TITLE: "indoex-nfov_aimr_tmi_avhrr" P.I.: Francisco P.J. Valero 9500 Gilman Dr., Dept. 0242 La Jolla, CA 92093-0242 Phone: 858-534-2701 FAX: 858-822-0517 Email: fvalero@ucsd.edu 1.0 DATA SET OVERVIEW This data set is a compilation of 4 independent data sets acquired during the INDOEX Intensive Field Phase. Each data set has been averaged to a common time database corresponding to the duration of the NCAR C-130 aircraft. In the case of satellite measurements (TMI data from the TRMM satellite and AVHRR data aboard the NOAA-14 satellite), the data has also been co-located to the latitude/longitude location of the NCAR C-130 at the specified time. A summary of the data available from the INDOEX research flights and dates is tabulated below: RF # YYYYMMDD RF # YYYYMMDD ---- -------- ---- -------- RF01 19990216 RF10 19990309 RF02 19990218 RF11 19990311 RF03 19990220 RF12 19990313 RF04 19990224 RF13 19990316 RF05 19990225 RF14 19990318 RF06 19990227 RF15 19990319 RF07 19990228 RF16 19990321 RF08 19990304 RF17 19990324 RF18 19990325 More information about the INDOEX campaign may be found at the following WWW site: http://www-indoex.ucsd.edu/ A brief description of the data sets contained in this archive is listed below: NCAR C-130 The C-130 aircraft was operated by the National Center for Atmospheric Research, Research Aviation Facility. NFOV The Narrow Field of View (NFOV) radiometer was flown on board the NCAR C-130 as part of the Radiation Measurement System (RAMS). The NFOV was operated by the Atmospheric Research Laboratory at the Scripps Institution of Oceanography. AIMR (http://www.joss.ucar.edu/cgi-bin/codiac/dss?22.001) The Airborne Imaging Microwave Radiometer (AIMR) was flown on board the NCAR C-130. AIMR was operated by the ATD division of the National Center for Atmospheric Research. TMI (http://tsdis.gsfc.nasa.gov/tsdis/tsdis.html) The TRMM (Tropical Rainfall Measuring Mission) satellite is the first mission dedicated to measuring tropical and subtropical rainfall through microwave and visible infrared sensors, and includes the first spaceborne rain radar. The TRMM Microwave Imager (TMI) is one of three rain instruments carried aboard the TRMM satellite. AVHRR (http://www.joss.ucar.edu/cgi-bin/codiac/dss?22.108) This dataset contains daily NOAA-14 AVHRR 4-km Global Area Coverage (GAC) measurements that were collected for January-March 1996-2000. Analyses were performed for ascending daytime passes in the INDOEX region: 30S to 30N and 50E to 110E. The data were analyzed on a 60 by 60 1 degree latitude-longitude grid to produce daily, weekly, and monthly composites of data for the INDOEX region. 2.0 INSTRUMENT DESCRIPTION NCAR C-130 (http://www.atd.ucar.edu/raf/Projects/INDOEX/docsum.html) Documentation summary for all of the airborne measurements aboard the NSF/NCAR Research Aviation Facility (RAF) EC-130Q Hercules aircraft during INDOEX may be found at the above WWW site. Aircraft data products archived in this data set are altitude, latitude, longitude, pitch, roll, and heading. NFOV The NFOV consists of two separate cryogenic radiometers sensitive to upwelling radiances in the 4-50 micron (Channel #1) and 10-11 micron (Channel #2) infrared bands. Absolute calibration is completed in the laboratory via a temperature controlled thermal bath and black-body reference. A narrow FOV to hemispherical FOV conversion is applied to the final data set thus giving an effective irradiance (W m-2) measurement. Each NFOV channel has an absolute accuracy of 2-3%. AIMR (http://www.joss.ucar.edu/data/indoex/docs/AIMR_walther.txt) AIMR has four radiometric channels, two orthogonally