**********************************************************************
*** Atmospheric H2 concentrations (ppbv) derived from flask       ***
*** samples collected at Cape Grim, Australia                      ***
*** Source: L.P. Steele                                            ***
***              P.B. Krummel                                      ***  
***              R.L. Langenfelds                                  ***
***              Commonwealth Scientific,                          ***
***              and Industrial Research Organisation,             ***
***              Aspendale, Victoria,                              *** 
***              Australia  3195                                   ***                   
***                                                                ***   
*** March  2003                                                    ***
***                                                                ***
**********************************************************************

Year	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Ann. Ave.

1992		527.28	525.13	522.97	519.56	515.34	512.62	510.93	510.89	514.08	517.21	518.25	
1993	521.66	523.46	521.76	519.47	515.31	511.02	509.12	508.27	508.25	510.9	515.71	520.7	515.47
1994	523.59	523.77	522.61	519.51	516.26	513.31	511.45	511.37	512.39	517.34	523.06	527.24	518.49
1995	532.52	534.37	531.4	528.45	525.37	521.45	517.84	516.48	518.83	524.37	529.92	533.34	526.20
1996	535.6	535.97	534.34	531.06	525.76	521.74	520.11	518.88	520.26	523.01	525.44	529.23	526.78
1997	533.09	534.1	531.53	528.98	527.12	522.61	519.15	518.11	518.86	524.1	529.68	532.18	526.63
1998	536.15	538.93	539.06	537.1	532.92	530	528.98	528.5	528.83	532.9	538.05	540.48	534.33
1999	542.7	544.21	542.06	537.99	533.9	528.55	525.79	525.78	527.45	531.89	537.09	539.45	534.74
2000	539.91	541.92	539.99	534.72	530.8	527.14	525.56	524.48	522.87	524.07	528.08	532.07	530.97
2001	534.75	535.2	533.82	532.31	528.8	523.98	520.88	520.09	520.83	524.1	529.25	532.46	528.04

Monthly values are expressed in parts per billion per volume (ppbv) and reported in the CSIRO94 H2 scale. 
Monthly values were calculated as the mean of the daily values from a smooth curve fit to the data using 
the curve-fitting routines described by Thoning et al., 1989 (J. Geophys Res. 94, 8549-8565). Annual 
values are the arithmetic means of the 12 monthly values.