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    <p>Nan,</p>
    <p>That's another good point to keep in mind. Most DOY (Day Of Year)
      representations that I have seen are 1-based. Everything to do
      with calendars and/or time always seems to get complicated!</p>
    <p>Jim<br>
    </p>
    <br>
    <div class="moz-cite-prefix">On 3/17/17 9:05 AM, Nan Galbraith
      wrote:<br>
    </div>
    <blockquote cite="mid:260a6523-a923-2d58-effe-5024c0a7465b@whoi.edu"
      type="cite">We use the term yearday; even this is imprecise,
      because it can be calculated
      <br>
      at least 2 different ways.
      <br>
      <br>
      We always include a reference to (and definition of) the Naval
      yearday convention,
      <br>
      which defines noon on January 1 as yearday 1.5, not 0.5.
      <br>
      <br>
      For time series data that we publish (to OceanSITES, mainly) we
      use the 'normal'
      <br>
      CF "days since 1950-01-01 00:00:00", but for climatology data and
      other internal
      <br>
      data, we use whatever is convenient.
      <br>
      <br>
      Cheers - Nan
      <br>
      <br>
      <br>
      On 3/16/17 4:48 PM, Dave Allured - NOAA Affiliate wrote:
      <br>
      <blockquote type="cite">Here is a credible appeal to avoid the
        terms Julian Date and Julian Day in any scientific usage, to
        mean Day of Year. Citing document MODIFIED JULIAN DATE, M. R.
        Winkler, formerly with U.S. Naval Observatory:
        <br>
        <br>
        <a class="moz-txt-link-freetext" href="http://tycho.usno.navy.mil/mjd.html">http://tycho.usno.navy.mil/mjd.html</a>
        <br>
        <br>
        """ The MJD (and even more so the JD) has to be well
        distinguished from this day of the year (DOY). This is also
        often but erroneously called Julian Date, when in fact it is a
        Gregorian Date expressed as number of days in the year. This is
        a grossly misleading practice that was introduced by some who
        were simply ignorant and too careless to learn the proper
        terminology. It creates a confusion which should not be taken
        lightly. Moreover, a continuation of the use of expressions
        "Julian" or "J" day in the sense of a Gregorian Date will make
        matters even worse. It will inevitably lead to dangerous
        mistakes, increased confusion, and it will eventually destroy
        whatever standard practices exist. """
        <br>
        <br>
        Though I also have used these terms in the past, I now agree
        with this opinion.  I would suggest that CF Conventions should
        use only Day of Year (DOY) or some similar term for this
        purpose.
        <br>
        <br>
        --Dave
        <br>
        <br>
        <br>
        On Thu, Mar 16, 2017 at 1:56 PM, Roy Mendelssohn - NOAA Federal
        <<a class="moz-txt-link-abbreviated" href="mailto:roy.mendelssohn@noaa.gov">roy.mendelssohn@noaa.gov</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:roy.mendelssohn@noaa.gov"><mailto:roy.mendelssohn@noaa.gov></a>> wrote:
        <br>
        <br>
            Julian day is used in several different ways,  as John says:
        <br>
        <br>
            <a class="moz-txt-link-freetext" href="https://landweb.modaps.eosdis.nasa.gov/browse/calendar.html">https://landweb.modaps.eosdis.nasa.gov/browse/calendar.html</a>
        <br>
           
        <a class="moz-txt-link-rfc2396E" href="https://landweb.modaps.eosdis.nasa.gov/browse/calendar.html"><https://landweb.modaps.eosdis.nasa.gov/browse/calendar.html></a>
        <br>
        <br>
            -Roy
        <br>
        <br>
            > On Mar 16, 2017, at 12:49 PM, John Helly
        <<a class="moz-txt-link-abbreviated" href="mailto:hellyj@ucsd.edu">hellyj@ucsd.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:hellyj@ucsd.edu"><mailto:hellyj@ucsd.edu></a>> wrote:
        <br>
            >
        <br>
            > In language, definitions are based on usage. Julian
        date, modulo
        <br>
            the year, is a convention that I have been using for decades
        to do
        <br>
            what you are talking about but I defer to wiser minds.
        <br>
            >
        <br>
            > J.
        <br>
            >
        <br>
            > On 3/16/17 9:42 AM, Jim Biard wrote:
        <br>
            >> John,
        <br>
            >>
        <br>
            >> As best as I understand it, Julian day is a term
        that is
        <br>
            grossly misused. Julian Day is defined as the elapsed days
        since
        <br>
            January 1, 4713 BCE. Lots of people use the term to refer to
        <br>
            day-in-year, but this doesn't seem to be a proper usage.
