Abstract
Variability of subtropical cell (STC) overturning in the upper Pacific
Ocean is examined in a coupled climate model in light of large observed
changes in STC transport. In a 1000-yr control run, modeled STC variations
are smaller than observed, but correlate in a similar way with low-frequency
ENSO-like variability. In model runs that include anthropogenically
forced climate change, STC pycnocline transports decrease progressively
under the influence of global warming, attaining reductions of 8%
by 2000 and 46% by 2100. Although the former reduction is insufficient
to fully account for the apparent observed decline in STC transport
over recent decades, it does suggest that global warming may have
contributed to the observed changes. Analysis of coupled model results
shows that STC transports play a significant role in modulating tropical
Pacific Ocean heat content, and that such changes are dominated by
anomalous currents advecting mean temperature, rather than by advection
of temperature anomalies by mean currents.
Users
Please
log in to take part in the discussion (add own reviews or comments).