Press release with author’s message
— From ArCS II News Letter No.9 —
In ArCS II Newsletter No.9, the authors of articles published in 2023 fall and 2024 spring contributed their research, thoughts on their research, and future prospects.
*Affiliations are at the time of the newsletter publication.
Unusually Low Oxygen and Acidified Water Found in the Arctic High Seas
Shigeto Nishino
(Institute of Arctic Climate and Environment Research, JAMSTEC)
The 2020 ship-based observations of the international Synoptic Arctic Survey (SAS) project have discovered unusually low oxygen and acidified water on a plateau on the Pacific side of the Arctic high seas. This water, which had previously been found only along the Siberian coast, was transported to the plateau further north due to changes in ocean circulation associated with the recent sea-ice loss. Since this area is experiencing the fastest ocean hypoxia and acidification in the high seas of the Arctic Ocean, there is concern about the impact on the marine ecosystem.
| Title | Atlantic-origin water extension into the Pacific Arctic induced an anomalous biogeochemical event |
| Journal | Nature Communications |
| Published | November 2, 2023 |
| Authors | Shigeto Nishino, Jinyoung Jung, Kyoung-Ho Cho, William J. Williams, Amane Fujiwara, Akihiko Murata, Motoyo Itoh, Eiji Watanabe, Michio Aoyama, Michiyo Yamamoto-Kawai, Takashi Kikuchi, Eun Jin Yang, Sung-Ho Kang |
| DOI | https://doi.org/10.1038/s41467-023-41960-w |
Press Release
Automated Detection of Supraglacial Lake Evolution Using Remote Sensing and Machine Learning
Yefan Wang
(School of GeoSciences, The University of Edinburgh
Institute of Low Temperature Science, Hokkaido University *at the time of press release)
Supraglacial lakes are formed by the accumulation of meltwater, which is thought to accelerate the melting and flow of ice. We investigated the formation and distribution of supraglacial lakes in northwestern Greenland by analyzing satellite images using machine learning methods. The results revealed that the frequency of lake formation is influenced by the topography and ice velocity of the glaciers and that the total lake area expands in years when strong melting is enhanced by high summer temperatures. This finding is significant for understanding future ice sheet dynamics and suggests a trend of lake expansion inland due to climate warming.
| Title | Supraglacial lake evolution on Tracy and Heilprin Glaciers in northwestern Greenland from 2014 to 2021 |
| Journal | Remote Sensing of Environment |
| Published | March 15, 2024 |
| Authors | Yefan Wang, Shin Sugiyama |
| DOI | https://doi.org/10.1016/j.rse.2024.114006 |
Press Release（only in Japanese）
Jet Stream Meandering is Enhanced by Coupling with Extratropical Ocean and Sea Ice
Masato Mori
(Research Institute for Applied Mechanics, Kyushu University)
Teleconnection patterns are atmospheric circulation patterns recurrent in the same region and closely related to abnormal weather in that region. Their generation and maintenance mechanisms have been extensively investigated. However, the role of extratropical oceans remains unclear. In this study, we conducted a large number of numerical simulations and discovered that the coupling between the atmosphere, ocean, and sea ice in the extratropics enhances the variability of teleconnection patterns (i.e., the variability of the meandering and strengthening of westerly winds), elucidating the underlying mechanisms.
| Title | Northern Hemisphere winter atmospheric teleconnections are intensified by extratropical ocean-atmosphere coupling |
| Journal | Communications Earth & Environment |
| Published | March 15, 2024 |
| Authors | Masato Mori, Yu Kosaka, Bunmei Taguchi, Hiroki Tokinaga, Hiroaki Tatebe, Hisashi Nakamura |
| DOI | https://doi.org/10.1038/s43247-024-01282-1 |
Press Release
Tracing the Footprint of Atmospheric Methane Using Isotope Model
Naveen Chandra
(Institute of Arctic Climate and Environment Research, JAMSTEC)
We reproduce the atmospheric methane (CH4) and its isotope ratio for the last 30 years (1990-2020) using the ACTM model to trace footprints of fossil fuel (FF) and microbial sources to its long-term change. Our analysis reveals that CH4 emissions from FF leaks decreased from 1990s to the early 2000s and have since stabilized, whereas emissions from microbial sources have steadily increased due to more cattle-rearing and larger waste dump areas. While reducing FF emissions remains crucial, our findings underscore the importance of targeting microbial emissions to achieve the global CH4 emission reduction goals outlined in the Global Methane Pledge.
| Title | Methane emissions decreased in fossil fuel exploitation and sustainably increased in microbial source sectors during 1990–2020 |
| Journal | Communications Earth ＆ Environment |
| Published | April 17, 2024 |
| Authors | Naveen Chandra, Prabir K. Patra, Ryo Fujita, Lena Höglund-Isaksson, Taku Umezawa, Daisuke Goto, Shinji Morimoto, Bruce H. Vaughn, Thomas Röckmann |
| DOI | https://doi.org/10.1038/s43247-024-01286-x |
Press Release