ABSTRACT:

This resource includes conductivity, temperature, and specific conductance data for Northwest Branch Anacostia River near Colesville, MD. Data were collected for the purpose of cross-site comparison and correlating to other water quality parameters such as chloride. Conductivity and temperature were collected using a HOBO Fresh Water Conductivity Data Logger (Part # U24-001, Onset Computer Corp.) and converted to specific conductance at 25˚C. Data were collected at a 15-minute interval and downloaded manually every 60 days. The instrument is co-located with USGS stream gaging station 01650500. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes temperature data collected throughout the Dead Run stream network in Woodlawn, Baltimore County, MD. Data are being collected for the purpose of assessing the impacts of stormwater management facilities on the thermal regime of a Maryland Class IV stream. Temperature data are collected using HOBO TidbiT MX Temp 400 (MX2203) sensors (Part # MX2203, Onset Computer Corp.) secured to the streambed with rebar and zip ties. 169 sensors have been deployed at a spatial increment of 100 m over 16 km of stream length. Data are collected at a 5-minute interval and downloaded every ~150 days.

ABSTRACT:

This resource includes air temperature data collected at six stations in Dead Run watershed near Woodlawn, Baltimore County, MD. Data are being collected together with stream temperature data for the purpose of assessing the impacts of stormwater management facilities on the thermal regime of a Maryland Class IV stream. Air temperature data are collected using HOBO MX2305 Temperature Data Loggers (Part # MX2305, Onset Computer Corp.) protected by solar radiation shields (Part # RS1, Onset Computer Corp.), each mounted to a pole co-located with six USGS stream gaging stations. Data are collected at a 5-minute interval and downloaded via Blue Tooth every 90 days.

ABSTRACT:

This collection contains the following resource data sets for Dead Run watershed in Baltimore County, Maryland, USA: stream chemistry, stream temperature, stream depth, groundwater levels, groundwater chemistry, groundwater temperature, barometric pressure, air temperature, PAR (photosynthetic active radiation), soil gas data, soil moisture data, and subsurface permeability.

ABSTRACT:

This collection contains the following resource data sets for the NW Branch Anacostia watershed in Montgomery County, Maryland, USA: stream chemistry and stream temperature.

ABSTRACT:

This collection contains the following resource data sets for Pennypack Creek watershed in Philadelphia, Pennsylvania, USA: stream chemistry; shape files of watershed delineation.

ABSTRACT:

This resource includes water isotope data from Northwest Branch Anacostia River near Hyattsville MD (NWB1) and near Colesville, MD (NWB2), as well as precipitation data collected in University Park, MD. Stream grab samples are collected biweekly; precipitation samples are collected for every precipitation event. Samples are analyzed for d18O and d2H on a Picarro L 2120-i water isotope analyzer at UMBC. Data are collected for the purpose of (1) cross-site comparison with other sites in the Urban CZ cluster; (2) determination of the local meteoric water line; and (3) calculation of mean watershed transit times. Stream sampling sites are co-located with USGS stream gaging stations 01651000 (NWB1) and 01650500 (NWB2). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes water isotope data from Pennypack Creek at Lower Rhawn St Bridge, Philadelphia, PA (PPRH) and Pennypack Creek at Pine Road, at Philadelphia, PA (PPRI) as well as precipitation data collected in Fort Washington, PA. Stream grab samples are collected biweekly; precipitation samples are collected for every precipitation event. Samples are analyzed for d18O and d2H on a Picarro L2120-i water isotope analyzer at UMBC. Data are collected for the purpose of (1) cross-site comparison with other sites in the Urban CZ cluster; (2) determination of the local meteoric water line; and (3) calculation of mean watershed transit times. Stream sampling sites are co-located with USGS stream gaging stations 01467048 (PPRI) and 01467042 (PPPI). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes shapefiles of spatial features from Dead Run watershed in Baltimore County, Maryland. These data are frequently used in support of hydrologic observational and modeling studies. Layers include hydrography, watershed and subwatershed boundaries, fraction impervious surface area, and stream gage locations. The stream gage locations correspond to USGS stream gaging stations 01589317 (DR1), 01589316 (DR2), 01589320 (DR3), 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR).

