netcdf sgp1swfanalsirs1longE18.c1.20091106.125700 { dimensions: time = UNLIMITED ; // (623 currently) namelen = 64 ; variables: int base_time ; base_time:long_name = "Beginning Time of File" ; base_time:units = "seconds since 1970-01-01 00:00:00 00:00" ; base_time:calendar_date = "Year 2009 Month 11 Day 06 12:57:00" ; double time_offset(time) ; time_offset:long_name = "Time Offset from base_time" ; time_offset:units = "seconds" ; time_offset:comment = "none" ; int base_time_LST ; base_time_LST:long_name = "Beginning Time of File (LST)" ; base_time_LST:units = "seconds since 1970-01-01 00:00:00 00:00" ; base_time_LST:calendar_date = "Year 2009 Month 11 Day 06 06:57:00" ; base_time_LST:comment = "LST is based solely on longitude and does not include any politically-based adjustments." ; double time_offset_LST(time) ; time_offset_LST:long_name = "Time Offset from base_time_LST" ; time_offset_LST:units = "seconds" ; time_offset_LST:comment = "LST is based solely on longitude and does not include any politically-based adjustments." ; char site(namelen) ; site:long_name = "Site Identification" ; site:comment = "none" ; int coef_date ; coef_date:long_name = "Date (YYMMDD LST) for which the Coefficients are Applicable" ; coef_date:units = "unitless" ; coef_date:missing_value = "n/a" ; coef_date:comment = "Apart from a 6-digit date, the only other possible value here is 0. A 0 means that there are no daily coefficients for the data set; rather, one set of coefficients is applied to the entire data set. This possibility is certainly real for the tropics, where clear skies just do not occur frequently." ; float coef_clearsky_difratio_a ; coef_clearsky_difratio_a:long_name = "Clear-sky Fit Coefficient a to Diffuse Irradiance to Total Irradiance Ratio (DFRa)" ; coef_clearsky_difratio_a:units = "unitless" ; coef_clearsky_difratio_a:missing_value = "n/a" ; coef_clearsky_difratio_a:C_format = "%10.4f" ; coef_clearsky_difratio_a:FORTRAN_format = "F10.4" ; coef_clearsky_difratio_a:comment = "difratio(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_difratio_b ; coef_clearsky_difratio_b:long_name = "Clear-sky Fit Coefficient b to Diffuse Irradiance to Total Irradiance Ratio (DFRb)" ; coef_clearsky_difratio_b:units = "unitless" ; coef_clearsky_difratio_b:missing_value = "n/a " ; coef_clearsky_difratio_b:C_format = "%10.4f" ; coef_clearsky_difratio_b:FORTRAN_format = "F10.4" ; coef_clearsky_difratio_b:comment = "difratio(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_gsw_a ; coef_clearsky_gsw_a:long_name = "Clear-sky Fit Coefficient a to Global Shortwave Irradiance (CSWa)" ; coef_clearsky_gsw_a:units = "W/m^2" ; coef_clearsky_gsw_a:missing_value = "n/a" ; coef_clearsky_gsw_a:C_format = "%10.1f" ; coef_clearsky_gsw_a:FORTRAN_format = "F10.1" ; coef_clearsky_gsw_a:comment = "gsw_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_gsw_b ; coef_clearsky_gsw_b:long_name = "Clear-sky Fit Coefficient b to Global Shortwave Irradiance (CSWb)" ; coef_clearsky_gsw_b:units = "unitless" ; coef_clearsky_gsw_b:missing_value = "n/a" ; coef_clearsky_gsw_b:C_format = "%10.4f" ; coef_clearsky_gsw_b:FORTRAN_format = "F10.4" ; coef_clearsky_gsw_b:comment = "gsw_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_ssw_a ; coef_clearsky_ssw_a:long_name = "Clear-sky Fit Coefficient a to Summed Shortwave Irradiance (CSWa)" ; coef_clearsky_ssw_a:units = "W/m^2" ; coef_clearsky_ssw_a:missing_value = "n/a" ; coef_clearsky_ssw_a:C_format = "%10.1f" ; coef_clearsky_ssw_a:FORTRAN_format = "F10.1" ; coef_clearsky_ssw_a:comment = "ssw_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_ssw_b ; coef_clearsky_ssw_b:long_name = "Clear-sky Fit Coefficient b to Summed Shortwave Irradiance (CSWb)" ; coef_clearsky_ssw_b:units = "unitless" ; coef_clearsky_ssw_b:missing_value = "n/a" ; coef_clearsky_ssw_b:C_format = "%10.4f" ; coef_clearsky_ssw_b:FORTRAN_format = "F10.4" ; coef_clearsky_ssw_b:comment = "ssw_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_dsw_a ; coef_clearsky_dsw_a:long_name = "Clear-sky Fit Coefficient a to Global minus Summed Shortwave Irradiance Difference (SCORa)" ; coef_clearsky_dsw_a:units = "W/m^2" ; coef_clearsky_dsw_a:missing_value = " n/a" ; coef_clearsky_dsw_a:C_format = "%10.2f" ; coef_clearsky_dsw_a:FORTRAN_format = "F10.2" ; coef_clearsky_dsw_a:comment = "dsw_clearsky(CosZ)=a*(CosZ)**b + c (Z = solar zenith angle)." ; float coef_clearsky_dsw_b ; coef_clearsky_dsw_b:long_name = "Clear-sky Fit Coefficient b to Global minus Summed Shortwave Irradiance Difference (SCORb)" ; coef_clearsky_dsw_b:units = "unitless" ; coef_clearsky_dsw_b:missing_value = " n/a" ; coef_clearsky_dsw_b:C_format = "%10.4f" ; coef_clearsky_dsw_b:FORTRAN_format = "F10.4" ; coef_clearsky_dsw_b:comment = "dsw_clearsky(CosZ)=a*(CosZ)**b + c (Z = solar zenith angle)." ; float coef_clearsky_dsw_c ; coef_clearsky_dsw_c:long_name = "Clear-sky Offset Coefficient c for Global minus Summed Shortwave Irradiance Difference (SCORc)" ; coef_clearsky_dsw_c:units = "W/m^2" ; coef_clearsky_dsw_c:missing_value = " n/a" ; coef_clearsky_dsw_c:C_format = "%10.2f" ; coef_clearsky_dsw_c:FORTRAN_format = "F10.2" ; coef_clearsky_dsw_c:comment = "dsw_clearsky(CosZ)=a*(CosZ)**b + c (Z = solar zenith angle)." ; float coef_clearsky_albedo_a ; coef_clearsky_albedo_a:long_name = "Clear-sky Fit Coefficient a to Albedo (Alba)" ; coef_clearsky_albedo_a:units = "unitless" ; coef_clearsky_albedo_a:missing_value = "-9999.0" ; coef_clearsky_albedo_a:C_format = "%10.5f" ; coef_clearsky_albedo_a:FORTRAN_format = "F10.5" ; coef_clearsky_albedo_a:comment = "albedo_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_albedo_b ; coef_clearsky_albedo_b:long_name = "Clear-sky Fit Coefficient b to Albedo (Albb)" ; coef_clearsky_albedo_b:units = "unitless" ; coef_clearsky_albedo_b:missing_value = "-9999.0" ; coef_clearsky_albedo_b:C_format = "%10.5f" ; coef_clearsky_albedo_b:FORTRAN_format = "F10.5" ; coef_clearsky_albedo_b:comment = "albedo_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_guvb_a ; coef_clearsky_guvb_a:long_name = "Clear-sky Fit Coefficient a to Global UVB Irradiance (UVBa)" ; coef_clearsky_guvb_a:units = "unitless" ; coef_clearsky_guvb_a:missing_value = "-9999.0" ; coef_clearsky_guvb_a:C_format = "%10.5f" ; coef_clearsky_guvb_a:FORTRAN_format = "F10.5" ; coef_clearsky_guvb_a:comment = "guvb_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float coef_clearsky_guvb_b ; coef_clearsky_guvb_b:long_name = "Clear-sky Fit Coefficient b to Global UVB Irradiance (UVBb)" ; coef_clearsky_guvb_b:units = "unitless" ; coef_clearsky_guvb_b:missing_value = "-9999.0" ; coef_clearsky_guvb_b:C_format = "%10.5f" ; coef_clearsky_guvb_b:FORTRAN_format = "F10.5" ; coef_clearsky_guvb_b:comment = "guvb_clearsky(CosZ)=a*(CosZ)**b (Z = solar zenith angle)." ; float sun_earth_distance_dailyaverage ; sun_earth_distance_dailyaverage:long_name = "Daily Averaged Distance from the Earth to the Sun (auavg)" ; sun_earth_distance_dailyaverage:units = "Astronomical Units" ; sun_earth_distance_dailyaverage:missing_value = "n/a" ; sun_earth_distance_dailyaverage:C_format = "%10.5f" ; sun_earth_distance_dailyaverage:FORTRAN_format = "F10.5" ; sun_earth_distance_dailyaverage:comment = "Apart from a number close to 1, the only other possible value here is 0. A 0 means that an average earth sun distance for the data set is not meaningful and this occurs when coef_date is 0. This possibility is certainly real for the tropics, where clear skies just do not occur frequently. Note, however, that values for sun_earth_distance are still given below." ; short flag_clearsky_detection(time) ; flag_clearsky_detection:long_name = "Clear-sky Detection Flag (clrf)" ; flag_clearsky_detection:units = "unitless" ; flag_clearsky_detection:missing_value = "n/a" ; flag_clearsky_detection:comment = "0 => Measurement not classified as clear-sky, 1 => Measurement classified as clear-sky and used for the clear-sky fits." ; float solar_cos_z(time) ; solar_cos_z:long_name = "Cosine of the Solar Zenith Angle Z (CosZ)" ; solar_cos_z:units = "unitless" ; solar_cos_z:missing_value = "n/a" ; solar_cos_z:C_format = "%10.6f" ; solar_cos_z:FORTRAN_format = "F10.6" ; solar_cos_z:comment = "Used for the coefficient fits." ; float sun_earth_distance(time) ; sun_earth_distance:long_name = "Distance from the Earth to the Sun (au)" ; sun_earth_distance:units = "Astronomical Units" ; sun_earth_distance:missing_value = "n/a" ; sun_earth_distance:C_format = "%10.6f" ; sun_earth_distance:FORTRAN_format = "F10.6" ; sun_earth_distance:comment = "none" ; float gswfluxdn_measured(time) ; gswfluxdn_measured:long_name = "Measured Downwelling Global Shortwave Irradiance (gsw)" ; gswfluxdn_measured:units = "W/m^2" ; gswfluxdn_measured:missing_value = "-9999.0" ; gswfluxdn_measured:C_format = "%10.1f" ; gswfluxdn_measured:FORTRAN_format = "F10.1" ; gswfluxdn_measured:comment = "none" ; float gswfluxdn_clearskyfit(time) ; gswfluxdn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Global Shortwave Irradiance (csw)" ; gswfluxdn_clearskyfit:units = "W/m^2" ; gswfluxdn_clearskyfit:missing_value = "-9999.0" ; gswfluxdn_clearskyfit:C_format = "%10.1f" ; gswfluxdn_clearskyfit:FORTRAN_format = "F10.1" ; gswfluxdn_clearskyfit:comment = "none" ; float gswfluxdn_cloudeffect(time) ; gswfluxdn_cloudeffect:long_name = "Difference: gswfluxdn_measured - gswfluxdn_clearskyfit (gswfcg)" ; gswfluxdn_cloudeffect:units = "W/m^2" ; gswfluxdn_cloudeffect:missing_value = "-9999.0" ; gswfluxdn_cloudeffect:C_format = "%10.1f" ; gswfluxdn_cloudeffect:FORTRAN_format = "F10.1" ; gswfluxdn_cloudeffect:comment = "none" ; float difswfluxdn_measured(time) ; difswfluxdn_measured:long_name = "Measured Downwelling Diffuse Shortwave Irradiance (dif)" ; difswfluxdn_measured:units = "W/m^2" ; difswfluxdn_measured:missing_value = "-9999.0" ; difswfluxdn_measured:C_format = "%10.1f" ; difswfluxdn_measured:FORTRAN_format = "F10.1" ; difswfluxdn_measured:comment = "none" ; float difswfluxdn_clearskyfit(time) ; difswfluxdn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Diffuse Field Shortwave Irradiance (cdif)" ; difswfluxdn_clearskyfit:units = "W/m^2" ; difswfluxdn_clearskyfit:missing_value = "-9999.0" ; difswfluxdn_clearskyfit:C_format = "%10.1f" ; difswfluxdn_clearskyfit:FORTRAN_format = "F10.1" ; difswfluxdn_clearskyfit:comment = "none" ; float difswfluxdn_cloudeffect(time) ; difswfluxdn_cloudeffect:long_name = "Difference: difswfluxdn_measured - difswfluxdn_clearskyfit (diffcg)" ; difswfluxdn_cloudeffect:units = "W/m^2" ; difswfluxdn_cloudeffect:missing_value = "-9999.0" ; difswfluxdn_cloudeffect:C_format = "%10.1f" ; difswfluxdn_cloudeffect:FORTRAN_format = "F10.1" ; difswfluxdn_cloudeffect:comment = "none" ; float dirfluxdn_measured(time) ; dirfluxdn_measured:long_name = "Measured Downwelling Direct Shortwave Irradiance (dir)" ; dirfluxdn_measured:units = "W/m^2" ; dirfluxdn_measured:missing_value = "-9999.0" ; dirfluxdn_measured:C_format = "%10.1f" ; dirfluxdn_measured:FORTRAN_format = "F10.1" ; dirfluxdn_measured:comment = "This quantity is the pyrheliometer measurement times the cosine of the solar zenith angle." ; float dirfluxdn_clearskyfit(time) ; dirfluxdn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Direct Shortwave Irradiance (cdir)" ; dirfluxdn_clearskyfit:units = "W/m^2" ; dirfluxdn_clearskyfit:missing_value = "-9999.0" ; dirfluxdn_clearskyfit:C_format = "%10.1f" ; dirfluxdn_clearskyfit:FORTRAN_format = "F10.1" ; dirfluxdn_clearskyfit:comment = "This quantity is an estimate of the pyrheliometer measurement times the cosine of the solar zenith angle in the absence of clouds." ; float difratiodn_measured(time) ; difratiodn_measured:long_name = "Measured Downwelling Diffuse Irradiance to Downwelling Global Irradiance Ratio (difr)" ; difratiodn_measured:units = "unitless" ; difratiodn_measured:missing_value = "-9999.0" ; difratiodn_measured:C_format = "%10.5f" ; difratiodn_measured:FORTRAN_format = "F10.5" ; difratiodn_measured:comment = "none" ; float difratiodn_clearskyfit(time) ; difratiodn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Diffuse Irradiance to Downwelling Global Irradiance Ratio (cdifr)" ; difratiodn_clearskyfit:units = "unitless" ; difratiodn_clearskyfit:missing_value = "-9999.0" ; difratiodn_clearskyfit:C_format = "%10.5f" ; difratiodn_clearskyfit:FORTRAN_format = "F10.5" ; difratiodn_clearskyfit:comment = "none" ; float sswfluxdn_measured(time) ; sswfluxdn_measured:long_name = "Measured Downwelling Summed Shortwave Irradiance (dirfluxdn_measured+diffluxdn_measured) (ssw)" ; sswfluxdn_measured:units = "W/m^2" ; sswfluxdn_measured:missing_value = "-9999.0" ; sswfluxdn_measured:C_format = "%10.1f" ; sswfluxdn_measured:FORTRAN_format = "F10.1" ; sswfluxdn_measured:comment = "none" ; float sswfluxdn_clearskyfit(time) ; sswfluxdn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Summed Shortwave Irradiance (dirfluxdn_clearskyfit+diffluxdn_clearskyfit) (cssw)" ; sswfluxdn_clearskyfit:units = "W/m^2" ; sswfluxdn_clearskyfit:missing_value = "-9999.0" ; sswfluxdn_clearskyfit:C_format = "%10.1f" ; sswfluxdn_clearskyfit:FORTRAN_format = "F10.1" ; sswfluxdn_clearskyfit:comment = "none" ; float sswfluxdn_cloudeffect(time) ; sswfluxdn_cloudeffect:long_name = "Difference: sswfluxdn_measured - sswfluxdn_clearskyfit (sswfcg)" ; sswfluxdn_cloudeffect:units = "W/m^2" ; sswfluxdn_cloudeffect:missing_value = "-9999.0" ; sswfluxdn_cloudeffect:C_format = "%10.1f" ; sswfluxdn_cloudeffect:FORTRAN_format = "F10.1" ; sswfluxdn_cloudeffect:comment = "none" ; float albedosw_measured(time) ; albedosw_measured:long_name = "Measured Surface Albedo from Shortwave Irradiance Measurements (alb)" ; albedosw_measured:units = "unitless" ; albedosw_measured:missing_value = "-9999.0" ; albedosw_measured:C_format = "%10.5f" ; albedosw_measured:FORTRAN_format = "F10.5" ; albedosw_measured:comment = "Albedo value includes an upwelling diffuse shortwave irradiance measurement component." ; float albedosw_clearskyfit(time) ; albedosw_clearskyfit:long_name = "Clear-sky Fit Estimated Surface Albedo from Shortwave Irradiance Measurements (calb)" ; albedosw_clearskyfit:units = "unitless" ; albedosw_clearskyfit:missing_value = "-9999.0" ; albedosw_clearskyfit:C_format = "%10.5f" ; albedosw_clearskyfit:FORTRAN_format = "F10.5" ; albedosw_clearskyfit:comment = "Albedo value includes an upwelling diffuse shortwave irradiance measurement component." ; float guvbdn_measured(time) ; guvbdn_measured:long_name = "Measured Downwelling Global UVB Irradiance (uvb)" ; guvbdn_measured:units = "unitless" ; guvbdn_measured:missing_value = "-9999.0" ; guvbdn_measured:C_format = "%10.5f" ; guvbdn_measured:FORTRAN_format = "F10.5" ; guvbdn_measured:comment = " " ; float guvbdn_clearskyfit(time) ; guvbdn_clearskyfit:long_name = "Clear-sky Fit Estimated Downwelling Global UVB Irradiance (cguvb)" ; guvbdn_clearskyfit:units = "unitless" ; guvbdn_clearskyfit:missing_value = "-9999.0" ; guvbdn_clearskyfit:C_format = "%10.5f" ; guvbdn_clearskyfit:FORTRAN_format = "F10.5" ; guvbdn_clearskyfit:comment = " " ; short qc_gswfluxdn(time) ; qc_gswfluxdn:long_name = "Quality Control Flags for Downwelling Global Shortwave Irradiance (gflg)" ; qc_gswfluxdn:qcflagdefine = "0 => Data is problem free, 1 => gswfluxdn_measured < -20.0 W/m^2 (Bad data), 2 => gswfluxdn_measured > 1500 W/m^2 (Bad data)" ; short qc_difswfluxdn(time) ; qc_difswfluxdn:long_name = "Quality Control Flags for Downwelling Diffuse Shortwave Irradiance (difflg)" ; qc_difswfluxdn:qcflagdefine = "0 => Data is problem free, 1 => difswfluxdn_measured < -20.0 W/m^2 (Bad data), 2 => Absolute difference between gswfluxdn_measured and sswfluxdn_measured is greater than 100 W/m^2 (Bad data), 9 => Downwelling diffuse shortwave irradiance estimated from the difference gswfluxdn_measured - dirfluxdn_measured." ; short qc_dirswfluxdn(time) ; qc_dirswfluxdn:long_name = "Quality Control Flags for Downwelling Direct Shortwave Irradiance (dirflg)" ; qc_dirswfluxdn:qcflagdefine = "-9 => Measured data is sufficiently bad that there are no data at this time, 0 => Data is problem free, 1 => Measured data is bad, so dirfluxdn_measured is estimated by the difference gswfluxdn_measured - difswfluxdn_measured." ; short qc_sswfluxdn(time) ; qc_sswfluxdn:long_name = "Quality Control Flags for Downwelling Summed Shortwave Irradiance (sflg)" ; qc_sswfluxdn:qcflagdefine = "-4 => CosZ > 0.12, gswfluxdn_measured/gswfluxdn_clearskyfit > 0.9 AND difswfluxdn_measured/gswfluxdn_measured > 0.9, -3 => CosZ > 0.09, |gswfluxdn_measured/gswfluxdn_clearskyfit - sswfluxdn_measured/sswfluxdn_clearskyfit| > 2*swrlim, -2 => CosZ > 0.25, |gswfluxdn_measured/gswfluxdn_clearskyfit - sswfluxdn_measured/sswfluxdn_clearskyfit| > swrlim, -1 => Direct or diffuse irradiance data is bad, no estimate possible, 0 => Data is problem free, 1 => The flux sswfluxdn_measured is estimated from the equation sswfluxdn_measured = (gswfluxdn_measured - [SCORa*(CosZ)**SCORb + SCORc]*[gswfluxdn_measured/gswfluxdn_clearskyfit]) since some of the required measurement data is bad. The -2 and -3 tests detect when one of either the direct or diffuse is bad data. The -4 tests detect when the whole tracker was off, i.e., the Sum is about equal to TSW because the Diffuse is unshaded. The threshold swrlim can be determined by inspection of the data for which the corresponding flag value occurs." ; float lat ; lat:long_name = "north latitude" ; lat:units = "degrees" ; lat:valid_range = -90.f, 90.f ; lat:C_format = "%7.3f" ; lat:FORTRAN_format = "F7.3" ; lat:comment = "none" ; float lon ; lon:long_name = "east longitude" ; lon:units = "degrees" ; lon:valid_range = -180.f, 180.f ; lon:C_format = "%8.3f" ; lon:FORTRAN_format = "F8.3" ; lon:comment = "none" ; float alt ; alt:long_name = "altitude" ; alt:units = "meters above Mean Sea Level" ; alt:C_format = "%6.1f" ; alt:FORTRAN_format = "F6.1" ; alt:comment = "none" ; // global attributes: :Date = "Tue Feb 02 23:33:28 GMT 2010" ; :Fitmode = "01" ; :Version = "$State: vap-swfanal1long-3.10-0.sol5_10 $" ; :Number_Input_Platforms = "1" ; :Input_Platforms = "sgpsirsE18.b1" ; :Input_Platforms_Versions = "7.0" ; :zeb_platform = "sgp1swfanalsirs1longE18.c1" ; :Command_Line = "swfanal1long -s YYYYMMDD -e YYYYMMDD SITE QCFILE ZIPPING" ; :contact = "Algorithm Originator: Dr. Charles N. Long" ; :comment = "fitmode=01 indicates a daily fit, fitmode=00 indicates a 1-fit" ; }