Application of MM5-CAMx-PSAT Modeling Approach for Investigating Emission Source Contribution to Atmospheric SO_𝟐 Pollution in Tangshan, Northern China

Table 1

PCA results for meteorological variables in four selected months in 2006.

PC	Eigenvalue	Proportion variance	Cumulative proportion	Variable	Principal component loadings
					PC1	PC2	PC3	PC4
(a) January
PC1	1.492	0.371	0.371	PBLH	−0.503	0.421	−0.209	0.000
PC2	1.279	0.273	0.644	T2m	0.326	0.598	0.000	−0.26
PC3	1.022	0.174	0.818	WS10	−0.411	0.529	−0.132	0.28
PC4	0.772	0.099	0.918	PSLV	−0.391	−0.405	−0.488	0.21
PC5	0.554	0.051	0.969	RH	0.479	0.147	−0.244	0.799
PC6	0.433	0.031	1.000	WD	−0.297	0.000	0.801	0.412
(b) April
PC1	1.516	0.383	0.383	PBLH	0.574	0.207	−0.143	0.000
PC2	1.280	0.273	0.656	T2m	−0.106	0.715	−0.215	0.000
PC3	0.982	0.161	0.817	WS10	0.318	0.171	0.723	−0.56
PC4	0.813	0.110	0.927	PSLV	0.294	−0.603	−0.305	−0.23
PC5	0.523	0.046	0.973	RH	−0.515	−0.22	0.453	0.227
PC6	0.405	0.027	1.000	WD	0.455	0.000	0.336	0.758
(c) July
PC1	1.435	0.343	0.343	PBLH	0.603	−0.242	0.000	−0.141
PC2	1.182	0.233	0.576	T2m	0.484	0.337	−0.207	−0.465
PC3	1.056	0.186	0.762	WS10	−0.137	−0.171	−0.832	−0.33
PC4	0.785	0.103	0.865	PSLV	−0.279	−0.497	0.404	−0.71
PC5	0.729	0.089	0.953	RH	0.549	0.255	−0.188	0.000
PC6	0.529	0.047	1.000	WD	0.000	−0.698	−0.257	0.381
(d) October
PC1	1.535	0.392	0.392	PBLH	−0.134	0.684	−0.127	0.000
PC2	1.324	0.292	0.685	T2m	0.52	0.301	0.397	0.000
PC3	0.951	0.151	0.835	WS10	−0.226	0.649	−0.132	0.000
PC4	0.785	0.103	0.938	PSLV	−0.576	−0.138	−0.352	−0.13
PC5	0.498	0.041	0.979	RH	0.376	0.000	−0.696	0.607
PC6	0.351	0.021	1.000	WD	−0.433	0.000	0.448	0.781