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Robert C. Francis

Bio: Robert C. Francis is an academic researcher from University of Washington. The author has contributed to research in topics: Ecosystem & Marine ecosystem. The author has an hindex of 29, co-authored 43 publications receiving 9789 citations. Previous affiliations of Robert C. Francis include National Oceanic and Atmospheric Administration.

Papers
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Journal ArticleDOI
TL;DR: In this article, the authors identify a robust, recurring pattern of ocean-atmosphere climate variability centered over the midlatitude North Pacific basin over the past century, the amplitude of this climate pattern has varied irregularly at interannual-to-interdecadal timescales.
Abstract: Evidence gleaned from the instrumental record of climate data identifies a robust, recurring pattern of ocean–atmosphere climate variability centered over the midlatitude North Pacific basin. Over the past century, the amplitude of this climate pattern has varied irregularly at interannual-to-interdecadal timescales. There is evidence of reversals in the prevailing polarity of the oscillation occurring around 1925, 1947, and 1977; the last two reversals correspond to dramatic shifts in salmon production regimes in the North Pacific Ocean. This climate pattern also affects coastal sea and continental surface air temperatures, as well as streamflow in major west coast river systems, from Alaska to California.

6,719 citations

Journal ArticleDOI
TL;DR: In this article, the authors examine rapid decadal-scale shifts in the abundance and distribution of two major components of the large marine ecosystem of the North-east Pacific, and how they relate to similar shifts in North Pacific atmosphere and ocean climate.
Abstract: There are two fundamental ways of doing science: the experimental-predictive and the historical-descriptive. The experimental-predictive approach uses the techniques of controlled experiment, the reduction of natural complexity to a minimal set of general causes, and presupposes that all times can be treated alike and adequately simulated in the laboratory. The historical-descriptive approach uses a mode of analysis which is rooted in the comparative and observational richness of our data, is holistic in its treatment of systems and events, and assumes that the final result being studied is unique, i.e. dependent or contingent upon everything that came before. We suggest that one of the real difficulties we have in understanding ecosystem properties is our inability to deal with scale, and we show how historical science allows us to approach the issue of scale through the interpretation of pattern in time and space. We then use the techniques of the historical-descriptive approach to doing science in the context of our own and other research on climate change and biological production in the North-east Pacific Ocean. In particular, we examine rapid decadal-scale shifts in the abundance and distribution of two major components–salmon and zooplankton - of the large marine ecosystem of the North-east Pacific, and how they relate to similar shifts in North Pacific atmosphere and ocean climate. We conclude that they are all related, and that climate-driven regime shifts, such as those we have identified in the North-east Pacific, can cause major reorganizations of ecological relationships over vast oceanic regions.

501 citations

Journal ArticleDOI
TL;DR: In this article, the effects of interdecadal climate forcing on the oceanic ecosys-tems of the NE Pacific Ocean were investigated and the con-cept of scale in terms of both time and space with the North Pacific ecosystem was considered.
Abstract: A major reorganization of the North-east Pacific biotatranspired following a climatic ‘regime shift’ in the mid1970s. In this paper, we characterize the effects ofinterdecadal climate forcing on the oceanic ecosys-tems of the NE Pacific Ocean. We consider the con-cept of scale in terms of both time and space withinthe North Pacific ecosystem and develop a conceptualmodel to illustrate how climate variability is linked toecosystem change. Next we describe a number of re-cent studies relating climate to marine ecosystem dy-namics in the NE Pacific Ocean. These studies havefocused on most major components of marine ecosys-tems – primary and secondary producers, forage spe-cies, and several levels of predators. They have beenundertaken at different time and space scales. How-ever, taken together, they reveal a more coherentpicture of how decadal-scale climate forcing may affectthe large oceanic ecosystems of the NE Pacific. Finally,we synthesize the insight gained from interpretingthese studies. Several general conclusions can bedrawn.1 There are large-scale, low-frequency, and some-times very rapid changes in the distribution of atmo-spheric pressure over the North Pacific which are, inturn, reflected in ocean properties and circulation.2 Oceanic ecosystems respond on similar time andspace scales to variations in physical conditions.3 Linkages between the atmosphere/ocean physicsand biological responses are often different across timeand space scales.4 While the cases presented here demonstrateoceanic ecosystem response to climate forcing, theyprovide only hints of the mechanisms of interaction.5 A model whereby ecosystem response to specifiedclimate variation can be successfully predicted will bedifficult to achieve because of scale mismatches andnonlinearities in the atmosphere–ocean–biospheresystem.INTRODUCTIONIn this paper, we characterize the effects of interde-cadal climate forcing on the oceanic ecosystems of theNE Pacific Ocean. Our approach is first to reflect on anumber of recent studies relating climate to marineecosystem dynamics. These studies have focused onmost major components of marine ecosystems – pri-mary and secondary producers; primary, secondary andtop-level predators. They have been undertaken atdifferent time and space scales. However, taken to-gether they begin to reveal a more coherent picture ofhow decadal-scale climate forcing may affect the largeoceanic ecosystems of the NE Pacific. We then syn-thesize the insight gained from these studies with whatwe know about atmospheric and oceanic physics andhow they affect these marine ecosystems.Of particular importance to this paper is the con-cept of scale. Ricklefs (1990) defines scale as thecharacteristic distance or time associated with varia-tion in natural systems. He goes on to make threeimportant points about why the concept of scale is soimportant to developing an understanding of ecosys-tem structure and dynamics.Every process and pattern has a temporal andspatial extent.

