Rapid Arctic warming accelerated by Pacific and Atlantic oceans

The Arctic has warmed faster than the global average by a factor of two or more since the mid-20th century, a phenomenon known as the Arctic amplification. The recent temperature warming over the Arctic is strongly linked to a drastic reduction in sea ice extent since the 1970s. A longstanding mystery is that a pronounced Arctic warming occurred during the early 20th century when greenhouse gas radiative forcing was weak. Using observations and model simulations, a research team led by Drs. Tokinaga and Mukougawa has discovered that a concurrent interdecadal warming of the Pacific and Atlantic were the major driver of the early Arctic warming. The results are presented on May 30, 2017, online Early Edition of Proceedings of the National Academy of Sciences of the United States of America. Read here for more detail.

Tokinaga, H., S.-P. Xie, and H. Mukougawa, 2017: Early 20th-century Arctic warming intensified by Pacific and Atlantic multidecadal variability, Proceedings of the National Academy of Sciences of the United States of America, doi:10.1073/pnas.1615880114

Schematic of the early 20th-century Arctic warming

Workshop and summer school in Hanoi

The Second International Workshop on Extreme Weather in Changing Climate in the Maritime Continent and South-East Asian School on Tropical Atmospheric Science were held at the Hanoi University of Science–Vietnam National University in Hanoi, Vietnam from 23 to 27 August, 2016.

Masahiro Shozaki, Hiroaki Yoshioka, Dr Tokinaga and Dr Enomoto participated the workshop and school. Masahiro and Hiroaki presented a poster, titled “Influence of El Niño on Winter Climate of Japan” and “Ensemble Experiments of the Tropical Cyclone Genesis under Weak Coriolis Force” respectively during the workshop. Dr Tokinaga  discussed “Patterns and influence of tropical ocean warming: Observations and simulations” as the final talk of the workshop. Dr Enomoto gave a talk on “Application of ensemble-based techniques to tropical disturbances” for the workshop and he also gave al ecture on “Introduction to numerical weather prediction” for the school.