MsWG (Apr 22, 2015) Recent L1B LUT delivery since April 8, 2015 Aqua C6 forward update: 6.1.33.7 (4/20/2015) TEB default b1 Aqua C5 forward update: 5.0.41.39 (4/21/2015) TEB default b1 Terra C5 forward update: 5.0.46.89 (4/16/2015) RSB m1, sigma_m1 and RVS, TEB & QA Terra C6 forward update: 6.1.18.7 (4/17/2015) RSB m1, RVS and uncertainty & QA Terra C6 OBPG update: 6.1.18.7_OC2 (4/22/2015) RSB m1, RVS and uncertainty MODIS instrument status Terra and Aqua MODIS are in nominal operations Aqua IAM #46 successfully completed: 2015/105 15:16:28 – 16:02:48 Aqua IAM #47 scheduled for 2015/112 (4/22/15) ~15:33:28 Terra DMU #91 scheduled for 2015/112 (4/22/15) ~14:01:50 MCST recent Activities Sector Rotation Code Fix delivered C5/C6 Terra B36 D7 QA (slides 2-6) Aqua CFPA Discussion (slides 7-21) Around the table Page 1

Terra B36 D7 QA Terra Band 36 Det. 7P.O. had previous similar occurrences reported anomalies (for list refer next slide) Anomaly Type: Electronic Formatter Error Starting from 2015/092 17:40(GMT) BB DN, SV DN values flip between 4095 and 0 Behavior continues as of today (2015/112) Exact cause of behavior is unknown No Anomaly Periods Time in Day/Hrs 1 2008(179.2040-181.0700) ~1D and 10H 2 2008(358.1805-359.1750) ~ 1D 3 2010(006.1045-009.0355) ~2D and17H 4 2010(242.1025-242.1205) ~2H 5 2011(039.0440-039.1140) ~7H 6 2011(093.0205-093.0810) ~6H 7 2011(112.2225-113.1205) ~14 H 8 2011(211.1620-211.2030) ~4H 9 2012(014.0510-014.1050) ~5H 10 2012(137.0025 – 181.0645) ~44D 11 2014(109.1405 – 222.0000) 113D+ 12 2015(092.1740 – present) 20D+ Page 2

Daily b1 and NEdT Trending b1 / NEdT trending for 2015-092 17:40:00 (GMT) Page 3

Daily DN BB & SV trends (2015/092) <DN_SV> dn_BB Page 4

Daily DN BB & SV trends (2015/104) <DN_SV> dn_BB Page 5

Summary and Recommendation Terra Band 36 Det. 7 has exhibited anomalous behavior beginning 2015092.1740 through the present, over 14 days continuously. The result is a number of invalid scans (striping) in the L1B product. Based on previous instances the QA flag was changed from ‘noisy’ to ‘inoperable’ for this detector in C5/C6 from 2015092.1740 forward. Page 6

Aqua MODIS Cold FPA Performance and Operation MODIS Characterization Support Team (MCST) April 22, 2015 Page 7

Outline Introduction On-orbit Performance Update Observed Impacts Mitigation Strategies Summary Page 8

Introduction Aqua MODIS Cold Focal Plane Temperature Control Known issue with decreasing radiative cooler margin Prior meetings held to brief science disciplines on status, impacts and possible mitigation strategies 1st meeting on May 7, 2010 2nd meeting on April 25, 2012 3rd meeting on March 17, 2013 4th meeting on April, 16, 2014 MCST continues to monitor instrument performance Impacts observed that can affect science products Orbital variation in TEB detector gain (PC bands more sensitive) Increased fitting residuals from BB WUCD during a0/a2 derivation Saturation in bands 33, 35-36 EV data during WUCD Page 9

Current Status CFPA temperature peak during summer months with maximum ~83.7 K in mid-2013. Peak temperature has decreased in 2014 and 2015 CFPA orbital/seasonal oscillation – max/min difference ~0.4 K Radiative cooler margin lost for CFPA setpoint of 83 K during intermittent periods through annual cycle. Majority of impacts on L1B products occur during BB Warmup/Cooldown activities Page 10

BB Temp Trends Terra Aqua 25 mK 5 mK Weekly average (Cal events excluded) Page 11

