Coordinated ENSO 97-98 Response

## A Coordinated Response to the ENSO 1997-98 with Emphasis on Ecological Impacts

Summary of a Meeting held July 11, 1997 in San Francisco

Below is the Executive Summary of a U.S. GLOBEC White Paper resulting from a one-day workshop to discuss options for coordinating more comprehensive physical and biological sampling along the west coast of North America during the El Niño that is forecast this year (see article on page 7). Adobe Acrobat and html versions of the complete white paper are available from the U.S. GLOBEC web site at:

http://www.usglobec.berkeley.edu/usglobec/enso/enso97rev01.html

http://www.usglobec.berkeley.edu/usglobec/enso/enso97rev01.pdf

Since the early 1980's, there has been marked improvement in remote sensing and modeling of El Niño's, such that it can be stated with some certainty that an El Niño will occur in 1997-1998. The evidence available to date suggests that it may be as strong or stronger than the 1982-83 El Niño. A group of oceanographers, representing a number of west coast programs, and variety of disciplines, met to develop a coordinated response of the research community to examine the propagation and impacts of this El Niño along the Pacific coast of the U.S. and Canada. The goal was to 1) provide a summary of ongoing and newly funded research/monitoring along the Pacific coast; 2) identify critical types of observations or specific regions where data are missing (gaps); and 3) provide guidance for filling those gaps. Two major goals of an enhanced monitoring program on the west coast are 1) to document the alongshore response of ocean conditions as the El Niño propagates northward along the Pacific coast of North America; and 2) to document the impacts of the anomalous conditions associated with a major El Niño on the nearshore, coastal ecosystem of the Northeast Pacific. Many of the research programs along the west coast are not directed specifically at El Niño; however, a major 1997-1998 El Niño would impact ocean conditions and ecological interactions along much of the west coast. Small changes in focus, perhaps accompanied by small, incremental enhancements of funds, could dramatically improve sampling at sites along the coast likely to be impacted by El Niño. However, in no respect should these changes be viewed as altering the fundamental long-term missions/goals of these established programs.

Four general needs of a coordinated ENSO monitoring effort are: 1) increased sampling of subsurface observations; 2) broader sampling of ocean chemistry and biology, including nutrients and multiple trophic levels; 3) sampling at many locations along the west coast, at as high a frequency as affordable; and, 4) establishment of a more effective communication network to coordinate the many sampling and monitoring activities that occur along the west coast.

Generally, we are much better placed presently to document the physical manifestation of El Niño conditions along the west coast than we are for biological aspects of the ecosystem. The network of observation sites, including moorings, NDBC buoys off California, tide gauges and shore temperature stations at a number of locations, and survey transects and grids in place now is nearly capable of documenting the physical manifestation of an El Niño as it propagates poleward along the North American west coast. If the network is supplemented in a few sites by a) beginning programs earlier than their intended starts, b) continuing existing programs beyond their scheduled completion, or c) augmenting existing programs, physical aspects of this prospective ENSO will be recorded satisfactorily. The coastwide sampling outlook is not as favorable for nutrient and biological variables. As for the physics, some improvement in chemical and biological sampling could be obtained by beginning projects prior to their official start dates. However, some regions do not have ongoing or planned sampling of biology at all, nor are there research cruises ongoing to which additional biological sampling could be added. In other regions it might be possible to obtain additional biological sampling for minimal cost, because research cruises are already taking place for other reasons.