Lisø PhD Dissertation Manuscript - NTNU

Figure 2 Empirically downscaled scenario showing increase
in winter precipitation (winter ¼ December^February). Values
are the di¡erence between the 2020^49 and 1961^90 periods
and are given as changes per decade in percentage of 1961^90.
The increase is larger than 1.5% per decade all over the country,
and the largest increase is 3.4% per decade
over the next 50 years, making the climate more similar
to conditions presently experienced in the middle of the
country. In the south of Norway the expected increase
in winter temperature is smaller, but this part of the
country is still expected to experience a warmer winter
climate in future, more similar to the current winter
climate in Denmark and southern areas of Sweden.
Several sources of uncertainties exist related to both
scenarios for global climate change, and to the effects
of global warming on regional-level climate. Climate
models differ in their indications of changes in the
North Atlantic Ocean current (Gulf Stream) and in
the extent of sea-ice cover in the Arctic. Changes in
ocean currents and sea-ice will directly influence on the
climatic conditions in Norway. The regional scenarios
should not be considered as forecasts in an absolute
sense. They offer insights into likely range and nature
of future weather scenarios.
Impacts of climate change
Many sectors of Norwegian society may be affected by
climate change. Impacts may be felt by economic
sectors directly or indirectly dependent on climatic factors
as well as environmental and social sectors. In the
energy and hydropower sector, increased precipitation
and runoff may enable increased power production. At
Norway’s built environment
the same time, however, increased temperatures are
likely to reduce household space heating and energy
demand (Sælthun, 1998). Present RegClim scenarios
indicate that the growing season may increase by 20–
30 days in large parts of the country up to 2050
(Skaugen and Tveito, 2002). A longer growing season
and an expansion of area suitable for crop cultivation
creates potential for increased yields, if optimal adaptations
of the crop calendar and switching to suitable
crop types are possible in the context of structural
changes in Norway’s agricultural sector (O’Brien et al.,
2002). The forestry sector may also see a lengthened
growing season and an expansion of land available for
forest production (Ministry of the Environment, 1991;
Parry, 2000). On the other hand, warmer weather may
increase the incidence of pests and diseases, soil erosion,
poor snow cover and hoar frost, posing threats to forest
and agricultural yields as well as to natural ecosystems
(Sygna and O’Brien, 2001). The fisheries sector is sensitive
to climatic changes in terms of fish stocks, introduction
of fish species from the south, and the frequency of
diseases (Loeng, 1995). Many communities in Norway
depend on the fishery sector. Overfishing has been an
important determining factor of fish stocks in the past
and the interaction between stock management and
climate change may be critical for the performance of
this sector in future.
Few studies have examined the links between climate
change and health in Norway, but studies in other parts
of Europe suggest that health is sensitive to climatic
events and changes. Health impacts occur via a variety
of mechanisms, the direct impacts including heat- and
cold-related illness and death related to thermal extremes
and deaths, as well as injuries and psychological
disorders related to other extreme weather events. In
addition, indirect effects may occur, for example, as a
result of disturbances in ecological systems and changes
in geographic ranges and incidence of vector-borne
diseases; in terms of respiratory disorders as a result of
increased levels of air pollution, including pollen and
spores; or in terms of mental health and nutritional
impairment, infectious diseases and civil strife as a result
of the effects of climatic changes on the economy, infrastructure
and resource supply (Palutikof et al., 1997;
Parry, 2000). This is a useful area of further research.
The maintenance of infrastructure and buildings is likely
to become more costly with an increase in precipitation
and wind and other meteorologically triggered events,
such as hurricanes, floods, avalanches and landslides.
Potential impacts and sensitivity of buildings and
building enclosures are examined in more detail below.
Climate vulnerability in Norway
De¢nitions of vulnerability
Vulnerability is generally perceived to have both a physical
and a social component. Chambers (1989 p.1)
defines vulnerability as:
203