Francisco Rey | Insitute of Marine Research (original) (raw)
Papers by Francisco Rey
ICES Journal of Marine Science, 1994
ICES Journal of Marine Science, 2012
Since 1990, a decline in silicate concentrations together with increasing salinities has been obs... more Since 1990, a decline in silicate concentrations together with increasing salinities has been observed in the Atlantic water of the Norwegian and Barents Seas. This decline in silicate has been found to be related to the relative proportion in which eastern and western source water masses from the northeastern North Atlantic enter the Norwegian Sea.
Journal of General Microbiology, 1979
Glucose repressed the synthesis of 1,3-/?-glucanase in Neurospora crassa. The production of enzym... more Glucose repressed the synthesis of 1,3-/?-glucanase in Neurospora crassa. The production of enzyme during growth in glucose-supplemented medium was negligible, but if deprived of carbon source the fungus actively synthesized high levels of enzyme when growth ceased. Similar results were obtained for 1,6-P-glucanase but less enzyme was produced. A different pattern of production of these enzymes was found in Trichoderma viride and Saccharomyces cerevisiae. The enzymes were produced in glucose-supplemented medium with increasing specific activity during growth. Resting cells deprived of glucose either failed to produce /?-glucanases or produced them in smaller quantities.
Marine Chemistry, Mar 1, 2001
Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gi... more Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gimsøy-NW section from 67.58N 98E to 71.58N 18E and the Bjørnøya-W section along 74.58N from 7 to 158E, are used to estimate oxygen fluxes in the surface layer and between the atmosphere and the ocean. Vertical entrainment velocities of 0.9 m day y1 for the winter season and 0.1 m day y1 for the summer season are found and applied to the upper 300 m. The resulting oxygen fluxes to the surface layer driven by this vertical mixing are 0.58 " 0.05 and 0.27 " 0.02 mol O m y2 year y1 at the Gimsøy-NW and 2 Bjørnøya-W sections, respectively. Oxygen fluxes to the surface layer due to phytoplankton production are 2.6 and 3.4 mol O m y2 year y1 , which represent the net community production at the two sections. Estimated uncertainties in these 2 numbers are "15%. The surface water is a sink for atmospheric oxygen during fall and winter and a source during the productive season for both sections. On an annual basis there is a net uptake of oxygen from the atmosphere, 3.4 " 0.4 mol O m y2 year y1 at the Gimsøy-NW section and 4.9 " 0.5 mol O m y2 year y1 at the Bjørnøya-W. A decrease in 2 2 temperature of 18C to 1.58C seen between the Gimsøy-NW section and the Bjørnøya-W section is the main reason for the increased atmospheric flux of oxygen at the latter section. An oxygen budget made for the area bounded by the two sections gives a net advective flux of oxygen out of the area of approximately 10 mol O m y2 year y1 . The increased concentration 2 of oxygen corresponding to the decrease in surface layer temperatures going northwards in the Norwegian Atlantic Current is mainly attributed to the air-sea oxygen exchange and phytoplankton production in this area. q
Earth System Science Data, 2009
... Earth Syst. Sci. Data, 1, 2534, 2009 www.earth-syst-sci-data.net/1/25/2009/ Page 3. A. Olsen... more ... Earth Syst. Sci. Data, 1, 2534, 2009 www.earth-syst-sci-data.net/1/25/2009/ Page 3. A. Olsen et al.: Overview of the Nordic Seas CARINA data and salinity measurements 27 45 o W 30 oW 15oW 0o 15 o E 30 o E 60 o N 65 o N 70 o N 75 o N 80 o N 85 o N ...
Geophysical Monograph Series, 2000
Studies of the inorganic carbon cycle have been performed in the Nordic Seas and the Barents Sea ... more Studies of the inorganic carbon cycle have been performed in the Nordic Seas and the Barents Sea since the 1980's. Here we present a review over current knowledge on carbon transport between the different reservoirs in the area, and the transformation of inorganic carbon to organic matter. The carbon transport and transformation are closely related to other biogeochemical processes in
The Northern North Atlantic, 2001
Tellus B, 2000
... to 1997. f CO 2 record used for the different years is the annual record of 1992 at weather s... more ... to 1997. f CO 2 record used for the different years is the annual record of 1992 at weather station ''Mike'' (Conway et al., 1994) plus 1.6 matm per year in 5. Airsea exchange ... approach is negligible in relation to the Df CO 2 , speed, plus some parameters related to the proper-...
