Gregory Wetherbee is a Research Chemist for the USGS Water Resources Mission Area.
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U.S. Geological Survey Precipitation Chemistry Quality Assurance Project Data 2019 – 2020
The USGS Precipitation Chemistry Quality Assurance Project (PCQA) operates QA programs to challenge and test the National Atmospheric Deposition Program (NADP) data-collection processes for both the National Trends Network (NTN) and Mercury Deposition Network (MDN). PCQA data are available in separate tables for each quality-assurance program: (1) NTN Interlaboratory-comparison, (2) MDN Interlabor
Data for the U.S. Geological Survey Precipitation Chemistry Quality Assurance Project for the National Atmospheric Deposition Program, 1978-2017
The U.S. Geological Survey has operated the Precipitation Chemistry Quality Assurance (PCQA) Project to evaluate and document the data quality for the National Atmospheric Deposition Program (NADP) for 40 years. The PCQA is primarily focused on data quality for the NADP National Trends Network (NTN) and Mercury Deposition Network (MDN). The PCQA implements programs to evaluate the variability and
Filter Total Items: 36
Nitrogen isotopes indicate vehicle emissions and biomass burning dominate ambient ammonia across Colorado's Front Range urban corridor
Urban ammonia (NH3) emissions contribute to poor local air quality and can be transported to rural landscapes, impacting sensitive ecosystems. The Colorado Front Range urban corridor encompasses the Denver Metropolitan Area, rural farmland/rangeland and montane forest between the city and the Rocky Mountains. Reactive nitrogen emissions from the corridor are partly responsible for increased N depo
Elevated nitrogen deposition to fire-prone forests adjacent to urban and agricultural areas, Colorado front range, USA
As humans increasingly dominate the nitrogen cycle, deposition of reactive nitrogen (Nr) will continue to have adverse consequences for ecosystems. In the Rocky Mountains, Nr deposition remains elevated and has become increasingly dominated by ammonium, despite efforts to reduce emissions. Currently, spatial models of Nr deposition do not fully account for urban and agricultural emissions, sources
Estimating urban air pollution contribution to South Platte River nitrogen loads with National Atmospheric Deposition Program data and SPARROW model
Air pollution is commonly disregarded as a source of nutrient loading to impaired surface waters managed under the Clean Water Act per states’ 303(d) list programs. The contribution of air pollution to 2017–2018 South Platte River nitrogen (N) loads was estimated from the headwaters to the gage at Weldona, Colorado, USA (100 km downstream of Denver), using data from the National Atmospheric Deposi
Trends in precipitation chemistry across the U.S. 1985–2017: Quantifying the benefits from 30 years of Clean Air Act amendment regulation
Acid rain was first recognized in the 1970s in North America and Europe as an atmospheric pollutant that was causing harm to ecosystems. In response, the U.S. Congress enacted Title IV of the Clean Air Act Amendments (CAA) in 1990 to reduce sulfur and nitrogen emissions from fossil fuel burning power plants. This study reports trends in wet-precipitation chemistry in response to emissions reductio
External quality assurance project report for the National Atmospheric Deposition Program’s National Trends Network and Mercury Deposition Network, 2017–18
The U.S. Geological Survey (USGS) Precipitation Chemistry Quality Assurance project (PCQA) operated five distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program’s (NADP) National Trends Network and Mercury Deposition Network during 2017–18. The National Trends Network programs included (1) a field audit program to evaluate sample contamina
A new sampler for the collection and retrieval of dry dust deposition
Atmospheric dust can influence biogeochemical cycles, accelerate snowmelt, and affect air, water quality, and human health. Yet, the bulk of atmospherically transported material remains poorly quantified in terms of total mass fluxes and composition. This lack of information stems in part from the challenges associated with measuring dust deposition. Here we report on the design and efficacy of a
2017 Monitoring and tracking wet nitrogen deposition at Rocky Mountain National Park
The Colorado Department of Public Health and Environment (CDPHE), the National Park Service (NPS), and the U.S. Environmental Protection Agency (EPA) issued the Nitrogen Deposition Reduction Plan (NDRP) in 2007 to address the effects and trends of nitrogen deposition at Rocky Mountain National Park (RMNP). The agencies chose a glidepath approach to reduce wet nitrogen deposition to a level of 1.5
Science needs for continued development of total nitrogen deposition budgets in the United States
