These data files associated with the Tables and Figures presented in the following manuscript: Zhang, Y., Mathur, R., Bash, J. O., Hogrefe, C., Xing, J., and Roselle, S. J.: Long-term trends in total inorganic nitrogen and sulfur deposition in the US from 1990 to 2010, Atmos. Chem. Phys., 18, 9091-9106, https://doi.org/10.5194/acp-18-9091-2018, 2018. This dataset is associated with the following publication: Zhang, Y., R. Mathur, J. Bash, C. Hogrefe, J. Xing, and S. Roselle. Long-term trends in total inorganic nitrogen and sulfur deposition in the US from 1990 to 2010. Atmospheric Chemistry and Physics. Copernicus Publications, Katlenburg-Lindau, GERMANY, 18: 9091-9106, (2018).

This data includes gridded estimates of: (1) decadally averaged total N and S deposition for the conterminous US from 1800-2025, (2) critical loads from the National Critical Loads Database, and (3) exceedances of critical loads from atmospheric deposition of N and/or S. This dataset is associated with the following publication: Clark, C., J. Phelan, P. Doraiswamy, J. Buckley, J. Cajka, R. Dennis , J. Lynch, C. Nolte, and T. Spero. Atmospheric Deposition and Exceedances of Critical Loads from 1800-2025 for the Coterminous United States. BULLETIN OF THE ECOLOGICAL SOCIETY OF AMERICA. Ecological Society of America, Ithaca, NY, USA, 978-1002, (2018).

This asset includes compliance data (registrations and reports), including reports related to reformulated gasoline and conventional gasoline (anti-dumping), gasoline sulfur, mobile source air toxics (including gasoline benzene), sulfur content of on-road and non-road diesel fuel, and renewable fuels under 40 CFR Part 80; and includes registration and compositional information related to fuels and fuel additives under 40 CFR Part 79.

Mid infrared absorption spectra of sulfuric acid (H2SO4), sulfur trioxide (SO3), sulfur dioxide (SO2), and water (H2O) were collected in a high temperature gas cell operating at either 300C or 350C. The spectra were collected using tunable external cavity quantum cascade lasers (ECQCLs) tuning, which were capable of operating over the wavelength range from approximately 7 microns to 9 microns, where H2SO4 and SO3 have their strongest absorption features. The spectra can be used as a library for developing gas sensors.

These data describe the chromatography characteristics of the MARGA instrument software as compared to an alternative, independent technique for chromatogram processing, including an assessment of accuracy, precision and method detection limit. This dataset is associated with the following publication: Chen, X., J. Walker, and C. Geron. Chromatography related performance of the Monitor for Aerosols and Gases in Ambient Air (MARGA): laboratory and field based evaluation. Atmospheric Measurement Techniques. Copernicus Publications, Katlenburg-Lindau, GERMANY, 10(3893): 3908, (2017).

Table summarizes instrument precision assessed by collocating the two sample boxes. Precision is quantified as the standard deviation of the residuals of an orthogonal least squares regression of concentrations from the two sample boxes. This allows for an estimation of gradient precision and ultimately gradient and flux detection limits. This dataset is associated with the following publication: Rumsey, I. Application of an online ion chromatography-based instrument for gradient flux measurements of speciated nitrogen and sulfur. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 9(6): 2581-2592, (2016).

A data delivery application that provides web-based access to of soil, water, climate, land management, and geospatial data produced by Conservation Effects Assessment Project (CEAP) watershed research sites across the United States. Data access via ArcGIS Server and MS SQL Server Enhanced data searches and summary options in Tools Access to high-resolution imagery in the Map>Table of Contents Enhanced graphing options on the Get Data page Transparency sliders for individual map components in the Map>Table of Contents

Datasets describing bulk and speciated water soluble organic nitrogen and carbon species in 24 hour high volume PM samples. This dataset is associated with the following publication: Chen, X., X. Mingjie, M. Hays, E. Eric, D. Schwede, and J. Walker. Characterization of organic nitrogen in aerosols at a forest site in the southern Appalachian Mountains May 2018. Atmospheric Chemistry and Physics. Copernicus Publications, Katlenburg-Lindau, GERMANY, issue}: 6829-6846, (2018).