Polar Research, 1991
An analysis is made of the photosynthesis-irradiance relationships in natural phytoplankton popul... more An analysis is made of the photosynthesis-irradiance relationships in natural phytoplankton populations in the Barents Sea. The data set comprises 232 experiments carried out during a 10-year period, both in open and ice-covered waters. The variability on the P-1 parameters is discussed and examined in relation to the variation in a variety of environmental conditions. The results suggest that in the Barents Sea. as in other Arctic areas, phytoplankton photosynthesis is mainly controlled by physical variables. However, control of the phytoplankton stock. i.e. by zooplankton grazing, seems also to have a considerable indirect influence on P-I parameters, especially after the spring bloom and the depletion of winter nutrients.
The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea ... more The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea since the late 1990s are examined using remote sensing data, observations and a coupled physical-biological model. Field observations of mesozooplankton biomass, and chlorophyll a data from transects (different seasons) and large-scale surveys (autumn) were used for validation of the remote sensing products and modeling results. The validation showed that satellite data are well suited to study temporal and spatial dynamics of chlorophyll a in the Barents Sea and that the model is an essential tool for secondary production estimates. Temperature, open water area, chlorophyll a, and zooplankton biomass show large interannual variations in the Barents Sea. The climatic variability is strongest in the northern and eastern parts. The moderate increase in net primary production evident in this study is likely an ecosystem response to changes in climate during the same period. Increased open water area and duration of open water season, which are related to elevated temperatures, appear to be the key drivers of the changes in annual net primary production that has occurred in the northern and eastern areas of this ecosystem. The temporal and spatial variability in zooplankton biomass appears to be controlled largely by predation pressure. In the southeastern Barents Sea, statistically significant linkages were observed between chlorophyll a and zooplankton biomass, as well as between net primary production and fish biomass, indicating bottom-up trophic interactions in this region.
Marine Chemistry, 2007
The seasonal and interannual variability of the air–sea CO2 flux (F) in the Atlantic sector of th... more The seasonal and interannual variability of the air–sea CO2 flux (F) in the Atlantic sector of the Barents Sea have been investigated. Data for seawater fugacity of CO2 (fCO2sw) acquired during five cruises in the region were used to identify and validate an empirical procedure to compute fCO2sw from phosphate (PO4), seawater temperature (T), and salinity (S). This procedure was
Marine Chemistry, 2001
Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gi... more Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gimsøy-NW section from 67.58N 98E to 71.58N 18E and the Bjørnøya-W section along 74.58N from 7 to 158E, are used to estimate oxygen fluxes in the surface layer and between the atmosphere and the ocean. Vertical entrainment velocities of 0.9 m day y1 for the winter season and 0.1 m day y1 for the summer season are found and applied to the upper 300 m. The resulting oxygen fluxes to the surface layer driven by this vertical mixing are 0.58 " 0.05 and 0.27 " 0.02 mol O m y2 year y1 at the Gimsøy-NW and 2 Bjørnøya-W sections, respectively. Oxygen fluxes to the surface layer due to phytoplankton production are 2.6 and 3.4 mol O m y2 year y1 , which represent the net community production at the two sections. Estimated uncertainties in these 2 numbers are "15%. The surface water is a sink for atmospheric oxygen during fall and winter and a source during the productive season for both sections. On an annual basis there is a net uptake of oxygen from the atmosphere, 3.4 " 0.4 mol O m y2 year y1 at the Gimsøy-NW section and 4.9 " 0.5 mol O m y2 year y1 at the Bjørnøya-W. A decrease in 2 2 temperature of 18C to 1.58C seen between the Gimsøy-NW section and the Bjørnøya-W section is the main reason for the increased atmospheric flux of oxygen at the latter section. An oxygen budget made for the area bounded by the two sections gives a net advective flux of oxygen out of the area of approximately 10 mol O m y2 year y1 . The increased concentration 2 of oxygen corresponding to the decrease in surface layer temperatures going northwards in the Norwegian Atlantic Current is mainly attributed to the air-sea oxygen exchange and phytoplankton production in this area. q
