## 2 SAR Data, Field Data and Study Sites
### Field Observations for Calibration of the Rice Detection Algorithm and Map Validation
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Site** & **Country,** & **Season** & **Period** & **Number of** & **Crop** & **Variety and Maturity** & **Water** & **Notes** \\
**ID** & **Study Site** & & **Covered** & **Fields, Visits** & **Method** & & **(days)** & **Management** & \\ \hline
**1** & Cambodia, & Dry & October to & 4 fields, & Direct seeding & IR504 (95) & Irrigated & \\  & Takeo & April & 20 visits & & Transplanting & NSIC Rc222 (114) & Irrigated & Typhoon on 8 \\
**2** & Philippines, & & May to & September & 200 visits & Transplanting & NSIC Rc221 (112) & Irrigated & Typhoon on 8 \\  & Leyte East & & May to & 20 fields, & Transplanting & NSIC Rc216 (112), & & November 2013 \\ \hline
**3** & Philippines, & Wet & May to & September & 200 visits & Transplanting & NSIC Rc216 (112), & & \\  & Leyte West & & May to & 200 visits & & NSIC Rc238 (110) & & \\ \hline
**4** & Philippines, & & May to & 18 fields, & Transplanting & PSB Re18 (123), & & Irrigated with \\  & Aguasan del & Dry & October & 182 visits & and direct & NSIC Rc160 (107), & & some rainfed \\  & Norte & & & & seeding & NSIC Rc122 (112) & & \\ \hline
**5** & Vietnam, & Summer– & June to & 12 fields, & Transplanting & OM6976 (100), & & & \\  & Soc Trang & autumn & September & 66 visits & and direct & & ST5 (120), & & \\  & & & September & 66 visits & and direct & OM108-5 (100), & & & \\  & & & & & seeding & OM9584-1 (95), & & & \\ \hline
**6** & Vietnam, & Summer & July to & 20 fields, & & Transplanting & Tap Gao (125), & & \\  & Nam Dinh & Summer & November & 160 visits & & & BC 15 (134) & Irrigated & \\ \hline
**7** & Indonesia, & Wet & November & 20 fields, & & Cisherang, Inpari, & & Early drought \\  & Subang & Wet & to April & 20 fields, & & Meskonga, & & with flood \\  & & & to April & 160 visits & & Sintanur (115), & & event, early \\  & & & & & & Ketan, IR42 (135) & & January 2014 \\ \hline
**8** & India, & & & mid-July to & 20 fields, & & CR1009 (160), & & & \\  & Tamil Nadu, & Cuddalore & & January & 20 fields, & & BPTS204 (135), & & \\  & & & January & 160 visits & & White Ponni (130), & & \\  & & & & & Co 50 (160) & & & \\ \hline
**9** & India, & & & & & & & \\  & Tamil Nadu, & Samba & August to & 20 fields, & & Transplanting & CR1009 (160), & & & \\  & & December & 162 visits & and direct & BPTS204 (135), & & & \\  & Thanjavur & & & & seeding & ADT 50 (160) & & & \\ \hline
**10** & India, & & & September & 18 fields, & Transplanting & & ADT45 (110), & & \\  & Tamil Nadu, & Samba & to January & 110 visits & and direct & & JGL (100–110), & & & \\  & Sivaganga & & & & 110 visits & and direct & & ADT36 (110), & & \\  & & & & & seeding & Jothi (110) & & & \\ \hline
**11** & Thailand, & & May to & 16 fields, & & & KDML105 (\(>\)150), & & & Early drought \\  & Muang Yang & Wet & May to & 130 visits & Direct seeding & RD15 (179), & & & with flood \\  & & & & & & RD6 (178) & & & event, early \\  & & & & & & October 2013 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Summary of site visits and observed rice crop characteristics during the monitored seasons. Field staff conducted multi-day journeys through each footprint, following routes based on local knowledge of the land cover. GPS coordinates, photos and land cover descriptions were collected at each location. These map validation assessments were generally conducted in-season, in the reproductive or ripening stage before harvesting, but in some cases, the assessment was conducted post-season; hence, rice stubble and farmer surveys were used to confirm that the observed post-harvest situation reflected the presence of a rice crop during the monitored season. Locations were chosen such that the land cover was homogeneous in a 15-m radius around each GPS point for sites using 3-m resolution imagery and a 50-m radius for sites using 10-m or 15-m resolution imagery.