[CF-metadata] MSG Cloud physical properties codification

From: Jonathan Gregory <j.m.gregory>
Date: Tue, 23 Nov 2010 20:22:07 +0000

Dear Maarten

Thank you for working towards CF compliance.

> - instrument_zenith_angle (degree): "Instrument zenith angle is the the
> angle between the line of sight to the instrument and the local vertical" ;
There was a recent thread on this email list about names similar to this and
maybe this has already come up - I don't remember. Possibly it would be better
to make it
  platform_zenith_angle
because there are various other platform_ standard names. Would that be OK?

> - solar_instrument_relative_azimuth_angle (degree): "The difference
> between the solar azimuth angle and the instrument azimuth angle" ;
Personally I would find that a bit hard to understand. Also, I wonder if a
sign convention should be specified. To address that, what would your opinion
be of
  angle_of_rotation_from_solar_azimuth_to_platform_azimuth
based on existing names of the form angle_of_rotation_from_A_to_B.

> - thermodynamic_particle_phase_at_cloud_top (status_flag): "The
> thermodynamic phase of particles at the top of the cloud" ;
What are the allowed values of this quantity?

> Is there a better way do distuingish between
> thermodynamic_particle_phase_at_cloud_top and
> thermodynamic_particle_phase_at_cloud_top_infrared?
There are other instances where we have used a phrase defined_by to make
a distinction between closely related geophysical concepts. Is this such a
case, where "cloud top" is defined in particular ways? What are these ways?

> - geometrical_thickness_of_liquid_water_cloud (m): "Cloud Geometrical
> Thickness (cloud top height minus cloud base)" ;
Could we omit "geometrical"? In standard names, "thickness" means just this
i.e. the vertical extent of a layer.

> - effective_radius_of_cloud_condensed_water_particle_at_cloud_top (m):
> "Particle effective radius for both liquid and ice water particles" ;
That one seems to correspond well to the pattern of some existing names.

Best wishes

Jonathan
Received on Tue Nov 23 2010 - 13:22:07 GMT