Executive Summary
High resolution holocene paleoclimatic and paleoceanographic
records from small lakes and anoxic basins along the British Columbia
coast.
Earth's climate is highly variable, and this natural variability
must be understood if reliable predictions of future climate states
are to be made. Geological and historical records from coastal B.C.
provide clear evidence that the regional climate has oscillated
on a variety of time-scales during the Holocene interglacial (0-10,000
years before present). The present climate of the west coast of
Canada is influenced by the Aleutian Low, the Jet Stream, and El
Niño/La Niña, which are interdependent and have sub-decadal
cycles. Superimposed in these are less well understood, longer-scale
events operating on a global scale. The interactions of these climate-forcing
phenomena determine whether there will be costly droughts or flooding
on land, and influence recruitment to many BC fisheries. The purpose
of this research is to identify past changes in atmospheric and
ocean conditions, and the relative timing of these changes, over
the last 2,000 years from the sedimentary record in coastal BC inlets
and lakes. This information is required by policy makers attempting
to recognize and adapt to anthropogenic climate change. Recognition
of the natural climatic cycles affecting the coastal ocean will
also enable the commercial marine fishing industry to respond more
strategically to natural variations in fish stocks.
Bottom sediments of inlets along southern Vancouver Islandcontain
a high-resolution record of climate change and paleoproductivity
in the North American Upwelling Domain throughout the late Holocene,.
A reconnaissance cruise aboard the CCGS Vector in August 2000 found
additional inlets with annually laminated sediments in Smith, Seymore,
and Belize inlets and Frederick Sound, in the Coastal Transition
Domain. We will sample all these sites, together with adjacent lakes,
and utilize a combination of oceanographic, sedimentological, geochemical,
and micropaleontological methods to identify and correlate long
and short-term climate cycles, impossible to resolve with the short,
approximately 100-year instrument record. We will also determine
the impact of coastal marine climate changes on the productivity
and distribution of pelagic fish stocks along the B.C. coast by
examining fish scales that are well preserved in core samples.
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