polarized channels at 37 GHz and two at 90 GHz. The channels are polarized in a manner such that the amount of vertically polarized radiation and the amount of horizontally polarized radiation can be uniquely calculated at most look angles of the instrument. These channels are detected and amplified by receivers whose outputs are digitized and written on tape by a set of computer systems. The base products from the radiometer are the brightness temperatures, of each of the four channels, at each sample location. AIMR data products that are archived in this data set are the 37 and 90 GHz brightness temperatures in the nadir viewing direction as well as both the horizontal and vertical polarization components of the 37 and 90 GHz brightness temperatures at viewing angles of 30 degrees relative to nadir in the scan plane of the instrument. TMI (http://tsdis.gsfc.nasa.gov/tsdis/tsdis.html) TRMM Microwave Imager, a nine-channel, five-frequency (dual polarization for 10.65, 19.35, 37, and 85.5 GHz, and vertical polarization for 21 GHz) microwave radiometer, one of three rain instruments carried on board the TRMM satellite. The TMI data products that are archived in this data set are: Sea Surface Temperature, 10 meter surface wind speed (using 11 GHz nd 37 GHz channels), Columnar Atmospheric Water Vapor, Liquid Cloud Water, and Derived Radiometer Rain Rate AVHRR (http://www.joss.ucar.edu/data/indoex/docs/aero_opt_dpth_coakley.txt) This dataset contains daily NOAA-14 AVHRR 4-km Global Area Coverage (GAC) measurements that were collected for January-March 1996-2000. Analyses were performed for ascending daytime passes in the INDOEX region: 30S to 30N and 50E to 110E. The data were analyzed on a 60 by 60 1 degree latitude-longitude grid to produce daily, weekly, and monthly composites of data for the INDOEX region. Optical depths are archived at 0.55, 0.65, 0.80, and 0.90 micron wavelengths. 3.0 DATA COLLECTION AND PROCESSING The NCAR/RAF aircraft measurements, AIMR, TMI, and AVHRR data products were all obtained via the INDOEX CODIAC Data Management System maintained by the University Corporation for Atmospheric Research (UCAR) Joint Office for Science Support (JOSS), Boulder, Colorado, USA. The NFOV data was acquired by personnel from the Atmospheric Research Laboratory, Scripps Institution of Oceanography aboard the Radiation Measurement System aboard the NCAR C-130. The NFOV data is a previously unreleased data set. All of the data sets have been co-located in time and location to the flight track of the NCAR C-130 aircraft. Some specific conditions of the co-locations for each of the data sets is described below. For all variables, an associated standard deviation accompanies each parameter that represents the variability of the data associated with the averaging. In the case of missing or bad data, each of the variables are flagged with a value of "-999.999". NCAR C-130 Aircraft Parameters All variables are averaged during 10 second intervals centered at the indicated time. NFOV All variables are averaged during 10 second intervals centered at the indicated time. Conditions when the aircraft is not flying "wings-level" are flagged. AIMR All variables are averaged during 10 second intervals centered at the indicated time. Conditions when the aircraft is not flying "wings-level" are flagged. The 37 and 90 GHz brightness temperatures are limited to nadir viewing conditions (scan pixels 90-110). The horizontal and vertical polarizations of the 37 and 90 GHz brightness temperatures and limited to viewing angles of about 30 degrees off of nadir in the scan plane (scan pixels 40-60 