(PIRCA), this report - Climate Adaptation Knowledge Exchange

Executive Summary
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• Rising ocean acidification and changing carbonate chemistry will have
negative consequences for the insular and pelagic marine ecosystems; although
potentially dramatic, the exact nature of the consequences is not yet clear.
• Distribution patterns of coastal and ocean fisheries will be altered, with
potential for increased catches in some areas and decreased catches in other
areas, but open-ocean fisheries being affected negatively overall in the long
term.
• Increasing temperatures, and in some areas reduced rainfall, will stress
native Pacific Island plant and animal populations and species, especially in
high-elevation ecosystems, with increased exposure to non-native biological
invasions and fire, and with extinctions a likely result.
• Threats to traditional lifestyles of indigenous communities in the region
(including destruction of coastal artifacts and structures, reduced availability
of traditional food sources and subsistence fisheries, and the loss of the land
base that supports Pacific Island cultures) will make it increasingly difficult for
Pacific Island cultures to sustain their connection with a defined place and their
unique set of customs, beliefs, and languages.
• Mounting threats to food and water security, infrastructure, and public health
and safety will lead increasingly to human migration from low islands to high
islands and continental sites.
This assessment also highlights the following:
• The high interannual and interdecadal variability of the climate in the Pacific
Islands region (e.g., ENSO, Pacific Decadal Oscillation) makes it difficult to
discern long-term trends from short-term data.
• Many Pacific Islands lack long-term, high-quality data on rainfall, streamflows,
waves, and ecosystems, and continued monitoring is needed.
• Global circulation models need to be downscaled to provide higher resolution
projections for Pacific Islands to account for the influence of local topography
on weather patterns and the potential impact of climate change on ecosystems.
• Sea level in the Western North Pacific has risen dramatically starting in the
1990s. This regional change appears to be largely wind-driven, is associated
with climate variability, and is not expected to persist over time.
• Some islands in the region have no human inhabitants and few human
impacts, offering a relatively pristine setting in which to assess the impacts of
climate change on natural settings.
• Integrated biological, geochemical, and physical models are needed to improve
understanding of the pressures on ecosystems and ecological responses to
climate change in the Pacific Islands region.
• A better understanding of how climate change affects invasive species and
their interactions with native species is needed.