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This data release contains hourly means of climatological data collected by the U.S. Geological Survey (USGS) from 10/1/1991 to 9/30/2019 at three weather stations in the Loch Vale watershed in Rocky Mountain National Park (RMNP), Colorado. In order of increasing elevation, the three weather stations are Loch Vale meteorological station at RMNP, Colo. (Main weather station, USGS station 401719105394311) at an elevation of 2,925 meters (m) above North American Vertical Datum of 1988 (NAVD 88), Andrews Creek meteorological station at RMNP, Colo. (Andrews Creek weather station, USGS station 401723105400101) at an elevation of 2,990 m above NAVD 88 and Sharkstooth meteorological station at RMNP, Colo. (Sharkstooth weather...
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This research focuses on understanding processes controlling temporal and spatial variability in aquatic carbon fluxes in headwater streams. Headwater streams are areas of active carbon cycling because of steep topographic gradients, complex soil and vegetation patterns, and an abundance of small lakes and streams. The project will combine information from the following major components: High-frequency measurements of aquatic carbon fluxes using in-stream sensors will provide information on temporal dynamics at unprecedented resolution. A geostatistical model will be developed to characterize relations between landscape type (e.g., wetlands, forest, tundra) and aquatic C dynamics and fluxes. Variations in fluxes...
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Atmospheric deposition of reactive nitrogen (Nr) due to human activities can have measurable effects on ecosystem processing and export of nutrients, groundwater and surface-water quality. Rates of Nr deposition to lower-elevation forests immediately adjacent to the Denver/Boulder urban area, however, have only recently been measured. The focus of this study was to determine the extent of urban and agricultural N pollution transport to the Colorado Front Range. In conjunction with the Network for Urban Atmospheric Nitrogen Chemistry (NUANC) and the National Atmospheric Deposition Program (NADP), we measured wet-plus-dry Nr deposition and evaluated spatial and seasonal variations in N deposition along an elevational...
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This data release includes simulation output from SnowModel (Liston and Elder, 2006), a well-validated process-based snow modeling system, and supporting snow, meteorological, and streamflow observations from the water years 2011 through 2015 (October 1, 2010, through September 30, 2015) across a 3,600 square kilometer model domain in the north-central Colorado Rocky Mountains. For each water year, SnowModel simulations were completed for a (1) baseline simulation, (2) bark-beetle disturbance condition simulation, (3) 2016 - 2035 future climate condition simulation (S1), and (4) 2046 - 2065 future climate condition simulation (S2). Sexstone and others (2018) provide details and summarize findings from each of the...
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Note: this data release has been superseded by version 3.0, available here: https://doi.org/10.5066/P9R29VUZ. This data release contains water-quality and discharge data collected at seven stream sites and one groundwater spring in Rocky Mountain National Park (RMNP), Colorado by the U.S. Geological Survey (USGS) from 10/1/2010 to 9/30/2019 using in-situ sensors and field meters. Data were collected for the purpose of quantifying downstream transport of aquatic carbon and exchange fluxes of dissolved carbon dioxide (CO₂) from streams. Parameters include daily mean discharge, dissolved CO₂, water temperature, atmospheric pressure, dissolved oxygen, fluorescent dissolved organic matter (fDOM), nitrate, specific conductance,...
Concentrations of weathering products in streams often show relatively little variation compared to changes in discharge, both at event and annual scales. In this study, several hypothesized mechanisms for this “chemostatic behavior� were evaluated, and the potential for those mechanisms to influence relations between climate, weathering fluxes, and CO2 consumption via mineral weathering was assessed. Data from Loch Vale, an alpine catchment in the Colorado Rocky Mountains, indicates that cation exchange and seasonal precipitation and dissolution of amorphous or poorly crystalline aluminosilicates are important processes that help regulate solute concentrations in the stream; however, those processes have no...
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This data release contains water-quality and discharge data collected at seven stream sites and one groundwater spring in Rocky Mountain National Park (RMNP), Colorado by the U.S. Geological Survey (USGS) from 10/1/2010 to 9/30/2019 using in-situ sensors and field meters. Data were collected for the purpose of quantifying downstream transport of aquatic carbon and exchange fluxes of dissolved carbon dioxide (CO₂) from streams. Parameters include daily mean discharge, dissolved CO₂, water temperature, atmospheric pressure, dissolved oxygen, fluorescent dissolved organic matter (fDOM), nitrate, specific conductance, turbidity, and corrected fDOM from 10/1/2010 to 9/30/2019 (DailyData.csv). Hourly mean dissolved CO₂,...
