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, List of Figure Captions, p.1089

, Figure 1 : Satellite SSS: SMOS SSS corrected according to (a, d, g, j) K2016 methodology, p.1090

, the method described in this paper (CEC); (c, f, i, l) SMAP SSS. 4 case study areas, p.1091

. Bengal-, (d, e, f) : Gulf of Mexico ? August18 th 2015 ; (g, h, i) : Eastern Tropical 1092, 2015.

, Amazon plume SMOS and 1093 SMAP SSS are averaged over respectively a SMOS repetitive orbit sub-cycle (18 days) and two 1094 SMAP repetitive orbit cycles (16 days) Striking fresh SSS features in better agreement with SMOS 1095 (new version) and SMAP are indicated with black arrows, Atlantic Freshwater Pools, 2015.

, latitudinal profiles of mean SSS (a; b) and of the 1097 standard deviation of the 2011-2016 monthly differences between SMOS SSS and ISAS SSS 1098 (c; d) The latitudinal means and standard deviations are computed over the Pacific Ocean 1099 further than 1200 km from any coast: green: ISAS, blue: SMOS ascending orbits; red: SMOS 1100 descending orbits: a;c) November; middle of the swath (0-50 km from the center of the 1101 swath), Figure, vol.2, 2011.

, SSS variability (?SSSnat) derived from 7 years of SMOS filtered and corrected 1104 SSS (after debiasing and filtering): large values are observed in river plumes and in rainy 1105 areas (ITCZ, SPCZ. b) Minimum and c) maximum of the SSS as derived from 18-day CEC 1106 LOCEAN that are used in the mapping of debiased near-real time products (see section 3, Figure, vol.34

, Figure 4: Monthly SMOS SSS compared to monthly ISAS SSS from, 2010.

L. Smos and S. Sss, Standard Number of 1109 months with differences between L3P and L3Q SMOS SSS greater than 0.2pss. d) Frequency with 1110 which corrections identified on Figure c) correspond to decreased bias with respect to ISAS (i.e. L3Q 1111 SMOS SSS closer to ISAS SSS than L3P SMOS SSS): red color means that the correction improves 1112 most of the time; blue color means that the correction degrades most of the time. Blank colors in 1113 figures c) and d) mean no change above the 0

S. Smos and . Sss, b, e, h) standard 1116 deviation of the differences, (c, f, i) number of pixels used in the comparisons, day L3P SMOS SSS, pp.10-1117, 1118.

, Same indicators but when considering only the pixels available in the four products are 1119 presented in Appendix A2, p.1120

, Scatter plots of SMOS corrected fields versus SMAP SSS on the 4 regions and 1121 fresh events periods illustrated on Figure 1: first line: Bay of Bengal, Figure, vol.6, issue.2

. Mexico, Eastern Tropical Atlantic Freshwater Pools; 4th line : Amazon plume. First 1123 column: SMOS K2016 SSS; second column: SMOS 18-day CEC SSS; last column: SMOS 9- 1124 day CEC SSS, p.1125

, Time series of statistical parameters computed over the Bay of Bengal case study 1126 area: a) mean SSS; b) SSS standard deviation; c) square of the 1127, Figure, vol.7, 2015.

C. Pearson-correlation, between SMOS and SMAP SSS; d) Standard deviation of 1128 the SMOS minus SMAP SSS differences (plain line) using L1 norm (dotted line). 'Weekly' 1129 SMOS CEC(blue), 'bi-weekly' SMOS CEC (green), 'bi-weekly' SMOS K2016 (red), p.1130

, Figure 8: Time series of statistical parameters computed over the Gulf of Mexico case study area, p.1132

, a) mean SSS; b) SSS standard deviation; c) square of the Pearson 1133 correlation coefficient (r2) between SMOS and SMAP SSS; d) Standard deviation of the SMOS 1134 minus SMAP SSS differences (plain line) using L1 norm (dotted line). 'Weekly' SMOS CEC(blue), 1135 'bi-weekly' SMOS CEC (green), bi-weekly' SMOS K2016 (red), 'weekly' SMAP (black), 2015.

, Time series of statistical parameters computed over the Eastern Tropical Atlantic Freshwater 1137 Pools case study area: a) mean SSS; b) SSS standard deviation, Figure, vol.9, p.1138, 2015.

, Pearson correlation coefficient (r2) between SMOS and SMAP SSS; d) Standard 1139 deviation of the SMOS minus SMAP SSS differences (plain line) using L1 norm

. Weekly-'smos and . Cec, bi-weekly' SMOS CEC (green), 'bi-weekly' SMOS K2016 (red), 1141 'weekly' SMAP (black)

, Time series of statistical parameters over the Amazon plume case study area, Figure, vol.10, 1143.

