Regional Impacts - Climate Resilient Agriculture for Ensuring Food Security - page 102

5.7.1 Adaptation and Vulnerability

which explicitly addresses climate scenarios,
projected changes in water supply and demand,
and adaptation options. A large amount of the overall vulnerability of

Arctic freshwater resources to climate change
relate to the abrupt changes associated with solid-
to-liquid water-phase changes that will occur in
many of the cryospheric hydrological systems.
Arctic freshwater ecosystems have historically
been able to adapt to large variations in climate,
but over protracted periods. The rapid rates of
change over the coming century, however, are
projected to exceed the ability of some biota to
adapt and to result in more negative than positive
impacts on freshwater ecosystems.
From a human-use perspective, potential adap-
tation measures are extremely diverse, ranging
from measures to facilitate use of water resources
(e.g., changes in ice-road construction practices,
increased open-water transportation, fl ow regula-
tion for hydroelectric production, harvesting
strategies, and methods of drinking-water access)
to adaptation strategies to deal with increased/
decreased freshwater hazards (e.g., protective
structures) to reduce fl ood risks or increase fl ows
for aquatic systems. Strong cultural and/or social
ties to traditional uses of water resources by some
northern people, however, could complicate the
adoption of some adaptation strategies.

5.7 Polar Regions (Arctic

and Antarctic)

• Northward movement of species in response
to higher temperatures and longer growing
season provides opportunities for expansion
of agricultural and pastoral activities but with
associated vulnerabilities related to invasive
species, loss of biodiversity, and the spread of
animal-transmitted diseases. An estimated
10-50 % of the tundra could be replaced by
scrubland and forests.
• Ecosystems will be affected by temperature
increase, decreased sea-ice cover, and shifts in
hydrological regimes, leading to detrimental
effects on many organisms, including migra-
tory birds, mammals, and higher predators.
• Food security of some subsistence systems
will be threatened by changes in ecosystems,
decreased transport and market access, and
lower-quality drinking water.
• Biodiversity changes and alterations in the
distribution and productivity of marine biota
will have mainly negative effects at the north-
ern ice edge but will benefi t the most impor-
tant Arctic and sub-Arctic commercial fi sh
stocks, such as cod and herring, south of the
ice edge.
Meng et al. ( 2013 ) assessed the literature for
the polar region (Arctic and Antarctica). With
medium confi dence, they concluded that the
benefi ts of a less severe climate were dependent
on local conditions. One of these benefi ts was
judged to be increased agricultural and forestry
opportunities.
Hennessy et al. ( 2007 ) reported on how
climate change had affected agriculture in Iceland.
Rising temperatures had made the widespread
sowing of barley possible, which had been unten-
able 20 years ago. Some of the warming was
due to a local (possibly temporary) effect via
ocean currents from the Caribbean, which had
also affected fi sh stocks.

5.8 Small Islands

• Agricultural land and thus food security will
be affected by sea-level rise, inundation, soil
salinization, seawater intrusion into freshwa-
ter lenses, and decline in freshwater supply.
• Agricultural production will be affected
overall by extreme events.
• Fisheries will be affected by increasing sea sur-
face temperatures, rising sea level, and damage
from tropical cyclones. Degradation of coral
reefs and bleaching will impact fi shing incomes.
• Forests affected by extreme events will be
slow to regenerate. Forest cover may increase
on some high-latitude islands.
• Habitability and thus sovereignty of some
states will be threatened due to reduction in
island size or complete inundation.