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This dataset includes discrete water quality and discharge data for three streams that flow through wetlands. There are two measurement and sampling locations on each stream: one immediately upstream from the wetland and one immediately downstream from the wetland. Measurements and sample collection occurred in 2010 and 2011 at West Twin Creek, AK; in 2019 and 2020 at Allequash Creek, WI; and in 2013, 2014, and 2017 at the Big Thompson River, CO. The upstream and downstream data from Allequash Creek and the Big Thompson River are from established USGS sites. At Allequash Creek, the downstream site is USGS 05357206 Allequash Creek Site No. 3 Nr Boulder Junction, WI, and the upstream site is USGS 5357205 Allequash...
Stable sulfur isotope ratios and major ions in bulk snowpack samples were monitored at a network of 52 high-elevation sites along and near the Continental Divide from 1993 to 1999. This information was collected to better define atmospheric deposition to remote areas of the Rocky Mountains and to help identify the major source regions of sulfate in winter deposition. Average annual δ34S values at individual sites ranged from +4.0 to +8.2‰ and standard deviations ranged from 0.4 to 1.6‰. The chemical composition of all samples was extremely dilute and slightly acidic; average sulfate concentrations ranged from 2.4 to 12.2 μeq l−1 and pH ranged from 4.82 to 5.70. The range of δ34S values measured in...
This webinar is part of a series featuring South Central Climate Science Center researchers studying the Rio Grande, a critical water resource for people and wildlife. Learn more at southcentralclimate.org and view the other webinars in this series here.
Organic carbon (OC) burial in lacustrine sediments represents an important sink in the global carbon cycle; however, large-scale OC burial rates are poorly constrained, primarily because of the sparseness of available data sets. Here we present an analysis of OC burial rates in water bodies of the conterminous U.S. (CONUS) that takes advantage of recently developed national-scale data sets on reservoir sedimentation rates, sediment OC concentrations, lake OC burial rates, and water body distributions. We relate these data to basin characteristics and land use in a geostatistical analysis to develop an empirical model of OC burial in water bodies of the CONUS. Our results indicate that CONUS water bodies sequester...
Relations between stream water chemistry and topographic, vegetative, and geologic characteristics of basins were evaluated for nine alpine/subalpine basins in Rocky Mountain National Park, Colorado, to identify controlling parameters and to better understand processes governing patterns in stream water chemistry. Fractional amounts of steep slopes (≥30°), unvegetated terrain, and young surficial debris within each basin were positively correlated to each other. These terrain features, which commonly occur on steep valley side slopes underlain by talus, were negatively correlated with concentrations of base cations, silica, and alkalinity and were positively correlated with nitrate, acidity, and runoff. These...
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Note: this data release has been superseded by version 2.0, available here: https://doi.org/10.5066/P9S775Y4. This data release contains water-quality and discharge data collected in Rocky Mountain National Park (RMNP), Colorado by the U.S. Geological Survey (USGS) from 10/1/2010 through 9/30/2019 using in-situ sensors and field meters. Data were collected for the purpose of quantifying exchange fluxes of dissolved carbon dioxide (CO₂) from streams. Parameters include daily mean dissolved CO₂, water temperature, atmospheric pressure, and discharge at seven stream sites and one groundwater spring (DailyData.csv). Hourly mean dissolved CO₂, CO₂ partial pressure (pCO2), water temperature, atmospheric pressure, and...
High-elevation lakes in the western United States are sensitive to atmospheric deposition of sulfur and nitrogen due to fast hydrologic flushing rates, short growing seasons, an abundance of exposed bedrock, and a lack of well-developed soils. This sensitivity is reflected in the dilute chemistry of the lakes, which was documented in the U.S. Environmental Protection Agency's Western Lake Survey of 1985. Sixty-nine lakes in seven national parks sampled during the 1985 survey were resampled during fall 1999 to investigate possible decadal-scale changes in lake chemistry. In most lakes, SO4 concentrations were slightly lower in 1999 than in 1985, consistent with a regional decrease in precipitation SO4 concentrations...
Sulphur 35, a cosmogenically produced radioisotope with a short half-life (87 days), was measured in snowpack during 1993–1997 and at four locations within the Loch Vale watershed during 1995–1997. The four sites include the two main drainages in the watershed, Andrews Creek and Icy Brook, a small south facing catchment flowing into Andrews Creek (Andrews Spring 1), and a similar north facing catchment flowing out of a scree field into Icy Brook (Spring 19). Concentrations ranged from a high of almost 50 mBq/L for a sample from Spring 19 in June 1996 to a concentration near the detection limit for a sample from Andrews Creek in April 1997. Sulphur 35 concentrations were normalized to sulphate (as mBq/mg SO4−2)...
