Radiocarbon dating on cold-water corals, grain size, Corg, and benthic foraminfera assemblage of two sediment cores from the Ionian Sea

Continuous sedimentary records from an eastern Mediterranean cold-water coral ecosystem thriving in intermediate water depths (~600 m) reveal a temporary extinction of cold-water corals during the Early to Mid Holocene from 11.4-5.9 cal kyr BP. Benthic foraminiferal assemblage analysis shows low-oxygen conditions of 2 ml l**-1 during the same period, compared to bottom-water oxygen values of 4-5 ml l**-1 before and after the coral-free interval. The timing of the corals' demise coincides with the sapropel S1 event, during which the deep eastern Mediterranean basin turned anoxic. Our results show that during the sapropel S1 event low oxygen conditions extended to the rather shallow depths of our study site in the Ionian Sea and caused the cold-water corals temporary extinction. This first evidence for the sensitivity of cold-water corals to low oceanic oxygen contents suggests that the projected expansion of tropical oxygen minimum zones resulting from global change will threaten cold-water coral ecosystems in low latitudes in the same way that ocean acidification will do in the higher latitudes.

Zooplankton abundance and size structure in the North Atlantic from M87/1_615-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Gridded bathymetry from multibeam echosounder HS-DS2 data of the cruise M51/4 (2001)

Bathymetry based on data recorded during M51-4 between 13.12.2001 and 28.12.2001 in the Black Sea. The purpose of the present-study was to sample sediments and the water columns of the nw/sw Black Sea and the E Marmara Sea to study a) a high resolution sediment records of Holocene climate, b) biogeochemical associated with deep anaerobic methane oxidation, and c) element cycling in the stratified water column. Bathymetric data (hydrosweep + parasound) was primarily used to choose appropriate sites for coring of undisturbed sediments. Samples were taken for future analyses of abundance and activity of bacteria, geochemistry and dating.

Zooplankton abundance and size structure in the North Atlantic from M87/1_701-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Zooplankton abundance and size structure in the North Atlantic from M87/1_530-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Zooplankton abundance and size structure in the North Atlantic from M87/1_699-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Zooplankton abundance and size structure in the North Atlantic from M87/1_518-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Zooplankton abundance and size structure in the North Atlantic from M87/1_593-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).

Zooplankton abundance and size structure in the North Atlantic from M87/1_633-1

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment during the development of the phytoplankton spring bloom at 4 stations in the North Atlantic. Station 1 in the Icelandic Basin was visited four times (26 March, 8 April, 18 April, 27 April), Station 2 in the southern Norwegian Sea was visited three times (30 March, 13 April, 23 April), Station 3 in the North Sea was visited twice (2 April, 15 April) and one intermediate station was visited once. The data were sampled by a Laser Optical Plankton Counter (LOPC, Rolls Royce Canada Ltd.) that was mounted on a carousel water sampler together with a Conductivity-Temperature-Depth sensor (CTD, SBE19plusV2, Seabird Electronics, Inc., USA). Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10 (body volume) increments (Edvardsen et al., 2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column (Herman et al., 2004; doi:10.1093/plankt/fbh095). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).