Warm FPA Temperatures Terra Aqua ~3.5K increase over 15+ years Weekly average (Cal events excluded) Page 12

Cold FPA Temperatures Terra Aqua Weekly average (Cal events excluded) Page 13

Aqua CFPA Oscillations Long-term trend Max/Min of 4 orbits Page 14

Aqua CFPA Oscillations Long-term trend Max/Min of 4 orbits Page 15

Aqua CFPA Oscillations Short Term (DOY 100) trend 2003 2009 Max ~83.0 K Max ~83.1 K SMIR LWIR 2010 2011 Max ~83.15 K Max ~83.2 K Granule average x-axis = granule # Page 16

Aqua CFPA Oscillations Short Term (DOY 100) trend SMIR LWIR 2012 2013 Max ~83.3 K Max ~83.4 K 2014 2015 Max ~83.3 K Max ~83.25 K Granule average Page 17

Heater Voltage Trend CFPA temperature not controlled for intermittent periods 1 orbit average Page 18

Observed Impacts Improved temperature performance since last meeting Gain variation with CFPA temperature captured by scan-by-scan calibration PC bands show largest effect Linear relationship between gain and CFPA Temp BB Warmup-Cooldown Activities Larger residuals for a2 derivation (a0 = 0 for PC bands) Temperature correction for a0/a2 analysis implemented in C6 Bands 33, 35 & 36 TBB Saturation Increased instances of EV saturation Cumulative saturation during WUCD: 2004/203 - B33: 0 min., B35: 0 min, B36: 0 min 2009/123 – B33: 7 min, B35: 13 min, B36: 0 min 2013/174 - B33: 200 min, B35: 95 min, B36: 37 min 2015/032 - B33: 161 min, B35: 105 min, B36: 37 min FPA temperature dependent default b1 algorithm implemented for C5/C6 Page 19

Mitigation Strategies Options under consideration to address temperature fluctuations No change – continue operations in current configuration Change CFPA set point to 85K Perform Outgas (requires NASA HQ approval) Reduce frequency of WUCD activities Upload modified DCR table for bands 33, 35 & 36 (reduce saturation during WUCD) – may impact dynamic range for bands Page 20

Summary Aqua MODIS continues to operate nominally A decrease in radiative cooler margin has been observed since ~2007. CFPA temperature not able to be stably controlled at set point of 83 K Orbital and seasonal variations observed Maximum SMIR temperature reached in mid-2013, temperature performance has improved since then Scan-by-scan calibration captures much of the impact of the CFPA variation Collection 6 includes an improved default b1 algorithm and temperature correction to the a0/a2 analysis. EV saturation for bands 33, 35 & 36 during WUCD activities continues. MCST continues monitoring of CFPA performance. No reports received of adverse impacts on science products. MCST Recommendation: Option 1 – No change in operation status Page 21

Backup Slides Page 22

Option 2 – Change CFPA Set Point to 85K S/C needs to be in “nominal mode” for this activity Ensure that CFPA heater B is in the ON state Send the following commands: SET_RC_CFPA_TEMP TO 1/2/3 MOD_SET_PM_RC_CFPA_TEMP(‘T2’)‏ Monitor telemetry to ensure that the CFPA temperature adjusts accordingly (real time until it stabilizes) Advantages: Gain stably controlled EV saturation during WUCD decreased Increase in dynamic range for some TEB Concerns: Majority of pre-launch LUT tables based on 83 K set point DCR table for 85 K Decreased radiometric resolution for some TEB Increased detector noise Page 23

Option 3 - Outgas An outgas without an anomaly requires transitioning MODIS from science mode to standby mode and then to outgas mode Doors are closed, except SV door is moved to outgas position This operation/action may require approval from HQ An outgas requires a set of commands and takes 2-3 days to complete (heaters are turned on in specific sequence) CFPA will be back to ambient temperature during outgas operation Potential impact on SWIR (band 6 in particular) detector operability IOT prepared for and has approval to perform an outgas in the event of spacecraft anomaly resulting in a safe mode transition. Page 24

Option 5 – Modify DCR Table CFPA setpoint remains at 83 K DCR table for bands 33, 35 & 36 modified and uploaded Expected to reduce EV saturation during WUCD Can be performed by IOT as a regular table upload to MODIS. Page 25