Geophysical Institute of the ASCR

the paleoclimate evolution of up to several past
centuries. In the last 10 – 15 years the
inversion technique to infer the climate history
from temperature-depth records became a
useful alternative method of general
paleoclimate reconstruction studies.
The inversion results from almost 100
boreholes from the Czech territory were
interpreted and the past climate scenario
proposed for the last millennium reflecting
also some regional characteristics (Čermák
and Bodri, 1999, Šafanda et al., 1997). As
a continuation of these studies three
experimental sites were selected to monitor
shallow subsurface temperature-time variations
to quantitatively assess the magnitude of the
present-day (global) warming. In 2004 two
research projects have been solved, both
addressing the air-soil temperature coupling
and the possibility to distinguish between the
natural and anthropogenic components of the
warming. The main objectives of the GAAV
grant A3012005 “Recent Climate Change and
Its Contingent Component Revealed by
Inversion of Present Temperature Data
Measured in Boreholes” (2000 – 2004) covered
year-long temperature monitoring in two of
these sites up to 40 m depth to complete the
inverted ground surface temperature histories
(GSTHs) by information on the regional trends
Fig. 4. Monitoring results from the Spořilov hole
demonstrating the gradually diminishing surface
“climate” signal with depth.
and to correlate the results with meteorological data. The GAČR grant „Climate Change and Global
Warming – Evidence From the Underground“ (2003 – 2005) completed the previous investigations by
a new observational site, located in one of the most environmentally polluted area of the Krušné Hory
Mts., where the maximum warming rate should be observed supposedly.
The important part of the paleoclimate investigations are the studies of the time succession of the
climate extremes and of the high-frequency climate variation. The knowledge of the existing climate
variability can help in the climate prognosis, e.g. in the estimate of the number of climate extremes
and their tendency to grow or fall. The climate models incorporating the increasing concentration of
the green-house gases suggested that the present climate warming might be connected with the
decreasing high frequency temperature variability. The monitoring temperature results from both
experimental boreholes were used to assess the variability at several selected frequencies, when the
absolute differences between the mean temperature anomalies at various intervals were taken as the
variability measure (Bodri and Čermák, 2003b).
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