Use of excess /sup 14/C data to calibrate models of stratospheric ozone depletion by supersonic transports

Journal Article · Tue Jan 20 04:00:00 EST 1976 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JC081i003p00368· OSTI ID:7350861

Johnston, H S ^[1]; Kattenhorn, D; Whitten, G

---

1. Univ. of California, Berkeley

During 1974 at least 7 one-dimensional models of vertical eddy transport and photochemistry had been used to predict the reduction of ozone by nitrogen oxides from supersonic transports. Chang (1974) has shown that these predictions are sensitive to the assumed values for the vertical eddy diffusion coefficient K/sub z/. In this article an effort is made to calibrate the one-dimensional K/sub z/ functions against quantitative data for the dissipation of excess carbon 14 from the stratosphere during the period 1963-1970. The data for excess carbon 14, following nuclear bomb test series of 1961-1962, were published in 1971 and 1972, and these data were not used to derive the various K/sub z/ functions. Tables of data are presented in a form that may be useful to others in calibrating two- and three-dimensional models of stratospheric motion. In checking the one-dimensional models the direct observations by balloons at 30/sup 0/N are primarily used. Also, these data are interpreted as a special hemispherical average (averaging along lines parallel to a standard sloping tropopause). The carbon 14 data and strontium 90 data differ in many important respects, and it is judged that the carbon 14 data give the better estimate of air motion in the stratosphere. The seven K/sub z/ models give predictions that strongly differ from one model to another. The models that give a fairly realistic prediction of carbon 14 distribution and persistence are those with minimum K/sub z/ between 15 and 20 km and with increasing K/sub z/ from 20 to 50 km. Models with these features, as recalculated by Chang (1974), agree with each other as to ozone reduction by artificial nitrogen oxides from supersonic transports (SST's). These models are used to predict the ozone reduction by SST's according to Grobecker's (1974) upper bound projection out to the year 2025. Very large reductions of global ozone are indicated, more than a factor of 2.

• OSTI ID: 7350861
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 81:3; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR TRANSPORT
ALKALINE EARTH ISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CALIBRATION
CARBON 14
CARBON ISOTOPES
CHALCOGENIDES
CHEMICAL REACTIONS
EARTH ATMOSPHERE
ENVIRONMENTAL EFFECTS
EQUATIONS
EVEN-EVEN NUCLEI
FORECASTING
INTERMEDIATE MASS NUCLEI
ISOTOPES
LIGHT NUCLEI
MATHEMATICAL MODELS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NUCLEI
OXIDES
OXYGEN COMPOUNDS
OZONE
RADIOISOTOPES
REDUCTION
STRATOSPHERE
STRONTIUM 90
STRONTIUM ISOTOPES
SUPERSONIC TRANSPORT
TRANSPORT
YEARS LIVING RADIOISOTOPES