RD&D-Programme 2004 - SKB

The salinity of the sea, inland sea or lake corresponding to today’s Baltic Sea in various
stages of a glaciation is affected by connections with the oceans. These connections are in
turn dependent on the thickness and extent of the continental ice sheet and the position of the
shoreline. Studies within the biosphere programme show that freshwater influx is at least as
important for the salinity, see section 20.8. Possible variations in salinity have been described
for various possible combinations of freshwater influx and shoreline.
The state of knowledge concerning conditions and processes in the temperate/boreal climate
domain and their importance for repository safety and conditions in the biosphere is good.
Conclusions in RD&D 2001 and its review
Both SKI and SSI are of the opinion that in coastal regions, the future position of the shoreline
and its impact on groundwater conditions and the biosphere is an important issue.
Newfound knowledge since RD&D 2001
As already mentioned, empirical studies of land uplift since the most recent deglaciation have
been concluded /21-3/. More detailed studies have been conducted of land uplift in Uppland,
see section 20.8. This means that our current knowledge of historical conditions and our ability
to predict the isostatic progression over the next 1,000 years are very good. Together with the
aforementioned results, the descriptions of sea level changes arrived at by the IPCC /21-6/
provide information on shoreline displacement for the next 1,000 years that is judged to be
sufficient for the needs of the safety assessment.
Human impact on the climate is the process that has been studied more than any other in order
to predict the future evolution of the climate. SKB has not conducted any studies of its own
within the area. Published results, particularly within the projects Sweclim /21-5/ and Bioclim
/21-1, 21-2, 21-4/ and through the IPCC, are judged to be sufficient for SKB’s purposes.
Programme
A compilation and synthesis of climate variations, mainly in the Holocene but also in earlier
periods since the most recent deglaciation, has long been planned. The study is intended to shed
light on climate variations during interglacials as well as possible climatic conditions southeast
of an ice sheet that partially covers the country. The study will also provide data as a basis for
setting limits within which temperature and precipitation vary during the temperate/boreal
domain.
A project has been started for the purpose of describing and understanding the causes of the
climate variations we can see in Scandinavia during the past 2,000 years, and evaluating how
information from climate archives can be used together with climate models to describe the
climate. This project is expected to provide data as a basis for describing climate changes over
the next 1,000 years, even taking into account possible human impact on the climate.
The above-mentioned GIA project will provide information on the shoreline in various stages of
a glacial cycle. The results can also be used to simulate what would happen with the shoreline in
a greenhouse scenario where the cycle of ice ages is disrupted and today’s continental ice sheets
melt.
The current state of knowledge concerning conditions in the temperate/boreal domain is good.
Model simulations within Bioclim /21-2/ show that a very long period with a warm climate
similar to today’s could be a consequence of human impact on the climate. In view of this, the
consequences of a very long period with temperate/boreal conditions is planned to be studied
more closely, see also section 20.8.
300 RD&D-Programme 2004