RD&D-Programme 2004 - SKB

Shoreline displacement in Scandinavia after the last ice age is described in /20-81/ and a
forecast is given for the next 5,000 years. Shoreline displacement during several glaciations
was studied for SR 97 /20-82/. Shoreline displacement can be influenced by global warming,
which is expected to cause rising sea levels. The sea level may rise approximately 0.4 metre
over the next 100 years /20-83/. This means that shoreline displacement will cease for a period
of time, which has also been measured /20-84/. In the longer term, a future glaciation will
once again bind water in glaciers, resulting in a lowering of the sea level by around 100 metres
/20-82, 20-85, 20-86/. At the same time, the earth’s crust will be depressed under the ice load
by up to 800 metres in the central parts of the glaciated area and about 200–500 metres on the
sites being investigated by SKB /20-87/. This influences discharge areas on the coast, and the
environment around the deep repository. It also influences the salinity of the Baltic Sea and the
composition of the biosphere.
Conclusions in RD&D 2001 and its review
See section 20.2.
Newfound knowledge since RD&D 2001
The model that describes the salinity of the Baltic Sea /20-88/ has been further refined to predict
future salinities in the Baltic Sea depending on different climatic evolutions and shoreline
displacements /20-89/. The work has also resulted in international publications /20-90/.
The climate also influences groundwater recharge and water turnover in lakes and watercourses,
which can be important factors for flows at repository level, but also for which biosphere can be
expected. The greatest uncertainties concern the variations in precipitation and runoff. A project
was therefore initiated that studies and dates the occurrence of horizons in peat bogs that have a
deviant degree of humification which is considered to be due to dry periods /20-91 to 20-93/.
Further information on land uplift in Uppland has been obtained from compilations of field
studies /20-46, 20-94/, see sections 20.7 and 20.8.
Long-term climatic variations are also dealt with in Chapter 21.
Programme
Above all, climate change in Scandinavia during an interglacial stage will be studied.
Fundamental questions are how precipitation and runoff change. In addition, more information
is required on processes and formation rates in connection with permafrost and how this affects
the surface ecosystems. Parts of this knowledge are being produced in several national and
international projects, for example regarding short-term climate changes in Sweclim and longterm
ones in Bioclim. SKB is also planning projects for the next 1,000 years and an interglacial
stage, see section 21.3.
The climate questions are closely linked to the geosphere and geochemistry programmes as
well as scenario development. The site investigations will also produce data, especially when
it comes to the land uplift process, but also when it comes to the local climate. The main issues
that will be studied in upcoming research programmes are:
• Climate change in Scandinavia during interglacials in the form of a compilation of
information from completed studies.
• Knowledge compilation regarding permafrost and the importance of the tundra for
radionuclide transport in the biosphere.
• Follow the global warming discussion.
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