Measurements of stratospheric carbon dioxide and water vapor at northern midlatitudes: Implications for troposphere-to-stratosphere transport

Journal Article · Sun Oct 15 04:00:00 EDT 1995 · Geophysical Research Letters

DOI:https://doi.org/10.1029/95GL02337· OSTI ID:254550

Boering, K A; Wofsy, S C; Daube, Jr, B C ^[1]

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1. and others

Simultaneous in situ measurements of CO{sub 2} and water vapor in the lower stratosphere were obtained in November 1992 and May 1993 up to 21 km at midlatitudes. Seasonal changes in both species were observed up to pressure-altitudes of 19 km ({approximately}440K), a result of vertical propagation of seasonal oscillations in CO{sub 2} and H{sub 2}O mixing ratios for air entering the stratosphere in the tropics followed by horizontal transport to midlatitudes. The inferred phase difference between their seasonal cycles at the tropical tropopause (2 months) remained coherent at midlatitudes, although the amplitudes were reduced, implying a mean transport time of 4-6 months from the tropical tropopause ({approximately} 16 km) to {approximately}18.5-19 km at midlatitudes in both November and May. The measurements indicate that air enters the stratosphere throughout the year and suggest that vertical propagation of the seasonal minimum in water vapor, rather than deep convective overshoot, is both sufficient and necessary to explain the minimum in water ({open_quotes}hygropause{close_quotes}) observed several kilometers above the tropopause. 32 refs., 3 figs.

• OSTI ID: 254550
• Journal Information: Geophysical Research Letters, Journal Name: Geophysical Research Letters Journal Issue: 20 Vol. 22; ISSN GPRLAJ; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ATMOSPHERIC CIRCULATION
CARBON DIOXIDE
MIXING
STRATOSPHERE
TRACER TECHNIQUES
TROPOSPHERE
WATER VAPOR