, a) mean SSS; b) SSS standard deviation; c) square of the Pearson correlation 1144 coefficient (r2) between SMOS and SMAP SSS; d) Standard deviation of the SMOS minus SMAP 1145 SSS differences (plain line) using L1 norm (dotted line). 'Weekly' SMOS CEC(blue), 'bi-weekly' 1146 SMOS CEC (green), bi-weekly' SMOS K2016 (red), 'weekly' SMAP (black), 2016.

, Density spectra Bottom: Coherence between ship SSS and SMOS or ISAS SSS. The 1148 spatial frequency (1/wavelength (km)) is indicated below the bottom plot, whereas the corresponding 1149 wavelengths (km) are indicated above the top plot. Vertical dashed lines correspond to spatial 1150 frequencies regularly spaced in logarithmic coordinates. Northern subtropical Atlantic (see box on the 1151 color map) in 2013. Ship SSS measured on regular merchant ships transects (14 regular transects, ISAS SSS (green), pp.10-13, 1152.

, Statistics of ship comparisons) binned as a function of 1155 the distance from the nearest coast: top) mean difference; middle) standard deviation of the 1156 differences; the black line indicates the standard deviation of ship SSS in each class, Figure, vol.12, p.1157, 2010.

, Left: considering only the SMOS pixels common 1158 to all versions; right: considering all pixels available in each version. Ship and SMOS SSS 1159 are integrated over 100 km. Orange: monthly SMOS L3P ; pink : monthly SMOS L3Q, number of pixels used in the comparisons, pp.18-1161, 1160.

, Examples of comparisons between ship SSS (black stars line) and SMOS SSS: orange: non 1162 corrected (L3P), purple: monthly L3Q corrected, light blue :18-day CEC corrected, Figure, vol.13

, Left) from 2014-08-21 to 2014-09-03, Matisse ship. Right) from, 1164.

C. Ship, All SSS products have been smoothed over +/-50 km

, Standard deviation of 'weekly' satellite SSS minus ISAS SSS between 47°N and 1166 47°S, over the year 2016. a) SMOS CEC, b) SMAP CAP, Figure, vol.14, p.1167

, 2012 (top right), 2013 (bottom 1168 left), 2014 (bottom right) in the Atlantic Ocean (1200 km from continents)-SMOS ascending 1169 orbits (blue), descending orbits (red, ISAS(green), 2011.

, SSS latitudinal profiles, Figure, vol.15, pp.2012-2013, 2011.

, 1196 (bottom right) in the Atlantic Ocean (1200 km from continents)-SMOS ascending orbits (blue), descending 1197 orbits (red), ISAS(green)

, SSS latitudinal profiles, Figure, vol.16, pp.2012-2013, 2011.

, 1200 (bottom right) in the Pacific Ocean (1200 km from continents)-SMOS ascending orbits (blue), descending 1201 orbits (red), ISAS(green)

, reference xswath are 1204 chosen as the ones having relatively weak and stable (from one year to another) SMOS minus 1205 ISAS SSS differences (DIFF) over the 45°S-45°N latitudinal range. We did not define a 1206 quantitative criterion for this selection because the patterns of DIFF strongly vary from one 1207 month to another, from ascending to descending orbits and as a function of latitude (not 1208 shown) During most months, reference xswath are located on ascending orbits only. We 1209 illustrate the location of the reference xswath with respect to the median of SMOS minus ISAS 1210 SSS absolute differences for the months of The 1211 locations of all the selected reference xswath are reported in Table 4, Over the 2011-2016 period, p.1212

, Median of SMOS minus ISAS SSS absolute differences as a function of dwell line location 1213 and year, for the month of January (left), May (middle) and September (right), for ascending (top) and 1214 descending (bottom) orbits. The black lines indicate the range of selected xswath, Figure, vol.17

, Table 4: Reference xswath locations 1217 Ascending orbits Descending orbits

A. , , 200250.

, SMOS-SMAP SSS comparison considering only pixels common 1220 to all SSS fields, Appendix, vol.2, p.1221

, Weekly' comparison of SMOS and SMAP SSS: (a, c, e) square of the Pearson 1222 correlation coefficient (r 2 ) , (b, d, f) standard deviation of the difference, L3Q SMOS SSS, (e, f) CEC SMOS SSS. Only pixels common to the four 1224 products are considered in the comparisons, pp.3-1223