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C Concentrations and Characterization Data from DOM Incubation Assay Experiments
This dataset includes (1) original data from a dissolved organic carbon (DOC) incubation experiment and (2) a data synthesis of the DOC incubation experiment literature. Study component (1) was a factorial lab experiment crossing varying dissolved organic matter (DOM) sources (Suwannee River Fulvic Acid, Elliott soil leachate, Chlorella leachate) with varying microbial communities. The objective of this study component was to test the interacting effects of microbial community composition and DOM characteristics on carbon (C) biodegradation. We used a Micro-Oxymax Respirometer (Columbus Instruments, Columbus, Ohio) to measure carbon dioxide and oxygen accumulation at two hour intervals for a period of two weeks, and quantified the initial and final concentrations of dissolved organic carbon and total dissolved nitrogen of each experimental unit. To verify that the three DOM source solutions had differing chemical compositions and potential bioreactivity, we optically characterized each DOM source using mass spectra analysis and excitation-emission matrices (EEMs). Study component (2) is a synthesis of DOC concentrations from the C degradation experiment literature. The criteria for including a study in this synthesis was that (a) incubation DOM was sourced from a river, lake, marine, estuary, or marsh, and (b) that C concentrations were measured at least twice throughout the incubation in addition to an initial measurement. For each study, we extracted initial DOC values, elapsed incubation time, and reported DOC concentrations during the incubation period for each experimental treatment. This data package is completed.
Concentration–discharge relationships of chlorophyll describe the origin and fluxes of river algae across ecoregions
Since 2017, the National Ecological Observatory Network (NEON) program provides an extensive network of automated instruments and field sampling at 34 different aquatic sites across the U.S. NEON data provides a rare opportunity to combine high-frequency measurements from sensors with physical samples collected at multiples sites from different biomes. Such combination of data is frequently available only for 1, or few, sites. NEON provides the necessary data to translate some of the methods and research previously applied to single sites to a large spatial and temporal scale. Our approach in this study was to obtain all the available and reliable data from NEON aquatic sites, and analyze high frequency measurements of Chlorophyl a (Chl a) concentration and turbidity during high flows with a common analytical procedure. Then, we relate these high flow patterns to watershed conditions and algal communities to elucidate the controls on river phytoplankton communities and fluxes. The data provided here summarizes multiple storm characteristics and C-Q metrics (hysteresis index) for Chl a and turbidity for several high flow events at 26 different NEON stream and river sites.
Anatoxin concentrations, algal assemblages, and water quality data for the South Fork Eel, Salmon, and Russian Rivers in northern California, 2022-2023
We collected this data to better understand the timing of peak benthic cyanobacterial mat occurrence (specifically taxa associated with anatoxin production, Microcoleus and Anabaena) and mat anatoxin concentrations in rivers. We sampled in northern California on the South Fork Eel, Salmon, and Russian Rivers biweekly in 2022, and the Salmon River biweekly and South Fork Eel weekly in 2023. During each sampling event, we conducted benthic cover surveys, measured in-situ water quality parameters (temperature, pH, dissolved oxygen, conductivity), and collected surface water samples and targeted cyanobacteria samples. In 2022 on all rivers and in 2023 at the Salmon River, we also collected distributed non-targeted periphyton samples to characterize full-reach community compositions. All sampling was completed in 150-m reaches upstream of sensors recording continuous dissolved oxygen, conductivity, and temperature data. We analyzed surface water samples for nitrate, ammonium, soluble reactive phosphate, total dissolved carbon, and dissolved organic carbon. We also analyzed surface water samples from 2022 for major anions (Cl, SO4, Br) and cations (Na, K, Mg, Ca). Targeted-cyanobacteria and non-target periphyton samples were analyzed for anatoxins (and two other classes of toxins, microcystins and cylindrospermopsins), relative abundance of algal taxa (via microscopy), ash-free dry mass, and chlorophyll-a. To estimate mean river depth within the dissolved oxygen footprint upstream of sensors, we kayaked portions of the river and collected river depth measurements. We also measured discharge at each river excluding the Salmon River (due to high discharge) and completed pebble counts at the South Fork Eel River to obtain sediment grain size distributions. Lastly, we estimated daily reach-scale river metabolism (gross primary productivity and ecosystem respiration) using data from dissolved oxygen sensors with the "streamMetabolizer" package in R at all sensor placements.
