Top PDF Marine ecosystem response to the Atlantic Multidecadal Oscillation.

Marine ecosystem response to the Atlantic Multidecadal Oscillation.

Marine ecosystem response to the Atlantic Multidecadal Oscillation.

The period of warming (warm AMO phase) from the 1930s to the 1960s had profound impacts for the fisheries of the North Atlantic from temperate shelf systems such as the North Sea to boreal and Arctic systems. The warming period caused large poleward distribution extensions of numerous marine and terrestrial species from Greenland to Iceland [11]. For example, the distribution of cod extended poleward along the coast of west Greenland by ,1000 km during this warming period and the biomass of Norwegian spring-spawning herring increased almost ten-fold [12]. Simultaneously, herring at their southerly distribu- tion in the English Channel collapsed in the early 1930s to be replaced by sardines some years later as the dominant pelagic species [1]. Conversely, when the Norwegian Sea underwent fairly rapid cooling after the late 1950s to the 1970s the herring population declined by more than four orders of magnitude (Fig. 3a). Since the mid 1990s warming event the herring spawning stock has subsequently recovered to levels similar to the mid 1960s (Fig. 3a). While acknowledging the potential contribution from recruitment overfishing [13] the underlying evidence suggests that a relatively small change in basin-scale average temperature (higher in certain regions) can trigger habitat switching where vulnerable populations are found at the extremities of their biogeographic ranges whether this is at the northern or southern limits of their distribution. The large changes in abundance and shifts in fish and plankton species observed in the English Channel between the periods 1920s and 1970s have previously been termed ‘The Russell Cycle’ [14,15]. Therefore, it appears that what has been termed the Russell Cycle in the English Channel is largely synchronous with the low frequency cyclical variability in North Atlantic SST known as the AMO signal (Fig. 3b).
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Comment on "100-year mass changes in the Swiss Alps linked to the Atlantic Multidecadal Oscillation" by Matthias Huss et al. (2010)

Comment on "100-year mass changes in the Swiss Alps linked to the Atlantic Multidecadal Oscillation" by Matthias Huss et al. (2010)

process with a response time of typically a few decades (e.g. Adhikari and Huybrechts, 2009; Brugger, 2007; Oerlemans, 1997; J ´ohannesson et al., 1989). Therefore short- term climate variations are less damped by geometric adjustment of the glacier than long-term climate variations (Fig. 1). To estimate the relative importance of short-term climate variability on the state of glaciers, variations of the reference-surface mass

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Temporal energy partitions of Florida extreme sea level events as a function of Atlantic multidecadal oscillation

Temporal energy partitions of Florida extreme sea level events as a function of Atlantic multidecadal oscillation

AWP, associated with a decrease in sea level pressure and an increase in atmospheric convection and cloudiness, corresponds to a weak tropospheric vertical wind shear and a deep warm upper ocean, and thus increases Atlantic hurricane activity”. Therefore, one can suggest a link between the AWP/increased storm activity as a forcing mech- anism and the extreme coastal water levels and durations as a response. Second, if

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The response of the Peruvian Upwelling Ecosystem to centennial-scale global change during the last two millennia

The response of the Peruvian Upwelling Ecosystem to centennial-scale global change during the last two millennia

Fig. 4. Linkage between the oxygenation in the subsurface waters and in the sediments, and the export production obtained in the present work and proxies used to infer changes in the zonal SST gradients and changes in the expansion/contraction of the South Pacific Sub Tropi- cal High (SPSH). (A) 10-point average of the northern hemisphere (NH) temperature anomaly (Mann et al., 2009). (B) Indo Pacific Warm Pool SST reconstruction (Oppo et al., 2009). (C) Eastern Equatorial Pacific SST reconstruction (ln of the number of tychoplanktonic to epiphytic diatoms in El Junco Lake, Galapagos, Conroy et al., 2009).The arrows between these two pan- els show the increased SST gradient during the MCA compared to the LIA (Conroy et al., 2010). (D) 3-point average of Fe intensity in a marine sediment core off Chile (∼ 41 ◦ S), where lower
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Selection of the temperature of casting the bronzes to plaster moulds