Sarsia: North Atlantic Marine Science, 2003
ABSTRACT Analysis of data obtained by the Institute of Marine Research, Norway, at their regular ... more ABSTRACT Analysis of data obtained by the Institute of Marine Research, Norway, at their regular surveys of the Fugløya-Bjørnøya section, between the northern tip of Norway and Bear Island, has allowed for an identification of the factors that control spring bloom development in the region, and their interannual variability. In the southern part of the section the bloom starts as the waters become stratified due to a northward spreading of low salinity water from the Norwegian Coastal Current. In the middle part of the section the bloom is initiated when vernal stratification develops due to heating of the ocean surface, and the bloom may develop in either of two directions throughout summer, depending on the prevailing atmospheric pressure gradient over the region. A north to south high to low pressure gradient will direct surface winds to the west. Ekman drift will then be to the north and a wedge of low salinity, low nutrient water will spread out over the region, leading to the termination of the bloom. When the pressure gradient is reversed, winds will blow to the east and intrusion of fresh water into the region will be limited. In these years the bloom appears to follow a classical Atlantic pattern, unable to fully utilize available nitrate and probably terminated due to extensive grazing. The central part of the Barents Sea Opening is thus yet another northern high latitude region where the bloom is subject to substantial interannual variations, potentially affecting higher trophic levels.
Journal of Plankton Research, 1997
... Thomas T.Noji, Ulrich V.Bathmann1, Bodo von Bodungen2, Maren Voss2, Avan Antia3, Marita Krumb... more ... Thomas T.Noji, Ulrich V.Bathmann1, Bodo von Bodungen2, Maren Voss2, Avan Antia3, Marita Krumbholz3, Bert Klein4, Ilka Peeken3, Carola I.-M.Noji5 and ... tow in the upper 50 m on the coast of Norway; this is equivalent to abundances on the order of thou-sands of individuals ...
ICES Journal of Marine Science, 2007
Phytoplankton represents the primary trophic level in marine pelagic ecosystems, through which mo... more Phytoplankton represents the primary trophic level in marine pelagic ecosystems, through which most biological material produced by photosynthesis is further channelled through the foodweb via grazing by zooplankton. Therefore, the level and variability of primary production is believed to be an important factor for fish recruitment and growth. The Nordic seas are important feeding areas for large and important commercial fish stocks, but because of a scarcity of measurements, only few estimates of primary production exist. Additionally, primary production is highly variable because of the wide variations in light, temperature, and nutrient supply at a specific time and location. Here, primary production in the Nordic seas is studied using a coupled 3D physical, chemical, and biological ocean model, revealing large variations in primary production in space and time. The model gives a mean annual production of 73 gC m 22 y 21 and a 20% variation in phytoplankton biomass between the years of highest and lowest production. The interannual variability is linked to the North Atlantic Oscillation, sea ice, and the transport of water into the Nordic seas. The strong control of phytoplankton production by the physics suggests a possible mechanism for how climate can be an important driver for the availability of biological material in foodwebs.
