Abstract
A 100 km deep liquid water ocean probably underlies the icy exterior
of Jupiter's satellite Europa. The long-term persistence of a liquid
ocean beneath an ice shell presents a thermal conundrum: Is the temperature
of the ocean equal to the freezing point of water at the bottom of
the ice shell, or is it equal to the somewhat warmer temperature
at which water attains its maximum density? We argue that most of
the ocean is at the temperature of maximum density and that the bulk
of the vigorously convecting ocean is separated from the bottom of
the ice shell by a thin "stratosphere" of stably stratified water
which is at the freezing point, and therefore buoyant. If Europa's
subsurface water ocean is warm, it could explain the widespread geologic
evidence for apparent melt-through events observed on its surface
and may constrain the overall age of its surface. (C) 2003 Elsevier
Inc. All rights reserved.
Users
Please
log in to take part in the discussion (add own reviews or comments).