Article
Environmental Sciences
Miao Yu, Peng Lu, Bin Cheng, Matti Leppaeranta, Zhijun Li
Summary: This study investigates the impact of the microstructure of summer sea ice on its optical properties. Gas bubbles are found to be the main scatterers within sea ice and have a much stronger effect on scattering coefficient and ice albedo compared to brine pockets. Additionally, higher concentration and larger size of particulate matter particles lead to decreased ice albedo and transmittance. The microstructure of ice plays a more significant role in radiation transfer partitioning in seasonal ice compared to multiyear ice, and in ponded ice compared to snow-covered ice.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Shaoyin Wang, Jiping Liu, Xinyu Li, Yufang Ye, Richard J. Greatbatch, Zhuoqi Chen, Xiao Cheng
Summary: The Greenland high has a significant influence on Greenland ice sheet melting and summer Arctic sea ice. In this study, it is found that an intensified Greenland high in early summer leads to a decline in sea ice concentration and thickness over the Beaufort Sea. This decline is primarily due to thermodynamic and mechanical redistribution processes. The intensified Greenland high increases subsidence over the Canadian Basin and easterly wind frequency over the Beaufort Sea, pushing the sea ice away from the coastlines and resulting in increased open water areas.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Microbiology
Stefan Thiele, Julia E. Storesund, Mar Fernandez-Mendez, Philipp Assmy, Lise Ovreas
Summary: The Arctic is warming at a rate 2-3 times faster than the global average, leading to changes in Arctic sea ice and impacting ice-associated ecosystems. Sea-ice algal blooms play a crucial role in driving the succession of bacterial and archaeal communities in Arctic sea ice.
Article
Environmental Sciences
Jong -Min Kim, Sang -Woo Kim, Byung-Ju Sohn, Hyun-Cheol Kim, Sang-Moo Lee, Young-Joo Kwon, Hoyeon Shi, Andrey V. Pnyushkov
Summary: A method was developed to estimate pan-Arctic ice draft using spaceborne passive microwave measured brightness temperatures. The method was validated using upward-looking sonar measurements and ice mass balance buoy measurements. The results showed good agreement between the estimated ice draft and the measurements, suggesting the robustness of the estimation method.
REMOTE SENSING OF ENVIRONMENT
(2023)
Article
Meteorology & Atmospheric Sciences
Qifeng Qian, Xiaojing Jia, Renguang Wu, Min Wang
Summary: This study investigates the impact of interannual variation in autumn Arctic sea ice concentration on early winter precipitation over nonmonsoonal Eurasian regions through observations and numerical model experiments. It is found that negative autumn sea ice anomalies induce heating in the overlying atmosphere and excite a Rossby wave that propagates from the Beaufort-Chukchi-East Siberian Seas (BCES) through the Atlantic Ocean to Eurasia. The wave obtains energy from the mean flow, with baroclinic energy conversion being more important. Anomalous cyclone and anticyclone associated with the Rossby wave result in positive precipitation anomalies over southern Europe and negative anomalies over central Asia and the west Siberian plain.
JOURNAL OF CLIMATE
(2023)
Article
Geosciences, Multidisciplinary
Lars Aue, Timo Vihma, Petteri Uotila, Annette Rinke
Summary: Based on the ERA5 reanalysis, this study examines the impacts of transient cyclones on sea ice concentration (SIC) in the Atlantic sector of the Arctic Ocean under New Arctic conditions (2000-2020). The results show a pattern of reduced SIC prior to and during cyclones for the entire study area, with a regional difference of increased SIC in the Barents Sea and reduced SIC in the Greenland Sea from 3 days before to 5 days after the cyclone passage. The study suggests that both thermodynamic and dynamic effects contribute to the SIC changes, particularly in the Barents Sea, compared to the Old Arctic (1979-1999).
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Jingwen Zeng, Qinghua Yang, Xuewei Li, Xiaojun Yuan, Mitchell Bushuk, Dake Chen
Summary: This study investigates the potential influence of surface heat flux, cloud, and water vapor anomalies on the monthly to seasonal predictions of Arctic sea ice concentration (SIC) anomalies. The results show that models using surface fluxes, clouds, or water vapor in combination with SIC and surface sea temperature as predictors can enhance the skill in predicting Arctic September SIC when initialized in spring. This suggests that including the surface heat budget has the potential to reduce the spring barrier for Arctic SIC predictions.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Hong-Li Ren, Yu Nie
Summary: This study developed a linear empirical model using two effective precursors significantly correlated with the winter Arctic Oscillation (WAO) in the Northern Hemisphere, achieving skillful predictions with a lead time of about half a year. The stable precursor signals extracted from anomalies of the Arctic sea ice concentration and tropical sea surface temperature enable the model to outperform dynamical models in predicting WAO.