Laboratory study on microplastic fiber size and concentration effects on leopard frog (Lithobates pipiens) tadpole survival, development, behavior, and parasite susceptibility
This dataset contains comprehensive raw data from a completed laboratory experiment conducted from May 24 to June 30, 2021 (with additional analysis performed in 2025), investigating the effects of polyester microplastic (MP) fiber exposure on northern leopard frog (Lithobates pipiens) tadpoles and their interactions with echinostome trematodes (Echinostoma sp.). Tadpole egg masses were collected from a wetland in Indiana, USA, and ramshorn snails (Helisoma trivolvis), serving as trematode hosts, were collected from Tioga County, New York, USA. The experiment was conducted under controlled laboratory conditions using a static-renewal design, exposing tadpoles to short (~0.24 mm) or long (~1.50 mm) polyester MP fibers at concentrations of 0, 10, or 40 µg L⁻¹ for 32 days, followed by controlled exposure to echinostome cercariae. The dataset includes measurements of tadpole mortality, developmental traits (mass, snout-to-vent length, Gosner stage), behavioral activity (number of moving pre- and post-parasite exposure), MP fiber ingestion, and susceptibility to trematode infection (metacercarial cyst counts in kidneys). These data provide a resource for studying the ecological and toxicological impacts of microplastics on amphibian health, and host-parasite dynamics in freshwater ecosystems, making the dataset suitable for researchers in ecotoxicology, and disease ecology. The dataset is complete, with no ongoing data collection, and is designed to support analyses of microplastic-mediated effects on aquatic organisms.
Concentration of dissolved organic carbon in water samples taken from the Upper Clark Fork River (Montana, USA) during water year 2021 (1 Oct 2020 - 30 Sep 2021)
The Upper Clark Fork River (UCFR) Long Term Research in Environmental Biology (LTREB) umbrella monitoring project generating these data is conducted separately and complementarily to the 200-million-dollar (USD) superfund project for ecological restoration of the UCFR, associated tributaries, and head water streams including Silver Bow and Warm Springs Creeks. Restoration along the UCFR in western Montana includes removal of metal-laden floodplain soils, lowering of the floodplain to its original elevation, and re-vegetation of over 70 km of the river’s floodplain closest to contaminant sources. The UCFR LTREB project includes bi-weekly water quality monitoring across the first 200 km of the river and its major tributaries along a gradient of heavy metal contamination associated with historic mining. Monitoring includes inorganic phosphorus and nitrogen concentrations, biotic standing stocks, and dissolved and whole-water heavy metal concentrations. The monitoring program began in 2017 with funding extended through 2028. The original analytical intent for these data was to assess the response of river dissolved organic carbon to the floodplain restoration. Data are Aurora Total Organic Carbon combustion analyses of the concentration of organic carbon dissolved in filtered samples of well-mixed river thalweg water. Data are from the 2021 water year (1 Oct 2020 to 30 Sep 2021) from samples collected on the Upper Clark Fork River (USGS HUC 17010201) at project sites distributed along the river from the vicinity of Anaconda to Missoula, Montana, USA.
