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It is difficult to make precise calculations of the future level of greenhouse gases in the atmosphere—
and consequently the temperature rises and climate change of the future. This depends on a whole
host of factors such as technological and economic development and, in particular, whether success is
achieved in efforts to reduce greenhouse gas emissions.
THE CLIMATE OF THE FUTURE—SELECTION OF PROJECTIONS
The climate adaptation plan adopts a development scenario in line with the SRES A2 scenario of the
UN’s Intergovernmental Panel on Climate Change (IPCC). This development scenario is a projection of
how the climate will change in the future. This scenario assumes that the global mean temperature
will rise by around 3 degrees over the course of the 21st century. This projection includes the reporting
that has taken place since COP15 on limiting emissions. In addition, the latest calculations and registra-
tions of ice and snow melting show that substantially greater melting is taking place than has been as-
sumed in earlier calculations. This means that the consequences of melting are correspondingly great-
er than previous calculations have assumed.
The Ministry of Climate and Energy has recommended that municipalities apply the IPCC’s A1B scenar-
io for planning in relation to climate change over the next 50 years. However, this recommendation
came after the work on drawing up this plan had been carried out, where conditions for the calcula-
tion of future climate consequences had been chosen and calculation work had started.
The City of Copenhagen has used the IPCC’s A2 scenario as a basis for assessing future climate impacts.
It makes virtually no difference in relation to a timeframe of 50 years, as the two scenarios are almost
identical within this period. It is not until timeframe of 100 years that there is a significant difference
between the two scenarios. But as there is great uncertainty over the future development of the cli-
mate, no purpose is served by deciding in favour of one or other scenario. One should instead look at
the direction in which development is moving, as the projections become better, and regularly up-
date the need for climate adaptation measures in accordance with the new knowledge we acquire on
the climate of the future. This plan therefore does not recommend investments being made now in
relation to the long-term projections but instead recommends taking account of the need for climate-
proofing in municipal planning so that urban development does make appropriate implementation of
climate adaptation measures impossible.
In terms of measures in 50 years, the choice between A2 and A1B thus does not make any difference in
relation to recommendations on action.
No one knows precisely how the world will develop technologically, in population terms, politically
etc., or precisely how this will affect the climate, and whether this will be overlain by natural disasters
etc. The figures and projections in this plan are thus chosen on the basis of best available knowledge
on how the climate may perhaps develop and the consequences that will follow from this. The assess-
ments have been essentially based on the IPCC’s reports, the latest reports from the Danish Meteoro-
logical Institute (DMI) in connection with climate strategy for the Capital Region, the publications of
the Water Pollution Committee of the Society of Danish Engineers and the high-water statistics of the
Danish Coastal Authority etc.
The projections contained in the plan are not considered to the final. But they can be used to illustrate
the consequences of the possible climate changes focused on in this plan. It is worth noting in this con-
nection that even if success is achieved in making substantial reductions in global emissions of green-
house gases, the quantity of greenhouse gases that has already been emitted will inevitably lead to
changes in the earth’s climate.
The predictions on the climate of the future will become steadily more precise as the climate models
are developed. This will provide a better basis for assessing the necessary measures for climate adapta-
tion. The next report from the UN’s Intergovernmental Panel on Climate Change is expected in 2013.