|
Working Group on Paleoclimate:
Activities 2007 - 2009
Reconstructing past climate provides a
useful context for the discussion on the
twentieth century global warming and
future climate changes. In their recent
paper published in the Geophysical
Research Letters, Shaopeng Huang and
Henry Pollack of the University of
Michigan and Po-Yu Shen of the
University of Western Ontario present a
suite of 20,000 year reconstructions
that integrate three types of geothermal
information: a global database of
terrestrial heat flux measurements,
another database of temperature versus
depth observations, and instrumental
record of temperature. These
reconstructions show the warming from
the last glacial maximum, the occurrence
of a mid-Holocene warm episode, a
Medieval Warm Period (MWP), a Little Ice
Age (LIA), and the rapid warming of the
20th century. The reconstructions show
the temperatures of the mid-Holocene
warm episode some 1–2 K above the
reference level, the maximum of the MWP
at or slightly below the reference level,
the minimum of the LIA about 1 K below
the reference level, and end-of-20th
century temperatures about 0.5 K above
the reference level. Huang was invited
to participate in the Workshop on
Bayesian Hierarchical Models for
High-Resolution Climate Reconstructions
organized by Casper Amman at the
National Center for Atmospheric Research
in Boulder, CO, USA. Two other IHFC
members invited to this workshop were
David Chapman of the University of Utah
and Robert Harris of Oregon State
University.
As
another focus of the working group
"Paleoclimate" session CL35 "Subsurface
temperature signals of climate change,
processes involved, and importance to
climate modeling" was organized as part
of the section "Climate: Past, Present,
Future" of the General Assembly of the
European Geosciences Union in Vienna in
April 2008 by V. Rath, J. Gonzales-Rouco
and IHFC member J. Safanda. Altogether
30 contributions (11 oral contributions
including 4 solicited ones and 19
posters) addressed different aspects of
the surface temperature history
reconstruction from the present
subsurface temperature profiles. The
conveners of the session have agreed on
organization of such a session every
second year, which means that the next
meeting of this kind should be convened
in the spring of 2010.
|
