용목적Affiliation	Yong-Geun Oh	신청방식Host	IBS for Climate Physics
소개 및 안내사항Content	Title: Climate Complexity( A journey into ocean mud, ice cores, supercomputing and bifurcation analysis ) Abstract: Dansgaard Oeschger (DO) events are one of the most fascinating phenomena in our climate system. They are characterized by rapid [(10 years)] warming of the Northern Hemisphere reaching values of about 4oC and a gradual temperature decline that can last up to several thousand years. These events preferably occurred during glacial periods, when North America and Eurasia were partly covered by massive ice sheets. Unraveling the underlying mechanisms of DO events has been a major challenge and it requires a concerted multi-disciplinary effort, which has involved glaciologists, oceanographers, climate modelers and mathematicians. In this presentation I will report on my personal 15-year long journey to understand these peculiar climatic events. It started with a Dynamical Systems’ approach and the discovery that climate oscillations, that bear quite some similarity to the observed DO events, can be simulated in a simplified climate model through a mechanism referred to as “Coherence Resonance”. According to this scenario, DO-type events originate from the interaction of the Atlantic Ocean circulation and polar sea ice. 5 years ago, my principal understanding of these events was shattered when new paleoceanographic data became available that demonstrate that in fact instabilities of the Scandinavian ice-sheet may have contributed to the generation of these climatic transitions. Using an earth system model of intermediate complexity my team and I developed a new model simulation that can reproduce all observed DO events from 50-30,000 years ago, if we apply the reconstructed Eurasian ice-sheet variations as a freshwater forcing to the North Atlantic. I will discuss this new solution in the light of new paleo-climate data from the North Atlantic region, the deep Southern Ocean, Monsoon regions and the North Pacific.