------------------------------------------------------------------------------------------------------------------------
This dataset contains the 0.02×0.02 monthly oversampled NH3 dataset for contiguous U.S. in the article "Monthly patterns 
of ammonia over the contiguous United States at 2 km resolution" by Rui Wang, Xuehui Guo, Da Pan, James Kelly, 
Jesse Bash, Kang Sun, Fabien Paulot, Lieven Clarisse, Martin Van Damme, Simon Whitburn, Pierre-François Coheur, 
Cathy Clerbaux, and Mark A. Zondlo (submitted to Geophysical Research Letters)

Contact: Rui Wang (ruiw@princeton.edu), Mark Zondlo (mzondlo@princeton.edu)
This dataset was first published on 2020-12-11.

The dataset contains:
1. 01_CONUS_IASI_v2.2r.nc
2. 02_CONUS_IASI_v2.2r.nc
3. 03_CONUS_IASI_v2.2r.nc
4. 04_CONUS_IASI_v2.2r.nc
5. 05_CONUS_IASI_v2.2r.nc
6. 06_CONUS_IASI_v2.2r.nc
7. 07_CONUS_IASI_v2.2r.nc
8. 08_CONUS_IASI_v2.2r.nc
9. 09_CONUS_IASI_v2.2r.nc
10. 10_CONUS_IASI_v2.2r.nc
11. 11_CONUS_IASI_v2.2r.nc
12. 12_CONUS_IASI_v2.2r.nc
13. CONUS_IASI_v2.2r.kmz
14. CONUS_IASI_v2.2r_95th_boundary.kmz
15. CONUS_IASI_v2.2r_animation.gif
16. README.txt

------------------------------------------------------File 1 - 12-------------------------------------------------------
File 1 - 12 are netCDF files for each month's oversampled NH3 data. For each file, there are three variables:
lat: latitude, unit: degree
lon: longitude, unit: degree
NH3: NH3 column, unit: molec/cm2. Missing data were indicated by NaN.

------------------------------------------------------File 13-----------------------------------------------------------
kmz file for annual averaged NH3 in the contiguous U.S.

------------------------------------------------------File 14-----------------------------------------------------------
kmz file for the NH3 hotspots boundary in the contiguous U.S. NH3 column abundances larger than the 95% percentile 
(6.6 × 10^15 molec/cm2) of the 10-year averaged level 3 map are defined as “hotspot” regions. 

------------------------------------------------------File 15-----------------------------------------------------------
Animation for the monthly oversampled NH3 maps in the contiguous U.S.


----------------------------------------------------Methodology---------------------------------------------------------
The the Infrared Atmospheric Sounding Interferometer (IASI) v2.2R retrieval product data (2008-2017) were obtained from 
the MetOp/A (2008-current) and MetOp/B (2013-current) satellites (limited to cloud fraction ≤10%). The details of the 
oversampling algorithm is described in the article "A physics-based approach to oversample multi-satellite, multispecies 
observations to a common grid" by Kang Sun, Lei Zhu, Karen Cady-Pereira, Christopher Chan Miller, Kelly Chance, 
Lieven Clarisse, Pierre-François Coheur, Gonzalo González Abad, Guanyu Huang, Xiong Liu, Martin Van Damme, Kai Yang, 
and Mark Zondlo

----------------------------------------------------Funding info--------------------------------------------------------
We acknowledge support from the NASA Health and Air Quality Applied Sciences team (NASA NNX16AQ90G).