        <br>
            >>
        <br>
            >> Grace and peace,
        <br>
            >>
        <br>
            >> Jim
        <br>
            >>
        <br>
            >> On 3/16/17 3:36 PM, John Helly wrote:
        <br>
            >>> Sorry to jump in here but isn't this just the
        Julian day?
        <br>
            >>>
        <br>
            >>> J.
        <br>
            >>>
        <br>
            >>>
        <br>
            >>> On 3/16/17 8:24 AM, Nan Galbraith wrote:
        <br>
            >>>> I agree that there's a lot of interest, and
        I have 2 questions.
        <br>
            >>>>
        <br>
            >>>> To make the data most useful, shouldn't the
        time coordinate
        <br>
            variable be
        <br>
            >>>> Jan 1, and shouldn't the 'days since'
        (data) variable
        <br>
            represent the yearday
        <br>
            >>>> within that year?
        <br>
            >>>>
        <br>
            >>>> My specific concerns with Jim's approach:
        <br>
            >>>>
        <br>
            >>>> first_freeze_date:units = "days since
        1900-01-01 00:00:00"      - This doesn't seem
        <br>
            >>>> to me to provide the most easily used data
        point, wouldn't
        <br>
            the year-day be more
        <br>
            >>>> convenient, for seeing how this value
        varies over the years?
        <br>
            >>>>
        <br>
            >>>> And with Antoio's:
        <br>
            >>>>
        <br>
            >>>> first_freeze_date:coordinates="threshold
        time"; - I don't see
        <br>
            how threshold,
        <br>
            >>>> which is a temperature, can be a coordinate
        of this variable.
        <br>
            Also, I'd like to know
        <br>
            >>>> why setting   time:units="days since
        2000-6-1"; is preferable
        <br>
            to using 2000-1-1;
        <br>
            >>>> doesn't this invite errors in using the
        time in applications
        <br>
            like matlab and python?
        <br>
            >>>>
        <br>
            >>>> Actually, the metadata doesn't tell me how
        to interpret the
        <br>
            values in first_freeze_date -
        <br>
            >>>> the short name implies that they're dates,
        the units implies
        <br>
            they're elapsed days, but
        <br>
            >>>> without a reference date to enable
        decoding.
        <br>
            >>>>
        <br>
            >>>> Cheers - Nan
        <br>
            >>>>
        <br>
            >>>>
        <br>
            >>>> On 3/16/17 8:45 AM, Jim Biard wrote:
        <br>
            >>>>>
        <br>
            >>>>> Hi.
        <br>
            >>>>>
        <br>
            >>>>> There is clearly interest here! I agree
        that day_in_year is
        <br>
            rather generic, and there should probably be a more precise
        term.
        <br>
            I'm not so sure about the cell_methods that were suggested
        below.
        <br>
            In my particular case the values are derived from a daily
        Tmin
        <br>
            product. Each value is the date of the first Tmin < 0 C
        within the
        <br>
            time bounds. If it was a spell length, such as growing
        season
        <br>
            length, then I can see the need for a more climatological
        cell_method.
        <br>
            >>>>>
        <br>
            >>>>> We can keep this up and work up some
        standard_name
        <br>
            definitions to propose. I'm sure the results will be better
        if we
        <br>
            collaborate compared to what I'd do on my own.
