GRACE 'months'

Generation of a good gravity field solution requires accumulation of satellite-to-satellite tracking data for about 1 month. The data we give here are labeled by their nominal month (consecutive since 1/1/2002=1). We list the actual data dates (start, end, and missing) over which data were collected corresponding to the nominal month. Within that month, a few days of data may not be used due to instrument issues. The 'Common' missing days are missing in solutions from all 3 centers; the last 3 columns indicate additional days missing from that center's solutions. Please note there are several missing consecutive weeks due to 'battery management' starting in 2011, occurring approximately every 6 months. In addition, there are certain months during which the GRACE orbit is in a near-repeat pattern. This phenomenon prevents computation of a higher spherical harmonic degree and order solution from the data. Those months are so labelled below.

NOMIN MONTH		YEAR	DAY	YEAR	DAY	COMMON MISSING DAYS	CSR	GFZ	JPL
04	APR	2002	102	2002	120	118		n/a	n/a
05	MAY	2002	121	2002	139			n/a	Used 094-138
08	AUG	2002	213	2002	243	238, 240			Used 209-243
09	SEP	2002	244	2002	273	250,251,252,253,254,255, 256,257,258,270
10	OCT	2002	274	2002	304	281, 282, 283, 284		304
11	NOV	2002	305	2002	334	310, 311, 330
12	DEC	2002	335	2002	365	349
13	JAN	2003	001	2003	031	24, 27, 30		n/a
14	FEB	2003	032	2003	059	39, 57
15	MAR	2003	060	2003	090	65
16	APR	2003	091	2003	120
17	MAY	2003	121	2003	142		142		142
19	JUL	2003	182	2003	212
20	AUG	2003	213	2003	243
21	SEP	2003	244	2003	273	264
22	OCT	2003	274	2003	304
23	NOV	2003	305	2003	334	328
24	DEC	2003	335	2003	365
25	JAN	2004	001	2004	013
26	FEB	2004	035	2004	060
27	MAR	2004	061	2004	091
28	APR	2004	092	2004	121
29	MAY	2004	122	2004	152	145, 146, 147
30	JUN	2004	153	2004	182			153
31	JUL	2004	183	2004	213
32	AUG	2004	214	2004	244	near 4-day repeat orbits
33	SEP	2004	245	2004	274	near 4-day repeat orbits
34	OCT	2004	275	2004	305	near 4-day repeat orbits
35	NOV	2004	306	2004	335	near 4-day repeat orbits
36	DEC	2004	336	2004	366	345, 346, 347
37	JAN	2005	001	2005	031
38	FEB	2005	032	2005	059
39	MAR	2005	060	2005	090	73, 74, 75
40	APR	2005	091	2005	120
41	MAY	2005	121	2005	151
42	JUN	2005	152	2005	181
43	JUL	2005	182	2005	212
44	AUG	2005	213	2005	243
45	SEP	2005	244	2005	273
46	OCT	2005	274	2005	304
47	NOV	2005	305	2005	334			334
48	DEC	2005	335	2005	365	337, 343, 344, 345, 346		335,336, 365
49	JAN	2006	001	2006	031
50	FEB	2006	032	2006	059
51	MAR	2006	060	2006	090	72,85
52	APR	2006	091	2006	120
53	MAY	2006	121	2006	151
54	JUN	2006	152	2006	181	166
55	JUL	2006	182	2006	212
56	AUG	2006	213	2006	243
57	SEP	2006	244	2006	273
58	OCT	2006	274	2006	304
59	NOV	2006	305	2006	334
60	DEC	2006	335	2006	365	358,359,360
61	JAN	2007	001	2007	031	12,13,17,18,19
62	FEB	2007	032	2007	059
63	MAR	2007	060	2007	090
64	APR	2007	091	2007	120
65	MAY	2007	121	2007	151
66	JUN	2007	152	2007	181	164, 165, 166, 167
67	JUL	2007	182	2007	212	205, 206, 207
68	AUG	2007	213	2007	243	216,217,218,221,228,229, 230,231,232
69	SEP	2007	244	2007	273
70	OCT	2007	274	2007	304
71	NOV	2007	305	2007	334	326, 327, 328, 329
72	DEC	2007	335	2007	365
73	JAN	2008	001	2008	031
74	FEB	2008	032	2008	060
75	MAR	2008	061	2008	091
76	APR	2008	092	2008	121	112, 113, 114
77	MAY	2008	122	2008	152
78	JUN	2008	153	2008	182
79	JUL	2008	183	2008	213
80	AUG	2008	214	2008	244
81	SEP	2008	245	2008	274
82	OCT	2008	275	2008	305
83	NOV	2008	306	2008	335
84	DEC	2008	336	2008	366
85	JAN	2009	001	2009	031
86	FEB	2009	032	2009	059
87	MAR	2009	060	2009	090
88	APR	2009	091	2009	120
89	MAY	2009	121	2009	151	121, 122, 123, 124
90	JUN	2009	152	2009	181
91	JUL	2009	182	2009	212
92	AUG	2009	213	2009	243
93	SEP	2009	244	2009	273
94	OCT	2009	274	2009	304
95	NOV	2009	305	2009	334
96	DEC	2009	335	2009	365	near 7-day repeat orbits
97	JAN	2010	001	2010	031
98	FEB	2010	032	2010	059
99	MAR	2010	060	2010	090		77
100	APR	2010	091	2010	120
101	MAY	2010	121	2010	151
102	JUN	2010	152	2010	181
103	JUL	2010	182	2010	212		197
104	AUG	2010	213	2010	243
105	SEP	2010	244	2010	273
106	OCT	2010	274	2010	304
107	NOV	2010	305	2010	334
108	DEC	2010	335	2010	365	363,364, 365	354,355,361,362		362
109	JAN	2011	001	2011	031	001 to 031, battery management
110	FEB	2011	032	2011	059	032 to 037	38		38
111	MAR	2011	060	2011	090
112	APR	2011	091	2011	120		109,110,118
113	MAY	2011	121	2011	151
114	JUN	2011	152	2011	181	152 to 181, battery management
115	JUL	2011	182	2011	212	182,183,184	185,186,187,188		185,186,187
116	AUG	2011	213	2011	243
117	SEP	2011	244	2011	273
118	OCT	2011	274	2011	304
119	NOV	2011	289	2011	320	Battery management. Note overlap with previous			289
120	DEC	2011	346	2012	011	Battery management. Missing 321-345. Note overlap with following	349		353-015 used
121	JAN	2012	001	2012	031
122	FEB	2012	032	2012	060
123	MAR	2012	061	2012	091
124	APR	2012	092	2012	121	110-121
125	MAY	2012	122	2012	152	122-152
126	JUN	2012	153	2012	182
127	JUL	2012	183	2012	213
128	AUG	2012	214	2012	244
129	SEP	2012	245	2012	274	270-274
130	OCT	2012	275	2012	305	275-305
131	NOV	2012	306	2012	335	306-310			311-313
132	DEC	2012	336	2012	366		Unused days: 342,343
133	JAN	2013	001	2013	031
134	FEB	2013	032	2013	059	58,59
135	MAR	2013	060	2013	090		not yet	not yet	not yet