and 140-160). TMI The TMI data set used in this archive comes gridded versus latitude and longitude for a given 3-day mean, ending on the date of the INDOEX research flight. For each latitude/longitude pair associated with the C-130 at a given time during the flight, the grid-box of the 2-D TMI data set is determined and a 2-D interpolation of data from the four corners is applied. In cases where any one of the four corners of the TMI grid-box is missing or flagged, the resulting interpolated data product is also flagged. After the variable is co-located to the C-130 flight track, it is then averaged during 10 second intervals centered at the indicated time. AVHRR The AVHRR data set used in this archive comes gridded versus latitude and longitude on the date of the INDOEX research flight in which the satellite made an overpass of the region. For each latitude/longitude pair associated with the C-130 at a given time during the flight, the grid-box of the 2-D AVHRR data set is determined and a 2-D interpolation of data from the four corners is applied. In cases where any one of the four corners of the AVHRR grid-box is missing or flagged, the resulting interpolated data product is also flagged. After the variable is co-located to the C-130 flight track, it is then averaged during 10 second intervals centered at the indicated time. 4.0 DATA FORMAT All data files are named with the following convention: indoex-nfov_aimr_tmi_avhrr.YYYYMMDD.RFXX.cdf where "YYYYMMDD" is the year, month, day of the research flight and "XX" is the flight number during the INDOEX campaign. The data set is in NetCDF format. A sample of the NetCDF header is given below. For all variables, an associated standard deviation accompanies each parameter that represents the variability of the data associated with the averaging. In the case of missing or bad data, each of the variables are flagged with a value of "-999.999". Sample Net CDF Header: dimensions: time = 2832 ; variables: float TIME(time) ; TIME:name = "time (GMT seconds)" ; TIME:note = "All points represent averages over 10.0 second intervals centered at the indicated time" ; float ALTITUDE(time) ; ALTITUDE:name = "Altitude" ; ALTITUDE:units = "km" ; ALTITUDE:flag = -999.999f ; float ALTITUDE_STD(time) ; ALTITUDE_STD:name = "Altitude Standard Deviation" ; ALTITUDE_STD:units = "km" ; ALTITUDE_STD:flag = -999.999f ; float LATITUDE(time) ; LATITUDE:name = "Latitude" ; LATITUDE:units = "degrees" ; LATITUDE:flag = -999.999f ; float LATITUDE_STD(time) ; LATITUDE_STD:name = "Latitude Standard Deviation" ; LATITUDE_STD:units = "degrees" ; LATITUDE_STD:flag = -999.999f ; float LONGITUDE(time) ; LONGITUDE:name = "Longitude" ; LONGITUDE:units = "degrees" ; LONGITUDE:flag = -999.999f ; float LONGITUDE_STD(time) ; LONGITUDE_STD:name = "Longitude Standard Deviation" ; LONGITUDE_STD:units = "degrees" ; LONGITUDE_STD:flag = -999.999f ; float PITCH(time) ; PITCH:name = "Aircraft Pitch Angle" ; PITCH:units = "degrees" ; PITCH:flag = -999.999f ; float PITCH_STD(time) ; PITCH_STD:name = "Aircraft Pitch Angle Standard Deviation" ; PITCH_STD:units = "degrees" ; PITCH_STD:flag = -999.999f ; float ROLL(time) ; ROLL:name = "Aircraft Roll Angle" ; ROLL:units = "degrees" ; ROLL:flag = -999.999f ; float ROLL_STD(time) ; ROLL_STD:name = "Aircraft Roll Angle Standard Deviation" ; ROLL_STD:units = "degrees" ; ROLL_STD:flag = -999.999f ; float HEAD(time) ; HEAD:name = "Aircraft Heading" ; HEAD:units = "degrees" ; HEAD:flag = -999.999f ; float HEAD_STD(time) ; HEAD_STD:name = "Aircraft Heading Standard Deviation" ; HEAD_STD:units = "degrees" ; HEAD_STD:flag = -999.999f ; float