Selection of the temperature of casting the bronzes to plaster moulds

dependence from the temperature of casting the bronze to the mould on Figure 6. From the introduced cross - section of casts from the probe TDAg, it results that it together with considerably grows up the depth of the contraction cavity with the growth of the temperature of casting, and what joins with this executed along its axis the volumetric contraction grows up, especially bronze B555 (Fig. 5a and 6). The bronze B10 is characterizes considerably smaller volumetric contraction (Fig. 5b and 6), however overheated 1180 °C above and cast to the hot plaster mould, in the conditions of the atmospheric pressure, it undergoes strong gassing with what considerable decrease of the depth of the contraction cavity joins (Fig. 5b 1200 ° C and Fig . 6). Zinc as high active metal in the relation of oxygen influences the lower- ing of the content of gases dissolved in the bronze B555. Consid- erably larger content Zn in the chemical composition of the bronze B555 (approx. 5%), in the comparison with the bronze B10 (to 0.5 %), it favours creation on the surface of the solidifica- tion bronze of the layer of oxides Zn and Cu, in the composition natural slags about the smaller mass density from the liquid bronze, making difficult chemical adsorption and dissolving the hydrogen and oxygen in the liquid bronze. Bronze B10 including first of all the admixture approx. 10% Sn, element of little active in the relation to oxygen, it absorbs from surroundings highly both the hydrogen as and the oxygen, what it brings in the conse- quence, together with the growth of the temperature of casting, to gassing the bronze.
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Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom <i>Fragilariopsis cylindrus</i>

Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom <i>Fragilariopsis cylindrus</i>

with some strains being unaffected and others being positively or negatively affected by temperature changes (Kremp et al., 2012). The present study confirms previous no- tion of high intra-specific variability within species, and emphasizes, that this variation might be even larger than the variation observed due to changing environmental fac- tors, stressing the need for several strains when exploring the environmental effects on

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Braz. j. oceanogr.  vol.58 número1

Braz. j. oceanogr. vol.58 número1

Abudefduf saxatilis is a small sized (about 20 cm max. total length, TL) omnivorous fish that ranks among the three most abundant reef fish species at the sites studied (MOURA; FRANCINI-FILHO, 2006), having accounted for most records of zoanthid predation (n = 28). Cantherhines macrocerus accounted for 14 zoanthid predation events, while P. paru and P. arcuatus accounted for 8 and 4 of such records, respectively (Table 1). Although P. arcuatus and P. paru are not numerically dominant they are large-sized (ca. 50 cm max. TL) and conspicuous elements of the reef fish assemblage, composing 5.1 and 4.7%, respectively, of the total reef fish biomass in the study region (FRANCINI-FILHO; MOURA, 2008). Cantherhines macrocerus is also relatively large (about 45 cm max. TL), but is much rarer (< 0.1% of reef fish biomass). Predation was undertaken by groups of 3-8 A. saxatilis individuals (Fig. 1) and by single individuals or pairs of C. macrocerus, P. arcuatus and P. paru. These latter three species took only a single or a few bites and then moved away from the zoanthid colonies, while groups of A. saxatilis took repeated and overlapping bites from the same colonies, causing larger lesions (Fig. 1). Predation was always concentrated on tissue that was previously undamaged and not bleached nor diseased (see ACOSTA, 2001). Table 1. Number of records of zoanthid (Palythoa caribaeorum) predation by reef fishes at three sites within the Abrolhos Bank. Sampling sites: PAAB – Parcel dos Abrolhos, AREN – Arenguera and PNOR – Portinho Norte (within the Abrolhos Archipelago).
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Porting marine ecosystem model spin-up using transport matrices to GPUs

Porting marine ecosystem model spin-up using transport matrices to GPUs

multiplications on distributed memory hardware using MPI. For this purpose, we use the PETSc library. The main advantages of this toolkit is that all MPI calls are hidden in built-in functions, and that optimized functions for matrix-vector operations (and more) already exist. The resulting software can be coupled with a wide range of biogeochem- ical models, as long as they conform with a rather flexible and general interface.

