California-Benguela Joint Investigation

CalBenJI is a major 5-year collaborative research program of the United States, South Africa, and Namibia.  The program is the first international, interdisciplinary collaboration on climate change and marine ecosystems for South Africa's newly formed Branch Oceans and Coasts of the Department of Environmental Affairs.  Through management-oriented science, comparative ecosystem research, and capacity building, marine scientists from four U.S. and three South African institutions are working together to discover how climate change is impacting the environments of the west coasts of each country.  The multidisciplinary team includes independent specialists in atmospheric science, physical oceanography, and ecology of marine organisms from plankton to top predators (seabirds and marine mammals).  The project is co-sponsored by the U.S. National Science Foundation, U.S. Department of Commerce, and the South African government. 

Over the next 5 years, researchers of the CalBenJI collaborative will assess how ocean warming (and related de-oxygenation) and other aspects of human-induced or natural climate change affect ecosystem productivity, fisheries and wildlife populations of North America’s California Current System (CCS) and Southern Africa's and Namibia's Benguela Current System (BCS).  These are 2 of the 4 Eastern Boundary Upwelling Ecosystems (EBUE) of the world; EBUE cover < 1% of the global seas yet contribute >20% of the worlds capture fisheries as well as other strategic and essential economic and ecological services to society.

What can be learned from a comparison of the California and Benguela Current Systems?

Anthropogenic global warming is a global concern, yet research on the impacts of climate change is rarely global in scale.  In EBUE, alongshore winds promote upwelling of cold, nutrient-rich waters that stimulates primary productivity and robust food webs.  It is thought that global warming will influence the location and intensity of the large-scale oceanic high pressure cells that drive alongshore winds in these systems with effects on oceanography and marine life (Figure 1).  We intend to use a comparative approach to test this complicated multi-layered hypothesis.  While the two systems are driven by similar dynamics (upwelling-favorable coastal winds), in other respects they vary greatly.  For example, the California system is strongly affected by the Pacific Ocean's tropical El Nino - Southern Oscillation (ENSO), while the Benguela system is affected by climate variability of the tropical Atlantic Ocean.  The Benguela is bounded by the warm Algulhas Current at its poleward extent, whereas the California system is bounded by the sub-arctic North Pacific Current.  Differences in internal and external forcings, as well as spatial variation in ecosystem characteristics suggest that biotic responses to climate change in these systems will vary in complex and unpredictable ways. 

Comparative analyses will reveal which influences are natural vs human caused, as well as global versus local to regional. To conduct this comparison, we will host workshops, promote staff exchanges between countries and institutions, develop collaborative peer-reviewed scientific publications, and address management needs across systems (e.g. ecological indicators of ecosystem 'health', benchmarks for fisheries, risk assessments of climate change impacts).  In this manner, CalBenJI will contribute to the scientific and management enterprises of all involved countries.