        <br>
            >>>>>
        <br>
            >>>>> Grace and peace,
        <br>
            >>>>>
        <br>
            >>>>> Jim
        <br>
            >>>>>
        <br>
            >>>>>
        <br>
            >>>>> On 3/16/17 7:23 AM, Antonio S. Cofi�o
        wrote:
        <br>
            >>>>>> Dear all,
        <br>
            >>>>>> There is no standard_name for the
        concept but there are 2
        <br>
            different ones which delimit the approach that it could be
        used as
        <br>
            templates for the new one:
        <br>
            >>>>>>
        *time_when_flood_water_falls_below_threshold
        <br>
            *(time_when_flood_water_rises_above_threshold and
        <br>
            time_of_maximum_flood_depth are also good examples )
        <br>
            >>>>>>
        <br>
           
<a class="moz-txt-link-freetext" href="http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#time_when_flood_water_falls_below_threshold_tr">http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#time_when_flood_water_falls_below_threshold_tr</a><br>
           
<a class="moz-txt-link-rfc2396E" href="http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#time_when_flood_water_falls_below_threshold_tr"><http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#time_when_flood_water_falls_below_threshold_tr></a><br>
            >>>>>>> The quantity with standard name
        <br>
            *time_when_flood_water_falls_below_threshold*: is the time
        elapsed
        <br>
            between the breaking of a levee (origin of flood water
        simulation)
        <br>
            and the instant when the depth falls below a given threshold
        for
        <br>
            the last time, having already risen to its maximum depth, at
        a
        <br>
            given point in space. If a threshold is supplied, it should
        be
        <br>
            specified by associating a coordinate variable or scalar
        <br>
            coordinate variable with the data variable and giving the
        <br>
            coordinate variable a standard name of
        flood_water_thickness. The
        <br>
            values of the coordinate variable are the threshold values
        for the
        <br>
            corresponding subarrays of the data variable. If no
        threshold is
        <br>
            specified, its value is taken to be zero. Flood water is
        water
        <br>
            that covers land which is normally not covered by water.
        <br>
            >>>>>> the problem is the event
        definition, which is quite
        <br>
            different to the one it's been considered here which is more
        like
        <br>
            a climatological statistics. The good thing is the CF
        already has
        <br>
            some good definitions for those climatological statistics,
        like
        <br>
            Example 7.11 on CF1.6 document:
        <br>
            >>>>>>
        <br>
           
<a class="moz-txt-link-freetext" href="http://cfconventions.org/cf-conventions/v1.6.0/cf-conventions.html#extreme-statistics-and-spell-lengths-ex">http://cfconventions.org/cf-conventions/v1.6.0/cf-conventions.html#extreme-statistics-and-spell-lengths-ex</a><br>
           
<a class="moz-txt-link-rfc2396E" href="http://cfconventions.org/cf-conventions/v1.6.0/cf-conventions.html#extreme-statistics-and-spell-lengths-ex"><http://cfconventions.org/cf-conventions/v1.6.0/cf-conventions.html#extreme-statistics-and-spell-lengths-ex></a><br>
            >>>>>>
        <br>
            >>>>>> And more convenient definition of
        this climatological
        <br>
            statistics could be:
        <br>
            >>>>>>
        <br>
           
<a class="moz-txt-link-freetext" href="http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#spell_length_of_days_with_air_temperature_above_threshold_tr">http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#spell_length_of_days_with_air_temperature_above_threshold_tr</a><br>
           
<a class="moz-txt-link-rfc2396E" href="http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#spell_length_of_days_with_air_temperature_above_threshold_tr"><http://cfconventions.org/Data/cf-standard-names/41/build/cf-standard-name-table.html#spell_length_of_days_with_air_temperature_above_threshold_tr></a><br>
            >>>>>>> Air temperature is the bulk
        temperature of the air, not
        <br>
            the surface (skin) temperature. A spell is the number of
        <br>
            consecutive days on which the condition
        X_below|above_threshold is
        <br>
            satisified. A variable whose standard name has the form
        <br>
            spell_length_of_days_with_X_below|above_threshold *must have
        a
        <br>
            coordinate variable or scalar coordinate variable with the a
        <br>
            standard name of X to supply the threshold*(s).*It must have
        a
        <br>
            climatological time variable, and a cell_method entry* for
        within
        <br>
            days which describes the processing of quantity X before the
        <br>
            threshold is applied. A spell_length_of_days is an intensive
        <br>
            quantity in time, and the cell_methods entry for over days
        can be
        <br>
            any of the methods listed in Appendix E appropriate for
        intensive
        <br>
            quantities e.g. "maximum", "minimum" or "mean".
        <br>
            >>>>>>
        <br>
            >>>>>> And this definition gives a more
        appropriate way to encode
        <br>
            the date of freezing days using a auxiliary coordinate to
        specify
        <br>
            the threshold and use a cell_methods attribute along with
        the
        <br>
            climatology_bounds attribute on time coordinate to specify
        an
        <br>
            statistics over a period.
