Work Program
The work proposed in the present project is designed to fulfill
the social need for anticipation of both the qualitative and quantitative
aspects of the present climate change. This involves understanding
the natural causes of rapid variation (including abrupt changes), the
influence of anthropogenic activities and the most immediate effects
in the Iberian Peninsula.
Continental climate records will be primarily based on the analysis
of lacustrine sedimentary sequences. Lakes are dynamic depositional
settings that contain complete signals on the evolution of the surrounding
landscape and aquatic system as well as of the responses of biotic
and abiotic processes to climate variability. Much of this information
is stored in lacustrine sediments, for which a multi-proxy methodology
would be especially suited to resolve the different parameters that
control or influence sedimentary deposits, and to provide information
for decoding parameters such as temperature, precipitation, changes
in vegetation and seasonality. The use of such a methodology requires
a fully detailed and accurate chronology, which we will construct
from the results of 210Pb and 137Cs isotopic analyses, AMS radiocarbon
dating and U/Th analysis.
Additionally, the recent analyses of speleothems from different
caves in northern Iberian Peninsula will provide a complementary
archive of past climate variations in terms of precipitation and
temperature on land that will be contrasted with the results found
by studying lacustrine records.
The analytical methodologies that we will use to study lacustrine
samples will comprise a group of sedimentological, mineralogical,
geochemical and biological techniques capable of detecting changes
in lake level, chemical composition and limnological conditions,
such as streaming analysis of samples by X-ray fluorescence scanning, magnetic
properties, bulk and trace geochemical compound
analysis, geochemistry of stable isotopes palynology
and analysis of biological indicators, including diatoms, ostracods
and chironomids. Stable isotope analyses and U/Th dating will be
performed in selected speleotherms from the Iberian Peninsula.
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