Meeting Europe's renewable energy targets in harmony with - RSPB

THE TWIN IMPERATIVES – STABILISING CLIMATE AND PROTECTING BIODIVERSITY 9
Increasing levels of carbon dioxide in the
atmosphere are also expected to lead to a gradual
acidification of the ocean with likely dramatic
consequences for all marine organisms with
calcium-based shells.
Society can help biodiversity adapt (Box 1), but the
primary response must be deep cuts in greenhouse
gas emissions to limit warming and stabilise the
climate at the rate and level required to allow
ecosystems to adapt naturally to climate change
(UNFCCC, Convention on Climate Change
Article 2). To have a greater than 50%
chance of keeping global temperature increases
from exceeding 2°C, the concentration of
greenhouse gases in the atmosphere will need to
be stabilised at well below twice pre-industrial
levels (Meinshausen, 2005; Baer and Mastrandrea,
2006). For this to be achievable, global
emissions will need to peak within the next
10–15 years and then be reduced by at least
50% by mid-century.
BOX 1
Can biodiversity adapt to climate change?
There is considerable concern that many species and
natural ecosystems will not be able to adapt fast enough
to keep up with the rapid rate of future climate change. As
the climate warms, species may adapt “autonomously”
through behavioural or evolutionary changes, or may
benefit from human intervention. The chances of success
vary between species and ecosystems, and will depend
on the extent of warming. Cutting greenhouse gas
emissions to limit future warming is paramount, but
planned adaptation is also essential because of global
warming that is already “in the pipeline” due to past
emissions. Fortunately, many key current conservation
actions are also those most required to address the
impacts of climate change. Actions particularly important
for climate change adaptation fall into four broad
categories:
Increasing the population of threatened species. This
increases “resilience”, by reducing the risks of local
extinction, and provides colonists for new sites. Actions
include enlarging and improving management of important
sites and special habitats. Large population sizes in
diverse habitats also maximise genetic diversity, assisting
evolutionary adaption to climate change. It must also be
remembered that climate change effects are synergistic
with other pressures, such as habitat loss and
fragmentation. Therefore, actions to reduce these
pressures, including through buffering wildlife sites,
will likely increase resilience to climate change.
Assisting species movement by increasing ecological
connectivity across landscapes. Better connected
landscapes will allow species to move naturally to track
the changing location of suitable climate. Key strategies
here include increasing the size of current wildlife sites
and creating new sites, as well as providing stepping
stones, corridors and management to make the
intervening landscape less hostile to specialist species.
This strategy is sometimes known as a “landscape scale”
approach to conservation.
Assisting relocation. For species with poor powers of
dispersal, and those in poorly connected landscapes,
help may be required to enable movement. In practice,
time and cost (as well as technical feasibility and
ecological risk) probably make this a viable option for
relatively few species. Captive breeding and conservation
of genetic material in seed and DNA banks are further
options for consideration.
Developing landscape heterogeneity. Creating climatic
refuges, below the mean temperature of their
surroundings, improves the chance that species can
stay in current locations. This enables local movements,
rather than requiring longer-distance dispersal, and can
enhance ecological resilience and accommodation of
species on the move.