## 4 NOAA-20 Algorithm Upgrades and Science Data Products  
Launched on 18 November 2017 with a 50-min separation from the S-NPP orbit, NOAA-20 carries aboard it the same instrument complements currently operating on S-NPP. This provides both continuity of the existing high-quality data products currently produced through S-NPP, and additional products as a direct result of the instrument upgrades and science improvements. Feedback from S-NPP product development, Cal/Val, maturity reviews, and user communities has allowed the JSTAR teams to realize a large number of science improvements and upgrades for both existing S-NPP algorithms and many new products. Some of these science improvements and upgrades have already been implemented as part of S-NPP product upgrades. In addition to the science improvements, the JSTAR teams developed necessary algorithm upgrades and mitigations prior to the NOAA-20 launch based on pre-launch characterizations of the instruments. During the pre-launch phase, the JSTAR teams facilitated performance analysis of pre-launch test data, such as instrument configuration parameters (or calibration LUTs), improvements and refinements to mitigate instrument waivers. The JSTAR teams also verified NOAA-20 science algorithm developments related to instrument upgrades using proxy data sets derived from S-NPP and NOAA-20 pre-launch test data sets. All NOAA-20 SDR pre-launch product algorithms were implemented in the IDPS, and most of the EDR algorithms have been migrated to enterprise algorithms for operationalization in NDE. Following the launch of the NOAA-20 satellite, various testing activities have allowed the JSTAR teams to successfully monitor, evaluate, and quantify changes from the pre-launch versions of the NOAA-20 science datasets (e.g., radiometric, spectral, and geometric changes). The JSTAR teams accomplished most of the first 90 day planned science activities to achieve Beta and Provisional Maturity for NOAA-20 KPP products using on-orbit performance and calibration data and after \begin{table}
\begin{tabular}{c c c} \hline \hline
**Product** & **Requirement** & **Performance** \\ \hline Cloud Liquid Water & & \\ Uncertainty (over ocean) & 0.05 mm & 0.03–0.09 mm \\ Accuracy & 0.01 mm & 0.01 mm \\ Total Precipitable Water & & \\ Uncertainty & 2 mm or 10\% & 1.0–1.8 mm \\ Accuracy & 1 mm & 0.1–0.7 mm \\ Precipitation (type/rate) & & \\ Precision & 0.05 mm/h & 0.01 mm/h \\ Uncertainty, over ocean & 2 mm/h & 1.2–1.4 mm/h \\ Uncertainty, over land & 5 mm/h & 3.1–3.6 mm/h \\ Sea surface temperature & & \\ Uncertainty & 1.0 K & 0.5–0.7 K \\ Accuracy & 0.5 K & 0.1–0.2 K \\ Sea surface wind speed & & \\ Uncertainty & 2.0 m/s or 10\% & 0.9–1.5 m/s \\ Accuracy & 0.5 m/s & 0.1–0.3 m/s \\ Sea ice & & \\ Ice concentration, uncertainty & 10\% & 3.9\% NH; 4.4\% SH \\ Ice type, \% correct typing & 70\% & 80–90\%, Arctic winter \\ Snow & & \\ Snow depth, uncertainty & 20 cm & 15–22 cm \\ Snow cover, \% correct typing & 80\% & 72–97\% \\ Snow water equivalent & & \\ Uncertainty & 50–70\% & 20–22\% \\ Soil moisture & & \\ Uncertainty & 6\% & 5\% \\ \hline \hline \end{tabular}
\end{table} 
Table 15: GCM-AMSR2 products performance. accommodating post-launch fixes and updates to calibrate LUTs. All NOAA-20 KPPs (SDRs and imagery products) were declared to have Beta maturity as of 25 January 2018, Provisional maturity as of 16 February 2018, and Validated maturity as of October 2018. NOAA NESDIS promoted all of these SDR products into operation after attaining provisional maturity status. The science teams adapted S-NPP EDR validated maturity algorithms for NOAA-20 and updated the algorithms with the other specific NOAA-20 sensor characteristics to define the NOAA-20 EDR product algorithms. The JSTAR teams initiated the execution of Cal/Val plans and schedules for all of the EDR products. Figure 16 shows the expedited schedule of the Cal/Val and product validated maturity for NOAA-20 SDR/EDR products.