NFOV_CH1(time) ; NFOV_CH1:name = "Narrow FOV Radiometer Ch#1 (4.0-50.0 microns)" ; NFOV_CH1:units = "W/m2" ; NFOV_CH1:flag = -999.999f ; float NFOV_CH1_STD(time) ; NFOV_CH1_STD:name = "NFOV Ch#1 Standard Deviation" ; NFOV_CH1_STD:units = "W/m2" ; NFOV_CH1_STD:flag = -999.999f ; float NFOV_CH2(time) ; NFOV_CH2:name = "Narrow FOV Radiometer Ch#2 (10.0-11.0 microns)" ; NFOV_CH2:units = "W/m2" ; NFOV_CH2:flag = -999.999f ; float NFOV_CH2_STD(time) ; NFOV_CH2_STD:name = "NFOV Ch#2 Standard Deviation" ; NFOV_CH2_STD:units = "W/m2" ; NFOV_CH2_STD:flag = -999.999f ; float AIMR_BT37(time) ; AIMR_BT37:name = "AIMR 37 GHz Brightness Temperature" ; AIMR_BT37:units = "K" ; AIMR_BT37:flag = -999.999f ; AIMR_BT37:note = "Nadir viewing" ; float AIMR_BT37_STD(time) ; AIMR_BT37_STD:name = "AIMR 37 GHz Brightness Temperature Standard Deviation" ; AIMR_BT37_STD:units = "K" ; AIMR_BT37_STD:flag = -999.999f ; float AIMR_BT37H(time) ; AIMR_BT37H:name = "AIMR 37 GHz (Horizontal Polarization) Brightness Temperature" ; AIMR_BT37H:units = "K" ; AIMR_BT37H:flag = -999.999f ; AIMR_BT37H:note = "Viewing at 30 degrees from nadir" ; float AIMR_BT37H_STD(time) ; AIMR_BT37H_STD:name = "AIMR 37 GHz (Horizontal Polarization) Brightness Temperature Standard Deviation" ; AIMR_BT37H_STD:units = "K" ; AIMR_BT37H_STD:flag = -999.999f ; float AIMR_BT37V(time) ; AIMR_BT37V:name = "AIMR 37 GHz (Vertical Polarization) Brightness Temperature" ; AIMR_BT37V:units = "K" ; AIMR_BT37V:flag = -999.999f ; AIMR_BT37V:note = "Viewing at 30 degrees from nadir" ; float AIMR_BT37V_STD(time) ; AIMR_BT37V_STD:name = "AIMR 37 GHz (Vertical Polarization) Brightness Temperature Standard Deviation" ; AIMR_BT37V_STD:units = "K" ; AIMR_BT37V_STD:flag = -999.999f ; float AIMR_BT90(time) ; AIMR_BT90:name = "AIMR 90 GHz Brightness Temperature" ; AIMR_BT90:units = "K" ; AIMR_BT90:flag = -999.999f ; AIMR_BT90:note = "Nadir viewing" ; float AIMR_BT90_STD(time) ; AIMR_BT90_STD:name = "AIMR 90 GHz Brightness Temperature Standard Deviation" ; AIMR_BT90_STD:units = "K" ; AIMR_BT90_STD:flag = -999.999f ; float AIMR_BT90H(time) ; AIMR_BT90H:name = "AIMR 90 GHz (Horizontal Polarization) Brightness Temperature" ; AIMR_BT90H:units = "K" ; AIMR_BT90H:flag = -999.999f ; AIMR_BT90H:note = "Viewing at 30 degrees from nadir" ; float AIMR_BT90H_STD(time) ; AIMR_BT90H_STD:name = "AIMR 90 (Horizontal Polarization) GHz Brightness Temperature Standard Deviation" ; AIMR_BT90H_STD:units = "K" ; AIMR_BT90H_STD:flag = -999.999f ; float AIMR_BT90V(time) ; AIMR_BT90V:name = "AIMR 90 GHz (Vertical Polarization) Brightness Temperature" ; AIMR_BT90V:units = "K" ; AIMR_BT90V:flag = -999.999f ; AIMR_BT90V:note = "Viewing at 30 degrees from nadir" ; float AIMR_BT90V_STD(time) ; AIMR_BT90V_STD:name = "AIMR 90 GHz (Vertical Polarization) Brightness Temperature Standard Deviation" ; AIMR_BT90V_STD:units = "K" ; AIMR_BT90V_STD:flag = -999.999f ; float TMI_SST(time) ; TMI_SST:name = "TMI Sea Surface Temperature" ; TMI_SST:units = "K" ; TMI_SST:flag = -999.999f ; float TMI_SST_STD(time) ; TMI_SST_STD:name = "TMI Sea Surface Temperature Standard Deviation" ; TMI_SST_STD:units = "K" ; TMI_SST_STD:flag = -999.999f ; float TMI_W11(time) ; TMI_W11:name = "TMI 10 meter surface wind speed (using 11 GHz channel)" ; TMI_W11:units = "m/s" ; TMI_W11:flag = -999.999f ; float TMI_W11_STD(time) ; TMI_W11_STD:name = "TMI 10 meter surface wind speed (using 11 GHz channel) Standard Deviation" ; TMI_W11_STD:units = "m/s" ; TMI_W11_STD:flag = -999.999f ; float TMI_W37(time) ; TMI_W37:name = "TMI 10 meter surface wind speed (using 37 GHz channel)" ; TMI_W37:units = "m/s" ; TMI_W37:flag = -999.999f ; float TMI_W37_STD(time) ; TMI_W37_STD:name = "TMI 10 meter surface wind speed (using 37 GHz channel) Standard Deviation" ; TMI_W37_STD:units = "m/s" ; TMI_W37_STD:flag = -999.999f ; float TMI_WATER_VAPOR(time) ; TMI_WATER_VAPOR:name = "TMI Columnar Atmospheric Water Vapor" ; TMI_WATER_VAPOR:units = "mm" ; TMI_WATER_VAPOR:flag = -999.999f ; float TMI_WATER_VAPOR_STD(time) ; TMI_WATER_VAPOR_STD:name = "TMI Columnar Atmospheric Water Vapor Standard Deviation" ; TMI_WATER_VAPOR_STD:units = "mm" ; TMI_WATER_VAPOR_STD:flag = -999.999f ; float TMI_CLOUD_WATER(time) ; TMI_CLOUD_WATER:name = "TMI Liquid Cloud Water" ; TMI_CLOUD_WATER:units = "mm" ; TMI_CLOUD_WATER:flag = -999.999f ; float TMI_CLOUD_WATER_STD(time) ; TMI_CLOUD_WATER_STD:name = "TMI Liquid Cloud Water Standard Deviation" ; TMI_CLOUD_WATER_STD:units = "mm" ; TMI_CLOUD_WATER_STD:flag = -999.999f ; float TMI_RAIN_RATE(time) ; TMI_RAIN_RATE:name = "TMI Derived Radiometer Rain Rate" ; TMI_RAIN_RATE:units = "mm/hr" ; TMI_RAIN_RATE:flag = -999.999f ; float TMI_RAIN_RATE_STD(time) ; TMI_RAIN_RATE_STD:name = "TMI Derived Radiometer Rain Rate Standard Deviation" ; TMI_RAIN_RATE_STD:units = "mm/hr" ; TMI_RAIN_RATE_STD:flag = -999.999f ; float AVHRR_T55(time) ; AVHRR_T55:name = "AVHRR 0.55 micron Optical Depth" ; AVHRR_T55:units = "unitless" ; AVHRR_T55:flag = -999.999f ; float AVHRR_T55_STD(time) ; AVHRR_T55_STD:name = "AVHRR 0.55 micron Optical Depth Standard Deviation" ; AVHRR_T55_STD:units = "unitless" ; AVHRR_T55_STD:flag = -999.999f ; float AVHRR_T65(time) ; AVHRR_T65:name = "AVHRR 0.65 micron Optical Depth" ; AVHRR_T65:units = "unitless" ; AVHRR_T65:flag = -999.999f ; float AVHRR_T65_STD(time) ; AVHRR_T65_STD:name = "AVHRR 0.65 micron Optical Depth Standard Deviation" ; AVHRR_T65_STD:units = "unitless" ; AVHRR_T65_STD:flag = -999.999f ; float AVHRR_T80(time) ; AVHRR_T80:name = "AVHRR 0.80 micron Optical Depth" ; AVHRR_T80:units = "unitless" ; AVHRR_T80:flag = -999.999f ; float AVHRR_T80_STD(time) ; AVHRR_T80_STD:name = "AVHRR 0.80 micron Optical Depth Standard Deviation" ; AVHRR_T80_STD:units = "unitless" ; AVHRR_T80_STD:flag = -999.999f ; float AVHRR_T90(time) ; AVHRR_T90:name = "AVHRR 0.90 micron Optical Depth" ; AVHRR_T90:units = "unitless" ; AVHRR_T90:flag = -999.999f ; float AVHRR_T90_STD(time) ; AVHRR_T90_STD:name = "AVHRR 0.90 micron Optical Depth Standard Deviation" ; AVHRR_T90_STD:units = "unitless" ; AVHRR_T90_STD:flag = -999.999f ; 5.0 DATA REMARKS All data points represent averages over 10.0 second intervals centered at the indicated time. Gaps in the NFOV and AIMR data occur when the C-130 is not flying under "wings-level" conditions. Gaps in the TMI and AVHRR data occur when the satellite overpass does not include the C-130 flight track region. 6.0 REFERENCES More information and contact information for each of the data set is given below: C130 Contact: NCAR-RAF P.O. Box 3000 Boulder, CO 80307-3000x phone: 303-497-1030 NFOV Contact: Francisco P.J. Valero Atmospheric Research Laboratory Scripps Institution of Oceanography 9500 Gilman Dr., Dept. 0242 La Jolla, CA 92093-0242 Phone: 858-534-2701 FAX: 858-822-0517 Email: fvalero@ucsd.edu AIMR Contact: Craig Walther, Brian Lewis, or Rich Neitzel National Center For Atmospheric Research/ATD P.O. Box 3000 Boulder, Colorado 80303-3000 USA Phone: 303-497-2054 Email: craigw@ucar.edu TMI Contact: Remote Sensing Systems support@remss.com AVHRR Contact: James A. Coakley, Jr. College of Oceanic and Atmospheric Sciences Oregon State University Oceanography Admin 104 Corvallis, OR 97331-5503 USA Ph: (541) 737-5686 Fax: (541) 737-2540 E-mail: coakley@coas.oregonstate.edu