[CF-metadata] new standard name: total_totals_index

From: Jonathan Gregory <j.m.gregory>
Date: Sat, 18 May 2013 15:06:46 +0100

r Jonathan

> total_totals_index
>
> with the associated definition:
>
> The Total Totals Index (TT) indicates the likelihood of severe
> convection. The index is derived from the difference in air
> temperature between 850 and 500 hPa (the vertical totals) and the
> difference between the dew point temperature at 850 hPa and the air
> temperature at 500 hPa (the cross totals). The vertical totals and
> cross totals are summed to obtain the Total Totals Index.

This term is not self-explanatory and presents the same kind of difficulty as
"lifted index" (see my last email). In this case, however, it seems impossible
to devise a short definition. Moreover, unlike lifted index, it is not a
quantity applicable to any level; the two levels concerned are hard-wired into
the definition. It's a one-off ad-hoc empirical quantity.

As a standard name, it would be good if we could add some context to it. For
instance, what about

atmosphere_stability_total_totals_index

If I have understood the definitions online and yours above, this quantity is
actually not a dimensionless index. Its unit is K, because it is calculated by
adding temperature differences.

Best wishes

Jonathan
Received on Sat May 18 2013 - 08:06:46 BST