The objectives of this white paper are to describe the state of the science with respect to total Nr deposition budgets in North America and the research needed to improve these budgets from both a measurement and modeling standpoint. The document is intended to serve as a plan for TDep research activities but also, more broadly, to provide program managers, natural resource managers, policy make
Inorganic nitrogen wet deposition gradients in the Denver-Boulder metropolitan area and Colorado Front Range – Preliminary implications for Rocky Mountain National Park and interpolated deposition maps
For the first time in the 40-year history of the National Atmospheric Deposition Program / National Trends Network (NADP/NTN), a unique urban-to-rural transect of wet deposition monitoring stations were operated as part of the NTN in 2017 to quantify reactive inorganic nitrogen wet deposition for adjacent urban and rural, montane regions. The transect of NADP stations (sites) was used to collect
It is raining plastic
Atmospheric deposition samples were collected using the National Atmospheric Deposition Program / National Trends Network (NADP/NTN) at 6 sites in the Denver-Boulder urban corridor and 2 adjacent sites in the Colorado Front Range. Weekly wet-only atmospheric deposition samples collected at these sites during winter-summer of 2017 were filtered (0.45 micrometers, polyethersulfone) to obtain partic
External quality assurance project report for the National Atmospheric Deposition Program’s National Trends Network and Mercury Deposition Network, 2015–16
The U.S. Geological Survey Precipitation Chemistry Quality Assurance project operated five distinct programs to provide external quality assurance monitoring for the National Atmospheric Deposition Program’s (NADP) National Trends Network and Mercury Deposition Network during 2015–16. The National Trends Network programs include (1) a field audit program to evaluate sample contamination and stabil
U.S. Geological Survey external quality-assurance project report for the National Atmospheric Deposition Program / National Trends Network and Mercury Deposition Network, 2011-2012
The U.S. Geological Survey operated six distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program (NADP) / National Trends Network (NTN) and Mercury Deposition Network (MDN) during 2011–2012. The field-audit program assessed the effects of onsite exposure, sample handling, and shipping on the chemistry of NTN samples; a system-blank program
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U.S. Geological Survey Precipitation Chemistry Quality Assurance Project Data 2019 – 2020
The USGS Precipitation Chemistry Quality Assurance Project (PCQA) operates QA programs to challenge and test the National Atmospheric Deposition Program (NADP) data-collection processes for both the National Trends Network (NTN) and Mercury Deposition Network (MDN). PCQA data are available in separate tables for each quality-assurance program: (1) NTN Interlaboratory-comparison, (2) MDN InterlaborData for the U.S. Geological Survey Precipitation Chemistry Quality Assurance Project for the National Atmospheric Deposition Program, 1978-2017
The U.S. Geological Survey has operated the Precipitation Chemistry Quality Assurance (PCQA) Project to evaluate and document the data quality for the National Atmospheric Deposition Program (NADP) for 40 years. The PCQA is primarily focused on data quality for the NADP National Trends Network (NTN) and Mercury Deposition Network (MDN). The PCQA implements programs to evaluate the variability and - Publications
Filter Total Items: 36
Nitrogen isotopes indicate vehicle emissions and biomass burning dominate ambient ammonia across Colorado's Front Range urban corridor
Urban ammonia (NH3) emissions contribute to poor local air quality and can be transported to rural landscapes, impacting sensitive ecosystems. The Colorado Front Range urban corridor encompasses the Denver Metropolitan Area, rural farmland/rangeland and montane forest between the city and the Rocky Mountains. Reactive nitrogen emissions from the corridor are partly responsible for increased N depoElevated nitrogen deposition to fire-prone forests adjacent to urban and agricultural areas, Colorado front range, USA
As humans increasingly dominate the nitrogen cycle, deposition of reactive nitrogen (Nr) will continue to have adverse consequences for ecosystems. In the Rocky Mountains, Nr deposition remains elevated and has become increasingly dominated by ammonium, despite efforts to reduce emissions. Currently, spatial models of Nr deposition do not fully account for urban and agricultural emissions, sourcesEstimating urban air pollution contribution to South Platte River nitrogen loads with National Atmospheric Deposition Program data and SPARROW model