Concentration of dissolved organic carbon in water samples taken from the Upper Clark Fork River (Montana, USA) during water year 2023 (1 Oct 2022 - 30 Sep 2023)
The Upper Clark Fork River (UCFR) Long Term Research in Environmental Biology (LTREB) umbrella monitoring project generating these data is conducted separately and complementarily to the 200-million-dollar (USD) superfund project for ecological restoration of the UCFR, associated tributaries, and head water streams including Silver Bow and Warm Springs Creeks. Restoration along the UCFR in western Montana includes removal of metal-laden floodplain soils, lowering of the floodplain to its original elevation, and re-vegetation of over 70 km of the river’s floodplain closest to contaminant sources. The UCFR LTREB project includes bi-weekly water quality monitoring across the first 200 km of the river and its major tributaries along a gradient of heavy metal contamination associated with historic mining. Monitoring includes inorganic phosphorus and nitrogen concentrations, biotic standing stocks, and dissolved and whole-water heavy metal concentrations. The monitoring program began in 2017 with funding extended through 2028. The original analytical intent for these data was to assess the response of river dissolved organic carbon to the floodplain restoration. Data are total organic carbon combustion analyses (Shimadzu Scientific Instruments) of the concentration of organic carbon dissolved in filtered samples of well-mixed river thalweg water. Data are from the 2023 water year (1 Oct 2022 to 30 Sep 2023) from samples collected on the Upper Clark Fork River (USGS HUC 17010201) at project sites distributed along the river from the vicinity of Anaconda to Missoula, Montana, USA.
Concentration of dissolved organic carbon in water samples taken from the Upper Clark Fork River (Montana, USA) during water year 2024 (1 Oct 2023 - 30 Sep 2024)
The Upper Clark Fork River (UCFR) Long Term Research in Environmental Biology (LTREB) umbrella monitoring project generating these data is conducted separately and complementarily to the 200-million-dollar (USD) superfund project for ecological restoration of the UCFR, associated tributaries, and head water streams including Silver Bow and Warm Springs Creeks. Restoration along the UCFR in western Montana includes removal of metal-laden floodplain soils, lowering of the floodplain to its original elevation, and re-vegetation of over 70 km of the river’s floodplain closest to contaminant sources. The UCFR LTREB project includes bi-weekly water quality monitoring across the first 200 km of the river and its major tributaries along a gradient of heavy metal contamination associated with historic mining. Monitoring includes inorganic phosphorus and nitrogen concentrations, biotic standing stocks, and dissolved and whole-water heavy metal concentrations. The monitoring program began in 2017 with funding extended through 2028. The original analytical intent for these data was to assess the response of river dissolved organic carbon to the floodplain restoration. Data are total organic carbon combustion analyses (Shimadzu Scientific Instruments) of the concentration of organic carbon dissolved in filtered samples of well-mixed river thalweg water. Data are from the 2024 water year (1 Oct 2023 to 30 Sep 2024) from samples collected on the Upper Clark Fork River (USGS HUC 17010201) at project sites distributed along the river from the vicinity of Anaconda to Missoula, Montana, USA.
Concentration of dissolved organic carbon in water samples taken from the Upper Clark Fork River (Montana, USA) during water year 2022 (1 Oct 2021 - 30 Sep 2022)
The Upper Clark Fork River (UCFR) Long Term Research in Environmental Biology (LTREB) umbrella monitoring project generating these data is conducted separately and complementarily to the 200-million-dollar (USD) superfund project for ecological restoration of the UCFR, associated tributaries, and head water streams including Silver Bow and Warm Springs Creeks. Restoration along the UCFR in western Montana includes removal of metal-laden floodplain soils, lowering of the floodplain to its original elevation, and re-vegetation of over 70 km of the river’s floodplain closest to contaminant sources. The UCFR LTREB project includes bi-weekly water quality monitoring across the first 200 km of the river and its major tributaries along a gradient of heavy metal contamination associated with historic mining. Monitoring includes inorganic phosphorus and nitrogen concentrations, biotic standing stocks, and dissolved and whole-water heavy metal concentrations. The monitoring program began in 2017 with funding extended through 2028. The original analytical intent for these data was to assess the response of river dissolved organic carbon to the floodplain restoration. Data are primarily Aurora Total Organic Carbon combustion analyses of the concentration of organic carbon dissolved in filtered samples of well-mixed river thalweg water. A few samples from the final campaign in the dataset were analyzed with a Shimadzu instrument using a similar method. Data are from the 2022 water year (1 Oct 2021 to 30 Sep 2022) from samples collected on the Upper Clark Fork River (USGS HUC 17010201) at project sites distributed along the river from the vicinity of Anaconda to Missoula, Montana, USA.
