A 18-years long (1993-2011) snow and meteorological dataset from a mid-altitude mountain site (Col de Porte, France, 1325 altitude)

A quality-controlled snow and meteorological dataset spanning the period 1 August 1993-31 July 2011 is presented, originating from the experimental station Col de Porte (1325 m altitude, Chartreuse range, France). Emphasis is placed on meteorological data relevant to the observation and modelling of the seasonal snowpack. In-situ driving data, at the hourly resolution, consist of measurements of air temperature, relative humidity, windspeed, incoming short-wave and long-wave radiation, precipitation rate partitioned between snow- and rainfall, with a focus on the snow-dominated season. Meteorological data for the three summer months (generally from 10 June to 20 September), when the continuity of the field record is not warranted, are taken from a local meteorological reanalysis (SAFRAN), in order to provide a continuous and consistent gap-free record. Data relevant to snowpack properties are provided at the daily (snow depth, snow water equivalent, runoff and albedo) and hourly (snow depth, albedo, runoff, surface temperature, soil temperature) time resolution. Internal snowpack information is provided from weekly manual snowpit observations (mostly consisting in penetration resistance, snow type, snow temperature and density profiles) and from a hourly record of temperature and height of vertically free ''settling'' disks. This dataset has been partially used in the past to assist in developing snowpack models and is presented here comprehensively for the purpose of multi-year model performance assessment. The data is placed on the PANGAEA repository (doi:10.1594/PANGAEA.774249) as well as on the public ftp server ftp://ftp-cnrm.meteo.fr/pub-cencdp/.

The formation of a subsurface anticyclonic eddy in the Peru-Chile Undercurrent and its impact on the near-coastal salinity, oxygen and nutrient distributions

The formation of a subsurface anticyclonic eddy in the Peru-Chile Undercurrent (PCUC) in January and February 2013 is investigated using a multi-platform four-dimensional observational approach. Research vessel, multiple glider and mooring-based measurements were conducted in the Peruvian upwelling regime near 12°30'S. The dataset consists of more than 10000 glider profiles and repeated vessel-based hydrography and velocity transects. It allows a detailed description of the eddy formation and its impact on the near-coastal salinity, oxygen and nutrient distributions. In early January, a strong PCUC with maximum poleward velocities of ca. 0.25 m/s at 100 to 200 m depth was observed. Starting on January 20 a subsurface anticyclonic eddy developed in the PCUC downstream of a topographic bend, suggesting flow separation as the eddy formation mechanism. The eddy core waters exhibited oxygen concentrations less than 1mol/kg, an elevated nitrogen-deficit of ca. 17µmol/l and potential vorticity close to zero, which seemed to originate from the bottom boundary layer of the continental slope. The eddy-induced across-shelf velocities resulted in an elevated exchange of water masses between the upper continental slope and the open ocean. Small scale salinity and oxygen structures were formed by along-isopycnal stirring and indications of eddy-driven oxygen ventilation of the upper oxygen minimum zone were observed. It is concluded that mesoscale stirring of solutes and the offshore transport of eddy core properties could provide an important coastal open-ocean exchange mechanism with potentially large implications for nutrient budgets and biogeochemical cycling in the oxygen minimum zone off Peru.

Natural fluctuations and gradients in the experimental design:research bias in the field of ocean acidification

These data form the basis of an analysis of a prevalent research bias in the field of ocean acidification, notably the ignoring of natural fluctuations and gradients in the experimental design. The data are extracted from published work and own experiments.

The effects of thermal and high-CO2 stresses on the metabolism and surrounding microenvironment of the coral Galaxea fascicularis

The effects of elevated temperature and high pCO2 on the metabolism of Galaxea fascicularis were studied with oxygen and pH microsensors. Photosynthesis and respiration rates were evaluated from the oxygen fluxes from and to the coral polyps. High-temperature alone lowered both photosynthetic and respiration rates. High pCO2 alone did not significantly affect either photosynthesis or respiration rates. Under a combination of high-temperature and high-CO2, the photosynthetic rate increased to values close to those of the controls. The same pH in the diffusion boundary layer was observed under light in both (400 and 750 ppm) CO2 treatments, but decreased significantly in the dark as a result of increased CO2. The ATP contents decreased with increasing temperature. The effects of temperature on the metabolism of corals were stronger than the effects of increased CO2. The effects of acidification were minimal without combined temperature stress. However, acidification combined with higher temperature may affect coral metabolism due to the amplification of diel variations in the microenvironment surrounding the coral and the decrease in ATP contents.