ABSTRACT:

This resource includes trace gas data collected at three locations in the Dead Run stream network in Woodlawn, Baltimore County, MD. Dissolved gas species include CH4, N2O, CO2, and N2:Ar. Stream grab samples and ambient air samples are collected biweekly and analyzed for trace gas concentrations at the Cary Institute of Ecosystem Studies. Sampling stations are co-located with USGS stream gaging stations 01589312 (DR5), 01589315 (DR4), and 01589330 (DRKR). Protocols for sampling and analysis follow those of the National Ecological Observatory Network (NEON) and Cary Institute of Ecosystem Studies.

Dissolved gas measurements of streams coupled with groundwater can provide information on integrated source/sink dynamics within the urban critical zone. CO2 concentrations are driven by weathering reactions and biological activity. Nitrous oxide (N2O) is an index of nitrogen enrichment in the landscape. Methane (CH4) and dissolved nitrogen:argon (N2:Ar) indicate presence of anaerobic conditions and nitrogen sinks. Gas data can help determine the interplay between nitrogen inputs and processing in the urban critical zone. For example, high N2O (and nitrate) can provide evidence of a shift from a source-controlled to transport-controlled system. Low N2O (and low nitrate) along with high CH4 and high dissolved N2:Ar also can provide evidence of a similar shift but would suggest the presence of significant anaerobic sinks with implications about water pathways through the urban critical zone.

ABSTRACT:

This resource contains input files required to run ParFlow.CLM and EcoSLIM for Dead Run watershed, Baltimore County, MD. Model resolution for this instance is 40 m in the x-y direction, with variable dz. Both Parflow.CLM (v 3.9) and EcoSLIM (v 1.2) codes can be downloaded from GitHub. An edited version of the particle output file is also included in this resource.

ABSTRACT:

This resource includes water isotope data from Dead Run, Maryland as well as precipitation data collected in Oella, MD. Stream grab samples are collected weekly; precipitation samples are collected for every precipitation event. Samples are analyzed for d18O and d2H on a Picarro L 2120-i water isotope analyzer at UMBC. Data are collected for the purpose of (1) cross-site comparison with other sites in the Urban CZ cluster; (2) determination of the local meteoric water line; and (3) calculation of mean watershed transit times. Stream sampling sites are co-located with USGS stream gaging stations 01589317 (DR1), 01589316 (DR2), 01589320 (DR3), 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes stream chemistry for Dead Run, Baltimore County, Maryland. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are collected biweekly and analyzed for alkalinity, total organic carbon, dissolved organic carbon, total nitrogen, total dissolved nitrogen, bromide, chloride, fluoride, nitrate-nitrogen, nitrite-nitrogen, orthophosphate phosphorous, and sulfate. Stream sampling sites are co-located with USGS stream gaging stations 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR). Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes data from soil moisture, conductivity, and oxygen sensors deployed at three soil depths, in both upland and riparian zone sites in the headwaters of Dead Run watershed. Data are collected at an interval of 5 minutes and downloaded manually every 2-4 weeks. The purpose of the measurements is to examine soil water and oxygen content at nested depths across gradients of incision and topography.

ABSTRACT:

This resource includes stream chemistry for Dead Run, Baltimore County, Maryland. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are collected biweekly and analyzed on an ICPMS for 38 dissolved metals and metalloids. Stream sampling sites are co-located with USGS stream gaging stations 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR). Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes shapefiles of spatial features from Pennypack Creek watershed, in Bucks, Montgomery and Philadelphia Counties, PA, USA. These data are frequently used in support of hydrologic observational and modeling studies. Layers include hydrography, watershed and subwatershed boundaries, fraction impervious surface area, and stream gage locations. The stream gage locations correspond to USGS stream gaging stations 01467042 (Pine Road) and 01467048 (Lower Rhawn).