        <br>
            >>>>>>
        <br>
            >>>>>> The standard_name should be more
        like the definition for
        <br>
            spell_length_of_days, but removing using 'time' as general
        instead
        <br>
            of days. This what I would suggest with respect to the
        encoding:
        <br>
            >>>>>>
        <br>
            >>>>>> variables:
        <br>
            >>>>>>   float first_freeze_date(lat,lon);
        <br>
            >>>>>>
        <br>
           
first_freeze_date:standard_name="time_when_air_temperature_below_threshold";<br>
            >>>>>> 
        first_freeze_date:coordinates="threshold time";
        <br>
            >>>>>>    
        first_freeze_date:cell_methods="time: minimum within
        <br>
            days time: minimum over days";
        <br>
            >>>>>>  first_freeze_date:units="days";
        <br>
            >>>>>>   float last_freeze_date(lat,lon);
        <br>
            >>>>>>
        <br>
           
last_freeze_date:standard_name="time_when_air_temperature_below_threshold";<br>
            >>>>>>
        last_freeze_date:coordinates="threshold time";
        <br>
            >>>>>>
        last_freeze_date:cell_methods="time: minimum within days
        <br>
            time: maximum over days";
        <br>
            >>>>>> last_freeze_date:units="days";
        <br>
            >>>>>>   float threshold;
        <br>
            >>>>>> 
        threshold:standard_name="air_temperature";
        <br>
            >>>>>>     threshold:units="degC";
        <br>
            >>>>>>   double time;
        <br>
            >>>>>> 
        time:climatology="climatology_bounds";
        <br>
            >>>>>>     time:units="days since
        2000-6-1";
        <br>
            >>>>>>   double
        climatology_bounds(time,nv);
        <br>
            >>>>>> data: // time coordinates
        translated to date/time string
        <br>
            type format
        <br>
            >>>>>>   time="2008-01-16T00:00";
        <br>
            >>>>>>  
        climatology_bounds="2007-08-01T00:00", "2008-05-31T00:00";
        <br>
            >>>>>>   threshold=0.;
        <br>
            >>>>>>
        <br>
            >>>>>> The time: minimum over days, on
        first_freeze_date
        <br>
            cell_methods attribute represents the shortest time minimum
        daily
        <br>
            temperature (time: minimum within days) is below threshold.
        <br>
            >>>>>> Equivalent for the
        last_freeze_date, but in this cas
        <br>
            represents the longest time (time: maximum over days).
        <br>
            >>>>>>
        <br>
            >>>>>> Regards
        <br>
            >>>>>>
        <br>
            >>>>>> Antonio
        <br>
            >>>>>>
        <br>
            >>>>>>
        <br>
            >>>>>>
        <br>
            >>>>>>
        <br>
            >>>>>> --
        <br>
            >>>>>> Antonio S. Cofi�o
        <br>
            >>>>>> Associate Professor and Researcher
        <br>
            >>>>>> Grupo de Meteorolog�a de Santander
        <br>
            >>>>>> Dep. of Applied Mathematics and
        Computer Sciences
        <br>
            >>>>>> Universidad de Cantabria (Spain)
        <br>
            >>>>>>
        <br>
            >>>>>> Academic Visitor
        <br>
            >>>>>> National Centre for Atmospheric
        Science
        <br>
            >>>>>> Department of Meteorology
        <br>
            >>>>>> School of Mathematical, Physical
        and Computational Sciences
        <br>
            >>>>>> University of Reading (UK)
        <br>
            >>>>>>
        <br>
            >>>>>> <a class="moz-txt-link-freetext" href="http://antonio.cofino.es">http://antonio.cofino.es</a>
        <br>
            >>>>>> On 15/03/17 18:16, Jim Biard wrote:
        <br>
            >>>>>>>
        <br>
            >>>>>>> Dan,
        <br>
            >>>>>>>
        <br>
            >>>>>>> How about that? I'm working on
        similar products. We
        <br>
            haven't even considered standard names for them.
        <br>
            >>>>>>>
        <br>
            >>>>>>> I went ahead and used 'days
        since YYYY-MM-DD 00:00:00' for
        <br>
            my first and last frost dates, since they are valid dates.