Time series of total and soluble metal concentrations from Falling Creek Reservoir, Beaverdam Reservoir, and Carvins Cove Reservoir in southwestern Virginia, USA from 2014-2024
Depth profiles of total and soluble metals were sampled from 2014-2024 in three drinking-water reservoirs: Falling Creek Reservoir (FCR), Beaverdam Reservoir (BVR), and Carvins Cove Reservoir (CCR). FCR and BVR are located in Vinton, Virginia, USA and CCR is located in Roanoke, Virginia, USA. Only Fe and Mn were analyzed from 2014-2019. The full suite of metals (Li, Na, Mg, Al, Si, K, Ca, Fe, Mn, Cu, Sr, Ba) were analyzed from 2020-2024. All reservoirs are owned and operated by the Western Virginia Water Authority and are managed as drinking-water sources for the city of Roanoke, VA. The dataset includes metal samples that were collected along a depth profile taken at the deepest site of each reservoir near the dam. Additional samples were collected at a gauged weir located on the primary inflow tributary, as well as at a secondary tributary to FCR. A 2024 sampling campaign at FCR included outflow spillway surface water sampling. A 2022 sampling campaign at CCR included inflows and a partial depth profile at the deepest site. Sampling frequency in FCR and BVR in 2024 was approximately weekly during the summer and fall (May - October), approximately fortnightly during the spring (March - April), and approximately monthly during the winter (November - March). In 2022, sampling frequency at CCR was approximately fortnightly during summer and fall (May - October).
Time series of dissolved methane and carbon dioxide concentrations for Falling Creek Reservoir, Beaverdam Reservoir and Carvins Cove Reservoir in southwestern Virginia, USA during 2015-2025
Surface samples and depth profiles of carbon dioxide and methane concentrations were sampled from 2015 to 2025 in three drinking water reservoirs in southwestern Virginia, USA: Beaverdam Reservoir (Vinton, Virginia), Carvins Cove Reservoir (Roanoke, Virginia), and Falling Creek Reservoir (Vinton, Virginia). All three reservoirs are owned and operated by the Western Virginia Water Authority as primary or secondary drinking water sources for Roanoke, Virginia. The dataset consists of depth profiles of dissolved greenhouse gas (carbon dioxide, methane) samples measured at the deepest site of each reservoir adjacent to the dam. Additional surface samples were collected at a gauged weir on Falling Creek Reservoir's primary inflow tributary, from a wetland adjacent to Falling Creek Reservoir, and from the reservoir outflow. At Beaverdam Reservoir, additional samples were collected at three outflow sites below the dam and at the mid-reservoir outflow. Samples were collected approximately fortnightly from March-April, weekly from May-October, and monthly in November-February at Falling Creek Reservoir and Beaverdam Reservoir. Samples were collected twice in 2025 at Carvins Cove Reservoir. Additionally, upstream surface samples were taken at multiple tributaries in Carvins Cove Reservoir. In 2019, surface samples along the stream and reservoir continuum in both Falling Creek Reservoir and Beaverdam Reservoir were collected monthly during the summer stratified period. In 2025, littoral samples were collected from Falling Creek Reservoir monthly from June to October (see site descriptions file for geographic coordinates of sampling sites). A maintenance log and quality assurance/quality control analysis scripts accompany the data package.
Concentration and Age of Nonstructural Carbon Reserves in Two Trees at Harvard Forest 2012
We know surprisingly little about whole-tree nonstructural carbon (NSC; primarily sugars and starch) budgets. Even less well understood is the mixing between recent photosynthetic assimilates (new NSC) and previously stored reserves. And, NSC turnover times are poorly constrained. We characterized the distribution of NSC in the stemwood, branches, and roots of two temperate trees, and we used the continuous label offered by the radiocarbon (14C) bomb spike to estimate the mean age of NSC in different tissues. NSC in branches and outermost stemwood growth rings had the 14C signature of the current growing season. However, NSC in older above- and below-ground tissues was enriched in 14C, indicating that it was produced from older assimilates. Radial patterns of 14C in stemwood NSC showed strong mixing of NSC across the youngest growth rings, with limited.