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Lost fishing gear and litter at Gorringe Bank (NE Atlantic)

Lost fishing gear and litter at Gorringe Bank (NE Atlantic)

Marine litter; Fisheries; impacts; Gorringe Bank; NE Atlantic; seamounts... The Gettysburg and Ormonde seamounts, forming 48.[r]

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Oxygenation variability off Northern Chile during the last two centuries

Oxygenation variability off Northern Chile during the last two centuries

bottom-water oxygenation proxies analyzed in this work provide evidence to confirm the hypothesis proposed by Vargas et al. (2007) that the marine coastal ecosystem off Northern Chile has experienced a shift since the mid 19th century towards increased biological productivity due to stronger upwelling favorable winds (i.e. increased input of Ti and Zr, Fig. 4d). Moreover, the record of proxies presented indicates that the

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Fishers' behaviour in response to the implementation of a Marine Protected Area.

Fishers' behaviour in response to the implementation of a Marine Protected Area.

Marine Protected Areas (MPAs) have been widely proposed as a fisheries management tool in addition to their conservation purposes. Despite this, few studies have satisfactorily assessed the dynamics of fishers’ adaptations to the loss of fishing grounds. Here we used data from before, during and after the implementation of the management plan of a temperate Atlantic multiple-use MPA to examine the factors affecting the spatial and temporal distribution of different gears used by the artisanal fishing fleet. The position of vessels and gear types were obtained by visual surveys and related to spatial features of the marine park. A hotspot analysis was conducted to identify heavily utilized patches for each fishing gear and time period. The contribution of individual vessels to each significant cluster was assessed to better understand fishers’ choices. Different fisheries responded differently to the implementation of protection measures, with preferred habitats of target species driving much of the fishers’ choices. Within each fishery, individual fishers showed distinct strategies with some operating in a broader area whereas others kept preferred territories. Our findings are based on reliable methods that can easily be applied in coastal multipurpose MPAs to monitor and assess fisheries and fishers responses to different management rules and protection levels. This paper is the first in-depth empirical study where fishers’ choices from artisanal fisheries were analysed before, during and after the implementation of a MPA, thereby allowing a clearer understanding of the dynamics of local fisheries and providing significant lessons for marine conservation and management of coastal systems.
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Organic compounds in marine sediments: a journey to the bottom of the North Atlantic Ocean.

Organic compounds in marine sediments: a journey to the bottom of the North Atlantic Ocean.

O teor de carbono orgânico (Corg) também acompanha essa mesma tendência. Portanto, basea- do no que foi discutido sobre as possíveis fontes e a abundância dos compostos orgânicos nos sed[r]

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Puzzling Out Ecosystem Services Values: A Participatory Framework to Support Decision- Making

Puzzling Out Ecosystem Services Values: A Participatory Framework to Support Decision- Making

The use of multi-criteria analysis techniques was proposed in the study from Esse et al. (2014). Due to its capacity to assess trade-offs and accommodate value pluralism, multi-criteria analysis has showed promising results as a method for integrated valuation of ES (Langemeyer et al., 2016). Several other examples may be found in the literature where multi-criteria analysis has been used in ES assessments (Seidl and Lexer, 2013; Fontana et al., 2013; Nordstrom et al., 2011; Grazhdani, 2014). Langemeyer et al. (2016) analysed multi-criteria processes involving ES observing that many studies differentiate the alternatives spatially. However, lack of information on context-specific ES data was a challenge highlighted when conducting multi- criteria analysis on ES (Langemeyer et al., 2016). Other contested issues that may arise during the implementation of these methods include the choice of aggregation rules, trading-off incommensurable values, or increasing the risk of under representation of minority goals (Langemeyer et al., 2016). One way to overcome some of these issues is combining participation with multicriteria analysis. Typically, when conducting multi-criteria analysis in participatory contexts stakeholders are asked to discuss and explore different criteria, alternatives and weights (e.g., Antunes et al., 2011). For example, Acosta and Corral (2015) conducted a participatory multi-criteria assessment of forest planning policies with regard to conflicting situations and Salgado et al. (2009) combined multi-criteria with social research techniques for the evaluation of urban water supply alternatives. Carnoye and Lopes (2015) compared cases applying four different valuation methods revealing the achieved gains when combining participatory techniques in multi-criteria analysis with regard to cognitive (e.g., invisibility) and normative problems (e.g., incommensurability), since these processes allow to make problem structuring more explicit by providing time for sharing perceptions without forcing trade-offs across value domains.
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Evaluation of marine subareas of Europe using life history parameters and trophic levels of selected fish populations