        My
        <br>
            files are structured as (example for first frost date):
        <br>
            >>>>>>>
        <br>
            >>>>>>>     dimensions:
        <br>
            >>>>>>>             time = UNLIMITED ;
        // (56 currently)
        <br>
            >>>>>>>             lon = 960 ;
        <br>
            >>>>>>>             lat = 490 ;
        <br>
            >>>>>>>             bnds = 2 ;
        <br>
            >>>>>>>     variables:
        <br>
            >>>>>>>             double time(time) ;
        <br>
            >>>>>>>  time:standard_name = "time" ;
        <br>
            >>>>>>>  time:long_name = "time" ;
        <br>
            >>>>>>>  time:axis = "T" ;
        <br>
            >>>>>>>  time:units = "days since
        1900-01-01 00:00:00" ;
        <br>
            >>>>>>>  time:calendar = "gregorian" ;
        <br>
            >>>>>>>  time:bounds = "time_bounds" ;
        <br>
            >>>>>>>             double
        time_bounds(time, bnds) ;
        <br>
            >>>>>>>             double lon(lon) ;
        <br>
            >>>>>>>  lon:standard_name =
        "longitude" ;
        <br>
            >>>>>>>  lon:long_name = "longitude" ;
        <br>
            >>>>>>>  lon:units = "degrees_east" ;
        <br>
            >>>>>>>  lon:modulo = 360. ;
        <br>
            >>>>>>>  lon:axis = "X" ;
        <br>
            >>>>>>>  lon:bounds = "lon_bounds" ;
        <br>
            >>>>>>>             double
        lon_bounds(lon, bnds) ;
        <br>
            >>>>>>>             double lat(lat) ;
        <br>
            >>>>>>>  lat:standard_name = "latitude"
        ;
        <br>
            >>>>>>>  lat:long_name = "latitude" ;
        <br>
            >>>>>>>  lat:units = "degrees_north" ;
        <br>
            >>>>>>>  lat:axis = "Y" ;
        <br>
            >>>>>>>  lat:bounds = "lat_bounds" ;
        <br>
            >>>>>>>             double
        lat_bounds(lat, bnds) ;
        <br>
            >>>>>>>             float
        first_freeze_date(time, lat, lon) ;
        <br>
            >>>>>>>  first_freeze_date:_FillValue =
        1.e+20f ;
        <br>
            >>>>>>> 
        first_freeze_date:missing_value = 1.e+20f ;
        <br>
            >>>>>>>  first_freeze_date:comment =
        "Date of the first
        <br>
            >>>>>>>     day with a minimum
        temperature at or below 0 degrees C
        <br>
            over the
        <br>
            >>>>>>>     9 month period starting Aug
        1 of each year." ;
        <br>
            >>>>>>> 
        first_freeze_date:flag_meanings =
        <br>
            >>>>>>>     "No_Freeze_Following" ;
        <br>
            >>>>>>>  first_freeze_date:long_name =
        "First freeze date" ;
        <br>
            >>>>>>>  first_freeze_date:valid_min =
        0. ;
        <br>
            >>>>>>>  first_freeze_date:flag_values
        = -2. ;
        <br>
            >>>>>>>  first_freeze_date:units =
        "days since 1900-01-01
        <br>
            >>>>>>>     00:00:00" ;
        <br>
            >>>>>>>  first_freeze_date:calendar =
        "standard" ;
        <br>
            >>>>>>>
        <br>
            >>>>>>> with the time bounds reflecting
        1 Aug to 1 May for each year.
        <br>
            >>>>>>>
        <br>
            >>>>>>> On 3/15/17 1:50 PM, Hollis, Dan
        wrote:
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> Hi Jon,
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> I�d be interested to know
        how to tackle this problem too.
        <br>
            I�ve recently been generating some datasets of �date of
        first
        <br>
            frost� and �date of last frost� and have no idea how to
        describe
        <br>
            them in a CF-compliant way.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> Jim�s suggestion of
        �day_of_year� is better than just
        <br>
            �days�, however this doesn�t capture what the �something� is
        that
        <br>
            has happened, nor that is the first/last/Nth occurrence of
        that
        <br>
            event. What sort of events are you looking at?
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> In my application I�m just
        looking at UK data, hence my
        <br>
            �year� runs from 1^st July to 30^th June (to span the N
        Hemisphere
        <br>
            winter). It�s easy enough to use the bounds to indicate
        this, but
        <br>
            I�m then not sure what values to store in the data array.
        Number
        <br>
            of days since 1^st July maybe? Or ordinal date (1^st Jan =
        1,
        <br>
            31^st Dec = 365)?
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> Dan
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> PS I have a whole bunch of
        other metrics that I�m looking
        <br>
            at e.g. length of the longest spell, number of spells
        greater then
        <br>
            N days etc. These seem even more complicated to describe
        using CF.
        <br>
            Something for another post I think...