SCIENCE CHINA-EARTH SCIENCES
(2021)
Article
Meteorology & Atmospheric Sciences
Jennifer Lukovich, Julienne C. Stroeve, Alex Crawford, Lawrence Hamilton, Michel Tsamados, Harry Heorton, Francois Massonnet
Summary: The study investigates the impact of extreme cyclones on Arctic sea ice in summer, focusing on the thermodynamic and dynamic contributions to sea ice volume budgets in 2012 and 2016. Results show that sea ice loss in the vicinity of cyclones in these two years was associated with different dominant processes, and the timing and location of the cyclones also play a key role in influencing Arctic sea ice extent.
JOURNAL OF CLIMATE
(2021)
Article
Geography, Physical
William Gregory, Julienne Stroeve, Michel Tsamados
Summary: The indirect effect of winter Arctic Oscillation events on summer Arctic sea ice extent suggests a mechanism for sea ice predictability from winter to summer. However, current coupled climate models show a decrease in predictive skill for summer sea ice forecasts, indicating that some long-term drivers of sea ice variability are not well represented in these models.
Article
Environmental Sciences
Tianyi Sun, Ilissa B. Ocko, Steven P. Hamburg
Summary: This study explores the value of early methane mitigation in addition to carbon dioxide mitigation in helping prevent the loss of Arctic summer sea ice. It shows that simultaneous deployment of feasible methane mitigation measures is essential in controlling the fate of Arctic summer sea ice. The benefit of combined methane and carbon dioxide mitigation can be greater than the sum of their independent benefits.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Peng Zhang, Zhiwei Wu, Rui Jin
Summary: The study found that the early summer precipitation variability in Northeast Asia is not fully understood, but may be related to the North Atlantic Oscillation and the Barents Sea ice cover. During negative NAO winters, anomalous northerlies increase local sea ice, leading to geopotential height anomalies that result in rich rainfall in southern NEA. Conversely, there may be reduced precipitation in northern NEA due to lower-level divergence.
Article
Environmental Sciences
Xiao Zhou, Bin Wang, Fei Huang
Summary: The rapid decline of Arctic sea ice is a clear indication of global climate change. Existing evaluation metrics are insufficient, leading to the proposal of two new metrics based on sea ice thickness. Good models project the first ice-free year in the Arctic to be 2049.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Marko Makynen, Markku Simila
Summary: ATIDA2 is a thin ice detection algorithm developed for AMSR2 radiometer data, which uses various signature features for discrimination between thin and thick ice in the Arctic Ocean. The algorithm is applied under specific conditions to reduce misclassification of thick ice as thin ice. The average probability for misclassification in the daily chart is relatively low, showcasing the accuracy of ATIDA2 in ice classification.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Environmental Sciences
Lei Zheng, Xiao Cheng, Zhuoqi Chen, Qi Liang
Summary: The study examines the relationship between sea ice freeze-up timing and summer sea ice evolution through satellite-based observations, highlighting the impact of Arctic sea ice loss on the delay in autumn freeze-up. It reveals the physical mechanism behind this connection and emphasizes the importance of the ice-albedo feedback in the process.
Article
Meteorology & Atmospheric Sciences
Chuan-Yang Wang, Shang-Ping Xie, Yu Kosaka
JOURNAL OF CLIMATE
(2020)
Article
Multidisciplinary Sciences
Dillon J. Amaya, Arthur J. Miller, Shang-Ping Xie, Yu Kosaka
NATURE COMMUNICATIONS
(2020)
Article
Environmental Sciences
Jun-Chao Yang, Xiaopei Lin, Shang-Ping Xie, Yu Zhang, Yu Kosaka, Ziguang Li
NATURE CLIMATE CHANGE
(2020)
Article
Multidisciplinary Sciences
Patrick Martineau, Hisashi Nakamura, Yu Kosaka, Ayako Yamamoto
SCIENTIFIC REPORTS
(2020)
Article
Geosciences, Multidisciplinary
Hai Wang, Shang-Ping Xie, Xiao-Tong Zheng, Yu Kosaka, Yangyang Xu, Yu-Fan Geng
GEOPHYSICAL RESEARCH LETTERS
(2020)
Article
Meteorology & Atmospheric Sciences
Patrick Martineau, Hisashi Nakamura, Yu Kosaka, Bunmei Taguchi, Masato Mori
JOURNAL OF CLIMATE
(2020)
Article
Environmental Sciences
Masahiro Watanabe, Jean-Louis Dufresne, Yu Kosaka, Thorsten Mauritsen, Hiroaki Tatebe
Summary: The east-west gradient in equatorial Pacific sea surface temperature has strengthened since the mid-twentieth century, but models suggest a weakening of the gradient in past and future climates; internal climate variability may be driving the observed intensifying SST gradient, which is projected to reverse in the future according to models.