Chloride and sulfate concentrations in 1918 Marsh, Madison, WI, 2012-2024
Beginning in 2012, chloride and sulfate concentrations were collected at a suite of sampling locations in and around 1918 Marsh, a small wetland on the University of Wisconsin–Madison campus from 2012-2024. Water temperature, water depth, and ice thickness are provided for each sampling event where applicable. Since fall 2014 water was collected via syringes, and filtered through a 25 mm 0.45µm GMF filter into plastic scintillation vials in the field. All samples were analyzed on an ion chromatograph (Dionex ICS 2100) using an electro-chemical suppressor. Prior to September 2014 samples were taken by dipping the opening of a plastic sample bottle below the surface and the sample was filtered in the Laboratory prior to chemical measurements. Samples were largely from the fall/winter season and taken at ca. 3-week intervals. In these early samples dissolved oxygen was also measured with a DO meter in the field. The University of Wisconsin–Madison deposits plowed snow each winter onto a gravel lot located adjacent to the snowpile. Photos of the snowpile from 2013 to 2024 are also provided, with a vertical pole for scale.
Spatial heterogeneity of within-stream methane concentrations North Temperate Lakes LTER, 2014
Streams, rivers, and other freshwater features may be significant sources of CH4 to the atmosphere. However, high spatial and temporal variabilities hinder our ability to understand the underlying processes of CH4 production and delivery to streams and also challenge the use of scaling approaches across large areas. We studied a stream having high geomorphic variability to assess the underlying scale of CH4 spatial variability and to examine whether the physical structure of a stream can explain the variation in surface CH4. A combination of high-resolution CH4 mapping, a survey of groundwater CH4 concentrations, quantitative analysis of methanogen DNA, and sediment CH4 production potentials illustrates the spatial and geomorphic controls on CH4 emissions to the atmosphere.
Chloride Concentrations, Conductivity, and Water Temperature Data from Lake Mendota and Lake Monona Madison, WI: December 2019 – April 2021
Conductivity and chloride were measured for 2 years in Lake Mendota and Lake Monona in Madison, WI. Conductivity was continuously measured (every 30 minutes) on under-ice buoys in the eplimnia (1-2m below the surface) and hypolimnia (1m off the bottom of the lake) of the lakes. Depth-discrete chloride grab samples were collected from the lakes quarterly. Profile sampling in Mendota, which is approximately 25 m deep, occurred every 5m from 0-20m and at 23.5m. Profile sampling in Monona, which is approximately 21m deep, occurred every 4m from 0-20m. This data was needed for a master’s research thesis with the goal of identifying the lakes' mixing dynamics and how salinization may impact them.
Nutrient concentrations in three small streams on the coast of the Delmarva Peninsula 2002-2009
This dataset contains dissolved nutrient measurements for three small creeks on the Atlantic side of the Delmarva Peninsula in Virginia.
Particulate organic carbon and particulate organic nitrogen concentrations and stable isotope composition of seawater sampled during the Antarctic Circumnavigation Expedition (ACE) during the Austral Summer of 2016/2017.
