Dimension of D&A

• Purely scientific• Stakeholder utility• Attribution – the

competitors• Falsification

• Purely scientific• Statistical rigor (D) and plausibility (A).• D depends on assumptions about “internal

variability”• A depends on model-based concepts.• Thus, remaining doubts exist beyond the

specified.

Dimension of D&A

• Stakeholder utility• Evidence that anthropogenic warming is

related to human drivers – serving as an arguments to implement broad global mitigation measures.

• Evidence that recent change is part of an ongoing (predictable) pattern, or not. Serving as information to guide regional and local adaptation measures.

Dimension of D&A

This is what we need to know more about

• Attribution – the competitors• Climate drivers – relatively easy; not too many

drivers, such as urbanization, aerosol, land-use.• Impact drivers – hardly dealt

with. Many drivers: eutrophication, pollution, overuse, regulation, globalization.

• Example: Baltic Sea ecosystems

Dimension of D&A

“Mini-IPCC” assessment on knowledge about climate change in the

Baltic Sea Basin

• Falsification• Which observations in the coming 5/10 (?) years

would lead to reject present attributions?• Suggestion: Formulate and freeze NOW

falsifiable hypotheses, and test in 5/10 (?) years time – using the independent data of the additional years.

• Suggestion: Have assessment done by scientists independent of those, who formulated the hypotheses.

Dimension of D&A