Dear Alejandro and Jonathan, I would like to remind you of my recent proposal for Emissivity as below.
Young-In -----Original Message----- From: Won, Young-In (GSFC-610.2)[RSIS] Sent: Monday, February 02, 2009 7:21 PM To: 'Jonathan Gregory'; '[email protected]' Subject: RE: [CF-metadata] Emissivity not found in the current standard nametable Dear All, I would like to propose two (three for the dimension) new standard names as follows. 1. name: surface_longwave_emissivity canonical unit: 1 ( unitless number between 0 and 1) definition: The ratio of energy radiated by the Earth's surface to energy radiated by a black body at the same temperature in longwave region. 2. surface_mircrowave_emissivity canonical unit: 1 ( unitless number between 0 and 1) definition: The ratio of energy radiated by the Earth's surface to energy radiated by a black body at the same temperature in microwave frequency region. 3. name: radiation_frequency (alias: electromagnetic_frequency) canonical unit: hertz; definition: The radiation frequency can refer to any electromagnetic frequency, such as light, heat radiation and radio waves (copied and modified from "radiation_wavelength". I need "radiaton_frequency" because the emissivity in our data set is given at specific frequency). ---------------------------------------------------- Young-In Won, Ph.D. NASA Goddard Space Flight Center Mail stop: 610.2 Greenbelt, MD 20771 (301) 614 6749 (O) (301) 614 5268 (F) [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jonathan Gregory Sent: Wednesday, February 11, 2009 2:20 PM To: Alejandro Bodas-Salcedo Cc: [email protected]; Sandrine Bony; Webb, Mark Subject: [CF-metadata] Proposal for new standard names Dear Alejandro > height_of_full_levels_above_reference_ellipsoid [m] > height_of_half_levels_above_reference_ellipsoid [m] standard names do not indicate coordinate variables, so the standard name for these is height_above_reference_ellipsoid, which is already in the table, and the variable should have a vertical coordinate variable of model_level_number. > air_pressure_at_full_levels [Pa] > air_pressure_at_half_levels [Pa] Likewise. The standard name is air_pressure. > b) Cloud condensate mixing ratios [1] > mixing_ratio_large_scale_cloud_liquid > mixing_ratio_large_scale_cloud_ice > mixing_ratio_convective_cloud_liquid > mixing_ratio_convective_cloud_ice > mixing_ratio_of_ozone_in_air [1] Are these the same as mass_fraction_of_stratiform_cloud_liquid_water_in_air mass_fraction_of_stratiform_cloud_ice_in_air mass_fraction_of_convective_cloud_liquid_water_in_air mass_fraction_of_convective_cloud_ice_in_air mass_fraction_of_ozone_in_air which are in the table, or are you intending to draw a precise distinction between mixing_ratio and mass_fraction? There have been lengthy discussions on the email list with the outcome that a distinction is not made except for the case of water vapour in air. > d) Radiative properties of clouds. Optical depths at 0.67 micron and > emissivities at 10.5 micron. The wavelengths should be specified with a scalar coordinate variable of radiation_wavelength. > large_scale_cloud_optical_depth [1] > convective_cloud_optical_depth [1] For consistency with the existing optical depth standard names, I suggest these should be atmosphere_optical_thickness_due_to_large_scale|convective_cloud > large_scale_cloud_emissivity [1] > convective_cloud_emissivity [1] If the variable does specify the wavelength, I think it is OK just to say emissivity. Young-In Wong has recently proposed surface_longwave_emissivity, which does not specify a precise wavelength. > e) Surface variables. Emissivity at 10.5 micron. > skin_temperature [K] The variable called surface_temperature is the temperature at the interface. Is that what you mean? > h) Cloud fractions from CALIPSO/CLOUDSAT simulators. Units: 1. > calipso_total_cloud_fraction Should be calipso_cloud_area_fraction like isccp_cloud_area_fraction (but see also below). > calipso_low_level_cloud_fraction > calipso_mid_level_cloud_fraction > calipso_high_level_cloud_fraction I'd say low, mid and high are coordinates. They should be specified as coordinate variables, rather than in the standard name. We have not so far named cloud layers in this way. > calipso_cloud_fraction > calipsonocloudsat_cloud_fraction > calipso_and_cloudsat_total_cloud_fraction I'm not sure what these mean. > i.1 CloudSat Radar Reflectivity Factor (94 GHz) > cloudsat_radar_reflectivity_94 [dBZ] The frequency should be specified as a scalar coordinate variable of radiation_frequency, which is not in the table at present but could be proposed. The name can then be just cloudsat_radar_reflectivity. Is it necessary to name "cloudsat" in this? I tend to think it would be better to be more generic i.e. just radar_reflectivity. > i.2 CALIPSO Lidar Attenuated Total Backscatter (532 nm) > calipso_atb_532 [1] Again, the wavelength is a coordinate and should not be in the name. Could "total" be omitted? Usually we assume that unqualified concepts are inclusive. Thus lidar_attenuated_backscatter But I'm not familiar with this so I don't know what the relationship is between this quantity and the next one > calipso_molecular_backscatter_532 [m-1 sr-1] Perhaps you or someone else could clarify. As they don't have the same units the names should distinguish them more. Are they analogous to these quantities in the table? surface_backwards_scattering_coefficient_of_radar_wave: 1 volume_backwards_scattering_coefficient_of_radiative_flux_in_sea_water:m -1 volume_scattering_coefficient_of_radiative_flux_in_sea_water:m-1 volume_scattering_function_of_radiative_flux_in_sea_water:m-1 sr-1 If so, similar names should be adopted. > k) Outputs from ISCCP simulator. Units are [1] otherwise stated. > isccp_total_cloud_area_fraction We already have isccp_cloud_area_fraction > isccp_mean_cloud_albedo Could this be simply cloud_albedo > isccp_mean_cloud_top_pressure [Pa] air_pressure_at_cloud_top is already in the table. > isccp_mean_brightness_temperature_assuming_clear_sky [K] > isccp_mean_brightness_temperature [K] > isccp_mean_optical_depth With these variables, is isccp necessary? Standard names are intended to name geophysical quantities. If ISCCP is estimating geophysical quantities, they do not need isccp in their names. For instance, we don't have a quantity called hadisst_sea_surface_temperature. The quantity is just SST, and HadISST is one estimate of it. ISCCP could be identified in one of the global attributes of the file. I am not sure why we included a standard name for ISCCP cloud area fraction and whether we should do so for CALIPSO or this one > misr_cloud_area_fraction > > m) PARASOL-like mono-directional reflectance. Units: 1. > parasol_reflectance Could you explain what that means? Best wishes Jonathan _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
