README -- Describes contents of HEMCO/MASKS/v2014-07 directory
24 Jan 2023
GEOS-Chem Support Team
geos-chem-support@g.harvard.edu


Overview:
===============================================================================

This directory contains the various mask files needed for certain regional
emissions inventories.


Files:
===============================================================================

All mask files have units of "1" (aka "unitless") unless otherwise specified.

AF_LANDMASK.geos.05x0666.nc

 -- Mask file for use with the DICE Africa emissions
    Resolution  : GEOS-Chem 0.5 x 0.666 grid (112 x 155 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/112,lat/155,time/1

AF_LANDMASK.geos.05x0666.global.nc

 -- Mask file for use with the DICE Africa emissions in GCHP which requires
    global bounds in the file
    Resolution  : GEOS-Chem 0.5 x 0.666 grid (361 x 540 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/540,lat/361,time/1

Canada_Mask.Extended_NAgrid.01x01.nc
Canada_Mask_Mirror.Extended_NAgrid.001x001.nc

 -- Mask file (and its mirror-image) for Canada for use with the 
    Canadian oil/gas CH4 emissions  from Sheng et al. (2017)
    Resolution  : GENERIC 0.01 x 0.01 grid
    Timestamp   : 2016/01 
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/10100,lat/7500

CONUS_Mask.001x001.nc
CONUS_Mask_Mirror.001x001.nc

 -- Mask file (and its mirror-image) for contiguous US for use with
    the gridded EPA CH4 emissions from Maasakkers et al.(2016)
    Resolution  : GENERIC 0.01 x 0.01 grid
    Timestamp   : 2016/01 
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/7000,lat/3500

countrymask_0.1x0.1.nc

 -- Mask file for applying country-specific scale factors
    Resolution  : GENERIC 0.1 x 0.1 grid (3600 x 1800 boxes)
    Timestamps  : 2000/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/3600,lat/1800,time/1
    Source      : Shapefile from GADM database (www.gadm.org)

EU_mask.generic.1x1.nc

 -- Mask file for use with the mercury European emissions
    Resolution  : GENERIC 1 x 1 grid (360 x 180 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/180,time/1

India_mask.generic.1x1.nc

 -- Mask file for use with the mercury Indian emissions
    Resolution  : GENERIC 1 x 1 grid (360 x 180 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/180,time/1

Mexico_Mask.Extended_NAgrid.01x01.nc

 -- Mask file for Mexico for use with the Mexican oil/gas CH4 emissions
    from Sheng et al. (2017)
    Resolution  : GENERIC 0.01 x 0.01 grid
    Timestamp   : 2016/01 
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/10100,lat/7500

MIX_Asia_mask.generic.025x025.nc

 -- Mask file for use with the MIX Asian emissions
    Resolution  : GENERIC 0.25 x 0.25 grid (1440 x 720 grid boxes)
    Timestamps  : 2008/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/1440,lat/720,time/1

SE_Asia_mask.generic.1x1.nc

 -- Southeast Asia mask file
    Resolution  : GENERIC 1 x 1 grid (360 x 180 boxes)
    Timestamps  : 2000/01/01 00:00 UTC
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/180,time/1

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%      MASK FILES USED WITH INVENTORIES SINCE RETIRED FROM GEOS-Chem     %%%
%%%              We will keep these files here for reference               %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

BRAVO.MexicoMask.generic.1x1.nc

 -- Mask file for use with the BRAVO Mexican emissions
    Resolution  : GENERIC 1 x 1 grid (360 x 180 boxes)
    Timestamp   : 1999/01 
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/180,time/1

Canada_mask.geos.1x1.nc

 -- Mask file for use with the CAC Canadian emissions
    Resolution  : GENERIC 1 x 1 grid (360 x 180 boxes)
    Timestamp   : 2000/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/180,time/1

EMEP_mask.geos.1x1.20151222.nc

 -- Mask file for use with the EMEP European emissions
    Resolution  : GEOS-Chem 1 x 1 grid (360 x 181 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/360,lat/181,time/1

    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %%% NOTE: THIS MASK FILE FIXES A PROBLEM REPORTED BY ELOISE MARAIS:    %%%
    %%%                                                                    %%%
    %%% Anthropogenic emissions are zero where the EMEP and EDGAR          %%%
    %%% emissions coincide at 30 degrees North (using GC v10-01).          %%%
    %%% This is because the EMEP mask extends to gridsquares where EMEP    %%%
    %%% emissions are zero. Anthropogenic emissions are relatively low     %%%
    %%% there, so this issue only shows up when NOx emissions are plotted  %%%
    %%% on a log scale.                                                    %%%
    %%%                                                                    %%%
    %%% My quick fix is to shift the minimum latitude of the EMEP mask up  %%%
    %%% by 1 degree latitude (starting at 31 deg N instead of 30 deg N).   %%% 
    %%% This is included in file EMEP_mask.geos.1x1.20151222.nc.           %%%
    %%% The older file EMEP.mask.geos.1x1.nc is now deprecated.            %%% 
    %%%                                                                    %%%
    %%%    -- Added by Bob Yantosca (06 Jan 2016, 20 Apr 2018)             %%%
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

