BC3. Basque centre for climate change – Klima aldaketa ikergai

Klimagune Summer School Training Caravan Seminars UPV BC3

Seminario / Mintegia 21st of June

Seminar / Mintegia / Seminario
Past climate change recorded in polar ice cores.

Prof. Kumiko Goto-Azuma (National Institute of Polar Research, Tokyo, Japan)

ABSTRACT: Snow falls on polar ice sheets and ice caps deposits onto the snow layers underneath, which accumulated in previous years. Snow then gets buried and turns into ice due to the overburden pressure. During this process, atmosphere is incorporated in ice as air bubbles. Polar ice sheets and ice caps are thus frozen archives of the past snow and atmosphere. Ice cores, cylindrical ice drilled from ice sheets (as well as from ice caps or glaciers), have been retrieved from Antarctica, Arctic and high mountains in low-mid latitudes. They have provided us with invaluable information on the past climate and environment.

The National Institute of Polar Research in Japan, together with Japanese and overseas collaborators, has drilled ice cores in Antarctica, Greenland, and on Arctic ice caps. A 3035m deep ice core was recently recovered at Dome Fuji, Antarctica and various analyses are underway. The Dome Fuji core goes back to 700,000 years ago, and reveals climatic and environmental variations during the past seven glacial cycles. Japan has participated in international deep ice coring projects in Greenland (GRIP, NGRIP and NEEM). These cores record climatic and environmental changes during the past 120,000 years and indicate that surprisingly abrupt climate changes have taken place in the past. Shallow Arctic ice cores covering the last few hundred years have extended our knowledge on the spatial and temporal changes of climate and environment. At the seminar, I will introduce how the ice cores are analyzed, dated, and used as climate and environment proxies, and discuss about the past climate and environmental changes recorded in the polar ice cores.




Seminar / Mintegia / Seminario
Deep ice core drilling, polar ice-sheet flow and its implications for climate change.

Prof. Nobuiko Azuma Nagaoka - University of Technology (Japan) ,Department of Mechanical Engineering, Snow and Ice laborator

ABSTRACT: Ice cores provide not only palaeoclimate information on timescales from decades to hundreds of millennia, but also very important information on ice sheets dynamics that shows how fast the ice sheets flow. To understand the physical and mechanical properties of ice-sheet ice is of vital importance to predict the future ice sheet behavior due to the global warming. During the past two decades, several deep ice drilling projects have been conducted in Greenland and Antarctica. In Greenland the international projects recovered four deep ice cores at GRIP, GISP2, NGRIP and NEEM sites. In Antarctica ten deep ice cores were recovered which include Dome C, EPICA-Dronning Maud Land, and Dome Fuji cores. These ice cores show how closely climate and greenhouse gas concentrations were linked in the past, and demonstrate that very abrupt climate switches can occur. With the completion of major projects in Greenland and Antarctica, the international ice coring community is planning for the next few decades to obtain the oldest ice which goes back to 1.5 million years ago.

Japan has been collaborating with over 20 years on development of drilling techniques, logistics and physics and chemistry analyses of ice cores in Greenland and Antarctica. In this talk I will introduce the history of international drilling projects and some of the major scientific results relevant to ice sheet dynamics.





Bizkaia Aretoa, Abandoibarra 3, Bilbao, 21st of June, 12:00 Room Elhuyar


