The data sets are outputs from the WRF-CMAQ modeling system. Typically these files contain a number of meteorological and atmospheric pollutant concentrations on a model grid which is either 2- or 3-dimensional and also in some instances vary with time. This dataset is associated with the following publication: Xing, J., R. Mathur , J. Pleim , C. Hogrefe , C. Gan, D. Wong , C. Wei, and J. Wang. Air pollution and climate response to aerosol direct radiative effects: A modeling study of decadal trends across the northern hemisphere. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES. American Geophysical Union, Washington, DC, USA, 120(33): 12221-12236, (2015).

CMAQ and WRF output files. This dataset is not publicly accessible because: Too Big. It can be accessed through the following means: The data can be accesses from the ASM data archive at the National Environmental Supercomputing Center at the USEPA. Format: WRF–CMAQ Model output data including SW radiation, PM2.5 , Sulfate aerosol, EC, and SO2 concentrations, Also aerosol optical depth (AOD). This dataset is associated with the following publication: Gan, C., J. Pleim , R. Mathur , C. Hogrefe , C.N. Long, J. Xing, D. Wong , R. Gilliam , and C. Wei. Assessment of long-term WRF–CMAQ simulations for understanding direct aerosol effects on radiation "brightening" in the United States. Atmospheric Chemistry and Physics. Copernicus Publications, Katlenburg-Lindau, GERMANY, 15: 12193-12209, (2015).

The Atmospheric Infrared Sounder (AIRS) is a grating spectrometer (R = 1200) aboard the second Earth Observing System (EOS) polar-orbiting platform, EOS Aqua. This precipitation estimate from AIRS IR only is using a TOVS-like algorithm, and is intended for merging into the precipitation product of the Global Precipitation Climatology Project (GPCP). The precipitation estimate from AIRS Level 2 Support product, which are 6-min swath granules (240 per day) are combined here into one daily "Level 2G" global grid with dimensions (24x1440x720). Thus every hour is a "layer", and the resulting grid cell size is 0.25 degree (~25 km). Thus the grid size is made to fit TRMM products. Since AIRS precipitation is retrieved at AMSU footprint resolution, which is about 45 km at nadir, many grid cells in this 0.25-deg grid are "empty". The data are stored such that the first line is the South Pole. The geolocation information for every hour-layer is also provided in the file.

The dataset represents the data depicted in the Figures and Tables of a Journal Manuscript with the following abstract: "The objective of this study is to determine the adequacy of using a relatively coarse horizontal resolution (i.e. 36 km) to simulate long-term trends of pollutant concentrations and radiation variables with the coupled WRF-CMAQ model. WRF-CMAQ simulations over the continental United State are performed over the 2001 to 2010 time period at two different horizontal resolutions of 12 and 36 km. Both simulations used the same emission inventory and model configurations. Model results are compared both in space and time to assess the potential weaknesses and strengths of using coarse resolution in long-term air quality applications. The results show that the 36 km and 12 km simulations are comparable in terms of trends analysis for both pollutant concentrations and radiation variables. The advantage of using the coarser 36 km resolution is a significant reduction of computational cost, time and storage requirement which are key considerations when performing multiple years of simulations for trend analysis. However, if such simulations are to be used for local air quality analysis, finer horizontal resolution may be beneficial since it can provide information on local gradients. In particular, divergences between the two simulations are noticeable in urban, complex terrain and coastal regions.". This dataset is associated with the following publication: Gan , M., C. Hogrefe , R. Mathur , J. Pleim , J. Xing , D. Wong , R. Gilliam , G. Pouliot , and C. Wei. Assessment of the effects of horizontal grid resolution on long-term air quality trends using coupled WRF-CMAQ simulations. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, USA, 132: 207-216, (2016).

The GRIP Langley Aerosol Research Group Experiment (LARGE) dataset was collected by the Langley Aerosol Research Group Experiment (LARGE), which measures ultrafine aerosol number density, total and non-volatile aerosol number density, dry aerosol size distribution, total and submicron aerosol absorption coefficients, total and submicron aerosol scattering coefficients, and total scattering and hemispheric backscattering coefficients. Instruments used during LARGE derived aerosol size statistics (mode, number and mass mean diameters, etc.), aerosol surface area and mass loading, aerosol extinction, single scattering albedo, and angstrom coefficients. This dataset was collected during the Genesis and Rapid Intensification Processes (GRIP) experiment, which a NASA Earth science field experiment. The major goal was to better understand how tropical storms form and develop into major hurricanes. NASA used the DC-8 aircraft, the WB-57 aircraft and the Global Hawk Unmanned Airborne System (UAS), configured with a suite of in situ and remote sensing instruments that were used to observe and characterize the lifecycle of hurricanes. The GRIP LARGE dataset collected data over the Gulf of Mexico from August 6, 2010 to September 22, 2010.

**Overview** The available "readme" file introduces the basics of the Doppler lidar data and offers a detailed description of the variables present in the data files. For those with any further questions about the data and its interpretation, contact either Alan Brewer () or Sunil Baidar (). It is highly recommended to discuss any planned use of the data with National Oceanic and Atmospheric Administration-Chemical Sciences Division (NOAA-CSD) scientists. For more information, refer to the Readme file: "noaa-esrl-arlingtonlidar-readme-1.pdf." **Data Quality** Refer to the attached "noaa-esrl-arlingtonlidar-readme-1.pdf" Readme file. **Uncertainty** Refer to the attached "noaa-esrl-arlingtonlidar-readme-1.pdf" Readme file. **Constraints** Refer to the attached "noaa-esrl-arlingtonlidar-readme-1.pdf" Readme file.

GLAH10 Level-2 aerosol vertical structure data contain the attenuation-corrected cloud and aerosol backscatter and extinction profiles at a 4 sec sampling rate for aerosols and a 1 sec rate for clouds. Each data granule has an associated browse product.

Model output from the 2-way coupled WRF-CMAQ modeling system applied to China. This dataset is not publicly accessible because: EPA scientists helped with the model set-up and data analysis. The data was created by collaborators at Tsinghua University and is housed there. Since its not EPA generated data, the dataset is not included in ScienceHub. It can be accessed through the following means: The data can be accessed by contacting the corresponding author Prof. Shuxiao Wang (email: shxwang@tsinghua.edu.cn; phone: +86-10-62771466; fax: +86-10-62773650). Format: The data analyzed in this study were created by collaborators at Tsinghua University, China. The data can be accessed by contacting the corresponding author Prof. Shuxiao Wang (email: shxwang@tsinghua.edu.cn; phone: +86-10-62771466; fax: +86-10-62773650). This dataset is associated with the following publication: Xing, J., J. Wang, R. Mathur, S. Wang, G. Sarwar, J. Pleim, C. Hogrefe, Y. Zhang, J. Jiang, D. Wong, and J. Hao. Impacts of aerosol direct effects on tropospheric ozone through changes in atmospheric dynamics and photolysis rates. Atmospheric Chemistry and Physics. Copernicus Publications, Katlenburg-Lindau, GERMANY, 17: 9869-9883, (2017).