Robock and Liu, 1994
Robock, Alan and Yuhe Liu, 1994: The volcanic signal in Goddard
Institute for Space Studies three-dimensional model simulations.
J. Climate, 7, 44-55.
We have analyzed the transient calculations of the Goddard
Institute for Space Studies general circulation model for the
climatic signal of volcanic eruptions. By compositing the output for
2 different volcanoes for Scenario A and 5 different volcanoes for
Scenario B, we suppress the natural variability and extract the
Significant global mean surface air temperature cooling and
precipitation reduction are found for several years following the
eruptions, with larger changes in the Northern Hemisphere (NH)
than in the Southern Hemisphere. The global-average temperature
response lasts for more than four years, but the precipitation
response disappears after three years. The largest cooling in the
model occurs in the NH summer of the year after spring eruptions.
Significant zonal-average temperature reductions begin in the
tropics immediately after the eruptions and extend to 45°S - 45°N
in the year after the eruptions. In the second year, cooling is still
seen from 30°S to 30°N. Because of the low variability in this
model as compared to the real world, these signals may appear
more significant here than they would by attempting to isolate them
using real data. The results suggest that volcanoes can enhance the
drought in the Sahel. No evidence was found that stratospheric
aerosols from the low-latitude volcanic eruptions can trigger ENSO
events in this model.
Prepared by Alan Robock (firstname.lastname@example.org ) -
Last updated on April 2, 1999