ABSTRACT:

This resource includes shapefiles of spatial features from Anacostia NW Branch watershed in Montgomery and Prince George's Counties, MD, USA. These data are frequently used in support of hydrologic observational and modeling studies. Layers include hydrography, watershed and subwatershed boundaries, fraction impervious surface area, and stream gage locations. The stream gage locations correspond to USGS stream gaging stations 01650500 (Colesville) and 01651000 (Hyattsville).

ABSTRACT:

This resource includes shapefiles of spatial features from Difficult Run in Fairfax County, VA, USA. These data are frequently used in support of hydrologic observational and modeling studies. Layers include hydrography, watershed and subwatershed boundaries, fraction impervious surface area, and stream gage locations. The stream gage locations correspond to USGS stream gaging stations 01645704 (Fox Lake), 01645762 (Vienna), and 01646000 (Great Falls).

ABSTRACT:

This resource includes shapefiles of spatial features from Swift Creek watershed, Wake County, NC, USA. These data are frequently used in support of hydrologic observational and modeling studies. Layers include hydrography, watershed and subwatershed boundaries, fraction impervious surface area, and stream gage locations. The stream gage location corresponds to USGS stream gaging station 02087580 (Apex).

ABSTRACT:

This top-level collection serves as a root location for the five watershed collections of the Urban Critical Zone Collaborative Research: Network Cluster: Anacostia NW Branch, Dead Run, Difficult Run, Pennypack Creek, and Swift Creek.

ABSTRACT:

This collection contains resource data sets for Swift Creek watershed, Wake County, NC, USA.

ABSTRACT:

This collection contains resource data sets for Difficult Run watershed, Fairfax County, VA, USA.

ABSTRACT:

This resource includes stream chemistry for Northwest Branch Anacostia River, Prince Georges and Montgomery Counties, Maryland. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are collected biweekly and analyzed for alkalinity, total organic carbon, dissolved organic carbon, total nitrogen, total dissolved nitrogen, bromide, chloride, fluoride, nitrate-nitrogen, nitrite-nitrogen, orthophosphate phosphorous, and sulfate. Stream sampling sites are co-located with USGS stream gaging stations 1651000 (NWB1) and 01650500 (NWB2). Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes stream chemistry for Pennypack Creek, Philadelphia County, Pennsylvania. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are collected biweekly and analyzed for alkalinity, total organic carbon, dissolved organic carbon, total nitrogen, total dissolved nitrogen, bromide, chloride, fluoride, nitrate-nitrogen, nitrite-nitrogen, orthophosphate phosphorous, and sulfate. Stream sampling sites are co-located with USGS stream gaging stations 01467048 (PPRH) and 01467042 (PPPI). Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes stream chemistry for the NW Branch Anacostia River, Prince George's and Montgomery Counties, MD. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are collected biweekly, as well as longitudinal synoptics 2-3 times per year, and analyzed on an ICPMS for 38 dissolved metals and metalloids. Stream sampling sites are co-located with USGS stream gaging stations 1651000 (NWB1) and 01650500 (NWB2). Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes stream chemistry for Pennypack Creek, Philadelphia and Montgomery Counties, Pennsylvania. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Stream grab samples are analyzed on an ICPMS for 38 dissolved metals and metalloids. Biweekly stream sampling sites are co-located with USGS stream gaging stations 01467048 (PPRH) and 01467042 (PPPI). Synoptic sampling is carried out along the entire main stem (from PPRH upstream) over the span of several hours after a long dry period, approximately twice per year. Data are collected for the purpose of (1) trend analysis as a function of space and time; (2) evaluation of the effects of regional geology, anthropogenic perturbations, and weathering processes on stream chemistry; and (3) comparison with stream chemistry from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes total suspended solids (TSS) data for Pennypack Creek, Philadelphia County, Pennsylvania. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network. Storms are sampled using ISCO samplers to obtain 1-liter samples in 15 - 60 minute intervals over the course of a storm. Samples are filtered and dried in the lab to determine the mass of suspended solids contained in each 1-liter sample, and converted to TSS in mg/L. Sampling sites are co-located with USGS stream gaging stations 01467048 (PPRH) and 01467042 (PPPI). Data are collected for the purpose of comparison with TSS data from other sites in the Urban CZ cluster.

