Dear John, Jonathan and Karl,
thank you for your feedback.
x_wind_[speed_]of_gust
I like best x_wind_of_gust, since x_wind is a vector-component of a
velocity, so it is not a pure speed, and neither a pure direction. I
think it should be as close to x_wind as possible - though I see the
point of eventually changing x_wind in the future.
In AROME, wind-gusts are parametrized in a different way than a pure
statistical extraction, so cell_method: time: max would be wrong here.
graupel_fall_amount
That is fine with us.
inland_water_area_fraction
I like the definition of wikipedia for sea:
"The sea is the connected body of salty water that covers over 70
percent of the Earth's surface."
The border between 'river-delta' and the sea might be very difficult to
define, though. It might be an idea to add this definition to
sea_area_fraction.
We use the area_fraction + type for soil-types. Since we use already
sea_area_fraction and land_area_fraction, inland_water_area_fraction
feels like a logical continuation of the division in land and water.
Best regards,
Heiko
On 2014-05-22 20:03, John Graybeal wrote:
> Karl,
>
> I've wondered about this 'gust' question myself, with respect to
> wind_speed_of_gust, and to many other names with statistical components
> (mean, st_dev, minimum, etc.). I've always assumed that this either
> reflected (a) convenience, or (b) the reality that many sensors return
> data that is already parameterized (?), and so the characteristics
> required for cell methods might not be readily captured.
>
> I would appreciate hearing further clarification of the CF principles in
> these cases. (Can be added to the FAQ!)
>
> John
>
>
> On May 22, 2014, at 09:48, Karl Taylor <taylor13 at llnl.gov
> <mailto:taylor13 at llnl.gov>> wrote:
>>
>> Hi Heiko et al.,
>>
>> I agree that if we include the "gust" name, it should include "speed"
>> as in x_wind_speed_of_gust (for consistency with previous name).
>>
>> Alternatively, I'm not sure wind_speed_of _gust should ever be used
>> when referring to observations or in many models, since it's just the
>> maximum wind speed occurring during an interval, and it's not a
>> different quantity from wind speed itself. If the
>> x_wind_speed_of_gust is some parameterized quantity and can't be
>> obtained from the x_wind time series (sampled at model time-step),
>> then there might be an argument for defining a new standard_name.
>>
>> best regards,
>> Karl
>>
>>
>> On 5/22/14, 9:27 AM, John Graybeal wrote:
>>> Hello Heiko, thanks for the requests.
>>>
>>> Re x|y_wind_gust, for consistency with existing names would x_wind_speed_of_gust and y_wind_speed_of_gust be OK, for consistency with the existing name wind_speed_of_gust?
>>>
>>> The description of graupel should be included in this definition. For example "Graupel is precipitation that forms when supercooled droplets of water are collected and freeze on a falling snowflake, forming a 2?5 mm (0.079?0.197 in) ball of rime." Stolen from wikipedia, you may have better/preferred language.
>>>
>>> Re the name graupelfall_amount, my web search found only uses that treat graupel as a separate word (except in German), so is graupel_fall_amount acceptable? I know it doesn't match the existing snowfall/rainfall etc., but those are common English words.
>>>
>>> For inland_water_area_fraction, I don't know how to interpret 'inland water ... is all water-surfaces which are not "sea" '. Are bays, fjords, etc. inland water? Is there a clear transition at the river delta of which part is inland and which is not? For CF this may not be essential, but if the answers are well known it would be helpful to state them. (And if not, maybe just say something like 'inland water does not include any ocean or sea'.)
>>>
>>> John
>>>
>>> On May 22, 2014, at 01:10, Heiko Klein<Heiko.Klein at met.no> wrote:
>>>
>>>> Hi,
>>>>
>>>> we're currently converting the AROME model output to netcdf and have problems finding good standard_names for some of the parameters. Therefore, we would like to request the following new standard_names:
>>>>
>>>> x_wind_gust:
>>>> definition: "x" indicates a vector component along the grid x-axis, positive with increasing x. Wind is defined as a two-dimensional (horizontal) air velocity vector, with no vertical component. (Vertical motion in the atmosphere has the standard name upward_air_velocity.)
>>>> A gust is a sudden brief period of high wind speed. In an observed timeseries of wind speed, the gust wind speed can be indicated by a cell_methods of maximum for the time-interval. In an atmospheric model which has a parametrised calculation of gustiness, the gust wind speed may be separately diagnosed from the wind speed.
>>>> units: m/s
>>>>
>>>> y_wind_gust:
>>>> (see x_wind_gust. The definition is taken from the existing x_wind and wind_speed_of_gust)
>>>>
>>>>
>>>>
>>>> graupelfall_amount:
>>>> definition: "Amount" means mass per unit area.
>>>> units: kg m-2
>>>>
>>>>
>>>> inland_water_area_fraction:
>>>> definition: "X_area_fraction" means the fraction of horizontal area occupied by X. "X_area" means the horizontal area occupied by X within the grid cell. "inland_water" is water surrounded by land-masses like rivers and lakes, and is all water-surfaces which are not "sea".
>>>>
>>>>
>>>> Best regards,
>>>>
>>>> Heiko
>>>> (on behalf of the MET Norway Arome team)
>>>>
>>>>
>>>>
>>>> --
>>>> Dr. Heiko Klein Tel. + 47 22 96 32 58
>>>> Development Section / IT Department Fax. + 47 22 69 63 55
>>>> Norwegian Meteorological Institutehttp://www.met.no
>>>> P.O. Box 43 Blindern 0313 Oslo NORWAY
>>>> _______________________________________________
>>>> CF-metadata mailing list
>>>> CF-metadata at cgd.ucar.edu
>>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>> ------------------------------------
>>> John Graybeal
>>> Marine Data Manager
>>>
>>> M +1 408 675-5445
>>> skype: graybealski
>>> Marinexplore
>>> 920 Stewart Drive
>>> Sunnyvale 94085
>>> California, USA
>>> www.marinexplore.com
>>>
>>> _______________________________________________
>>> CF-metadata mailing list
>>> CF-metadata at cgd.ucar.edu
>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>
>>
>>
>> _______________________________________________
>> CF-metadata mailing list
>> CF-metadata at cgd.ucar.edu <mailto:CF-metadata at cgd.ucar.edu>
>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>
> ------------------------------------
> *John Graybeal*
> Marine Data Manager
>
> M +1 408 675-5445
> skype: graybealski
> Marinexplore
> 920 Stewart Drive
> Sunnyvale 94085
> California, USA
> www.marinexplore.com <http://marinexplore.com>
>
>
>
> _______________________________________________
> CF-metadata mailing list
> CF-metadata at cgd.ucar.edu
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>
--
Dr. Heiko Klein Tel. + 47 22 96 32 58
Development Section / IT Department Fax. + 47 22 69 63 55
Norwegian Meteorological Institute http://www.met.no
P.O. Box 43 Blindern 0313 Oslo NORWAY
Received on Fri May 23 2014 - 03:15:08 BST
