Supplementary Material 15-Year PM2.5 Trends in the Pearl River Delta Region and Hong Kong from Satellite Observation C.Q. Lin 1,2, Y. Li 3, A.K.H. Lau 1,2,4,*, C.C. Li 5, J.C.H. Fung 2,4,6 * Corresponding author. Tel: (852) 2358 6944; Fax: (852) 2358 1534 E-mail address: [email protected] This file includes: Pages: 1-9 Figures: S1-S6 Tables: S1-S2 1 List of Table Titles and Figure Captions Table S1. Mean PM2.5 trends for the entire PRD region and different cities during the three FYP th periods. Cities are ordered by PM2.5 concentration trends during the 12 FYP period. Table S2. Mean PM2.5 concentration trends for the districts in Hong Kong during the three FYP th periods. Districts are ordered by PM2.5 concentration trends during the 12 FYP period. Figure S1. The left panel shows the topography and the cities in the PRD region: the capital Guangzhou (GZ), the special economic zones of Shenzhen (SZ) and Zhuhai (ZH), Dongguan (DG), Fushan (FS), Zhongshan (ZS), Zhaoqing (ZQ), Jiangmen (JM), and Huizhou (HZ), and the two special administrative regions of Hong Kong (HK) and Macau (MC). The right panel shows the topography and the 18 districts in Hong Kong: North (NO), Yuen Long (YL), Tai Po (TP), Tuen Mun (TM), Tsuen Wan (TW), Sha Tin (ST), Sai Kung (SK), Kwai Tsing (KI), Sham Shui Po (SS), Yau Tsim Mong (YT), Kowloon City (KC), Wong Tai Sin (WT), Kwun Tong (KU), Central and Western (CW), Wan Chai (WC), Eastern (EA), Southern (SO), and Islands (IS). Figure S2. Inter-annual variations of the satellite-derived and ground-observed PM2.5 concentrations in the PRD region from 2001 to 2015. Figure S3. Inter-annual variations of the satellite-derived and ground-observed PM2.5 concentration in Hong Kong from 2001 to 2015. Figure S4. Evaluation of the annual mean of the satellite-derived PM2.5 concentration against ground observations in the PRD region from 2001 to 2015. Figure S5. Evaluation of the monthly mean of the satellite-derived PM2.5 concentration against ground observations in the PRD region from 2001 to 2015. Figure S6. Spatial distributions of the 15-year means of the satellite-derived PM2.5 concentration in the PRD region at resolutions of (a) 1 km and (b) 10 km. 2 Figure S1. The left panel shows the topography and the cities in the PRD region: the capital Guangzhou (GZ), the special economic zones of Shenzhen (SZ) and Zhuhai (ZH), Dongguan (DG), Fushan (FS), Zhongshan (ZS), Zhaoqing (ZQ), Jiangmen (JM), and Huizhou (HZ), and the two special administrative regions of Hong Kong (HK) and Macau (MC). The right panel shows the topography and the 18 districts in Hong Kong: North (NO), Yuen Long (YL), Tai Po (TP), Tuen Mun (TM), Tsuen Wan (TW), Sha Tin (ST), Sai Kung (SK), Kwai Tsing (KI), Sham Shui Po (SS), Yau Tsim Mong (YT), Kowloon City (KC), Wong Tai Sin (WT), Kwun Tong (KU), Central and Western (CW), Wan Chai (WC), Eastern (EA), Southern (SO), and Islands (IS). 3 Figure S2. Inter-annual variations of the satellite-derived and ground-observed PM2.5 concentrations in the PRD region from 2001 to 2015. 4 Figure S3. Inter-annual variations of the satellite-derived and ground-observed PM2.5 concentration in Hong Kong from 2001 to 2015. 5 Figure S4. Evaluation of the annual mean of the satellite-derived PM2.5 concentration against ground observations in the PRD region from 2001 to 2015. Figure S5. Evaluation of the monthly mean of the satellite-derived PM2.5 concentration against ground observations in the PRD region from 2001 to 2015. 6 (a) (b) Figure S6. Spatial distributions of the 15-year means of the satellite-derived PM2.5 concentration in the PRD region at resolutions of (a) 1 km and (b) 10 km. 7 Table S1. Mean PM2.5 trends for the entire PRD region and different cities during the three FYP th periods. Cities are ordered by PM2.5 concentration trends during the 12 FYP period. Region Trend in the 10th FYP Trend in the 11th FYP Trend in the 12th FYP (µg·m-3·yr-1) (µg·m-3·yr-1) (µg·m-3·yr-1) PRD 1.31 -1.54 -2.36 HZ 0.79 -1.89 -1.26 HK 0.92 -0.81 -1.64 SZ 1.32 -0.73 -1.78 DG 1.63 -0.81 -2.38 GZ 2.07 -1.87 -2.48 JM 1.29 -1.61 -2.60 MC -0.08 -0.41 -2.68 ZQ 0.96 -1.35 -2.72 FS 2.75 -2.23 -2.79 ZH 0.32 -0.53 -3.38 ZS 1.15 -0.95 -3.68 8 Table S2. Mean PM2.5 concentration trends for the districts in Hong Kong during the three FYP th periods. Districts are ordered by PM2.5 concentration trends during the 12 FYP period. District Trend in the 10th FYP Trend in the 11th FYP Trend in the 12th FYP (µg·m-3·yr-1) (µg·m-3·yr-1) (µg·m-3·yr-1) SO 0.23 -0.34 -1.13 SK 0.51 -0.88 -1.19 TP 1.01 -0.97 -1.33 EA 0.33 -0.53 -1.34 NO 1.34 -1.02 -1.52 WC 0.40 -0.57 -1.53 KU 0.56 -0.76 -1.61 KC 0.70 -0.78 -1.68 CW 0.48 -0.54 -1.70 YT 0.57 -0.74 -1.70 WT 0.86 -0.75 -1.72 ST 0.85 -0.75 -1.72 IS 0.94 -0.55 -1.79 SS 0.94 -0.74 -1.84 TW 1.05 -0.87 -1.87 KI 1.04 -0.85 -1.93 YL 1.31 -0.91 -2.05 TM 1.36 -0.93 -2.65 9 .