ABSTRACT:

This resource includes nitrate isotope data from Dead Run, Maryland. Stream grab samples are collected biweekly and are analyzed for d15N-Nitrate and d18O-Nitrate. Data are collected for the purpose of cross-site comparison with other sites in the Urban CZ cluster. Stream sampling sites are co-located with USGS stream gaging stations 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes nitrate isotope data from Pennypack Creek, Philadelphia, PA. Stream grab samples are collected biweekly and are analyzed for d15N-Nitrate and d18O-Nitrate. Data are collected for the purpose of cross-site comparison with other sites in the Urban CZ cluster. Sampling sites are co-located with USGS stream gaging stations 01467048 (PPRH) and 01467042 (PPPI). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes nitrate isotope data from Northwest Branch Anacostia River, Maryland. Stream grab samples are collected biweekly and are analyzed for d15N-Nitrate and d18O-Nitrate. Data are collected for the purpose of cross-site comparison with other sites in the Urban CZ cluster. Stream sampling sites are co-located with USGS stream gaging stations 1651000 (NWB1) and 01650500 (NWB2). This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes water quality data from synoptic sampling of streams and wells in Dead Run watershed, Baltimore County, MD. The stream network was sampled from the outlet at Dead Run Franklintown (DRKR) to the headwaters (Winters Lane in DR5) every 50 m over 5 km, after approximately 10 days of no rain, 2 to 3 times per year from 2014 - 2017. In addition, DR5 headwaters were sampled every 50 m over 1 km approximately monthly from 2017 - 2020. A network of 35 point piezometers in the DR5 subwatershed were also sampled 2-3 times per year from 2017 - 2020. Stream and well samples were analyzed for chloride, fluoride, nitrate-nitrogen and sulfate on a Dionex ion chromatography system. A subset of samples was also analyzed for d18O and d2H on a Picarro 2120-i water isotope analyzer. Three of the synoptic sampling sites are co-located with USGS stream gaging stations 01589315 (DR4), 01589312 (DR5), and 01589330 (DRKR).

ABSTRACT:

Photosynthetically Active Radiation (PAR) data have been collected at multiple sites in Dead Run watershed (near Woodlawn, MD) over variable periods of time since June 2012. The deployed device is a Photosynthetic Light (PAR) Smart Sensor S-LIA-M003 by Onset. The sensor measures light intensity for frequencies relevant to photosynthesis in units of µmol/m2/sec. Sensor specifications are posted at http://www.onsetcomp.com/products/sensors/s-lia-m003. Sensors are configured to collect data at a 5-minute interval. Data are stored in an Onset Microstation Data Logger H21-002 or H21-USB and downloaded manually every 60 days.

ABSTRACT:

This is an update to the technical report written by Aditi Bhaskar in 2010, "Getting Started with ParFlow: Dead Run, Baltimore Maryland Example", published as Technical Report 2010/002 by Center for Urban Environmental Research and Education at UMBC. This document details how to apply ParFlow.CLM to the example of a small urban watershed in Baltimore, Maryland: Dead Run. Instructions are provided for necessary software downloads and installations, pre-processing steps for DEM, generation of the necessary input files, setting up the problem input script and visualizing the resulting output using VisIt. The report takes the reader from beginning to end, from readings on ParFlow.CLM and steps for download and installation, through running the Dead Run example model. This material is intended to complement the extensive ParFlow documentation available on GitHub.

