MODIS DB Cloud Top Property and Cloud Phase Output Product Description ------------------------------------------- The Direct Broadcast output file differs from the operational MOD06 output file in that: 1) It is a 4 byte float binary flat file instead of HDF. All parameters (bands) are of type 4 byte float. 2) There are two .img and two .hdr files representing the 48 operational MOD06 HDF SDS's listed below, and the MOD06 HDF SDS Quality_Assurance_5km. 3) There are no geolocation or solar and viewing geometry parameters included as part of the Direct Broadcast product. 4) The output product consists of 48 band interleaved parameters instead of individual HDF file SDS's. 5) The output product does not include several operational MOD06 SDS's. These are: Effective_Particle_Radius Cloud_Optical_Thickness Effective_Radius_Difference Water_Path Cirrus_Reflectance Cirrus_Reflectance_Flag Cloud_Mask_5km Cloud_Mask_1km Quality_Assurance_1km 6) The Quality_Assurance_5km array indices are ordered differently. The DB mod06qa.img order is (element,line,qa_byte), while the DAAC operational HDF SDS is ordered (qa_byte,element,line). This IMAPPv1.3.1 cloud mask product release corresponds to the MOD06CT operational version 3.1.0 delivered to the Goddard DAAC on 15 March 2002. -------------------------------------------------------------------------- The cloud top propery output file product consists of two separate .img files in flat binary format, and accompanying header files. The mod06.img file is a 48 float band interleaved product at 5x5 1km pixel resolution. Please see a list of these bands below. The parameters correspond to the DAAC Production HDF MOD06 product SDS's. The test output file that you create from the input test data sets contains the nominal MODIS swath size 270 (1354/5 elements) and 408 lines (204 scans/5). Therefore, the product mod06.img file is 270 elements, by 48 bands (parameters), by 408 lines. In FORTRAN, it would be read as cloud_properties(270,48,408). This would be reversed in C - cloud_properties(408,48,270). The mod06qa.img file is a 10 byte per pixel product with information at the bit level. Please see the bit description below. This corresponds to the DAAC Production HDF MOD06 product SDS Quality_Assurance_5km. It contains information on the quality of individual output parameters, as well as some ancillary data information. The test output file that you create from the input test data sets contains the nominal MODIS swath size 270 (1354/5 elements) and 408 lines (204 scans/5). Therefore, product mod06qa.img file is 10 bytes, by 408 lines, by 270 elements. In FORTRAN, it would be read as cloud_properties_qa(270,408,10). This would be reversed in C - cloud_propertiesqa(10,408,270). -------------------------------------------------------------------------- MODIS Direct Broadcast MOD06 mod06.img file description Four byte float data 48 parameters 5x5 1km-pixel resolution Band Interleaved fill value = -327.68 band names = { band 1: Brightness_Temperature_B29, band 2: Brightness_Temperature_B31, band 3: Brightness_Temperature_B32, band 4: Brightness_Temperature_B33, band 5: Brightness_Temperature_B34, band 6: Brightness_Temperature_B35, band 7: Brightness_Temperature_B36, band 8: Surface_Temperature, band 9: Surface_Pressure, band 10: Processing_Flag, band 11: Cloud_Height_Method, band 12: Cloud_Top_Pressure, band 13: Cloud_Top_Pressure_Night, band 14: Cloud_Top_Pressure_Day, band 15: Cloud_Top_Temperature, band 16: Cloud_Top_Temperature_Night, band 17: Cloud_Top_Temperature_Day, band 18: Tropopause_Height, band 19: Cloud_Fraction, band 20: Cloud_Fraction_Night, band 21: Cloud_Fraction_Day, band 22: Cloud_Effective_Emissivity, band 23: Cloud_Effective_Emissivity_Night, band 24: Cloud_Effective_Emissivity_Day, band 