Takakiyo Nakazawa

O 2 :CO 2 exchange ratio and isotopic composition of atmospheric O 2 measured using soil chambers, and their application to evaluating enhanced rock weathering and the Dole–Morita effect

Shigeyuki Ishidoya, Takahisa Maeda, Hidehiko Kikuno, Jumpei Fukumasu et autres

Abstract. Soil chamber measurements of δ(O2/N2), CO2 amount fractions, and the δ(18O) of O2 in air (δatm(18O)) were conducted at a forest site in Takayama (TKY), Japan, and at agricultural fields in Tsukuba (TKB) and Miyakojima (MYK), Japan. The latter fields included …

jp (code pays fourni par la source)

Stratospheric δ 13 CO 2 observed over Japan and its governing processes

Satoshi Sugawara, Shinji Morimoto, Shigeyuki Ishidoya, Taku Umezawa et autres

Due to very few reports of δ 13 CO 2 (the stable carbon isotopic ratio of CO 2 ) observations in the stratosphere, its variations are not well understood. In order to elucidate stratospheric δ 13 CO 2 variations and their governing …

jp (code pays fourni par la source)

Kinetic fractionation of noble gases in the stratosphere over Japan

Satoshi Sugawara, Ikumi Oyabu, Kenji Kawamura, Shigeyuki Ishidoya et autres

Abstract. Gravitational separation of gas species in the stratosphere is caused mainly by molecular diffusion and is a powerful tool to diagnose stratospheric transport processes. Previous studies have shown that isotopic and elemental ratios of major atmospheric components decrease with increasing altitude …

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Supplementary material to "Kinetic fractionation of noble gases in the stratosphere over Japan"

Satoshi Sugawara, Ikumi Oyabu, Kenji Kawamura, Shigeyuki Ishidoya et autres

Supplementary material to "Stratospheric δ 13 CO 2 observed over Japan and its governing processes and potential as an air age tracer"

Satoshi Sugawara, Shinji Morimoto, Shigeyuki Ishidoya, Taku Umezawa et autres

Stratospheric δ 13 CO 2 observed over Japan and its governing processes and potential as an air age tracer

Satoshi Sugawara, Shinji Morimoto, Shigeyuki Ishidoya, Taku Umezawa et autres

Abstract. Due to very few reports of δ13CO2 (the stable carbon isotopic ratio of CO2) observations in the stratosphere, its variations are not well understood. In order to elucidate stratospheric δ13CO2 variations and their governing mechanisms, and to investigate usefulness of δ13CO2 …

jp (code pays fourni par la source)

改良型クライオサンプラー性能実証試験（2024年度国内申請実験）

Satoshi Sugawara, Shinji MORIMOTO, Shuji AOKI, Hideyuki HONDA et autres

jp (code pays fourni par la source)

The Dome Fuji ice core DF2021 chronology (0–207 kyr BP)

Ikumi Oyabu, Kenji Kawamura, Christo Buizert, Frédéric Parrenin et autres

Precise ice-core chronologies are essential for identifying the timing and duration of polar climatic changes as well as their phasing with the changes in other parts of the globe. However, existing ice-core chronologies beyond the last 60 kyr show relatively large disagreements …

jp, us, fr, ca (code pays fourni par la source)

Towards reconstructing the Arctic atmospheric methane history over the 20th century: measurement and modelling results for the North Greenland Ice Core Project firn

Taku Umezawa, Satoshi Sugawara, Kenji Kawamura, Ikumi Oyabu et autres

Systematic measurements of atmospheric methane (CH 4 ) mole fractions at the northern high latitudes only began in the early 1980s. Although CH 4 measurements from Greenland ice cores consistently covered the period before ∼ 1900, no reliable observational record is available …

jp, gb (code pays fourni par la source)

Fractionation of O 2 ∕N 2 and Ar∕N 2 in the Antarctic ice sheet during bubble formation and bubble–clathrate hydrate transition from precise gas measurements of the Dome Fuji ice core

Ikumi Oyabu, Kenji Kawamura, Tsutomu Uchida, Shuji Fujita et autres

The variations of δO2/N2 and δAr/N2 in the Dome Fuji ice core were measured from 112 m (bubbly ice) to 2001 m (clathrate hydrate ice). Our method, combined with the low storage temperature of the samples (−50 ∘ C), successfully excludes post-coring …

jp, us (code pays fourni par la source)

Comment on acp-2021-736

Taku Umezawa, Satoshi Sugawara, Kenji Kawamura, Ikumi Oyabu et autres

Abstract. Systematic measurements of atmospheric methane (CH4) mole fractions at the northern high latitudes only began in the early 1980s. Although CH4 measurements from Greenland ice cores consistently covered the period before ∼ 1900, no reliable observational record is available for the …

jp, gb (code pays fourni par la source)

Towards reconstructing the Arctic atmospheric methane history over the 20th century: measurement and modeling results for the NGRIP firn

Taku Umezawa, Satoshi Sugawara, Kenji Kawamura, Ikumi Oyabu et autres

Abstract. Systematic measurements of atmospheric methane (CH4) mole fractions at the northern high latitudes only began in the early 1980s, and whilst CH4 measurements from Greenland ice cores covered the period before ~1900, no reliable observational record is available for the intermediate …

jp, gb (code pays fourni par la source)