ICES Journal of Marine Science, 2004
Hydrographic, oxygen and nutrient data collected in the Nordic Seas during the 1990s are presente... more Hydrographic, oxygen and nutrient data collected in the Nordic Seas during the 1990s are presented. During the decade, deep waters originating from the Arctic Ocean, identified by salinities in excess of 34.9, spread into the Greenland Basin. In 1991, these waters extended westward from the mid-ocean ridge to about 2(E. This process continued over time and by 1993 there was
Deep Sea Research Part II: Topical Studies in Oceanography, 1999
Sedimentation of particulate carbon from the upper 200}300 m in the central Greenland Sea from Au... more Sedimentation of particulate carbon from the upper 200}300 m in the central Greenland Sea from August 1993 to June 1995 was less than 2 g C m\ yr\. Daily rates of sedimentation of particulate organic carbon reached highest values of about 18 mg m\ d\ in fall 1994. For total particulate material, maximum rates of sedimentation of about 250 mg m\ d\ were recorded in spring and fall 1994. For chlorophyll equivalent, highest rates of sedimentation of about 140 g m\ d\ were recorded in spring 1994. As reported in related investigations, the transient accumulation of DOC in surface waters during summer, as well as respiration and mortality of deep overwintering zooplankton stocks, appeared to dominate the fate of photosynthetically "xed organic carbon. The above processes may account for roughly 43 g C m\ in the upper 200 m of the central Greenland Sea. For comparison, the seasonal de"cit in dissolved inorganic carbon was reported to be about 23 g C m\ in the upper 20 m of surface water, and estimates for new annual production were reported to be about 57 g C m\. In our investigation, the biological carbon pump was not unusually e!ective in transporting carbon out of the productive surface layer.
Deep Sea Research Part II: Topical Studies in Oceanography, 1999
During the 1993}1995 period of minimal deep convection in the Greenland Sea, the dissolved inorga... more During the 1993}1995 period of minimal deep convection in the Greenland Sea, the dissolved inorganic carbon concentration within the surface waters varied dramatically on the seasonal time scale, with average summer and winter values of 2064 ($10) and 2150 ($5) mol kg\, respectively, indicative of a vigorous annual carbon cycle. In contrast, there was very little interannual variability throughout these three years. While primary production largely depleted the surface nutrient supplies in spring and summer, generating a strong seasonal CO drawdown, a combination of relatively shallow remineralization and mixed-layer deepening brought essentially all of the carbon consumed by photosynthesis back into contact with the atmosphere before winter. This re-release of the inorganic carbon that had been consumed by phytoplankton earlier in the year was more than su$cient to counteract the cooling-induced increase in the carbon carrying capacity of the water during fall and winter, reducing the potential for atmospheric carbon dioxide absorption by the Greenland Sea over the same period.
ICES Journal of Marine Science, 1994
ICES Journal of Marine Science, 2012
Since 1990, a decline in silicate concentrations together with increasing salinities has been obs... more Since 1990, a decline in silicate concentrations together with increasing salinities has been observed in the Atlantic water of the Norwegian and Barents Seas. This decline in silicate has been found to be related to the relative proportion in which eastern and western source water masses from the northeastern North Atlantic enter the Norwegian Sea.
Journal of General Microbiology, 1979
Glucose repressed the synthesis of 1,3-/?-glucanase in Neurospora crassa. The production of enzym... more Glucose repressed the synthesis of 1,3-/?-glucanase in Neurospora crassa. The production of enzyme during growth in glucose-supplemented medium was negligible, but if deprived of carbon source the fungus actively synthesized high levels of enzyme when growth ceased. Similar results were obtained for 1,6-P-glucanase but less enzyme was produced. A different pattern of production of these enzymes was found in Trichoderma viride and Saccharomyces cerevisiae. The enzymes were produced in glucose-supplemented medium with increasing specific activity during growth. Resting cells deprived of glucose either failed to produce /?-glucanases or produced them in smaller quantities.
