DOI: 10.20350/digitalcsic/6218
title: Nested scales of pH variability in sub-Arctic Kobbefjord, SW Greenland

description: Content and values displayed: The data is displayed in an excel file with spreadsheets representing each of the following spatial scales: -“Fjord-scale”: The data set includes information on measurements representing vertical profiles at sites distributed along a horizontal fjord gradient: Date, site (station), water depth, temperature, pH, Ωarag, oxygen concentration (O2) and fluorescence -“Small-scale/kelp-scale”: The data set includes information from 3 consecutive series of parallel deployments over 2-3 days in shallow subtidal kelp habitats (kelp) and neighboring habitats colonized by benthic microalgae and scattered filamentous algae (bare) in Kobbefjord. We provide information on date and time, deployment number (#1-3), and each of the following variables measured ca 50 cm above the seafloor in the two types of habitat (kelp and bare): temperature, pH, salinity, water depth, O2, PAR and Ωarag. In addition, we provide information on pH-variability within 1m3 of kelp forest measured by an array of 16 pH-sensors placed in 4 layers of the kelp forest: 10 cm above the seafloor, 20 cm above the seafloor, in the canopy and in the water column just above the canopy. -“Micro-scale”: The data set includes information on pH at a millimeter scale measured through the boundary layer of 6 different species of macrophytes (Ascophyllum nodosum, Fucus vesiculosus, Saccharina longicruris, Agarum clathratum, Ulva lactuca, Zostera marina) by microelectrode in a laboratory setup. For each point we provide the average and standard deviation (SD) of 3 replicate measurements of each species. -“Tidal pools”: The date set represents parallel diurnal measurements in a vegetated tidal pool and the adjacent vegetated shore in the inner part of Kobbefjord. For each site and sampling time we provide data on O2, salinity, temperature, pH, total alkalinity (AT), total inorganic carbon (CT), partial pressure of CO2 (pCO2)and Ωarag in the water.
description: Access and reuse: The database is subject to a Creative Commons Attribution-Noncommercial-ShareAlike International licence 4.0. Contact person for enquiries: Dorte Krause-Jensen, dkj@bios.au.dk.
description: This dataset represents spatiotemporal variability in coastal pH-variability measured in a nested scale in the sub-Arctic Kobbefjord (64⁰10’ N, 51⁰33’ W) which makes part of the extensive Godthåbsfjordsystem near Nuuk, SW Greenland. A sensor array logging pH, oxygen, photosynthetically active radiation (PAR), temperature and salinity was applied on spatial scales ranging from km-scale across the horizontal extension of the fjord, over 100 m-scale vertically in the fjord, 10-100 m scale between subtidal habitats with and without kelp forests and between vegetated tidal pools and adjacent vegetated shores, to cm-m scale within kelp forests and pH was also measured at mm-scale across boundary layers of macrophyte tissue. In addition, we assessed the temporal variability in pH on diurnal and seasonal scales. Based on pH-measurements combined with relationships between salinity, total alkalinity and dissolved inorganic carbon we also estimated variability of the carbonate saturation state for aragonite Ωarag. Fjord-scale data sets were collected during three field campaigns (19 Apr, 18 Jul, 3 Sep 2013), shallow subtidal habitats and microscale data sets represent an intensive campaign (27 August–6 September 2013) and intertidal data were collected ultimo Aug 2014. Methods are described in detail in Krause-Jensen et al. (2015) which also contains a thorough presentation, analysis and discussion of the results.