Air pollution is commonly disregarded as a source of nutrient loading to impaired surface waters managed under the Clean Water Act per states’ 303(d) list programs. The contribution of air pollution to 2017–2018 South Platte River nitrogen (N) loads was estimated from the headwaters to the gage at Weldona, Colorado, USA (100 km downstream of Denver), using data from the National Atmospheric DeposiTrends in precipitation chemistry across the U.S. 1985–2017: Quantifying the benefits from 30 years of Clean Air Act amendment regulation
Acid rain was first recognized in the 1970s in North America and Europe as an atmospheric pollutant that was causing harm to ecosystems. In response, the U.S. Congress enacted Title IV of the Clean Air Act Amendments (CAA) in 1990 to reduce sulfur and nitrogen emissions from fossil fuel burning power plants. This study reports trends in wet-precipitation chemistry in response to emissions reductioExternal quality assurance project report for the National Atmospheric Deposition Program’s National Trends Network and Mercury Deposition Network, 2017–18
The U.S. Geological Survey (USGS) Precipitation Chemistry Quality Assurance project (PCQA) operated five distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program’s (NADP) National Trends Network and Mercury Deposition Network during 2017–18. The National Trends Network programs included (1) a field audit program to evaluate sample contaminaA new sampler for the collection and retrieval of dry dust deposition
Atmospheric dust can influence biogeochemical cycles, accelerate snowmelt, and affect air, water quality, and human health. Yet, the bulk of atmospherically transported material remains poorly quantified in terms of total mass fluxes and composition. This lack of information stems in part from the challenges associated with measuring dust deposition. Here we report on the design and efficacy of a2017 Monitoring and tracking wet nitrogen deposition at Rocky Mountain National Park
The Colorado Department of Public Health and Environment (CDPHE), the National Park Service (NPS), and the U.S. Environmental Protection Agency (EPA) issued the Nitrogen Deposition Reduction Plan (NDRP) in 2007 to address the effects and trends of nitrogen deposition at Rocky Mountain National Park (RMNP). The agencies chose a glidepath approach to reduce wet nitrogen deposition to a level of 1.5Science needs for continued development of total nitrogen deposition budgets in the United States
The objectives of this white paper are to describe the state of the science with respect to total Nr deposition budgets in North America and the research needed to improve these budgets from both a measurement and modeling standpoint. The document is intended to serve as a plan for TDep research activities but also, more broadly, to provide program managers, natural resource managers, policy makeInorganic nitrogen wet deposition gradients in the Denver-Boulder metropolitan area and Colorado Front Range – Preliminary implications for Rocky Mountain National Park and interpolated deposition maps
For the first time in the 40-year history of the National Atmospheric Deposition Program / National Trends Network (NADP/NTN), a unique urban-to-rural transect of wet deposition monitoring stations were operated as part of the NTN in 2017 to quantify reactive inorganic nitrogen wet deposition for adjacent urban and rural, montane regions. The transect of NADP stations (sites) was used to collectIt is raining plastic
Atmospheric deposition samples were collected using the National Atmospheric Deposition Program / National Trends Network (NADP/NTN) at 6 sites in the Denver-Boulder urban corridor and 2 adjacent sites in the Colorado Front Range. Weekly wet-only atmospheric deposition samples collected at these sites during winter-summer of 2017 were filtered (0.45 micrometers, polyethersulfone) to obtain particExternal quality assurance project report for the National Atmospheric Deposition Program’s National Trends Network and Mercury Deposition Network, 2015–16
The U.S. Geological Survey Precipitation Chemistry Quality Assurance project operated five distinct programs to provide external quality assurance monitoring for the National Atmospheric Deposition Program’s (NADP) National Trends Network and Mercury Deposition Network during 2015–16. The National Trends Network programs include (1) a field audit program to evaluate sample contamination and stabilU.S. Geological Survey external quality-assurance project report for the National Atmospheric Deposition Program / National Trends Network and Mercury Deposition Network, 2011-2012
The U.S. Geological Survey operated six distinct programs to provide external quality-assurance monitoring for the National Atmospheric Deposition Program (NADP) / National Trends Network (NTN) and Mercury Deposition Network (MDN) during 2011–2012. The field-audit program assessed the effects of onsite exposure, sample handling, and shipping on the chemistry of NTN samples; a system-blank program - News