Marine Chemistry, Mar 1, 2001
Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gi... more Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gimsøy-NW section from 67.58N 98E to 71.58N 18E and the Bjørnøya-W section along 74.58N from 7 to 158E, are used to estimate oxygen fluxes in the surface layer and between the atmosphere and the ocean. Vertical entrainment velocities of 0.9 m day y1 for the winter season and 0.1 m day y1 for the summer season are found and applied to the upper 300 m. The resulting oxygen fluxes to the surface layer driven by this vertical mixing are 0.58 " 0.05 and 0.27 " 0.02 mol O m y2 year y1 at the Gimsøy-NW and 2 Bjørnøya-W sections, respectively. Oxygen fluxes to the surface layer due to phytoplankton production are 2.6 and 3.4 mol O m y2 year y1 , which represent the net community production at the two sections. Estimated uncertainties in these 2 numbers are "15%. The surface water is a sink for atmospheric oxygen during fall and winter and a source during the productive season for both sections. On an annual basis there is a net uptake of oxygen from the atmosphere, 3.4 " 0.4 mol O m y2 year y1 at the Gimsøy-NW section and 4.9 " 0.5 mol O m y2 year y1 at the Bjørnøya-W. A decrease in 2 2 temperature of 18C to 1.58C seen between the Gimsøy-NW section and the Bjørnøya-W section is the main reason for the increased atmospheric flux of oxygen at the latter section. An oxygen budget made for the area bounded by the two sections gives a net advective flux of oxygen out of the area of approximately 10 mol O m y2 year y1 . The increased concentration 2 of oxygen corresponding to the decrease in surface layer temperatures going northwards in the Norwegian Atlantic Current is mainly attributed to the air-sea oxygen exchange and phytoplankton production in this area. q
Earth System Science Data, 2009
... Earth Syst. Sci. Data, 1, 2534, 2009 www.earth-syst-sci-data.net/1/25/2009/ Page 3. A. Olsen... more ... Earth Syst. Sci. Data, 1, 2534, 2009 www.earth-syst-sci-data.net/1/25/2009/ Page 3. A. Olsen et al.: Overview of the Nordic Seas CARINA data and salinity measurements 27 45 o W 30 oW 15oW 0o 15 o E 30 o E 60 o N 65 o N 70 o N 75 o N 80 o N 85 o N ...
Geophysical Monograph Series, 2000
Studies of the inorganic carbon cycle have been performed in the Nordic Seas and the Barents Sea ... more Studies of the inorganic carbon cycle have been performed in the Nordic Seas and the Barents Sea since the 1980's. Here we present a review over current knowledge on carbon transport between the different reservoirs in the area, and the transformation of inorganic carbon to organic matter. The carbon transport and transformation are closely related to other biogeochemical processes in
The Northern North Atlantic, 2001
Tellus B, 2000
... to 1997. f CO 2 record used for the different years is the annual record of 1992 at weather s... more ... to 1997. f CO 2 record used for the different years is the annual record of 1992 at weather station ''Mike'' (Conway et al., 1994) plus 1.6 matm per year in 5. Airsea exchange ... approach is negligible in relation to the Df CO 2 , speed, plus some parameters related to the proper-...
Polar Research, 1991
An analysis is made of the photosynthesis-irradiance relationships in natural phytoplankton popul... more An analysis is made of the photosynthesis-irradiance relationships in natural phytoplankton populations in the Barents Sea. The data set comprises 232 experiments carried out during a 10-year period, both in open and ice-covered waters. The variability on the P-1 parameters is discussed and examined in relation to the variation in a variety of environmental conditions. The results suggest that in the Barents Sea. as in other Arctic areas, phytoplankton photosynthesis is mainly controlled by physical variables. However, control of the phytoplankton stock. i.e. by zooplankton grazing, seems also to have a considerable indirect influence on P-I parameters, especially after the spring bloom and the depletion of winter nutrients.
The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea ... more The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea since the late 1990s are examined using remote sensing data, observations and a coupled physical-biological model. Field observations of mesozooplankton biomass, and chlorophyll a data from transects (different seasons) and large-scale surveys (autumn) were used for validation of the remote sensing products and modeling results. The validation showed that satellite data are well suited to study temporal and spatial dynamics of chlorophyll a in the Barents Sea and that the model is an essential tool for secondary production estimates. Temperature, open water area, chlorophyll a, and zooplankton biomass show large interannual variations in the Barents Sea. The climatic variability is strongest in the northern and eastern parts. The moderate increase in net primary production evident in this study is likely an ecosystem response to changes in climate during the same period. Increased open water area and duration of open water season, which are related to elevated temperatures, appear to be the key drivers of the changes in annual net primary production that has occurred in the northern and eastern areas of this ecosystem. The temporal and spatial variability in zooplankton biomass appears to be controlled largely by predation pressure. In the southeastern Barents Sea, statistically significant linkages were observed between chlorophyll a and zooplankton biomass, as well as between net primary production and fish biomass, indicating bottom-up trophic interactions in this region.