NATURE CLIMATE CHANGE
(2021)
Article
Meteorology & Atmospheric Sciences
Ayumu Miyamoto, Hisashi Nakamura, Takafumi Miyasaka, Yu Kosaka
Summary: The study reveals that low-level clouds play a crucial role in reinforcing the summertime Mascarene high by affecting sea surface temperature, forming a tight positive feedback system with the subtropical high.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Qiwei Sun, Yan Du, Shang-Ping Xie, Yuhong Zhang, Minyang Wang, Yu Kosaka
Summary: The POGA experiment successfully simulated the observed variability of sea surface salinity (SSS) in the eastern tropical Pacific. The long-term trend in SSS shows salty regions becoming saltier and fresh regions becoming fresher, modulated by the interdecadal Pacific oscillation (IPO). Decadal variability in the tropical Pacific has led to regional discrepancies in the estimation of radiative-forced trends, highlighting the importance of understanding internal variability in SSS trends.
JOURNAL OF CLIMATE
(2021)
Editorial Material
Environmental Sciences
Masato Mori, Yu Kosaka, Masahiro Watanabe, Bunmei Taguchi, Hisashi Nakamura, Masahide Kimoto
NATURE CLIMATE CHANGE
(2021)
Correction
Environmental Sciences
Masato Mori, Yu Kosaka, Masahiro Watanabe, Bunmei Taguchi, Hisashi Nakamura, Masahide Kimoto
Summary: A correction to this paper has been published.
NATURE CLIMATE CHANGE
(2021)
Article
Geosciences, Multidisciplinary
Kaiming Hu, Gang Huang, Ping Huang, Yu Kosaka, Shang-Ping Xie
Summary: The analysis of global climate model projections shows that greenhouse gas-induced warming intensifies atmospheric variability associated with the El Nino/Southern Oscillation (ENSO). This intensification is primarily due to the Clausius-Clapeyron relationship, whereby saturation vapor pressure increases nearly exponentially with increasing temperature. The findings provide a novel theoretical constraint for ENSO changes and reduce uncertainty in the ENSO response to greenhouse warming.
Article
Multidisciplinary Sciences
Yuhei Takaya, Yu Kosaka, Masahiro Watanabe, Shuhei Maeda
Summary: The interannual variability of the Asian summer monsoon has significant impacts on Asian society. Advances in climate modelling have enabled useful predictions of the seasonal Asian summer monsoon up to approximately half a year ahead, but long-range predictions remain challenging. Using a large ensemble hindcast experiment, researchers demonstrate that a state-of-the-art climate model can predict the Asian summer monsoon and associated tropical cyclone activity more than one year ahead by successfully simulating El Nino-Southern Oscillation evolution and realistically representing subsequent atmosphere-ocean responses in the Indian Ocean-western North Pacific.
NATURE COMMUNICATIONS
(2021)
Article
Meteorology & Atmospheric Sciences
Shion Sekizawa, Hisashi Nakamura, Yu Kosaka
Summary: Anomalous convective activity in the tropics influenced by sea surface temperature variability has remote impacts on extratropical climate. The Australian summer monsoon system internal variability affects East Asia and western North Pacific winter climate.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Takeshi Horinouchi, Yu Kosaka, Hiroshi Nakamigawa, Hisashi Nakamura, Norihisa Fujikawa, Yukari N. Takayabu
Summary: In early July 2020, a prolonged heavy rainfall event occurred in Kyushu, Japan, which was influenced by the Silk-Road teleconnection. The persistence of moisture flux and the presence of an upper-level trough played significant roles in this event.