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> *From:*CF-metadata
        <br>
            [<a class="moz-txt-link-freetext" href="mailto:cf-metadata-bounces@cgd.ucar.edu">mailto:cf-metadata-bounces@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata-bounces@cgd.ucar.edu"><mailto:cf-metadata-bounces@cgd.ucar.edu></a>] *On Behalf
        Of *Jim Biard
        <br>
            >>>>>>>> *Sent:* 15 March 2017 16:28
        <br>
            >>>>>>>> *To:*
        <a class="moz-txt-link-abbreviated" href="mailto:cf-metadata@cgd.ucar.edu">cf-metadata@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata@cgd.ucar.edu"><mailto:cf-metadata@cgd.ucar.edu></a>
        <br>
            >>>>>>>> *Subject:* Re:
        [CF-metadata] Recording "day of year on
        <br>
            which something happens"
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> Jon,
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> I agree that a cell_methods
        attribute doesn't seem to be
        <br>
            necessary. A new standard_name like 'day_in_year' or
        'day_of_year'
        <br>
            would likely make things clearer.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> Jim
        <br>
            >>>>>>>>
        <br>
            >>>>>>>> On 3/15/17 11:22 AM, Jon
        Blower wrote:
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     Thanks Jim, that�s very
        helpful. Is cell_methods
        <br>
            necessary in
        <br>
            >>>>>>>>     this case (for the time
        axis bounds) � probably not
        <br>
            since this
        <br>
            >>>>>>>>     isn�t a statistical
        quantity like an average, but a value
        <br>
            >>>>>>>>     that�s �representative�
        of the year.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     I seem to remember from
        a while back that there was a
        <br>
            proposal
        <br>
            >>>>>>>>     to allow time axes to
        use �calendar years since X�
        <br>
            (as opposed
        <br>
            >>>>>>>>     to �years since X�,
        which uses a fixed-length UDUNITS
        <br>
            year),
        <br>
            >>>>>>>>     which might handle this
        use case. I have been out of
        <br>
            the loop
        <br>
            >>>>>>>>     for a while, but I
        can�t find mention of that in the
        <br>
            CF spec,
        <br>
            >>>>>>>>     so maybe that didn�t go
        through.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     I might consider
        requesting a new standard name �
        <br>
            �days� is
        <br>
            >>>>>>>>     good, but I wonder if a
        more specific one would be
        <br>
            helpful.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     Best wishes,
        <br>
            >>>>>>>>     Jon
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     *From: *CF-metadata
        <<a class="moz-txt-link-abbreviated" href="mailto:cf-metadata-bounces@cgd.ucar.edu">cf-metadata-bounces@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata-bounces@cgd.ucar.edu"><mailto:cf-metadata-bounces@cgd.ucar.edu></a>>
        <br>
            >>>>>>>>    
        <<a class="moz-txt-link-freetext" href="mailto:cf-metadata-bounces@cgd.ucar.edu">mailto:cf-metadata-bounces@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata-bounces@cgd.ucar.edu"><mailto:cf-metadata-bounces@cgd.ucar.edu></a>> on
        behalf of Jim
        <br>
            >>>>>>>>     Biard
        <<a class="moz-txt-link-abbreviated" href="mailto:jbiard@cicsnc.org">jbiard@cicsnc.org</a> <a class="moz-txt-link-rfc2396E" href="mailto:jbiard@cicsnc.org"><mailto:jbiard@cicsnc.org></a>>
        <br>
            <<a class="moz-txt-link-freetext" href="mailto:jbiard@cicsnc.org">mailto:jbiard@cicsnc.org</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:jbiard@cicsnc.org"><mailto:jbiard@cicsnc.org></a>>
        <br>
            >>>>>>>>     *Date: *Tuesday, 14
        March 2017 15:12
        <br>
            >>>>>>>>     *To:
        *"<a class="moz-txt-link-abbreviated" href="mailto:cf-metadata@cgd.ucar.edu">cf-metadata@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata@cgd.ucar.edu"><mailto:cf-metadata@cgd.ucar.edu></a>"
        <br>
            >>>>>>>>    
        <<a class="moz-txt-link-freetext" href="mailto:cf-metadata@cgd.ucar.edu">mailto:cf-metadata@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata@cgd.ucar.edu"><mailto:cf-metadata@cgd.ucar.edu></a>>
        <<a class="moz-txt-link-abbreviated" href="mailto:cf-metadata@cgd.ucar.edu">cf-metadata@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata@cgd.ucar.edu"><mailto:cf-metadata@cgd.ucar.edu></a>>
        <br>
            >>>>>>>>    
        <<a class="moz-txt-link-freetext" href="mailto:cf-metadata@cgd.ucar.edu">mailto:cf-metadata@cgd.ucar.edu</a>
        <br>
            <a class="moz-txt-link-rfc2396E" href="mailto:cf-metadata@cgd.ucar.edu"><mailto:cf-metadata@cgd.ucar.edu></a>>
        <br>
            >>>>>>>>     *Subject: *Re:
        [CF-metadata] Recording "day of year
        <br>
            on which
        <br>
            >>>>>>>>     something happens"
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     Jon,
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     1) I'd use 'days'. It
        is a valid standard name apart
        <br>
            from the
        <br>
            >>>>>>>>     'days since date'
        formalism. It's not perfect, but
        <br>
            it's legal.
