Characteristics of GOES13 Sounder IR Detectors Dejiang Han

Characteristics of GOES-13 Sounder IR Detectors Dejiang Han December 22, 2006

Comparisons of Spectral Response Functions for GOES-12 and GOES-13 Sounders (Channels 1 – 9) GOES-12 GOES-13

Comparisons of Spectral Response Functions for GOES-12 and GOES-13 Sounders (Channels 10 – 18) GOES-12 GOES-13

Striping Due to SRF Differences (Channels 1 – 9) GOES-12 GOES-13 ITT provides temperature-to-radiance conversion coefficients, which are determined with the detector spectral response functions. The coefficients are used in the GOES SPS data processing. Plots presented on this page and next show the GVAR count differences within a channel. The difference for each detector is defined as Value (single detector) – Mean Value (all detectors). In the course of Temperature→Radiance →GVAR counts, no detector saturation is taken into account. Symbols used in the plots on this page and those following: + Detector 1 * Detector 2 ◊ Detector 3 ∆ Detector 4 q For channel 7 of both GOES-12 and GOES-13, detector 4 differs from the other three.

Striping Due to SRF Difference (Channels 10 – 18) GOES-12 GOES-13 q For both GOES-12 and GOES-13, channels 11 and 12 have one detector behaving somehow differently from the other three.

GVAR Counts Profiles of GOES-13 Sounder CH 1 – 9 During the ITT’s pre-launch spacecraft T/V tests, the Sounder was directed to view a target, whose temperature was controlled at 295 K. The T/V tests were recorded on a tape, which was played back and processed by the GOES SPS. The above profiles are organized channel by channel. Line types used for each channel are solid: Detector 1 Dotted: detector 2 dashed: Detector 3 dash dotted: Detector 4 (cont’d)

GVAR Counts Profiles of GOES-13 Sounder CH 10 – 18 q Channels 1 - 3, and 12 are saturated. q Channels 7 – 9, 11, and 13 – 15 appear to have one detector whose GVAR count profile is different from the other three. q For GOES-13 Channel 7, in particular, detector 4 seems to stand alone. This is consistent with the spectral response function profiles for the channel. In the GOES-13 NOAA Science Tests, however, the reported detector is detector 3.

Temperature Differences of GOES-13 Sounder CH 1 – 18 Temperature differences observed for each channel of GOES-13 Sounder during the ITT’s pre-launch spacecraft T/V tests.

GOES-13 Sounder Mean and Standard Deviation of Retrieved Temperatures over a Controlled Target Mean 282. 128 281. 980 291. 590 294. 324 294. 345 294. 384 294. 550 294. 336 294. 739 294. 933 294. 970 291. 344 295. 131 295. 090 295. 117 295. 184 295. 189 295. 233 282. 118 281. 974 291. 592 294. 303 294. 298 294. 391 294. 499 294. 311 294. 495 295. 024 295. 080 291. 295. 034 295. 000 294. 991 295. 154 295. 145 295. 212 282. 136 281. 980 291. 590 294. 309 294. 312 294. 369 294. 444 294. 435 294. 551 294. 972 294. 950 291. 339 295. 087 295. 073 295. 101 295. 181 295. 115 295. 271 282. 088 281. 961 291. 584 294. 313 294. 278 294. 336 294. 820 294. 532 294. 540 294. 900 294. 954 291. 317 295. 102 295. 061 295. 084 295. 166 295. 146 295. 223 STD 1. 04609 e-11 3. 29746 e-12 1. 07452 e-11 0. 0922671 0. 102328 0. 0536734 0. 0342686 0. 0452732 0. 0528262 0. 0589241 0. 0409950 3. 41116 e-12 0. 0468195 0. 0430578 0. 0420997 0. 0485417 0. 0487201 0. 0442136 9. 09644 e-12 1. 37015 e-11 1. 47249 e-11 0. 0961847 0. 0922615 0. 0511453 0. 0419468 0. 0409233 0. 0480543 0. 0420942 0. 0342842 5. 40101 e-12 0. 0542628 0. 0574043 0. 0487656 0. 0518586 0. 0591520 0. 0476579 (Vertical: Channels; Horizontal: Detectors) 2. 72893 e-12 1. 17117 e-11 5. 79898 e-12 5. 11675 e-12 2. 22863 e-11 1. 88183 e-11 0. 0993450 0. 106696 0. 102111 0. 0908641 0. 0561833 0. 0395547 0. 0433724 0. 0390956 0. 0338494 0. 0615479 0. 0398897 0. 0583666 0. 0457885 0. 0622064 0. 0342714 0. 0465201 1. 47817 e-12 5. 34416 e-12 0. 0616064 0. 0502991 0. 0412791 0. 0520371 0. 0348367 0. 0526656 0. 0263090 0. 0454805 0. 0535933 0. 0597365 0. 0375237 0. 0406419