Hideyuki Honda

TL;DR: In this article, the vertical profiles of carbon and oxygen stable isotopic ratios of the lower stratospheric CO 2 were measured using a balloon-borne cryogenic sampling system, and the relationship between δ 13 C and CO 2 mixing ratio (−0.07%o ppmv -1 ) was found to be similar to that for the seasonal variation in the troposphere rather than that for a secular variation so far observed in the tropical variation, in accordance with anthropogenic input of the isotopically light fuel CO 2 into the atmosphere.

TL;DR: The vertical distribution of isotopomers of N2O (14N15N16O, 15N14N 16O, and 14N 14N18N18O) in the lower and middle stratosphere was observed over Japan (39°N, 142°E) in 1999 using a balloon-borne cryogenic sampler and ground-based mass spectrometry as discussed by the authors.

TL;DR: In the higher-altitude region, fractionation of the isotopomers is mainly determined by photolysis, but is also affected by physical processes, such as subsidence of air masses in the winter polar vortex induces the intrusion of an upper stratospheric air mass depleted in N2O, and decay of the vortex in the local spring leads to rapid horizontal advection of midlatitude air masses as discussed by the authors.

TL;DR: In this article, high-precision measurements of not only the isotopic ratios of N2, O2 and Ar but also the mole fraction of Ar were used to show that gravity separation occurs even in the stratosphere below the turbopause; their observed vertical profiles are in good agreement with those expected theoretically from molecular mass differences.

TL;DR: In this paper, stable isotopic ratios of carbon (delta-C-13) and oxygen (Delta-O-18) of carbon dioxide in the stratosphere (18-35 km altitudes) over Japan since 1985 are presented.