        <br>
            >>>>>>>>     You could,
        alternatively, request a new standard name.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     2) Use a time_bounds
        variable. I would tend to set
        <br>
            the time to
        <br>
            >>>>>>>>     be July 1 at midnight
        for each year, and set the
        <br>
            bounds for
        <br>
            >>>>>>>>     each year to Jan 1 of
        that year and Jan 1 of the next
        <br>
            year.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     Grace and peace,
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     Jim
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>     On 3/14/17 10:43 AM,
        Jon Blower wrote:
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         Hi all,
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         We need to
        structure a NetCDF file that will hold
        <br>
            a variable that represents the day of the year on which an
        event
        <br>
            happened (integers from 0 to 366). This value is recorded
        every
        <br>
            year for a number of years. I have a couple of questions
        about how
        <br>
            best to do this:
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         1. What is the best
        standard name to use for the
        <br>
            day of the year? I didn�t find anything in the standard name
        <br>
            table, although I might have missed it.
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         2. What would be
        the best way to define the time
        <br>
            axis? Each point along the axis would represent a whole
        year,
        <br>
            rather than an instant in time. I could simply pick an
        arbitrary
        <br>
            instant (e.g. midnight on 1st Jan) to represent the year,
        but is
        <br>
            there a better way?
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         Thanks in advance
        for any help!
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>         Jon
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>>>>>
        <br>
            >>>>
        <br>
            >>>>
        <br>
            >>>
        <br>
            >>>
        <br>
            >>>
        <br>
            >>> _______________________________________________
        <br>
            >>> CF-metadata mailing list
        <br>
            >>>
        <br>
            >>> <a class="moz-txt-link-abbreviated" href="mailto:CF-metadata@cgd.ucar.edu">CF-metadata@cgd.ucar.edu</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:CF-metadata@cgd.ucar.edu"><mailto:CF-metadata@cgd.ucar.edu></a>
        <br>
            >>>
        <a class="moz-txt-link-freetext" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata">http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata</a>
        <br>
           
        <a class="moz-txt-link-rfc2396E" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata"><http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata></a>
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            >> --
        <br>
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        <br>
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        <br>
            >> NOAA National Centers for Environmental Information
        <br>
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        <br>
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        <br>
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        <a class="moz-txt-link-rfc2396E" href="mailto:jbiard@cicsnc.org"><mailto:jbiard@cicsnc.org></a>
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            >>
        <br>
            >> _______________________________________________
        <br>
            >> CF-metadata mailing list
        <br>
            >>
        <br>
            >> <a class="moz-txt-link-abbreviated" href="mailto:CF-metadata@cgd.ucar.edu">CF-metadata@cgd.ucar.edu</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:CF-metadata@cgd.ucar.edu"><mailto:CF-metadata@cgd.ucar.edu></a>
        <br>
            >>
        <a class="moz-txt-link-freetext" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata">http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata</a>
        <br>
           
        <a class="moz-txt-link-rfc2396E" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata"><http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata></a>
        <br>
            >
        <br>
            > --
        <br>
            > John Helly, University of California, San Diego / San
        Diego
        <br>
            Supercomputer Center / Scripps Institution of Oceanography /
        760
        <br>
            840 8660 mobile /
        <br>
            > <a class="moz-txt-link-freetext" href="http://www.sdsc.edu/~hellyj">http://www.sdsc.edu/~hellyj</a>
        <a class="moz-txt-link-rfc2396E" href="http://www.sdsc.edu/%7Ehellyj"><http://www.sdsc.edu/%7Ehellyj></a>
        <br>
            >
        <br>
            > ORCID ID: orcid.org/0000-0002-3779-0603
        <br>
            <a class="moz-txt-link-rfc2396E" href="http://orcid.org/0000-0002-3779-0603"><http://orcid.org/0000-0002-3779-0603></a>
        <br>
            >
        <br>
            >
        <hellyj.vcf>_______________________________________________
        <br>
            > CF-metadata mailing list
        <br>
            > <a class="moz-txt-link-abbreviated" href="mailto:CF-metadata@cgd.ucar.edu">CF-metadata@cgd.ucar.edu</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:CF-metadata@cgd.ucar.edu"><mailto:CF-metadata@cgd.ucar.edu></a>
        <br>
            >
        <a class="moz-txt-link-freetext" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata">http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata</a>
        <br>
           
        <a class="moz-txt-link-rfc2396E" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata"><http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata></a>
        <br>
        <br>
            **********************
        <br>
            "The contents of this message do not reflect any position of
        the
        <br>
            U.S. Government or NOAA."
