All,
This particular example has confused me in the past but for a different
reason. It seems to me like the time values are not the best choice to
represent the climatological time intervals.
i.e. instead of:
> time="1960-4-16", "1960-7-16", "1960-10-16", "1961-1-16" ;
> climatology_bounds="1960-3-1", "1990-6-1",
> "1960-6-1", "1990-9-1",
> "1960-9-1", "1990-12-1",
> "1960-12-1", "1991-3-1" ;
I think it would be better to have the time values as the midpoint of the
bounds. i.e.
time="1975-4-16", "1975-7-16", "1975-10-16", "1976-1-16" ;
climatology_bounds="1960-3-1", "1990-6-1",
"1960-6-1", "1990-9-1",
"1960-9-1", "1990-12-1",
"1960-12-1", "1991-3-1" ;
This corresponds better with the recomendation given in section 7.4 which
states:
"The time coordinates should be values that are representative of the
climatological time intervals, such that an application which does not
recognise climatological time will nonetheless be able to make a reasonable
interpretation. "
And also corresponds with the example in section 7.7 which is as follows:
time="1965-1-15", "1975-1-15", "1985-1-15" ;
climatology_bounds="1961-1-1", "1970-2-1",
"1971-1-1", "1980-2-1",
"1981-1-1", "1990-2-1" ;
Regards,
Dominic Lowe
On Friday 03 July 2009 09:24:54 Heinke Hoeck wrote:
> Dear all,
>
> I need help for 'Example 7.8. Climatological seasons'.
> This should be:
> 'average seasonal-minimum temperature for the four standard
> climatological seasons MAM JJA SON DJF'.
>
> dimensions:
> time=4;
> nv=2;
> variables:
> float temperature(time,lat,lon);
> temperature:long_name="surface air temperature";
> temperature:cell_methods="time: minimum within years time: mean over
> years";
> temperature:units="K";
> double time(time);
> time:climatology="climatology_bounds";
> time:units="days since 1960-1-1";
> double climatology_bounds(time,nv);
> data: // time coordinates translated to date/time format
> time="1960-4-16", "1960-7-16", "1960-10-16", "1961-1-16" ;
> climatology_bounds="1960-3-1", "1990-6-1",
> "1960-6-1", "1990-9-1",
> "1960-9-1", "1990-12-1",
> "1960-12-1", "1991-3-1" ;
>
> Where is the information that the intervals are 3 months (seasons)?
> In the climatology_bounds the intervals are 30 years and 3 months.
> In the cell_methods no interval information is given.
>
> Best wishes
> Heinke
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Received on Tue Jul 07 2009 - 03:10:52 BST
