A-2. Eastern Boundary Currents
U.S. GLOBEC has published a science plan for research in the California
Current Ecosystem (U.S. GLOBEC Report No. 11, 1994). The goal of a
Califonia Current System (CCS) study is, "To understand the effects of
climate change on the distribution, abundance and production of marine
animal populations in the CCS". The approach is to study the effects of
past and present climate variability as a proxy to better understand how
the CCS may respond to future global warming and climate change.
Dominant temporal scales of variability in the CCS are interannual,
primarily due to the El Niño-Southern Oscillation linking atmospheric
and ocean dynamics, and decadal, manifest primarily as large scale
shifts in the structure (or productivity) of the system, due to large
scale shifts in the position of atmospheric cells and associated
physical forcing. In spatial terms, the dominant scales of variability
in the CCS are: first, latitudinal, with large gradients in physical
forcing and species composition from north to south; and second,
mesoscale, with prominent squirts, jets, and filaments, especially off
central and northern California. U.S. GLOBEC's research in the CCS will
focus on these temporal and spatial scales of variability. Accordingly,
we will investigate the linkage between growth, reproduction, mortality,
genetic composition, physiological condition, transport, and recruitment
of holoplankton, meroplankton, and icthyoplankton and the dominant
spatial and temporal variability of physical forcing. U.S. GLOBEC will
attempt to understand how populations adapt to the different mesoscale
dynamics that occur latitudinally in order to provide a better
indication of the consequences of climate change to the ecosystem.
Finally, we aim to better understand the abrupt shifts that occur
infrequently so that perhaps we may recognize future shifts early and
provide useful advice to managers of harvestable living marine resources
in the California Current. Table 4 contains a summary of the scientific
objectives and the approaches that will be used to meet these
objectives. A tentative schedule of activities in the CCS appears in
Table 2. More information can be obtained from U.S. GLOBEC Reports No.
7 and No. 11.
U.S. GLOBEC hopes to collaborate with other programs investigating the
California Current Ecosystem, or other EBCs. Numerous field efforts
already obtain large volumes of multidisciplinary data from the CCS.
These are mostly sponsored by NOAA, NSF, ONR, and MMS; in addition,
regular long term sampling programs are conducted by CalCOFI, NMFS,
state agencies, and numerous regional academic and research
institutions. The Coastal Ocean Processes (CoOP) program intends a
multidisciplinary study of the U.S. west coast, as a representative
example of a strongly wind-driven shelf system. CoOP and U.S. GLOBEC
have been discussing how to best collaborate to achieve more than either
program could achieve independently. Studies of other EBCs will either
be ongoing or are planned for the period when U.S. GLOBEC will be
studying the California Current ecosystem. Connections to the active
programs off South America, the west coast of Africa, South Africa
(Benguela Ecology Program-BEP), and the Iberian peninsula would be
welcome and probably best coordinated through GLOBEC International.
This offers an opportunity to undertake regional comparison to examine
EBCs having different levels of physical forcing. International
linkages will also occur through GLOBEC International's Small Pelagic
Fish and Climate Change (SPACC) initiative. Mexico and Canada conduct
frequent and regular physical and biological surveys off their west
coasts. Collaboration would greatly facilitate the regional latitudinal
comparison of biological response to mesoscale physical forcing and the
study of transition zones along the west coast.