<p><strong>Dataset abstract</strong></p> <p>This dataset contains particulate organic carbon and particulate organic nitrogen concentrations and stable isotope composition (delta 13C and delta 15N) sampled during the Antarctic Circumnavigation Expedition (ACE) Leg 1-3. Water samples were collected from the underway seawater supply every 3 hours, filtered onto pre-combusted glass fibre filters, acidified to remove inorganic compounds and analysed for both elements on the same filter using an elemental analyser. These samples provide an estimate of the organic carbon and organic nitrogen concentration and carbon and nitrogen stable isotope composition of living and detrital particles > 0.7 micrometres in size.</p> <p><strong>Dataset contents</strong></p> <ul> <li>README.txt, metatdata, text</li> <li>data_file_header.txt, metadata, text</li> <li>ace_uw_poc_pon_blanks_20200512CURRSGCMR.csv, data file, comma-separated values</li> <li>ace_uw_poc_pon_20200512CURRSGCMR.csv, data file, comma-separated values</li> </ul>
Particle concentration data from: Long-term measurement of sub-3nm particles and their precursor gases in the boreal forest
<p>The knowledge of the dynamics of sub-3nm particles in the atmosphere is crucial for our understanding of first steps of atmospheric new particle formation. Therefore, accurate and stable long-term measurements of the smallest atmospheric particles are needed. In this study, we analyzed over five years of particle concentrations in size classes 1.1–1.7 nm and 1.7–2.5 nm obtained with the Particle Size Magnifier (PSM) and three years of precursor vapor concentrations measured with the Chemical Ionization Atmospheric Pressure Interface Time-of-Flight mass spectrometer (CI-APi-ToF) at the SMEAR II station in Hyytiälä, Finland. The results show that the 1.1–1.7 nm particle concentrations have a daytime maximum during all seasons, which is due to increased photochemical activity. There are significant seasonal differences in median concentrations of 1.7–2.5 nm particles, underlining the different frequency of new particle formation between seasons. Aerosol precursor vapors have notable diurnal and seasonal differences as well. Sulfuric acid and highly oxygenated organic molecule (HOM) monomer concentrations have clear daytime maxima, while HOM dimers have their maxima during the night. HOM concentrations for both monomers and dimers are the highest during summer and the lowest during winter. Higher median concentrations during summer result from increased biogenic activity in the surrounding forest. Sulfuric acid concentrations are the highest during spring and summer, with autumn and winter concentrations being two to three times lower. A correlation analysis between the sub-3nm concentrations and aerosol precursor vapor concentrations indicates that HOMs, particularly their dimers, and sulfuric acid play a significant role in new particle formation in the boreal forest. Our analysis also suggests that there might be seasonal differences in new particle formation pathways that need to be investigated further. </p> <p> </p>
Monthly aerosol emissions and GHG concentration projections from 2020-2025: modified SSP2-4.5 to account for COVID-19 impacts on sector activity
<p>This repository holds the netcdf files for emissions and concentrations projected by the scenario SSP2-4.5, from the Scenario4MIPs database (<a href="https://esgf-node.llnl.gov/search/input4mips/">https://esgf-node.llnl.gov/search/input4mips/</a>), modified by the country and sector activity levels associated with lockdown, projected out for 5 years after 2020. The details of these activity estimates are available from <a href="https://github.com/Priestley-Centre/COVID19_emissions">https://github.com/Priestley-Centre/COVID19_emissions</a>.</p> <p>The methodology behind these calculations is based on <a href="https://github.com/Rlamboll/modify_COVID19_netCDF_Emissions/">https://github.com/Rlamboll/modify_COVID19_netCDF_Emissions/tree/endof2020</a>, a slight modification of the approach used in <a href="https://zenodo.org/record/3947917#.XxR_qyhKhPZ">https://zenodo.org/record/3947917#.XxR_qyhKhPZ</a> to have a different timeframe. </p> <p>Funding was provided by the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement nos. 820829 (CONSTRAIN) <a href="http://constrain-eu.org/">http://constrain-eu.org/</a> </p>
Concentration of gaseous sulfuric acid measured over the Southern Ocean in the austral summer of 2016/2017, during the Antarctic Circumnavigation Expedition (ACE).