Evaluation of marine subareas of Europe using life history parameters and trophic levels of selected fish populations

The effects of global climatic changes on the marine environ- ment and fish populations are also known to occur ( Stenevik and Sundby, 2007; Elliott et al., 2015). All the seas in Europe are threatened by climate change (Conversi et al., 2010; Reid and Valdes, 2011) and anthropogenic pressures are altering the key environmental variables supporting fish life, such as temperature, winds, water mixing, oxygen, pH and oxygen, (Brander, 2010; Gattuso et al., 2015). These alterations directly affect physiology, development rates, reproduction, behavior and survival rates of larvae and fishes ( Brander, 2010; EEA, 2015). As such, life history parameters and fish catches, which are main data sources for the present analysis can also be affected by these altered climatic conditions. In addition, the marine food web structure and trophic levels may also alter due to climate change (Muren et al., 2005; Cury et al., 2008). However, the time series analysis for MTL in this study was done only for 1998 to 2013, which is insuf ficient to detect the impact of climatic change. Nevertheless, the above evi- dence suggests that future directions towards qualitative assess- ment of the status of European seas should be viewed through the climate change scenarios.
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Incorporation of Socio-Economic Features' Ranking in Multicriteria Analysis Based on Ecosystem Services for Marine Protected Area Planning.

Incorporation of Socio-Economic Features' Ranking in Multicriteria Analysis Based on Ecosystem Services for Marine Protected Area Planning.

It is clear that not all MPAs in the Mediterranean Sea have developed management plans, not all management plans include zoning and lastly, many management plans exist but are not well implemented or enforced [8, 67]. Yet through the use of MCA for the design of zoning within an MPA, planners have a number of different scenarios to consider that would be acceptable to user groups and likely supported. However, further research efforts are needed to render this type of MCA, so dependent on resource user valuation, capable of incorporating socio-economic values based on ES away from the shore in areas of low accessibility and low familiarity. Therefore, an aim of research taking place to improve the incorporation of the eco- systems services approach in decision making (e.g., [39]), especially with regards to the marine environment, should improve knowledge of ES values at significant distances from shore.
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Reconsidering the role of carbonate ion concentration in calcification by marine organisms

Reconsidering the role of carbonate ion concentration in calcification by marine organisms

have to be transported in a series of active and/or passive processes until they reach the site of calcification which is usually located in specialized cellular compartments, tissues, or tissue interfaces. Transport mechanisms and pathways are highly diverse among the various calcifying taxa which rules out the possibility to formulate a generally applicable calcification model (Mann, 2001). What all calcifiers have in common, how-

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Geo-Referenced, Abundance Calibrated Ocean Distribution of Chinook Salmon (Oncorhynchus tshawytscha) Stocks across the West Coast of North America.

Geo-Referenced, Abundance Calibrated Ocean Distribution of Chinook Salmon (Oncorhynchus tshawytscha) Stocks across the West Coast of North America.

