Table 1. Global XCO2 Variability at 1:00 PM Local Time for a Representative Day in Each Month of the Year 2000 From CASA/MATCH Model Runs

Month	Correlation Length (3L), km	Variance (2sigma2), ppm2
January	2900	0.89
February	5100	1.08
March	5400	1.16
April	4900	1.45
May	5500	1.06
June	4300	1.24
July	6100	4.16
August	8300	3.71
September	7500	2.06
October	2800	1.08
November	700	0.98
December	2700	0.67
Annual Mean	4700	1.63