<p><strong>Dataset abstract</strong></p> <p>The authors would highly appreciate being contacted if the data is used for any purpose.</p> <p>We measured sulfuric acid concentration in the gas phase with a nitrate chemical ionization mass spectrometer (we used an APi-HTOF mass spectrometer produced by Tofwerk AG coupled with a Chemical ionization inlet A70 produced by Airmodus). Sulfuric acid is detected in the mass spectrometer either as a deprotonated ion or as a cluster with the reagent ion (NO3-). The concentration is calculated as the area of these two peaks normalized to the concentration of the reagent ions (monomer, dimer and trimer) and multiplied by a calibration factor that was experimentally derived at Paul Scherrer Institute in the summer 2017, after the campaign. In the atmosphere, sulfuric acid is produced by the oxidation of sulfur dioxide that could have both a natural or anthropogenic origin (e.g. phytoplankton emission or fossil fuel combustion). Sulfuric acid in the atmosphere is responsible for a very large fraction of the newly formed particles, therefore it is important to have accurate measurements of this vapour in remote places like the Southern Ocean to better understand secondary aerosol sources and processes.</p> <p>The data have been cleaned from the influence of the exhaust of the research vessel. Temporal coverage is from January 22, 2017 to March 19, 2017. There are no data for the first leg of the expedition because the instrument was not on the ship. The instrument was operated during leg 4 but data has not been processed yet as they require additional work due to some instrumental issues that affects their quality. Data were collected with one-second time resolution but integrated to five minutes to increase the signal to noise ratio.</p> <p>Concentrations are reported as molecules per cubic centimeter. The lower limit of detection is in the ppq (part per quadrillion) range but was not determined exactly as it varies with the integration time and background noise.</p> <p><strong>Dataset contents</strong></p> <ul> <li>gas_sulfuric_acid_concentration_data.csv, data file, comma-separated values</li> <li>data_file_header.txt, metadata, text format</li> <li>README.txt, metadata, text format</li> <li>change_log.txt, metadata, text format</li> </ul> <p>Data that were missing or bad because of instrumental problems were simply removed from the file (no entry).</p> <p><strong>Change log</strong></p> <p>v1.1 - data files updated</p> <ul> <li>re-analysis of the raw data with an improved mass spectra peak fitting routine, a different calibration factor was also applied to the data following a more detailed analysis of the calibration experiment</li> <li>use updated, corrected GPS data</li> </ul> <p>v1.0 - initial release of dataset</p>
Concentration of gaseous methanesulfonic acid measured over the Southern Ocean in the austral summer of 2016/2017, during the Antarctic Circumnavigation Expedition (ACE).
<p><strong>Dataset abstract</strong></p> <p>The authors would highly appreciate being contacted if the data is used for any purpose.</p> <p>We measured methanesulfonic acid concentration in the gas phase with a nitrate chemical ionization mass spectrometer (we used an APi-HTOF mass spectrometer produced by Tofwerk AG coupled with a Chemical ionization inlet A70 produced by Airmodus). Methanesulfonic acid is detected in the mass spectrometer either as a deprotonated ion or as a cluster with the reagent ion (NO3-). The concentration is calculated as the area of these two peaks normalized to the concentration of the reagent ions (monomer, dimer and trimer) and multiplied by a calibration factor that was experimentally derived at Paul Scherrer Institute in the summer 2017, after the campaign.</p> <p>In the atmosphere, methanesulfonic acid is produced by the oxidation of dimethyl sulfide that is mostly emitted in the atmosphere by phytoplankton. Methanesulfonic acid can contribute to the growth of aerosol particles by condensation or aqueous phase processing in clouds. The data have been cleaned from the influence of the exhaust of the research vessel. Temporal coverage is from 22 January 2017 to 19 March 2017. There are no data for the first leg of the expedition because the instrument was not on the ship. The instrument was operated during leg 4 but data has not been processed yet as they require additional work due to some instrumental issues that affects their quality. Data were collected with one-second time resolution but integrated to five minutes to increase the signal-to-noise ratio.</p> <p>Concentrations are reported as molecules per cubic centimeter. The lower limit of detection is in the ppq (part per quadrillion) range but was not determined exactly as it varies with the integration time and background noise.</p> <p><strong>Dataset contents</strong></p> <ul> <li>gas_methanesulfonic_acid_concentration_data.csv, data file, comma-separated values</li> <li>data_file_header.txt, metadata, text format</li> <li>README.txt, metadata, text format</li> <li>change_log.txt, metadata, text format</li> </ul> <p>There are no null values in the file. Data that were missing or bad because of instrumental problems were simply removed from the file (no entry).</p> <p><strong>Change log</strong></p> <p>v1.1 - data files updated</p> <ul> <li>re-analysis of the raw data with an improved mass spectra peak fitting routine, a different calibration factor was also applied to the data following a more detailed analysis of the calibration experiment</li> <li>use updated, corrected GPS data</li> </ul> <p>v1.0 - initial release of dataset</p>
ScienceDex guides
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These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.