#323 new parameter for atmospheric composition (#333)

* add new atmosperic composition parameter in Code Table 4.2.0.20

* xml,txt files

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Co-authored-by: Enrico Fucile <efucile@wmo.int>

Author: sebvi

GRIB2_CodeFlag_4_2_0_20_CodeTable_en.csv

@@ -18,7 +18,8 @@ Parameter number by product discipline and parameter category,"Product disciplin
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",16,,Mass mixing ratio with respect to dry air,,,kg/kg,Operational
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",17,,Mass mixing ratio with respect to wet air,,,kg/kg,Operational
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",18,,Potential of hydrogen (pH),,,pH,Operational
-Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",19-49,,Reserved,,,,Operational
+Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",19,,Loss rate due to reaction with hydroxyl radical (OH),,,kg kg-1 s-1,Operational
+Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",20-49,,Reserved,,,,Operational
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",50,,Amount in atmosphere,,,mol,Operational
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",51,,Concentration in air,,,mol m-3,Operational
 Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",52,,Volume mixing ratio (fraction in air),,,mol/mol,Operational

txt/CodeFlag.txt

@@ -1142,7 +1142,8 @@ Code table 4.2 - Parameter number by product discipline and parameter category,"
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",16,,Mass mixing ratio with respect to dry air,,,kg/kg,Operational
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",17,,Mass mixing ratio with respect to wet air,,,kg/kg,Operational
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",18,,Potential of hydrogen (pH),,,pH,Operational
-Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",19-49,,Reserved,,,,Operational
+Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",19,,Loss rate due to reaction with hydroxyl radical (OH),,,kg kg-1 s-1,Operational
+Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",20-49,,Reserved,,,,Operational
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",50,,Amount in atmosphere,,,mol,Operational
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",51,,Concentration in air,,,mol m-3,Operational
 Code table 4.2 - Parameter number by product discipline and parameter category,"Product discipline 0 - Meteorological products, parameter category 20: atmospheric chemical constituents",52,,Volume mixing ratio (fraction in air),,,mol/mol,Operational

xml/CodeFlag.xml

@@ -6860,7 +6860,13 @@
 	</GRIB2_CodeFlag_en>
 	<GRIB2_CodeFlag_en>
 		<Title_en>Code table 4.2 - Parameter number by product discipline and parameter category</Title_en>
-		<CodeFlag>19-49</CodeFlag>
+		<CodeFlag>19</CodeFlag>
+		<MeaningParameterDescription_en>Loss rate due to reaction with hydroxyl radical (OH)</MeaningParameterDescription_en>
+		<Status>Operational</Status>
+	</GRIB2_CodeFlag_en>
+	<GRIB2_CodeFlag_en>
+		<Title_en>Code table 4.2 - Parameter number by product discipline and parameter category</Title_en>
+		<CodeFlag>20-49</CodeFlag>
 		<MeaningParameterDescription_en>Reserved</MeaningParameterDescription_en>
 		<Status>Operational</Status>
 	</GRIB2_CodeFlag_en>