Engineering topics

Crutzen, P. J.

Publications and source records attributed to Crutzen, P. J..

22 records · Page 2

NASA NTRS1978

The origin of ozone in the troposphere

Examination of the distribution of tropospheric ozone indicates that surface destruction in the Northern Hemisphere (NH) should be about three times larger than in the Southern Hemisphere (SH). If, according to the traditional understanding of ozone, this species were a passive tracer in the troposphere, a threefold larger flux out of the stratosphere should exist in the NH than in the SH. However, meteorological analyses fail to support such pronounced hemispheric differences in stratosphere-troposphere exchange. Alternatively, therefore, it is hypothesized that photochemical synthesis of ozone in the troposphere may be particularly important in the NH because of asymmetries in the sources and distribution of carbon monoxide, hydrocarbons and nitric oxide.

Fishman, J.↗

NASA NTRS1978

Estimates on the production of CO and H2 from the oxidation of hydrocarbon emissions from vegetation

Extrapolating from extensive field measurements on foliar emissions in the U.S. approximate global inputs of isoprene and terpenes of 3.5 times 10 to the 14th power and 4.8 times 10 to the 14th power g(C)/yr, respectively, are obtained. The oxidation of these hydrocarbons could contribute in an important way to the atmospheric sources of CO (4.2-13.3 times 10 to the 14th power g/yr) and H2 (10-35 times 10 to the 12th power g/yr), and to organic species soluble in rainwater

Zimmerman, P. R.↗

NASA NTRS1977

Solar proton event - Influence on stratospheric ozone

Large-scale reductions in the ozone content of the middle and upper stratosphere over the polar cap regions were associated with the major solar proton event of 4 August 1972. This reduction, which was determined from measurements with the backscattered ultraviolet experiment on the Nimbus 4 satellite, is interpreted as being due to the catalytic destruction of ozone by odd-nitrogen compounds (NOx) produced by the event.

Heath, D. F.↗

NASA NTRS1976

Influence of a solar proton event on stratospheric ozone

Ozone depletion in the stratosphere associated with the solar proton event of August 4, 1972, was observed with the backscattered ultraviolet experiment on the Nimbus 4 satellite. An abrupt ozone decrease in the 75-80 deg N zone of about 0.002 atm-cm above 4 mb was observed to persist throughout the month of August. A decrease was noted in the 55-65 deg N zone on days 219 and 220, but recovery occurred on day 221. Thereafter, a more gradual decrease was observed. The equatorial zone also showed gradual decrease after day 218, but these were not uniquely distinguished from seasonal variations. The observed change in total ozone following the event was -0.003 atm-cm for the 75-80 deg N zone, corresponding to a 1.3 percent reduction in the 0.305 atm-cm zonal average, but within the 0.019 atm-cm standard deviation. Above the 10 mb surface in the 75-80 deg N zone however, a decrease of 0.004 atm-cm may be compared with a standard deviation of 0.001 atm-cm.

Heath, D. F.↗