Date

Dec 18, 1984

Description

During a visit to Washington, Joseph Knox of LLNL had acquired a copy of the “prepared release,” the summary and conclusions, for the NRC/National Academy of Sciences study on nuclear winter. On the text, he made a number of marginal comments, which he acknowledged to the readers of his cover memo, might be read as conveying the “belief [that] the report could have been better.” But he was far more positive: “I am relieved that the NAS report is as good as it is.” He remained concerned that some of the uncertainties about smoke and soot emissions from fires “were deemphasized a bit.”

The NRC report issued a few weeks later avoided definitive language or quantitative conclusions, but the committee found that a nuclear exchange involving 6500 megatons (half of the world’s stockpile) could have “long-term climatic effects with severe implications for the biosphere.” The nuclear exchange would “insert significant amounts of smoke, fine dust, and undesirable chemical species into the atmosphere,” and the “depositions could result in dramatic perturbations of the atmosphere lasting over a period of at least a few weeks.” There was a “clear possibility that great portions of the land areas of the northern temperate zone (and a larger segment of the planet) could be severely affected,” with possible effects including “major temperature reductions (particularly for an exchange that occurs in the summer) lasting for weeks, with subnormal temperatures persisting for months.” Uncertainties notwithstanding, the report thus suggested even greater danger from nuclear war.

Source

DOE FOIA Release

Document published in following posting(s):

Nuclear Winter: U.S. Government Thinking During the 1980s

Jun 2, 2022

Investigating the Climate Impacts of Nuclear War

Oct 30, 2024