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Greetings all,A few of us here at RSS took a look at your new names and offer some thoughts:
1. For the platform and sensor look angle as written, nadir is defined as pointing towards the center of the Earth. We question whether this is appropriate for all cases, as many satellites are flown with nadir pointing toward the closest place on Earth, so that the nadir look has an incidence angle of 0. (geodetic vs. geocentric pointing). We suggest separate geodetic and geocentric look angle definitions to reduce confusion, such as sensor_look_angle_geocentric and sensor_look_angle_geodetic.
2. There is only a linear_term_of_spectral_radiance_correction_due_to_intercalibration and a constant_term_of_spectral_radiance_correction_due_to_intercalibration. Many microwave radiometers have quadratic (or higher order) terms in the calibration and subsequent calibration corrections. We suggest adding more names.
3. Azimuth angle definitions need to be clearer (see suggested changes in bold below). We would like to be sure that the definition is unambiguous. For example, the definition of platform_azimuth_angle would be clearer if it read: "platform" refers to the vehicle from which observations are made e.g. airplane, ship, or satellite. Platform azimuth angle is the horizontal angle between the line of sight *from the observation point *to the platform and a reference direction *at the observation point,* which is often due north. The angle is measured clockwise*starting from the reference direction*.
4. The definition for sensor_band_central_wavenumber does not say whether the first moment of the band's normalized spectral response function is averaged over wavelength or frequency. One can't invert wavelength and wavenumber if not calculated correctly.
Thanks for taking these points into consideration. Significant input came from Carl Mears and Kyle Hilburn at RSS.
-Deborah -- Deborah K Smith Scientist Remote Sensing Systems smith@xxxxxxxxx www.remss.com www.discover-earth.org
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