In a 1990 paper entitled "Climate and Smoke: An Appraisal of Nuclear Winter", TTAPS gave a more detailed description of the short- and long-term atmospheric effects of a nuclear war using a three-dimensional model:
First one to three months:
10–25% of soot injected is immediately removed by precipitation, while the rest is transported over the globe in one to two weeks
SCOPE figures for July smoke injection:
22 °C drop in mid-latitudes
10 °C drop in humid climates
75% decrease in rainfall in mid-latitudes
Light level reduction of 0% in low latitudes to 90% in high smoke injection areas
SCOPE figures for winter smoke injection:
Temperature drops between 3 and 4 °C
Following one to three years:
25–40% of injected smoke is stabilised in atmosphere (NCAR). Smoke stabilised for approximately one year.
Land temperatures of several degrees below normal
Ocean surface temperature between 2 and 6 °C
Ozone depletion of 50% leading to 200% increase in UV radiation incident on surface.