Marine Chemistry, 2007
The seasonal and interannual variability of the air–sea CO2 flux (F) in the Atlantic sector of th... more The seasonal and interannual variability of the air–sea CO2 flux (F) in the Atlantic sector of the Barents Sea have been investigated. Data for seawater fugacity of CO2 (fCO2sw) acquired during five cruises in the region were used to identify and validate an empirical procedure to compute fCO2sw from phosphate (PO4), seawater temperature (T), and salinity (S). This procedure was
Marine Chemistry, 2001
Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gi... more Oxygen and phosphate measurements from two sections across the Norwegian Atlantic Current, the Gimsøy-NW section from 67.58N 98E to 71.58N 18E and the Bjørnøya-W section along 74.58N from 7 to 158E, are used to estimate oxygen fluxes in the surface layer and between the atmosphere and the ocean. Vertical entrainment velocities of 0.9 m day y1 for the winter season and 0.1 m day y1 for the summer season are found and applied to the upper 300 m. The resulting oxygen fluxes to the surface layer driven by this vertical mixing are 0.58 " 0.05 and 0.27 " 0.02 mol O m y2 year y1 at the Gimsøy-NW and 2 Bjørnøya-W sections, respectively. Oxygen fluxes to the surface layer due to phytoplankton production are 2.6 and 3.4 mol O m y2 year y1 , which represent the net community production at the two sections. Estimated uncertainties in these 2 numbers are "15%. The surface water is a sink for atmospheric oxygen during fall and winter and a source during the productive season for both sections. On an annual basis there is a net uptake of oxygen from the atmosphere, 3.4 " 0.4 mol O m y2 year y1 at the Gimsøy-NW section and 4.9 " 0.5 mol O m y2 year y1 at the Bjørnøya-W. A decrease in 2 2 temperature of 18C to 1.58C seen between the Gimsøy-NW section and the Bjørnøya-W section is the main reason for the increased atmospheric flux of oxygen at the latter section. An oxygen budget made for the area bounded by the two sections gives a net advective flux of oxygen out of the area of approximately 10 mol O m y2 year y1 . The increased concentration 2 of oxygen corresponding to the decrease in surface layer temperatures going northwards in the Norwegian Atlantic Current is mainly attributed to the air-sea oxygen exchange and phytoplankton production in this area. q
Sarsia: North Atlantic Marine Science, 2003
ABSTRACT Analysis of data obtained by the Institute of Marine Research, Norway, at their regular ... more ABSTRACT Analysis of data obtained by the Institute of Marine Research, Norway, at their regular surveys of the Fugløya-Bjørnøya section, between the northern tip of Norway and Bear Island, has allowed for an identification of the factors that control spring bloom development in the region, and their interannual variability. In the southern part of the section the bloom starts as the waters become stratified due to a northward spreading of low salinity water from the Norwegian Coastal Current. In the middle part of the section the bloom is initiated when vernal stratification develops due to heating of the ocean surface, and the bloom may develop in either of two directions throughout summer, depending on the prevailing atmospheric pressure gradient over the region. A north to south high to low pressure gradient will direct surface winds to the west. Ekman drift will then be to the north and a wedge of low salinity, low nutrient water will spread out over the region, leading to the termination of the bloom. When the pressure gradient is reversed, winds will blow to the east and intrusion of fresh water into the region will be limited. In these years the bloom appears to follow a classical Atlantic pattern, unable to fully utilize available nitrate and probably terminated due to extensive grazing. The central part of the Barents Sea Opening is thus yet another northern high latitude region where the bloom is subject to substantial interannual variations, potentially affecting higher trophic levels.
Journal of Plankton Research, 1997
... Thomas T.Noji, Ulrich V.Bathmann1, Bodo von Bodungen2, Maren Voss2, Avan Antia3, Marita Krumb... more ... Thomas T.Noji, Ulrich V.Bathmann1, Bodo von Bodungen2, Maren Voss2, Avan Antia3, Marita Krumbholz3, Bert Klein4, Ilka Peeken3, Carola I.-M.Noji5 and ... tow in the upper 50 m on the coast of Norway; this is equivalent to abundances on the order of thou-sands of individuals ...
