Dear Olivier, Thank you for your proposals. I have some comments/questions (please see below).
> tendency_of_global_average_sea_level_change (m/year) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. "tendency_of_X" means > derivative of X with respect to time. This name looks fine and is clearly related to the existing name global_average_sea_level_change. The units of m/year are sensible. We have used time units of years for one or two other names such as age_of_sea_ice. We should add the standard text for 'tendency' to the definition, i.e., ' "tendency_of_X" means derivative of X with respect to time.' > tendency_of_local_average_sea_level_change (m/year) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. Local means the > quantity is depicted locally. "tendency_of_X" means derivative of X with > respect to time. This name looks fine. The units are OK. Again we need to add text to the definition regarding 'tendency'. By 'local' I assume you mean any area that is less than global and this would need to be indicated by adding bounds on the horizontal coordinate variables, or perhaps by using a coordinate variable with a standard name of 'region' if the area is something like the North Atlantic. We should add some explanatory text to the definition. Is this OK? > global_average_sea_level_change_annual_amplitude (m) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. > global_average_sea_level_change_semiannual_amplitude (m) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. I wonder, do we really need "annual" and "semiannual" in the names? Presumably the date to which the amplitude applies would need to be specified by a time coordinate variable or scalar variable with bounds to indicate the averaging period. Couldn't we then have a general name of global_average_sea_level_change_amplitude without the need to specify annual or semiannual separately? > global_average_sea_level_change_annual_phase (degree) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. > global_average_sea_level_change_semiannual_phase (degree) > Global average sea level change is due to change in volume of the water in > the ocean, caused by mass > and/or density change, or to change in the volume of the ocean basins, caused > by tectonics etc. It is > sometimes called "eustatic", which is a term that also has other definitions. > It differs from the change > in the global average sea surface height relative to the centre of the Earth > by the global average > vertical movement of the ocean floor. Zero sea level change is an arbitrary > level. I'm not sure I understand what the phase quantities are. Do they indicate a seasonal cycle in sea level change? What is the datum for measuring the phase (i.e., what would a phase of zero degrees mean)? Also, as for the amplitude names, I wonder if we need separate 'annual' and 'semiannual' names for the phases? Best wishes, Alison > Thanks for your comments! > > Best wishes > > Olivier. > > > > Olivier Lauret > Project Engineer > Satellite Oceanography Division > > E-mail: [email protected] > Tel. +33 561 394 851; Fax +33 561 393 782 ------ Alison Pamment Tel: +44 1235 778065 NCAS/British Atmospheric Data Centre Email: [email protected] STFC Rutherford Appleton Laboratory R25, 2.22 Harwell Oxford, Didcot, OX11 0QX, U.K. -- Scanned by iCritical. _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