455 citations

Journal ArticleDOI
TL;DR: A principal component analysis revealed that Pacific salmon catches in Alaska have varied inversely with catches from the U.S. West Coast during the past 70 years as mentioned in this paper, suggesting that the spatial and temporal characteristics of this "inverse" catch/production pattern are related to climate forcing associated with the Pacific Decadal Oscillation, a recurring pattern of pan-Pacific atmosphere-ocean variability.
Abstract: A principal component analysis reveals that Pacific salmon catches in Alaska have varied inversely with catches from the U.S. West Coast during the past 70 years. If variations in catch reflect variations in salmon production, then results of our analysis suggest that the spatial and temporal characteristics of this “inverse” catch/production pattern are related to climate forcing associated with the Pacific Decadal Oscillation, a recurring pattern of pan-Pacific atmosphere-ocean variability. Temporally, both the physical and biological variability are best characterized as alternating 20-to 30-year-long regimes punctuated by abrupt reversals. From 1977 to the early 1990s, ocean conditions have generally favored Alaska stocks and disfavored West Coast stocks. Unfavorable ocean conditions are likely confounding recent management efforts focused on increasing West Coast Pacific salmon production. Recovery of at-risk (threatened and endangered) stocks may await the next reversal of the Pacific Decad...

384 citations

Journal ArticleDOI
TL;DR: In an effort to accelerate the ongoing paradigm shift in fisheries science from the traditional single-species mindset toward more ecosystem-based approaches, the authors offer the following "commandments" as action items for bridging the gap between general principles and specifie methodologies.
Abstract: In an effort to accelerate the ongoing paradigm shift in fisheries science from the traditional single-species mindset toward more ecosystem-based approaches, we offer the following “commandments” as action items for bridging the gap between general principles and specifie methodologies. 1. Keep a perspective that is holistic, risk-averse, and adaptive. 2. Question key assumptions, no matter how basic. 3. Maintain old-growth age structure in fish populations. 4. Characterize and maintain the natural spatial structure of fish stocks. 5. Characterize and maintain viable fish habitats. 6. Characterize and maintain ecosystem resilience. 7. Identify and maintain critical food web connections. 8. Account for ecosystem change through time. 9. Account for evolutionary change caused by fishing. 10. Implement an approach that is integrated, interdisciplinary, and inclusive. Although the shift in worldview embodied in these commandments can occur immediately without additional funding, full implementation o...

259 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, the authors identify a robust, recurring pattern of ocean-atmosphere climate variability centered over the midlatitude North Pacific basin over the past century, the amplitude of this climate pattern has varied irregularly at interannual-to-interdecadal timescales.
Abstract: Evidence gleaned from the instrumental record of climate data identifies a robust, recurring pattern of ocean–atmosphere climate variability centered over the midlatitude North Pacific basin. Over the past century, the amplitude of this climate pattern has varied irregularly at interannual-to-interdecadal timescales. There is evidence of reversals in the prevailing polarity of the oscillation occurring around 1925, 1947, and 1977; the last two reversals correspond to dramatic shifts in salmon production regimes in the North Pacific Ocean. This climate pattern also affects coastal sea and continental surface air temperatures, as well as streamflow in major west coast river systems, from Alaska to California.

6,719 citations

Journal ArticleDOI

6,278 citations

Journal ArticleDOI
27 Jul 2001-Science
TL;DR: Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of over-fished species until they too were overfished or died of epidemic diseases related to overcrowding as mentioned in this paper.
Abstract: Ecological extinction caused by overfishing precedes all other pervasive human disturbance to coastal ecosystems, including pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of large consumer species were fantastically large in comparison with recent observations. Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of overfished species until they too were overfished or died of epidemic diseases related to overcrowding. Retrospective data not only help to clarify underlying causes and rates of ecological change, but they also demonstrate achievable goals for restoration and management of coastal ecosystems that could not even be contemplated based on the limited perspective of recent observations alone.

5,411 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provide a review of fundamental concepts of drought, classification of droughts, drought indices, historical Droughts using paleoclimatic studies, and the relation between DAs and large scale climate indices.

3,352 citations

Journal ArticleDOI
23 Jun 2006-Science
TL;DR: Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed >65% of seagrass and wetland habitat, degraded water quality, and accelerated species invasions.
Abstract: Estuarine and coastal transformation is as old as civilization yet has dramatically accelerated over the past 150 to 300 years. Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed >65% of seagrass and wetland habitat, degraded water quality, and accelerated species invasions. Twentieth-century conservation efforts achieved partial recovery of upper trophic levels but have so far failed to restore former ecosystem structure and function. Our results provide detailed historical baselines and quantitative targets for ecosystem-based management and marine conservation.

2,795 citations