ICES Journal of Marine Science, 2007
Phytoplankton represents the primary trophic level in marine pelagic ecosystems, through which mo... more Phytoplankton represents the primary trophic level in marine pelagic ecosystems, through which most biological material produced by photosynthesis is further channelled through the foodweb via grazing by zooplankton. Therefore, the level and variability of primary production is believed to be an important factor for fish recruitment and growth. The Nordic seas are important feeding areas for large and important commercial fish stocks, but because of a scarcity of measurements, only few estimates of primary production exist. Additionally, primary production is highly variable because of the wide variations in light, temperature, and nutrient supply at a specific time and location. Here, primary production in the Nordic seas is studied using a coupled 3D physical, chemical, and biological ocean model, revealing large variations in primary production in space and time. The model gives a mean annual production of 73 gC m 22 y 21 and a 20% variation in phytoplankton biomass between the years of highest and lowest production. The interannual variability is linked to the North Atlantic Oscillation, sea ice, and the transport of water into the Nordic seas. The strong control of phytoplankton production by the physics suggests a possible mechanism for how climate can be an important driver for the availability of biological material in foodwebs.
ICES Journal of Marine Science, 2004
Hydrographic, oxygen and nutrient data collected in the Nordic Seas during the 1990s are presente... more Hydrographic, oxygen and nutrient data collected in the Nordic Seas during the 1990s are presented. During the decade, deep waters originating from the Arctic Ocean, identified by salinities in excess of 34.9, spread into the Greenland Basin. In 1991, these waters extended westward from the mid-ocean ridge to about 2(E. This process continued over time and by 1993 there was
Deep Sea Research Part II: Topical Studies in Oceanography, 1999
Sedimentation of particulate carbon from the upper 200}300 m in the central Greenland Sea from Au... more Sedimentation of particulate carbon from the upper 200}300 m in the central Greenland Sea from August 1993 to June 1995 was less than 2 g C m\ yr\. Daily rates of sedimentation of particulate organic carbon reached highest values of about 18 mg m\ d\ in fall 1994. For total particulate material, maximum rates of sedimentation of about 250 mg m\ d\ were recorded in spring and fall 1994. For chlorophyll equivalent, highest rates of sedimentation of about 140 g m\ d\ were recorded in spring 1994. As reported in related investigations, the transient accumulation of DOC in surface waters during summer, as well as respiration and mortality of deep overwintering zooplankton stocks, appeared to dominate the fate of photosynthetically "xed organic carbon. The above processes may account for roughly 43 g C m\ in the upper 200 m of the central Greenland Sea. For comparison, the seasonal de"cit in dissolved inorganic carbon was reported to be about 23 g C m\ in the upper 20 m of surface water, and estimates for new annual production were reported to be about 57 g C m\. In our investigation, the biological carbon pump was not unusually e!ective in transporting carbon out of the productive surface layer.
Deep Sea Research Part II: Topical Studies in Oceanography, 1999
During the 1993}1995 period of minimal deep convection in the Greenland Sea, the dissolved inorga... more During the 1993}1995 period of minimal deep convection in the Greenland Sea, the dissolved inorganic carbon concentration within the surface waters varied dramatically on the seasonal time scale, with average summer and winter values of 2064 ($10) and 2150 ($5) mol kg\, respectively, indicative of a vigorous annual carbon cycle. In contrast, there was very little interannual variability throughout these three years. While primary production largely depleted the surface nutrient supplies in spring and summer, generating a strong seasonal CO drawdown, a combination of relatively shallow remineralization and mixed-layer deepening brought essentially all of the carbon consumed by photosynthesis back into contact with the atmosphere before winter. This re-release of the inorganic carbon that had been consumed by phytoplankton earlier in the year was more than su$cient to counteract the cooling-induced increase in the carbon carrying capacity of the water during fall and winter, reducing the potential for atmospheric carbon dioxide absorption by the Greenland Sea over the same period.