Two dimensional model study of atmospheric transport using carbon-14 and strontium-90 as inert tracers

Conference · Sat Feb 01 04:00:00 EST 1992

OSTI ID:6436330

Kinnison, D E; Wuebbles, D J ^[1]; Johnston, H S ^[2]

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1. Lawrence Livermore National Lab., CA (United States)
2. Lawrence Berkeley Lab., CA (United States)

This study tests the transport processes in the LLNL two-dimensional chemical-radiative-transport model using recently reanalyzed carbon-14 and strontium-90 data. These radioactive tracers were produced bythe atmospheric nuclear bomb tests of 1952--58 and 1961--62, and they were measured at a few latitudes up to 35 kilometers over the period 1955--1970. Selected horizontal and vertical eddy diffusion coefficients were varied in the model to test their sensitivity to short and long term transpose of carbon-14. A sharp transition of K[sub zz] and K[sub yy] through the tropopause, as opposed to a slow transition between the same limiting values, shows a distinct improvement in the calculated carbon-14 distributions, a distinct improvement in the calculated seasonal and latitudinal distribution of ozone columns (relative to TOMS observations), and a very large difference in the calculated ozone reduction by a possible fleet of High Speed Civil Transports. Calculated northern hemisphere carbon-14 is more sensitive to variation of K[sub yy] than are global ozone columns. Strontium-90 was used to test the LLNL tropopause height at four different latitudes. Starting with the 1960 background distribution of carbon-14, we calculate the input of carbon-14 as the sum of each nuclear test of the 1961--62 series, using two bomb-cloud rise models. With the Seitz bomb-rise formulation in the LLNL model, we find good agreement between calculated and observedcarbon-14 (with noticeable exceptions at the north polar tropopause and the short-term mid-latitude mid-stratosphere) between 1963 and 1970.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: DOE; NASA; USDOE, Washington, DC (United States); National Aeronautics and Space Administration, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48; AC03-76SF00098
• OSTI ID: 6436330
• Report Number(s): UCRL-JC-108847; CONF-9202172--1; ON: DE93012547
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540130* -- Environment
Atmospheric-- Radioactive Materials Monitoring & Transport-- (1990-)
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ALKALINE EARTH ISOTOPES
ATMOSPHERIC EXPLOSIONS
BACKGROUND RADIATION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 14
CARBON ISOTOPES
EARTH ATMOSPHERE
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL TRANSPORT
EVEN-EVEN NUCLEI
EXPLOSIONS
FALLOUT
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LAWRENCE BERKELEY LABORATORY
LAWRENCE LIVERMORE LABORATORY
LIGHT NUCLEI
MASS TRANSFER
MATHEMATICAL MODELS
NATIONAL ORGANIZATIONS
NUCLEAR EXPLOSIONS
NUCLEI
RADIATIONS
RADIOISOTOPES
RADIONUCLIDE MIGRATION
STRATOSPHERE
STRONTIUM 90
STRONTIUM ISOTOPES
TRACER TECHNIQUES
TROPOSPHERE
US AEC
US DOE
US ERDA
US ORGANIZATIONS
YEARS LIVING RADIOISOTOPES