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The transport of dissolved organic matter (DOM) by rivers is an important component of the global carbon cycle, affects ecosystems and water quality, and reflects biogeochemical and hydrological processes in watersheds. Understanding the fundamental relationships between discharge and DOM concentration and composition reveals important information about watershed flow paths, soil flushing, connectivity to riparian zones, organic matter leaching, soil moisture, and climatic influences. Data to describe these processes - both magnitude and timing - is critical for modeling and predicting watershed DOM dynamics, particularly in light of land use and climate change . Despite several decades of data collection, a synthesis...
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Recent studies have found insignificant or decreasing trends in time-series dissolved organic carbon (DOC) datasets, questioning the assumption that long-term DOC concentrations in surface waters are increasing in response to anthropogenic forcing, including climate change, land use, and atmospheric acid deposition. We used the Weighted Regressions on Time, Discharge, and Season (WRTDS) model to estimate annual flow-normalized (FN) concentrations and fluxes to determine if changes in DOC quantity and quality signal anthropogenic forcing at 10 locations in the Mississippi River Basin (MRB). Despite increases in agriculture and urban development throughout the basin, net increases in DOC concentration and flux were...
Categories: Publication; Types: Citation
Seasonal streamflow forecast bias, changes in climate, snowpack, and land cover, and the effects of these changes on relations between basin‐wide snowpack, SNOw TELemetry (SNOTEL) station snowpack, and seasonal streamflow were evaluated in the headwaters of the Rio Grande, Colorado. Results indicate that shifts in the seasonality of precipitation and changing climatology are consistent with periods of overprediction and underprediction in streamflow forecasts. Multiple linear regression of SNOTEL data, postcedent precipitation, and land‐cover changes explained 2%–18% more variability in streamflow prediction than using SNOTEL station data alone. Simulated basin‐wide snowpack from a physically based model had significant...
Categories: Publication; Types: Citation
Seasonal snowpack chemistry data from the Rocky Mountain region of the US was examined to identify long-term trends in concentration and chemical deposition in snow and in snow-water equivalent. For the period 1993–2004, comparisons of trends were made between 54 Rocky Mountain Snowpack sites and 16 National Atmospheric Deposition Program wetfall sites located nearby in the region. The region was divided into three subregions: Northern, Central, and Southern. A non-parametric correlation method known as the Regional Kendall Test was used. This technique collectively computed the slope, direction, and probability of trend for several sites at once in each of the Northern, Central, and Southern Rockies subregions....
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A better understanding of how hydrological and biogeochemical processes control dissolved organic carbon (DOC) concentrations and dissolved organic matter (DOM) composition from headwaters downstream to large rivers is needed. We examined a large DOM dataset from the National Water Information System of the U.S. Geological Survey, which represents approximately 100,000 measurements of DOC concentration and DOM composition at many sites along rivers across the United States. Application of quantile regression revealed a tendency towards downstream spatial and temporal homogenization of DOC concentrations and a shift from dominance of aromatic DOM in headwaters to more aliphatic DOM downstream. The DOC concentration...
Categories: Publication; Types: Citation


map background search result map search result map Headwater C fluxes SnowModel simulations and supporting observations for the north-central Colorado Rocky Mountains during water years 2011 through 2015 Climatological data for the Loch Vale watershed in Rocky Mountain National Park, Colorado, water years 1992-2019 Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011-19 Wetland Stream Water Quality Data for West Twin Creek, AK, Allequash Creek, WI, and Big Thompson River, CO, 2010-2020 Seasonal Atmospheric Nitrate and Ammonium Deposition along an Elevation Gradient in the Colorado Front Range using Ion Exchange Resin Columns (2018-2019) Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011—19 (ver. 2.0, January 2022) Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011 - 19 (ver. 3.0, October 2023) Climatological data for the Loch Vale watershed in Rocky Mountain National Park, Colorado, water years 1992-2019 Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011-19 Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011—19 (ver. 2.0, January 2022) Continuous water-quality data for selected streams in Rocky Mountain National Park, Colorado, water years 2011 - 19 (ver. 3.0, October 2023) Headwater C fluxes Seasonal Atmospheric Nitrate and Ammonium Deposition along an Elevation Gradient in the Colorado Front Range using Ion Exchange Resin Columns (2018-2019) SnowModel simulations and supporting observations for the north-central Colorado Rocky Mountains during water years 2011 through 2015 Wetland Stream Water Quality Data for West Twin Creek, AK, Allequash Creek, WI, and Big Thompson River, CO, 2010-2020