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*** Atmospheric CO2 concentrations (ppmv) derived from flask air   ***
*** samples collected at Shetland Island, Scotland                 ***
*** Source: L.P. Steele                                            ***
***              P.B. Krummel                                      ***  
***              R. L. Langenfelds,                                ***
***              Atmospheric, Research, Commonwealth Scientific,   ***
***              And Industrial Research Organisation,             ***
***              Aspendale, Victoria,                              *** 
***              Australia  3195                                   ***                   
***                                                                ***   
*** August 2007                                                    ***
***                                                                ***
**********************************************************************

Month	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Ann. Ave
1992												358.84	
1993	359.28	360.38	361.85	361.83	361.65	359.37	351.38	346.77	349.13	353.27	357.30	360.45	356.89
1994	361.94	362.12	363.09	363.15	361.73	359.34	353.87	349.21	350.52	356.17	360.35	361.92	358.62
1995	363.56	364.19	364.70	365.22	364.33	360.93	355.28	351.92	353.75	358.05	361.33	363.79	360.59
1996	365.58	365.74	366.03	366.59	366.07	364.11	358.93	353.84	355.11	360.11	363.96	366.31	362.70
1997	366.88	366.89	367.87	368.52	368.13	365.03	358.86	354.87	356.48	361.16	365.48	367.76	363.99
1998	368.73	369.14	369.70	369.57	369.08	367.32	360.77	356.37	359.93	364.89	367.49	369.78	366.06
1999	371.79	372.09	372.22	372.54	371.65	369.07	363.62	359.51	361.75	365.75	368.68	371.07	368.31
2000	372.18	372.72	373.34	373.25	372.23	370.38	365.36	359.90	360.90	365.58	370.29	373.47	369.13
2001	374.22	374.87	375.93	376.02	374.59	371.79	366.35	361.31	362.83	367.77	371.54	374.40	370.97
2002	375.81	376.33	377.32	377.87	376.79	373.36	367.39	361.83	362.71	369.00	373.64	376.06	372.34
2003	377.34	377.92	380.77	382.79	379.62	375.25	370.35	366.60	368.54	373.26	377.39		

Monthly values are expressed in parts per million (ppm) and reported in the WMO CO2 
Mole Fraction Scale (Zhao et al., 1997, J. Geophys. Res. 102 , 5885-5894). Calibration 
details are discussed by Francey et al. (2003).  Monthly values are calculated as the 
mean of the daily values from a smooth curve fit to the data using 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.