ABSTRACT:

Soil/saprolite cores were collected at eight hilltop locations in the headwater area of Dead Run watershed in Baltimore County, MD, and evaluated for hydraulic conductivity and total porosity. The lithology consists of Mount Washington Amphibolite (mafic rock) transitioning to the Potomac Group of the Fall Zone. Cores were collected using an AMS 10.2 cm-diameter steel auger bucket, in increments of about 15 cm, to depth of refusal. The length of the soil cores ranged from 1.4 m to 6.5 m. Each ~1200 cm3 sample was evaluated in the laboratory for hydraulic conductivity (K) using a UMBC/CUERE-designed falling-head permeameter and the Hvorslev equation. For each of 180 samples, 6 measurements were taken and corrected to a water temperature of 20˚C. Average K values ranged from 10-9 to 10-5 m/sec, with a geometric mean of 4.9x10-7 m/sec and an lnK variance of 2.7. The pattern of hydraulic conductivity varied with depth. K decreased by ~ 1-2 orders of magnitude to a depth of about 0.5 m. As the soil transitioned to saprolite, K values then increased by 1-2 orders of magnitude to depths of 2 - 2.5 m. For longer cores, a decrease in K values of 1-2 orders of magnitude was observed below 2.5 m, followed further zonal order-of-magnitude increases/decreases over 1-2 m depths. Results illustrate pronounced zonal heterogeneity of hydraulic conductivity for this system. As observed at other field sites, hydraulic conductivity values were log-normally distributed. Total porosity was determined on the same samples using a Teros 12 soil moisture sensor. Four measurements were taken. Average total porosity ranged from 0.31 to 0.53, with a mean of 0.45 and variance of 0.0016. Total porosity generally decreased with depth (0.1 – 1m), followed by an increase and then leveling off to a relatively constant value with depth. The zonal heterogeneity of total porosity was most prominent from 1-2 m, as opposed to hydraulic conductivity, which exhibited zonal heterogeneity with greater depths for longer core samples.

ABSTRACT:

This resource includes dissolved CO2 data in Dead Run, Baltimore County, MD. A eosGP:CO2 probe waterproof to 3 m (2020 version) was deployed at Dead Run Franklintown (DRKR) to collect dissolved CO2 data at a 5-minute frequency. Raw data were corrected with known gas concentrations of CO2 using the Eosense calibration procedure and then corrected using the eosense post-processing prortocol. Data used in the post-processing protocol include barometric pressure, water temperature, and water depth. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes barometric pressure data measured at several locations in Dead Run watershed, Baltimore County, Maryland. The data have been collected intermittently for various purposes including (1) correction of water pressure for calculating stream water level (pressure head); (2) post-processing of stream CO2 sensor data ; and (3) stream metabolism calculations. Data were collected using a Hobo 13-Foot Water Level Data Logger (Part # U20-001-04, Onset Computer Corp.) deployed in air. Data were collected at a 5-minute interval and downloaded manually every 60 days. The instruments are co-located with stream gaging stations. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes water quality sensor data measured at multiple locations in Dead Run, Baltimore County, Maryland. Stream temperature, specific conductance, turbidity, dissolved oxygen, pH, and nitrate data are collected for multiple purposes including (1) computation of watershed-scale export mass fluxes; (2) evaluation of event-based water quality /discharge behavior, and (2) stream metabolism calculations. Data are collected using various instruments including (1) YSI 6920 V2 sondes outfitted with temperature, specific conductance, and dissolved oxygen sensors; (2) YSI EXO2 sondes outfitted with temperature, specific conductance, dissolved oxygen and pH sensors; (3) Onset Inc. U24-001 conductivity/ temperature and U26-001 dissolved oxygen data loggers; and (4) SUNA nitrate-nitrogen analyzers. Data are collected at a 5-minute interval (SUNAs at a 30-minute interval) and either telemetered to UMBC (YSI sondes and SUNAs) or downloaded manually every 60 days (Onset loggers). The instruments are co-located with either USGS or UMBC stream gaging stations. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network and is associated with the Gwynns Falls sensor data set supported by Department of Energy. Dead Run data are backlogged to 2010 and are being reviewed and uploaded in ~2023-2024.