25: Cloud_Top_Pressure_Infrared, band 26: Spectral_Cloud_Forcing_B36, band 27: Spectral_Cloud_Forcing_B35, band 28: Spectral_Cloud_Forcing_B34, band 29: Spectral_Cloud_Forcing_B33, band 30: Spectral_Cloud_Forcing_B31, band 31: Cloud_Top_Pressure_From_Ratios_36/35, band 32: Cloud_Top_Pressure_From_Ratios_35/34, band 33: Cloud_Top_Pressure_From_Ratios_35/33, band 34: Cloud_Top_Pressure_From_Ratios_34/33, band 35: Cloud_Top_Pressure_From_Ratios_33/31, band 36: Surface_Type, band 37: Radiance_Variance_B29, band 38: Radiance_Variance_B31, band 39: Radiance_Variance_B32, band 40: Radiance_Variance_B33, band 41: Radiance_Variance_B34, band 42: Radiance_Variance_B35, band 43: Radiance_Variance_B36, band 44: Brightness_Temperature_Difference_B29-B31, band 45: Brightness_Temperature_Difference_B31-B32, band 46: Cloud_Phase_Infrared, band 47: Cloud_Phase_Infrared_Night, band 48: Cloud_Phase_Infrared_Day } band units = { band 1: tmp, band 2: tmp, band 3: tmp, band 4: tmp, band 5: tmp, band 6: tmp, band 7: tmp, band 8: tmp, band 9: msl, band 10: flg, band 11: flg, band 12: hPa, band 13: hPa, band 14: hPa, band 15: tmp, band 16: tmp, band 17: tmp, band 18: hPa, band 19: pct, band 20: pct, band 21: pct, band 22: pct, band 23: pct, band 24: pct, band 25: hPa, band 26: rad, band 27: rad, band 28: rad, band 29: rad, band 30: rad, band 31: hPa, band 32: hPa, band 33: hPa, band 34: hPa, band 35: hPa, band 36: flg, band 37: rad, band 38: rad, band 39: rad, band 40: rad, band 41: rad, band 42: rad, band 43: rad, band 44: tmp, band 45: tmp, band 46: flg, band 47: flg, band 48: flg } MODIS DB Cloud Top Property and Cloud Phase Output Quality Assurance Product Description (mod06qa.img) ------------------------------------------- 10 bytes per retrieval Bit level information 5x5 1km-pixel resolution Byte Sequential fill value = -1 Common Runtime QA (Cloud Mask) Flags bit field Number of Bits Bit value and Description --------- ----------- ----------------------- Cloud Top 1 0 = Not useful Pressure QA 1 = Useful Cloud Top 3 0-3 Confidence levels Pressure 0:Bad-3:Very Good Confidence QA Cloud Top 1 0 = Not useful Temperature 1 = Useful Confidence QA Cloud Top 3 0-3 Confidence levels Temperature 0:Bad-3:Very Good Confidence QA ____ END BYTE 1 _________________________________________________________ bit field Number of Bits Bit value and Description --------- ----------- ----------------------- Cloud Fraction 1 0 = Not useful QA 1 = Useful Cloud Fraction 3 0-3 Confidence levels Confidence QA 0:Bad-3:Very Good Cloud Effective 1 0 = Not useful Emissivity QA 1 = Useful Cloud Effective 3 0-3 Confidence levels Emissivity 0:Bad-3:Very Good Confidence QA ____ END BYTE 2 _________________________________________________________ bit field Number of Bits Bit value and Description --------- ----------- ----------------------- Cloud Phase 1 0 = Not useful Infrared QA 1 = Useful Cloud Phase 3 0-3 Confidence levels Infrared 0:Bad-3:Very Good Confidence QA Retrieval processing QA flags - processing path flags Cirrus Level 2 0 - missing 3 flag 1 - no cirrus found 2 - cirrus found High Cloud 2 0 - missing Level 3 Flag 1 - no high cloud found 2 - high cloud found ____ END BYTE 3 _________________________________________________________ bit field Number of Bits Bit value and Description --------- ----------- ----------------------- Number of Cloudy Pixels Int 8 0-25 cloudy pixels in 5x5 box ____ END BYTE 4 _________________________________________________________ Number of Clear Pixels Int 8 0-25 clear pixels in 5x5 box ____ END BYTE 5 _________________________________________________________ Number of Missing Pixels Int 8 0-25 missing data pixels in 5x5 box ____ END BYTE 6 _________________________________________________________ Remainder of bytes currently not used.