The Pacific Fishery Management Council (PFMC) develops management measures for Chi- nook salmon ocean fisheries in the southern portion of the California Current large marine ecosystem, United States of America (USA) [10]. A single-season modeling tool called the “Fishery Regulation Assessment Model” (FRAM) is used by the PFMC to predict cohort-based stock abundance and time and area stock compositions [11]. Using those modeled data, fishery harvest scenarios are analyzed to assess impacts to stocks, with the end goal of maximizing har- vest while meeting conservation targets. This model relies heavily on mark and recapture data from mostly hatchery fish implanted with coded-wire-tags (CWT) that indicate source stock and cohort year [12,13]. Fish are sampled when landed at port or on return to hatcheries. The CWT recoveries are expanded by sampling (usually about 20%) and marking rates (usually about 5%) to estimate the number of tagged and untagged fish from each mark group in the modeled fishery [13]. CWT release groups are often used as “indicator stocks” for unmarked natural production. The FRAM model assumes (see model documentation for a full list) that sampling for CWTs is random, that CWT fish accurately represent the modeled stock, and that stock distributions and migratory timings are constant from year to year. However, mark selec- tive fisheries implemented in recent years require the release of some fish. Furthermore, evi- dence is accumulating that some hatchery fish are less fit than their wild stock counterparts [14,15], and spatial and temporal fluctuations in marine environmental conditions influence stock distribution and survival [16–18]. Perhaps the most troubling aspect of modeling fisher- ies with CWT data is the delay in compiling all the recovery data required to reconstruct
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Modelling the impact of deep-water crustacean trawl fishery in the marine ecosystem off Portuguese Southwestern and South Coasts: I) the trophic web and trophic flows

Modelling the impact of deep-water crustacean trawl fishery in the marine ecosystem off Portuguese Southwestern and South Coasts: I) the trophic web and trophic flows

In particular, we characterize the structure and resilience of the southern Portuguese marine ecosystem by describing the food web structure and functioning, identifying the main keyston[r]

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Satellite observations reveal high variability and a decreasing trend in CO<sub>2</sub> fluxes on the Scotian Shelf

Satellite observations reveal high variability and a decreasing trend in CO<sub>2</sub> fluxes on the Scotian Shelf

Hales, B., Friederich, G., Chavez, F., Sabine, C., Watson, A., Bakker, D. C., Schuster, U., Metzl, N., Yoshikawa-Inoue, H., Ishii, M., Midorikawa, T., Nojiri, Y., K ¨ortzinger, A., Stein- hoff, T., Hoppema, M., Olafsson, J., Arnarson, T. S., Tilbrook, B., Johannessen, T., Olsen, A., Bellerby, R., Wong, C., Delille, B., Bates, N., and de Baar, H. J.: Climatological mean and decadal changes in surface ocean pCO 2 , and net sea-air CO 2 flux over the global oceans,

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Assessment of sea surface temperature changes in the Gulf of Cadiz during the last 30 ka: Implications for glacial changes in the regional hydrography

Assessment of sea surface temperature changes in the Gulf of Cadiz during the last 30 ka: Implications for glacial changes in the regional hydrography

The first transfer function used in this work (de Vernal et al., 2005; GEOTOP website: http://www.unites.uqam.ca/ geotop/monographie n940/eng/index.shtml) is derived from a modern database comprising 60 dinocyst species and 940 stations from the North Atlantic, Arctic and North Pacific oceans and their adjacent seas, including the Mediterranean Sea, as well as epicontinental environments such as the Es- tuary and Gulf of St. Lawrence, the Bering Sea and the Hudson Bay. The transfer function (n = 940) is run under the “3Pbase” software (Guiot and Goeury, 1996). Hydro- logical parameters are systematically calculated on the basis of the 5 best analogues found by the transfer function. An index “Dmin”, provided by the “3PBase” software, allows testing the reliability of the reconstructions. This index de- scribes, for each sample analyzed, the distance between the closest analogue found by the transfer function and the fossil assemblage. A threshold value is calculated from the cali- bration of the database for the identification of non-similar or very bad analogues. The similarity between the modern data and the fossil record is considered significant below the threshold value of 71.72 (de Vernal et al., 2005). With the n = 940 transfer function implemented with the “3PBase” software (i.e. 3PBase-940), we present February and August mean sea-surface temperatures (SSTs) with prediction errors of ± 1.2 ◦ C and ±1.8 ◦ C, respectively.
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