ABSTRACT:

This resource includes conductivity, temperature, and specific conductance data for Swift Creek near Apex, NC. Data were collected for the purpose of cross-site comparison and correlating to other water quality parameters such as chloride. Conductivity and temperature were collected using a HOBO Fresh Water Conductivity Data Logger (Part # U24-001, Onset Computer Corp.) and converted to specific conductance at 25˚C. Data were collected at a 15-minute interval and downloaded manually every 60 days. The instrument is co-located with USGS stream gaging station 02087580. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes water isotope data from Swift Creek, North Carolina. Stream grab samples are collected semiannually to annually as a synoptic spanning one day. Samples are analyzed for d18O and d2H on a Picarro L 2120-i water isotope analyzer at UMBC. Data are collected for the purpose of cross-site comparison with other sites in the Urban CZ cluster. The furthest downstream sampling sites is co-located with USGS stream gaging stations 02087580. This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This resource includes turbidity data measured at five USGS gaging stations in Dead Run, Baltimore County, Maryland. Data were collected with a YSI EXO2 sonde outfitted with a turbidity sensor from 2013- 2016. The collection interval was initially 30 minutes then switched to 5 minutes beginning in 2015. Suspended sediment was collected using ISCO samplers for the purpose of establishing correlations between turbidity and suspended sediment concentration, thus yielding a continuous record of suspended sediment concentration. Instantaneous sediment mass flux was calculated from the product of USGS instantaneous discharge data and suspended sediment concentration. Aggregation of data to monthly and annual mass loads and yields from 2013 to 2016 is presented in Kemper et al 2019. This resource is intended to provide data cited in Kemper et al 2019 to replace the https://doi.org/10.4211/his-5653 citation.

ABSTRACT:

The Baltimore radar rainfall dataset was developed from a multi-sensor analysis combining radar rainfall estimates from the Sterling, VA WSR88D radar (KLWX) with measurements from a collection of ground based rain gages. The archived data have a 15-minute time resolution and a grid resolution of 0.01 degree latitude/longitude (approximately 1 km x 1 km); 15-minute rainfall accumulations for each grid are in mm. The dataset spans 22 years, 2000-2021, and covers an area of approximately 4,900 km^2 (70 by 70 grids, each with approximate area of 1 km^2) surrounding the Baltimore, MD metropolitan area (Figure 1). The rainfall data cover the six months from April to September of each year. This is the period with most intense sub-daily rainfall and the period for which radar measurements are most accurate. Figure 1 illustrates the climatological analyses of mean annual frequency of days with at least 1 hour rainfall exceeding 25 mm. The striking spatial variability of convective rainfall is illustrated in Figure 2 by the April-September climatology of annual lightning strikes.

As with many long-term environmental data sets, sensor technology has changed during the time period of the archive. The Sterling, VA WSR88D radar underwent a hardware upgrade from single polarization to dual polarization in 2012. Prior to the upgrade, rainfall was estimated using a conventional radar-reflectivity algorithm (HydroNEXRAD) which converts reflectivity measurements in polar coordinates from the lowest sweep to rainfall estimates on a 0.01 degree latitude-longitude grid at the surface (see Seo et al. 2010 and Smith et al. 2012 for details on the algorithm). The polarimetric upgrade introduced new measurements into the radar-rainfall algorithm. In addition to reflectivity, the operational rainfall product, Digital Precipitation Rate (DPR), directly uses differential reflectivity and specific differential phase shift measurements to estimate rainfall (https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.ncdc:C00708; see also Giangrande and Ryzhkov 2008). Details of the algorithm structure and parameterization for the DPR radar-rainfall estimates have been modified during the 10-year period of the data set.

A storm-based (daily) multiplicative mean field bias has been applied to both datasets. The mean field bias is computed as the ratio of daily rain gage rainfall at a point to daily radar rainfall for the bin that contains the gage. The rain gage dataset is compiled from rain gages in the Baltimore metropolitan region and surrounding areas and includes gages acquired from both Baltimore City and Baltimore County, and the Global Historical Climatology Network daily (GHCNd). Mean field bias improves rainfall estimates and diminishes the impacts of changing measurement procedures.

The dataset has been archived in 2 formats: netCDF gridded rainfall, 1 file for each 15-minute time period, and csv or excel format point rainfall (1 point at the center of each grid) in a timeseries format with 1 file per calendar month covering the entire 70x70 domain. The csv files are in folders organized by calendar year. The first five columns in each file represent year, month, day, hour, and minute and can be combined to generate a unique date-time value for each time step. Each additional column is a complete time series for the month and represents data from one of the 1-km2 grid cells in the original data set.

