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Research Priority 12: Understand the impact of climate variability and
change on the biogeochemistry of the ocean and implications for its
ecosystems.
Changes in physical properties of the ocean (e.g., heat, freshwater and circulation), as well
as biogeochemical properties (e.g., carbon, nitrogen, dust, trace elements, pollutants), can
have a variety of impacts, particularly on ecosystems, ranging from coastal watersheds, to
shallow and deep-water coral reefs, to open-ocean systems. For example, increasing ocean
acidity, altered biogeochemistry, changing current patterns, loss of sea ice, rising sea levels,
and modified salinity and sea-surface temperature may irreversibly alter ecosystems. Sustained
observations (e.g., global and coastal observatories), process research (e.g., air-sea
exchange, ecosystem interactions) and modeling (e.g., coupled models integrating global
and regional biological, chemical, and physical data) will help determine fluxes and cycling
of biogeochemical variables and help identify and quantify impacts on ecosystems of
the greatest importance. These efforts will also help identify subsequent feedbacks regarding
the influence of ecosystems on climate (e.g., influence of ocean acidification on carbon
uptake and sequestration, desertification, increasing iron dust and subsequent oceanic
algal blooms). This effort will serve to support effective management of these ecosystems
so that they remain healthy and viable, in conjunction with research examining impacts to
and influences on ecosystem health.
Research Priority 13: Apply understanding of the ocean to help project
future climate changes and their impacts.
The ocean is getting warmer, more freshwater is being added by melting ice sheets, and
more CO 2
is being absorbed from the atmosphere. The ability to predict the timing and
magnitude of climate changes due to these and other processes and to understand how
such changes will impact society will be enhanced by quantifying the predictability of
these processes and increasing temporal and spatial resolution and dynamical complexity
of global ocean models. Integrating expanded global and regional ocean observations,
coordinated paleoceanographic data and assessments, and enhanced process research into
global coupled ocean-ice-atmosphere-land climate models will help determine the past
and present influence of ocean processes on climate change, including the potential for
rapid or abrupt change (e.g., “tipping points”). Coupled climate models will support improved
short-term predictions (e.g., hurricane intensity) and long-term projections (e.g.,
sea-level rise) that will enable local, tribal, state, regional, and federal policy- and decision-makers
to plan for and adapt to effects of climate change.
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