CDR Program NOAA MSU Mean Layer Temperature C-ATBD <TBD By CDR Program> Rev. 1 03/01/2014 Climate Data Record (CDR) Program Climate Algorithm Theoretical Basis Document (C-ATBD) NOAA MSU Mean Layer Temperature CDR Program Document Number: TBD by CDR Program Document Manager Originator Document Number: N/A Revision 1 / March 1, 2014 DSR Number: DSR-XXX by CDR Program Document Manager 1 CDR Program NOAA MSU Mean Layer Temperature C-ATBD <TBD By CDR Program> Rev. 1 03/01/2014 REVISION HISTORY Rev. Author DSR No. Description Date 1 Cheng-Zhi Zou and DSR-XXX Initial Submission to CDR Program 03/01/2014 Jian Li NOAA/NESDIS/STAR 2 CDR Program NOAA MSU Mean Layer Temperature C-ATBD <TBD By CDR Program> Rev. 1 03/01/2014 TABLE of CONTENTS 1. INTRODUCTION .............................................................................................................................. 7 1.1 Purpose ..................................................................................................................................................... 7 1.2 Definitions................................................................................................................................................. 7 1.3 Document Maintenance ............................................................................................................................ 8 2. OBSERVING SYSTEMS OVERVIEW .......................................................................................... 10 2.1 Products Generated ................................................................................................................................ 10 2.2 Instrument Characteristics ...................................................................................................................... 10 3. ALGORITHM DESCRIPTION ...................................................................................................... 13 3.1 Algorithm Overview ................................................................................................................................ 13 3.2 Processing Outline................................................................................................................................... 14 3.2.1 Overall Processing Outline ..................................................................................................................... 14 3.2.2 System configuration ............................................................................................................................. 15 3.2.3 Preparing Ancillary data ......................................................................................................................... 16 3.2.4 Converting Level-1C orbit data to Level-3 gridded data ........................................................................ 17 3.2.5 Removing inter-satellite biases .............................................................................................................. 18 3.3 Algorithm Input ....................................................................................................................................... 19 3.3.1 Primary Sensor Data .............................................................................................................................. 19 3.3.2 Ancillary Data ......................................................................................................................................... 19 3.3.3 Derived Data .......................................................................................................................................... 19 3.3.4 Forward Models ..................................................................................................................................... 20 3.4 Theoretical Description ........................................................................................................................... 20 3.4.1 Physical and Mathematical Description ................................................................................................. 20 3.4.2 Data Merging Strategy ........................................................................................................................... 22 3.4.3 Numerical Strategy ................................................................................................................................ 22 3.4.4 Calculations ............................................................................................................................................ 23 3.4.5 Look-Up Table Description ..................................................................................................................... 23 3.4.6 Parameterization ................................................................................................................................... 24 3.4.7 Algorithm Output ................................................................................................................................... 24 4. TEST DATASETS AND OUTPUTS ............................................................................................. 25 4.1 Test Input Datasets ................................................................................................................................. 25 4.2 Test Output Analysis ............................................................................................................................... 25 4.2.1 Reproducibility and Accuracy ................................................................................................................ 25 4.2.2 Error Budget ........................................................................................................................................... 27 5. PRACTICAL CONSIDERATIONS ................................................................................................ 29 5.1 Numerical Computation Considerations .................................................................................................. 29 5.2 Programming and Procedural Considerations ......................................................................................... 29 5.3 Quality Assessment and Diagnostics ....................................................................................................... 29 5.4 Exception Handling ................................................................................................................................. 30 3 CDR Program NOAA MSU Mean Layer Temperature C-ATBD <TBD By CDR Program> Rev. 1 03/01/2014 5.5 Algorithm Validation ............................................................................................................................... 30 5.6 Processing Environment and Resources .................................................................................................. 30 6. ASSUMPTIONS AND LIMITATIONS ........................................................................................ 32 6.1 Algorithm Performance ........................................................................................................................... 32 6.2 Sensor Performance ................................................................................................................................ 32 7. FUTURE ENHANCEMENTS......................................................................................................... 33 8. REFERENCES .................................................................................................................................. 34 APPENDIX A. ACRONYMS AND ABBREVIATIONS ................................................................... 35 4 CDR Program NOAA MSU Mean Layer Temperature C-ATBD <TBD By CDR Program> Rev. 1 03/01/2014 LIST of FIGURES Figure 2-1 Weighting functions for the three MSU atmospheric channels that measure temperatures of the middle-troposphere (TMT), upper-troposphere (TUT), and lower-stratosphere (TLS). The weighting functions correspond to nadir observing conditions for the US standard atmospheric temperature profile .................................................................................................................................................................... 11 Figure 3-1 High level flowchart of the MSU TCDR algorithm illustrating the main processing section. .... 15 Figure 3-2 Input parameter processing flowcharts for (a) generation of level-3 data of individual satellites and (b) merged layer temperature TCDR for different channels ................................................ 16 Figure 3-3 Flowchart for processing IMICA calibrated Level-1c brightness temperature to generate Level- 3 gridded monthly temperature records for individual satellites .............................................................. 17 Figure 3-4 Flowchart for processing level-3 gridded monthly temperature records of all satellites to generate merged deep-layer atmospheric temperature products ............................................................ 18 Figure 4-1 Global ocean-mean inter-satellite brightness temperature difference time series for MSU channel 2 onboard TIROS-N through NOAA-14 derived from (a) the IMICA inter-calibrated radiances, and (b) after applying all bias correction algorithms to the IMICA calibrated radiances. ................................. 26 LIST of TABLES Table 2-1 Products generated in this CDR, which are 28 year-long, global monthly data with 2.5o latitudes by 2.5o longitudes grid resolution ...............................................................................................