        <br>
            **********************
        <br>
            Roy Mendelssohn
        <br>
            Supervisory Operations Research Analyst
        <br>
            NOAA/NMFS
        <br>
            Environmental Research Division
        <br>
            Southwest Fisheries Science Center
        <br>
            ***Note new street address***
        <br>
            110 McAllister Way
        <br>
            Santa Cruz, CA 95060
        <br>
            Phone: (831)-420-3666
        <br>
            Fax: (831) 420-3980
        <br>
            e-mail: <a class="moz-txt-link-abbreviated" href="mailto:Roy.Mendelssohn@noaa.gov">Roy.Mendelssohn@noaa.gov</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:Roy.Mendelssohn@noaa.gov"><mailto:Roy.Mendelssohn@noaa.gov></a>
        <br>
            www: <a class="moz-txt-link-freetext" href="http://www.pfeg.noaa.gov/">http://www.pfeg.noaa.gov/</a>
        <br>
        <br>
            "Old age and treachery will overcome youth and skill."
        <br>
            "From those who have been given much, much will be expected"
        <br>
            "the arc of the moral universe is long, but it bends toward
        <br>
            justice" -MLK Jr.
        <br>
        <br>
            _______________________________________________
        <br>
            CF-metadata mailing list
        <br>
            <a class="moz-txt-link-abbreviated" href="mailto:CF-metadata@cgd.ucar.edu">CF-metadata@cgd.ucar.edu</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:CF-metadata@cgd.ucar.edu"><mailto:CF-metadata@cgd.ucar.edu></a>
        <br>
            <a class="moz-txt-link-freetext" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata">http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata</a>
        <br>
           
        <a class="moz-txt-link-rfc2396E" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata"><http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata></a>
        <br>
        <br>
        <br>
        <br>
        <br>
        _______________________________________________
        <br>
        CF-metadata mailing list
        <br>
        <a class="moz-txt-link-abbreviated" href="mailto:CF-metadata@cgd.ucar.edu">CF-metadata@cgd.ucar.edu</a>
        <br>
        <a class="moz-txt-link-freetext" href="http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata">http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata</a>
        <br>
      </blockquote>
      <br>
      <br>
    </blockquote>
    <br>
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                        <span style="font-size: 11px; "><span
                            style="font-family: arial, helvetica,
                            sans-serif; ">
                            <b>Jim Biard</b>
                            <br>
                            <b>Research Scholar</b>
                            <br>
                            <a href="http://cicsnc.org/" style="color:
                              rgb(38, 58, 143); text-decoration: none;
                              font-weight: bold; ">
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                              Satellites NC
                            </a>
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                            <a href="http://ncsu.edu/" style="color:
                              rgb(38, 58, 143); text-decoration: none;
                              font-weight: bold; ">
                              North Carolina State University
                            </a>
                            <br>
                            <a href="http://ncdc.noaa.gov/"
                              style="color: rgb(38, 58, 143);
                              text-decoration: none; font-weight: bold;
                              ">
                              NOAA National Centers for Environmental
                              Information
                            </a>
                            <br>
                            <i>formerly NOAA’s National Climatic Data
                              Center</i>
                            <br>
                            151 Patton Ave, Asheville, NC 28801
                            <br>
                            e: <a href="mailto:jbiard@cicsnc.org"
                              style="color: rgb(38, 58, 143); ">jbiard@cicsnc.org</a>
                            <br>
                            o: +1 828 271 4900
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