Hello all -
I'd been hoping that I would not outlive my ability to ignore the CF
FeatureTypes,
but apparently it's not to be. As a fallback position, now I'm hoping
that we can
add a type, to accommodate data collected on stationary moorings, where
there
are time series of variables at a single x,y location, at multiple
depths, on a single
time base. The majority of the data in the OceanSITES project fits into
this category,
and there is no existing feature type to describe it, as far as I
understand.
Presently, to use any of the feature types, we would need to store data
from each
depth in an individual file. This is a serious problem, in part because
we have
dozens of instruments - 30 or 40 in some cases - on each mooring, but also
because, for most of our data users, the most convenient files contain
z-merged
data; for example, a single time series containing all the temperatures
and salinities.
Back in 2009, I made the suggestion to change the list of types that
cover time series,
from the single:
* stationTimeSeries: a time-series of data points at the same
location, with varying time
to the pair:
* TimeSeries: a time-series of data points at one X,Y,Z with varying T
* stationTimeSeries: a time-series of data points at one X,Y, with
multiple Z and T
or, alternatively,to change the definition of stationTimeSeries to
something like 'a
time-series of data points at one geographical location and one or more
depths'.
The exact terms don't matter much to me (although there's a cultural problem
with including the word 'profile' in the name of a 2D timeseries) but we
still DO
need a way to describe these stations.
Here's an excerpt from a CDL for a typical moored station's data.
dimensions:
TIME = 129139 ;
DEPTH = 16 ;
LATITUDE = 1 ;
LONGITUDE = 1 ;
variables:
double TIME(TIME) ;
TIME:standard_name = "time" ;
double DEPTH(DEPTH) ;;
DEPTH:standard_name = "depth" ;
double LATITUDE(LATITUDE) ;
LATITUDE:standard_name = "latitude" ;
double LONGITUDE(LONGITUDE) ;
LONGITUDE:standard_name = "longitude" ;
double TEMP(TIME, DEPTH) ;
TEMP:standard_name = "sea_water_temperature" ;
TEMP:coordinates = "TIME, DEPTH, LATITUDE, LONGITUDE" ;
There are several threads in the CF mail archive about this, mostly
under subject lines containing the phrase 'point obs' - but as far
as I know, it was never resolved, at least not to the satisfaction of
those who work with mooring data.
Regards -
Nan
--
*******************************************************
* Nan Galbraith Information Systems Specailist *
* Upper Ocean Processes Group Mail Stop 29 *
* Woods Hole Oceanographic Institution *
* Woods Hole, MA 02543 (508) 289-2444 *
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Received on Tue Feb 28 2012 - 13:33:53 GMT