Sun & Volcanoes Control Climate It is accepted that volcanic
eruptions can have a major impact on short term climate. A new
study in Nature Geoscience uses instrument records, proxy data
and climate modeling to show that multidecadal variability is a
dominant feature of North Atlantic sea-surface temperature
(SST), which, in turn, impacts regional climate. It turns out
that the timing of multidecadal SST fluctuations in the North
Atlantic over the past 600 years has, to a large degree, been
governed by changes in external solar and volcanic forcings.
Solar influence is not surprising but the fact that volcanoes
cause climate change lasting decades has some significant
implications for those trying to model climate over the next
century. When a volcano erupts it spews large quantities of ash,
water vapor, sulfur dioxide and even some carbon dioxide into
the atmosphere. Sulfur dioxide reacts with water to form
sulfuric acid droplets (aerosol particles), which are highly
reflective and reduce the amount of incom