NA_mask.geos.1x1.nc

 -- North American mask file used for the Cooke et al BC/OC emissions
    Resolution  : GEOS-Chem 1 x 1 grid (360 x 181 boxes)
    Timestamps  : 1985/01
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    :  nccopy -c lon/360,lat/181,time/1

USA_LANDMASK_NEI2011_0.1x0.1.20160921.nc

 -- Mask file for use with the NEI2011 emissions.
    Resolution  : REGIONAL 0.1 x 0.1 grid (400 x 900 boxes)
    Timestamps  : 2011/11/01 00:00 UTC
    Units       : 1
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/900,lat/400,time/1

    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    %%% NOTE: THIS MASK FILE FIXES A PROBLEM REPORTED BY                   %%%
    %%% AARON VAN DONKELAAR:                                               %%%
    %%%                                                                    %%% 
    %%% This file fixes a bug that was in USA_LANDMASK_NEI2011_0.1x0.1.nc. %%%
    %%% Aaron Van Donkelaar wrote:                                         %%%
    %%%   "The original NEI2011 mask overwrote regions not covered within  %%%
    %%%    the inventory itself, effectively zeroing all emissions from    %%%
    %%%    any source over a sizeable swath of Northern Canada,            %%%
    %%%    including Alberta’s tarsands, as well as parts of Mexico."      %%%
    %%%                                                                    %%%
    %%% The file USA_LANDMASK_NEI2011_0.1x0.1.nc is now deprecated.        %%%
    %%%                                                                    %%%
    %%%    -- Added by Bob Yantosca (06 Jan 2016, 20 Apr 2018)             %%%
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

USA_NEI2011ek_mask.nc

 -- Mask file for use with the NEI2011ek emissions
    Resolution  : REGIONAL 0.1 x 0.1 grid (400 x 900 boxes)
    Units       : 1
    Compression : Level 1 (e.g. nccopy -d1)
    Chunking    : nccopy -c lon/900,lat/400,time/1


BRAVO.MexicoMask.geos.1x1.nc
Canada_and_USA_mask.geos.1x1.nc
GEOS5.20060101.generic.1x1.nc
GEOS5.4x5.20060101.nc
mx.usa.geos.1x1.nc
sfca.gc.geos.4x5.nc
bravo.geos.1x1.nc
uniform.geos.1x1.nc
uniform.geos.4x5.nc
USA_mask.geos.1x1.nc
usa.can.mask.nei2005.geos.1x1.nc
usa.can.mex.mask.nei2005.geos.1x1.nc
usa.mex.mask.nei2005.geos.1x1.nc
usa_mask.epa_nei_200411.geos.1x1.nc
usa_mask.epa_nei_200411.geos.4x5.nc
usa_mask.epa_nei_200806.geos.1x1.nc
usa_mask.epa_nei_200806.geos.4x5.nc

 -- Other mask files for specific implementations (see comments below)
    or mask files that have become obsolete

###############################################################################
#####                   ORIGINAL README FOLLOWS HERE                      #####
###############################################################################


At the moment, there are several USA masks to be compliant with the former 
version of Geos-Chem, where different masks are applied to the NEI2005 and 
NEI1999 inventory. 

- USA_mask.geos.1x1.nc is the usa mask obtained from 
    /as/data/geos/GEOS_1x1/EPA_NEI_200806/usa_mask.geos.1x1(.bpch). 
  This mask is currently not used.

- usa_mask.epa_nei_200411.gen.1x1.nc and usa_mask.epa_nei_200411.geos.4x5.nc 
  are obtained from 
  /as/data/geos/GEOS_4x5/EPA_NEI_200411/usa_mask.geos.4x5(.bpch). 
  It is applied to NEI99 emissions if BRAVO and CAC inventories are not used.

- usa_mask.epa_nei_200806.gen.1x1.nc is obtained from 
  /as/data/geos/GEOS_4x5/EPA_NEI_200806/usa_mask.geos.4x5(.bpch). 
  It is applied to NEI99 emissions if BRAVO and/or CAC inventories are used.

Note that when using higher resolution masks, more grid boxes may actually be 
considered as compared to the low-resolution masks!