Futures Scientific challenges Rapid climate change The blue Arctic Political/social The international dimension Norway’s key contributions Long-term vs short-term research

Rapid climate change We still don’t know What caused it in the past Why the glacial state is more prone to large changes than the interglacial Arctic fresh water budget Some promising lines of enquiry have emerged Mixing/convection in the high-latitude seas relation to atmospheric forcing, NAO etc. Large-scale atmospheric forcing interbasin water vapour transport. Global thermohaline structure Relation of 1.5 ka cycle to solar forcing

Rapid climate change There are signs of change in the THC… Warming and Freshening of the Nordic Seas and Northernmost Atlantic Change in overflows Change in convection patterns

The blue Arctic Within our children’s lifetime: The Arctic ocean may be largely ice-free in summer. The extent of permanent snow cover on land in the high Arctic will have greatly diminshed.

The blue Arctic The lower albedo will alter the energy balance of the Arctic and of the planet as a whole. The circulation patterns of the Arctic and surrounding seas will probably change. The “Super-interglacial” climate, with a single polar cap will be unlike any climate in the last several million years. How will this change occur? What will the impacts be on this part of the world?

Political and social challenges Understanding Arctic climate change is part of the larger challenge of understanding the Earth system. The system has a complexity on a par with a living organism (c.f J. E. Lovelock) Understanding causes of climate change may be as difficult as understanding the causes of cancer (cf W. S. Broecker). Each important sub-system must be understood. Emergent properties of the whole are more than the sum of the parts.

Explaining to politicians and public Emphasise the long-term nature of the problem, but... Show that advances are being made in the short term. Identify key contributions from Norway. Ensure the program is embedded in an international effort.

Norway’s key contributions? Observations of, and experience in, the Nordic Seas and Arctic. Interpretation of climatology Paleo-studies. Innovative and high-resolution modelling.