ALBERT

Description: CAMELS-CL relies on multiple data sources (including ground data, remote-sensed products and reanalyses) to characterise the hydroclimatic conditions and landscape of a region where in situ measurements are scarce. The dataset includes 516 catchments and provides boundaries, daily streamflow records and basin-averaged daily time series of precipitation (from one national and three global datasets), maximum, minimum and mean temperatures, potential evapotranspiration (PET; from two datasets), and snow water equivalent. We calculated hydro-climatological indices using these time series, and leveraged diverse data sources to extract topographic, geological and land cover features. Relying on publicly available reservoirs and water rights data for the country, we estimated the degree of anthropic intervention within the catchments. To facilitate the use of this dataset and promote common standards in large-sample studies, we computed most catchment attributes introduced by Addor et al. (2017) in their Catchment Attributes and MEteorology for Large-sample Studies (CAMELS) dataset (doi:10.5065/D6G73C3Q), and added several others. --- CAMELS-CL can be visualised from http://camels.cr2.cl --- This research emerged from the collaboration with many colleagues at the Center for Climate and Resilience Research (CR2, CONICYT/FONDAP/15110009). Camila Alvarez-Garreton was funded by FONDECYT postdoctoral grant no. 3170428. Pablo Mendoza received additional support from FONDECYT postdoctoral grant no. 3170079. Mauricio Zambrano-Bigiarini thanks FONDECYT 11150861 for financial support. The development of CR2MET was supported by the Chilean Water Directorate (DGA), through National Water Balance Updating Project DGA-2319, and by FONDECYT grant no. 3150492. This study is a contribution to the Large-sample Hydrology working group of the Panta Rhei Research Initiative of the International Association of Hydrological Sciences (IAHS).

Description: The database includes measurements of the trace gases carbonyl sulfide (OCS) and carbon disulfide (CS2) in seawater (in picomol per liter) and the marine boundary layer (parts per trillion, ppt). It consists of individual datasets compiled from published original data, digitalization from publications (pdf documents) and unpublished data. Only shipborne measurements or measurements from time series stations with a dominant marine signal are included. The database contains mainly surface ocean measurements, but few available profiles down to 〉1000 m are included as well. Temporal resolution ranges from 12 minutes to hourly or monthly intervals. The database includes the following metadata (if available): latitude, longitude, depth, time of sampling, meteorological and physical parameters, main reference, method, contributor(s). The database is intended to facilitate model evaluation and the identification of global patterns. Data in excel and txt-files are identical.

Description: A quick new method is described for the quantification of absolute nannofossil proportions in deep-sea sediments. This method (SMS) is the combination of Spiking a sample with Microbeads and Spraying it on a cover slide. It is suitable for scanning electron microscope (SEM) analyses and for light microscope (LM) analyses. Repeated preparation and counting of the same sample (30 times) revealed a standard deviation of 10.5%. The application of tracer microbeads with different diameters and densities revealed no statistically significant differences between counts. The SMS-method yielded coccolith numbers that are statistically not significantly different from values obtained from the filtration-method. However, coccolith counts obtained by the random settling method are three times higher than the values obtained by the SMS- and the filtration-method.

Description: Precipitation that falls as snow at high elevations is one of the principal water sources for the downstream areas in the dry Andes of Central Chile. The last decade was especially dry, with most years showing below-normal annual precipitation - the so-called central Chile megadrought. Together with increased water consumption, the dry conditions have led to considerable water stress. People living in high mountain areas are especially vulnerable to this water scarcity, which raises their awareness and interest in meteorological observations. This dataset contains measurements of fresh snow and rain obtained in the citizen science project Vecinos de las Nieves (Spanish for “snow neighbors”) - a collaboration between scientists and community members who live, work or study in the mountainous sector (above 1100 m asl.) in the Andes mountains of the Coquimbo region, Chile (29°S to 32°S). Since 2018, following each snowfall during the austral Winter (May to August), the volunteers have measured the physical-chemical characteristics of the snow on the ground. Since 2021, the volunteers have also collected rainfall with a manual rain gauge. In total, 21 precipitation events have been documented, with a maximum snow depth of 292 mm at the highest observation site (3110 m asl.). In addition, 25 fresh snow samples from 9 snowfall events have been collected and successfully processed, to derivate stable hydrogen and oxygen isotopes, whose values are in line with the global meteoric line. The program Vecinos de las Nieves has generated new scientific understanding of snow and rain processes during the four winter periods, as well as connected isolated communities in the pursuit of science, and has highlighted the importance of local knowledge and interdisciplinary research in understanding snow dynamics and water availability in this area. Most participants have observed drier conditions in their environment during the last years, with fewer snow events compared to previous years, showing growing concern about the water availability in the future.

Description: Pigment concentration and pigment-based phytoplankton community composition data from a KOSMOS mesocosm experiment carried out in the frame work of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on the phytoplankton community. Filters were analysed for a range of photosynthetic pigments using reverse-phase high-performance liquid chromatography (HPLC). Based on pigment concentrations, phytoplankton community composition was approximated using the CHEMTAX software with the original pigment ratios from Mackey et al (1996, doi:10.3354/meps144265). The input included Chl a, b, c2, and c3, peridinin, 19'-butanoyloxyfucoxanthin, fucoxanthin, neoxanthin, prasinoxanthin, violaxanthin, 19'-hexanoyloxyfucoxanthin, alloxanthin, diadinoxanthin, diatoxanthin and zeaxanthin. Divinyl Chl a was instead fully associated with Prochlorophyceae. The presence of the main phytoplankton groups is expressed in Chl a equivalents.

Description: Size fractionated primary productivity rate measurements through 14C radioisotope incorporation rates from a KOSMOS mesocosm experiment carried out in the frame work of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on the phytoplankton community. Data shown includes production rates of dissolved organic carbon, particulate organic carbon in 3 size fractions (0.2-2 µm, 2-20 µm, 〉20 µm) and total organic carbon.

Description: Export data from the mesocosm experiment conducted in the Canary Islands in autumn 2019. Sinking matter was collected in 2-days intervals over the course of 33 days from the mesocosm sediment traps (4 m depth). Sediment samples were processed and subsampled for duplicate measurements of particulate organic carbon (POC), nitrogen (PON), phosphorus (POP) and biogenic silica (BSi). Elemental mass fluxes in µmol L-1 were calculated by normalizing to the mesocosm volume. They were then either normalized to the time between sample collection (48 h) to obtain daily mass fluxes (µmol L-1 d-1), or added up to obtain cumulative mass fluxes (µmol L-1). Another set of sediment subsamples was analyzed for particle sinking velocities, sizes and porosities (bidaily) and microbial remineralization rates (every 4 days).

Description: Oxygen production and respiration rates from a KOSMOS mesocosm experiment carried out in the framework of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on the phytoplankton community. Data shown includes gross and net community production as well as community respiration in µmol O2 per liter and hour/day. Measured through incubations and Winkler titrations.