The latitude and longitude coordinates for each pixel in the grid are provided. The latitude and longitude represent the centroid of the cell, which is square when represented in latitude and longitude coordinates and rectangular when represented in other distance-based coordinate systems such as State Plane or Universal Transverse Mercator. There are 4900 pixels in the domain. In order to visualize the data using GIS or other software, the user needs to associate each column in the annual rainfall file with the latitude and longitude values for that grid cell number.

These data may be subject to modest revision or reformatting in future versions. The current version is version 2.0 and is being offered to users who wish to explore the data. We will revise this document as needed.

ABSTRACT:

This resource includes water isotope data from Pond Branch at Oregon Ridge, Baltimore County, MD, USA. Stream grab samples are collected weekly to biweekly. Samples are analyzed for d18O and d2H on a Picarro L 2120-i water isotope analyzer at UMBC. Data are collected for the purpose of (1) providing a forested reference site for cross-site comparison with urban sites in the Urban CZ cluster; and (2) calculation of mean watershed transit times by analysis in combination with local precipitation water isotope data. The stream sampling site is co-located with USGS stream gaging station 01583570 This data set is part of the Urban Critical Zone Cluster in the NSF Critical Zone Collaborative Network.

ABSTRACT:

This collection contains resource data sets for Pond Branch watershed in Baltimore County, Maryland, USA:

ABSTRACT:

This resource contains groundwater level data from 39 wells in Dead Run watershed near Woodlawn, MD, USA. Boreholes (51-mm diameter) were drilled using a Shaw backpack portable drill, with 25.4-mm ID PVC pipes inserted to serve as wells, each screened 0.3048 m at its lower end. Wells are installed in pairs with bottom elevations differing by about 1 to 3 m. Well pairs are installed either in the riparian zone or at the hilltop, relative to the Dead Run channel. Between 4 and 8 wells comprise a transact perpendicular to the stream. Wells are outfitted with vanEssen Micro-Diver pressure transducers. Barometric pressure is measured at one location using a vanEssen Baro-Diver. Groundwater level below land surface is calculated from site-specific information on location of the pressure transducer sensor point below land surface. Pressure transducer data are recorded at 5-minute intervals. Instruments were deployed in 2015 and maintained until failure or end of a project. Manual downloads of water pressure data are done every 5 months; downloads of barometric pressure data are done every 2.5 months. The wells are located in the Piedmont physiographic province, in suburban Baltimore, Maryland, USA in either saprolite or highly weathered fractured bedrock.

ABSTRACT:

This resource includes water quality sensor data measured at three stations along the main stem of the Gwynns Falls watershed, spanning an urban to rural gradient of development from Baltimore City to Baltimore County, MD, USA. In addition, two forested reference sites, Baisman Run and Pond Branch at Oregon Ridge, and one urban site, Dead Run (tributary to Gwynns Falls), are instrumented in Baltimore County, MD, USA. Sensor data are collected at a 5-minute frequency by YSI EXO2 sondes that include temperature, specific conductance, turbidity, dissolved oxygen, and pH. In addition, s::can spectrolyser v3 sondes are planned for deployment to measure nitrate-nitrogen and dissolved organic carbon at a 15-minute frequency at 5 of the sites. A Seabird SUNA is currently measuring nitrate-nitrogen at Dead Run at a 30-minute frequency. All Dead Run data are provided in a separate linked resource. High frequency data are collected for the purpose of evaluating event-based water quality /discharge behavior, as a complement to weekly grab-sample stream chemistry data that have been collected by the Baltimore Ecosystem Study since 1998. The six sites are co-located with USGS stream gages. Data are telemetered to UMBC. This data set is part of the Baltimore Social-Environmental Collaborative Urban Integrated Field Laboratory supported by Department of Energy as well as the Critical Zone Collaborative Network supported by NSF.