Table S2. Monthly isotopic compositions in precipitation and precipitation amount on Okinawa Island. 								
*Air-temperature and relative humidity data were obtained from Naha meteorological station of Japan Meteorological Angecy. 								
Year (CE)	Month	Precipitation (mm)	d17O (permil vs VSMOW)	d18O(permil vs VSMOW)	dD(permil vs VSMOW)	17xs (per meg)	Air temperature (degree C)	Relative humidity (%)
2011	1	100.2	-1.6082	-3.1126	-0.0849	37	14.9	65
2011	2	158.7	-1.4623	-2.8228	-3.1656	29	17.6	71
2011	3	30.3	-1.7977	-3.4716	-8.6005	37	17.1	63
2011	4	100.1	-2.2156	-4.2563	-24.0331	34	20.4	69
2011	5	289.2	-2.6776	-5.0949	-31.0824	16	23.9	86
2011	6	267	-4.1307	-7.8445	-53.1361	19	27.9	85
2011	7	73.2	-3.597	-6.8331	-45.0835	17	28.9	81
2011	8	472.5	-4.4985	-8.5218	-60.8667	10	28.3	81
2011	9	49.7	-2.0603	-3.9328	-23.5535	18	27.9	76
2011	10	268.6	-2.9279	-5.5821	-33.1863	23	25.2	78
2011	11	338.3	-2.5125	-4.8063	-26.2562	28	23.7	76
2011	12	134.9	-2.8219	-5.4005	-24.9727	33	18.6	69
2012	1	144.2	-1.985	-3.8187	-8.9162	33	17	71
2012	2	110.8	-3.482	-6.628	-38.87	23	17.5	74
2012	3	125.4	-1.3326	-2.5864	-4.6763	34	19.6	71
2012	4	384	-2.2872	-4.3817	-22.9125	29	21.7	75
2012	5	204	-4.0478	-7.6995	-49.4987	25	24.4	77
2012	6	374.9	-3.8383	-7.2885	-49.5094	17	26.9	86
2012	7	72.4	-3.8342	-7.2749	-47.3007	14	29.1	79
2012	8	685.1	-4.181	-7.9275	-54.7396	13	28.5	82
2012	9	298.3	-3.733	-7.0912	-45.7022	18	27.2	76
2012	10	185.2	-4.0604	-7.7245	-48.8821	26	24.6	70
2012	11	203.7	-3.0075	-5.7648	-29.1745	41	21	67
2012	12	49.1	-3.4137	-6.5545	-28.7657	53	18.5	65