[Seavox] FW: L06 extensions

Nan Galbraith ngalbraith at whoi.edu
Mon Aug 12 15:45:01 BST 2013


Hi Roy -

That's good. The trajectory's dimensions can't necessarily be inferred from
the instrument for sub-surface gliders, but can be for surface gliders, 
is that
going to be a problem?

*27- sub-surface gliders- platform with buoyancy-based propulsion that
**is capable of operation at depths significantly below the surface*
*3C- surface gliders- platform with buoyancy-based propulsion that 
**operates
        at a single depth near the sea surface*

- Nan

On 8/12/13 10:14 AM, Lowry, Roy K. wrote:
> Hi Nan,
> Is the way of getting around this to phrase it along the lines of 'is 
> capable of operation at depths significantly below the surface'?
> Cheers, Roy.
> ------------------------------------------------------------------------
> *From:* seavox-bounces at mailman.nerc-liv.ac.uk 
> [seavox-bounces at mailman.nerc-liv.ac.uk] On Behalf Of Nan Galbraith 
> [ngalbraith at whoi.edu]
> *Sent:* 12 August 2013 14:52
> *To:* seavox at mailman.nerc-liv.ac.uk
> *Subject:* Re: [Seavox] FW: L06 extensions
>
> Hi Roy and John -
>
> One comment on 27 -  aren't there subsurface gliders that operate at 
> one depth - or
> that are sometimes operated at one depth?  And, since they are also 
> free to surface,
> occasionally, could you use 'at variable depths' instead of'at 
> variable depths significantly
> below the surface' '?
>
> And for 3c, instead of 'that is confined to operation on the sea 
> surface' could you use
> 'that operates at a single depth near the sea surface'?
>
> I found it easier if I put the additions in context with related L06 
> terms, below, because
> then  I could see how these fit into the vocabulary.
>
> 25- autonomous underwater vehicle- free-roving platform operating in 
> the water column with
>     propulsion  but no human operator on board (e.g. Autosub, Glider).
> *27- sub-surface gliders- platform with buoyancy-based propulsion that 
> is able to
>     operate within the water column. *
> 3B- autonomous surface water vehicle- self-propelled vehicle operating 
> on the sea
> surface with no human occupants.
> *3C- surface gliders- platform with buoyancy-based propulsion that is 
> confined
>     to operation on the sea surface. *
> 42- drifting surface float- unmanned instrumented platform operating 
> on the
>     surface of the water column often attached to a drogue to track 
> currents
>     rather than winds (e.g. Argos buoy).
> 44- drifting subsurface float- unmanned instrumented platform drifting 
> freely
>     in the water column at a depth governed by its density (e.g. 
> Swallow float)
> 46- drifting subsurface profiling float- unmanned instrumented 
> platform drifting
>     freely in the water column that periodically makes vertical traverses
>     through the water column (e.g. Argo float)
> 47- float- free-floating platform either on the surface of the water 
> column
>     or at a predetermined depth within the water column.
>
>
> Cheers - Nan
>
>
>
>
>
>
> On 8/12/13 3:30 AM, Lowry, Roy K. wrote:
>> Should have replied to the list, not just John....
>> ------------------------------------------------------------------------
>> *From:* Lowry, Roy K.
>> *Sent:* 12 August 2013 08:19
>> *To:* John Graybeal
>> *Subject:* RE: [Seavox] L06 extensions
>>
>> Hi John,
>> I think we're on different wavelengths regarding the gliders.  What 
>> I'm trying to distinguish - following your initial suggestion - are 
>> gliders whose spatio-temporal feature type may be reasonably 
>> be considered a 2D trajectory (i.e. having a single nominal depth in 
>> metadata works) from those where the feature type needs to be a 3D 
>> trajectory (i.e. the data make no sense without a depth co-ordinate 
>> variable).  You obviously didn't get this from my definitions. The 
>> need to surface didn't come into it. If I replace 'within the water 
>> column' by 'at variable depths significantly below the surface' does 
>> that make it clearer?
>> A drogue is an underwater parachute attached at a depth of around 40m 
>> to surface drifting buoys to encourage them to follow the motion of 
>> the water rather than the surface winds.  I considered this to be a 
>> well-known term - it's certainly well used by people I know. 
>> Admittedly 'undrogued' is an adaptation of the word that won't be 
>> found in the Oxford English Dictionary, but it is creeping into 
>> common usage in the operational oceanography community. According 
>> to JCOMMOPS it is critical to the definition.  I'll clarify by adding 
>> '(no underwater parachute)' unless anybody else objects.
>> I inherited the sea ice definitions (via Mathieu at JCOMMOPS) from 
>> The Canadian Ice Service of Environment Canada, but rephrased them 
>> slightly - possibly not very well. Can anybody provide me with 
>> improved wording?
>> Cheers, Roy.
>> ------------------------------------------------------------------------
>> *From:* seavox-bounces at mailman.nerc-liv.ac.uk 
>> [seavox-bounces at mailman.nerc-liv.ac.uk] On Behalf Of John Graybeal 
>> [jbgraybeal at mindspring.com]
>> *Sent:* 09 August 2013 16:59
>> *To:* seavox at mailman.nerc-liv.ac.uk
>> *Subject:* Re: [Seavox] L06 extensions
>>
>> A few thoughts.
>>
>> 3C and 27 are difficult to distinguish. No gliders are exclusively on 
>> the sea surface, if by 'glider' we mean a system that uses buoyancy 
>> to initiate forward motion. They are all able to operate within the 
>> water column.  So I might say
>> 3C: A platform with buoyancy-based propulsion that routinely surfaces 
>> to meet its objectives.
>> 27: A platform with buoyancy-based propulsion that can routinely meet 
>> its mission objectives without surfacing.
>> These are then mutually exclusive.
>>
>> 49: The term 'undrogued' is unfamiliar to me, and to my 3 buddies 
>> with ocean background. Looking it up seems to product multiple 
>> definitions. