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Diurnal vertical migration (DVM) is a widespread phenomenon in the upper ocean, but it remains unclear to what degree it also involves passively transported micro- and meso-zooplankton. These organisms are difficult to monitor by in situ sensing and observations from discrete samples are often inconclusive. Prime examples of such ambiguity are planktonic foraminifera, where contradictory evidence for DVM continues to cast doubt on the stability of species vertical habitats, which introduces uncertainties in geochemical proxy interpretation. To provide a robust answer, we carried out highly replicated randomized sampling with 41 vertically resolved plankton net hauls taken within 26 hours in a confined area of 400 km2 in the tropical North Atlantic, where DVM in larger plankton occurs. Manual enumeration of planktonic foraminifera cell density consistently reveals the highest total cell concentrations in the surface mixed layer (top 50 m) and analysis of cell density in seven individual species representing different shell sizes, life strategies and presumed depth habitats reveals consistent vertical habitats not changing over the 26 hours sampling period. These observations robustly reject the existence of DVM in planktonic foraminifera in a setting where DVM occurs in other organisms.

Diurnal vertical migration (DVM) is a widespread phenomenon in the upper ocean, but it remains unclear to what degree it also involves passively transported micro- and meso-zooplankton. These organisms are difficult to monitor by in situ sensing and observations from discrete samples are often inconclusive. Prime examples of such ambiguity are planktonic foraminifera, where contradictory evidence for DVM continues to cast doubt on the stability of species vertical habitats, which introduces uncertainties in geochemical proxy interpretation. To provide a robust answer, we carried out highly replicated randomized sampling with 41 vertically resolved plankton net hauls taken within 26 hours in a confined area of 400 km2 in the tropical North Atlantic, where DVM in larger plankton occurs. Manual enumeration of planktonic foraminifera cell density consistently reveals the highest total cell concentrations in the surface mixed layer (top 50 m) and analysis of cell density in seven individual species representing different shell sizes, life strategies and presumed depth habitats reveals consistent vertical habitats not changing over the 26 hours sampling period. These observations robustly reject the existence of DVM in planktonic foraminifera in a setting where DVM occurs in other organisms.

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.

R/V METEOR expedition M125 (“SAMBA”) focused on the influence of paleoceanographic changes off NE Brazil on the continental hydrological cycle. For this purpose, we obtained 202 m of gravity (24 stations) and piston cores (9) at seven sections on the shelf and continental slope close to river mouths from Cabo Frio in the south to the Rio Sao Francisco in the north. Coring stations were determined after intensive echosounder surveys (total: 1221 NM). On-board foraminiferal biostratigraphy, as well as color and XRF-scanning already provided first stratigraphic constraints, indicating the preservation of different regional paleoclimatic signals at the respective sections. Based on the preliminary stratigraphy, we retrieved high-resolution archives, covering Holocene sediments on the shelf and late Pleistocene sediments on the slope. These high-resolution archives are complemented by long-term records covering up to 900 ka of continuous sedimentation at deeper sites at smaller rivers. For proxy-calibration and the study of present-day sedimentation dynamics and biogeochemical processes, surface sediments were sampled via multicorer (47), Van Veen Grab (6) and box corer (3). Water samples for determination of the water chemistry (trace elements, stable and radiogenic isotopes) and nutrient composition were retrieved by 55 CTD/Rosette casts. In addition, we run multinet-hauls at seven stations to investigate the planktonic foraminiferal communities in the water column down to 700 m water depth, complemented by filtering water from the ship’s pump twice a day.

R/V METEOR expedition M125 (“SAMBA”) focused on the influence of paleoceanographic changes off NE Brazil on the continental hydrological cycle. For this purpose, we obtained 202 m of gravity (24 stations) and piston cores (9) at seven sections on the shelf and continental slope close to river mouths from Cabo Frio in the south to the Rio Sao Francisco in the north. Coring stations were determined after intensive echosounder surveys (total: 1221 NM). On-board foraminiferal biostratigraphy, as well as color and XRF-scanning already provided first stratigraphic constraints, indicating the preservation of different regional paleoclimatic signals at the respective sections. Based on the preliminary stratigraphy, we retrieved high-resolution archives, covering Holocene sediments on the shelf and late Pleistocene sediments on the slope. These high-resolution archives are complemented by long-term records covering up to 900 ka of continuous sedimentation at deeper sites at smaller rivers. For proxy-calibration and the study of present-day sedimentation dynamics and biogeochemical processes, surface sediments were sampled via multicorer (47), Van Veen Grab (6) and box corer (3). Water samples for determination of the water chemistry (trace elements, stable and radiogenic isotopes) and nutrient composition were retrieved by 55 CTD/Rosette casts. In addition, we run multinet-hauls at seven stations to investigate the planktonic foraminiferal communities in the water column down to 700 m water depth, complemented by filtering water from the ship’s pump twice a day.

R/V METEOR expedition M125 (“SAMBA”) focused on the influence of paleoceanographic changes off NE Brazil on the continental hydrological cycle. For this purpose, we obtained 202 m of gravity (24 stations) and piston cores (9) at seven sections on the shelf and continental slope close to river mouths from Cabo Frio in the south to the Rio Sao Francisco in the north. Coring stations were determined after intensive echosounder surveys (total: 1221 NM). On-board foraminiferal biostratigraphy, as well as color and XRF-scanning already provided first stratigraphic constraints, indicating the preservation of different regional paleoclimatic signals at the respective sections. Based on the preliminary stratigraphy, we retrieved high-resolution archives, covering Holocene sediments on the shelf and late Pleistocene sediments on the slope. These high-resolution archives are complemented by long-term records covering up to 900 ka of continuous sedimentation at deeper sites at smaller rivers. For proxy-calibration and the study of present-day sedimentation dynamics and biogeochemical processes, surface sediments were sampled via multicorer (47), Van Veen Grab (6) and box corer (3). Water samples for determination of the water chemistry (trace elements, stable and radiogenic isotopes) and nutrient composition were retrieved by 55 CTD/Rosette casts. In addition, we run multinet-hauls at seven stations to investigate the planktonic foraminiferal communities in the water column down to 700 m water depth, complemented by filtering water from the ship’s pump twice a day.

R/V METEOR expedition M125 (“SAMBA”) focused on the influence of paleoceanographic changes off NE Brazil on the continental hydrological cycle. For this purpose, we obtained 202 m of gravity (24 stations) and piston cores (9) at seven sections on the shelf and continental slope close to river mouths from Cabo Frio in the south to the Rio Sao Francisco in the north. Coring stations were determined after intensive echosounder surveys (total: 1221 NM). On-board foraminiferal biostratigraphy, as well as color and XRF-scanning already provided first stratigraphic constraints, indicating the preservation of different regional paleoclimatic signals at the respective sections. Based on the preliminary stratigraphy, we retrieved high-resolution archives, covering Holocene sediments on the shelf and late Pleistocene sediments on the slope. These high-resolution archives are complemented by long-term records covering up to 900 ka of continuous sedimentation at deeper sites at smaller rivers. For proxy-calibration and the study of present-day sedimentation dynamics and biogeochemical processes, surface sediments were sampled via multicorer (47), Van Veen Grab (6) and box corer (3). Water samples for determination of the water chemistry (trace elements, stable and radiogenic isotopes) and nutrient composition were retrieved by 55 CTD/Rosette casts. In addition, we run multinet-hauls at seven stations to investigate the planktonic foraminiferal communities in the water column down to 700 m water depth, complemented by filtering water from the ship’s pump twice a day.

Final Report fo r Peri od October 1986 -October 1987, Impulsively-started uniform flow, decelerating at specified rates, about two-dimensional cambered plates with included angles of 120, 180, and 240 degrees has been investigated both theoretically and experimentally. The experiments were conducted in a vertical water tunnel. The forces acting on the cambered plates have been determined as a function of relative displacement of the fluid. The evolution of the vortices was visualized by means of various dyes and polystyrene beads. A numerical analysis was carried out through the use of the discrete vortex model. Vorticity is represented by a distribution of discrete line vortices. Each vortex is convected in the velocity field according to the Biot-Savart law. The rollup of the vortex sheets, the distribution of velocity and pressure on the cambers, and the drag and lift forces are calculated at suitable time intervals for a prescribed time-dependent flow. The results are compared with those obtained experimentally., The work reported herein was supported by the Sandia National Laboratories with funds provided by the United States Department of Energy., Approved for public release; distribution is unlimited.

The CAT Imaging Telescope has observed the BL Lac object Markarian 501 between March and August 1997. We report here on the variability over this time including several large flares. We present also preliminary spectra for all these data, for the low emission state, and for the largest flare., Comment: 4 pages, 4 figures, Latex

The CAT imaging telesope, which uses the Atmospheric Cherenkov Technique to observe TeV gamma-ray sources, has been operating since September 1996. Located in southern France, it features a fine grained camera consisting of 546 PMT with a pixel size of 0.12 degrees. Strong gamma-ray signals from Mkn 501 above 200 GeV were detected during observations made in April 1997. The high signal/noise ratio for these data enables direct characterization of the gamma-ray images as recorded in the camera. These results are used to validate the Monte-Carlo simulations of the response of the telescope to gamma-ray showers and to improve its performances. Observational results on Mkn 180 and the Crab nebula spectrum are presented., Comment: 6 pages, 3 figures, Latex

The CAT imaging telesope, which uses the Atmospheric Cherenkov Technique to observe TeV gamma-ray sources, has been operating since September 1996. Located in southern France, it features a fine grained camera consisting of 546 PMT with a pixel size of 0.12 degrees. Strong gamma-ray signals from Mkn 501 above 200 GeV were detected during observations made in April 1997. The high signal/noise ratio for these data enables direct characterization of the gamma-ray images as recorded in the camera. These results are used to validate the Monte-Carlo simulations of the response of the telescope to gamma-ray showers and to improve its performances. Observational results on Mkn 180 and the Crab nebula spectrum are presented., Comment: 6 pages, 3 figures, Latex

The CAT Imaging Telescope has observed the BL Lac object Markarian 501 between March and August 1997. We report here on the variability over this time including several large flares. We present also preliminary spectra for all these data, for the low emission state, and for the largest flare., Comment: 4 pages, 4 figures, Latex

Impulsively-started uniform flow, decelerating at specified rates, about two-dimensional cambered plates with included angles of 120, 180, and 240 degrees has been investigated both theoretically and experimentally. The experiments were conducted in a vertical water tunnel. The forces acting on the cambered plates have determined as a function of the relative displacement of the fluid. The evolution of the vortices was visualized by means of various dyes and polystyrene beads. A numerical analysis was carried out through the use of the discrete vortex model. Vorticity is represented by a distribution of discrete line vortices. Each vortex is convected in the velocity field according to the Biot Savart law. The rollup of the vortex sheets, the distribution of velocity and pressure on the chambers, and the drag and lift forces are calculated at suitable time intervals for a prescribed time-dependent flow. The results are compared with those obtained experimentally. Keywords: Unsteady flow, Discrete vortex model, Cambered plate, Parachute, Experiments, Analysis.

Impulsively-started uniform flow, decelerating at specified rates, about two-dimensional cambered plates with included angles of 120, 180, and 240 degrees has been investigated both theoretically and experimentally. The experiments were conducted in a vertical water tunnel. The forces acting on the cambered plates have been determined as a function of relative displacement of the fluid. The evolution of the vortices was visualized by means of various dyes and polystyrene beads. A numerical analysis was carried out through the use of the discrete vortex model. Vorticity is represented by a distribution of discrete line vortices. Each vortex is convected in the velocity field according to the Biot-Savart law. The rollup of the vortex sheets, the distribution of velocity and pressure on the cambers, and the drag and lift forces are calculated at suitable time intervals for a prescribed time-dependent flow. The results are compared with those obtained experimentally.

We present an updated time frame for the 30 m thick late Miocene sedimentary Trachilos section from the island of Crete that contains the potentially oldest hominin footprints. The section is characterized by normal magnetic polarity. New and published foraminifera biostratigraphy results suggest an age of the section within the Mediterranean biozone MMi13d, younger than ~ 6.4 Ma. Calcareous nannoplankton data from sediments exposed near Trachilos and belonging to the same sub-basin indicate deposition during calcareous nannofossil biozone CN9bB, between 6.023 and 6.727 Ma. By integrating the magneto- and biostratigraphic data we correlate the Trachilos section with normal polarity Chron C3An.1n, between 6.272 and 6.023 Ma. Using cyclostratigraphic data based on magnetic susceptibility, we constrain the Trachilos footprints age at ~ 6.05 Ma, roughly 0.35 Ma older than previously thought. Some uncertainty remains related to an inaccessible interval of ~ 8 m section and the possibility that the normal polarity might represent the slightly older Chron C3An.2n. Sediment accumulation rate and biostratigraphic arguments, however, stand against these points and favor a deposition during Chron C3An.1n.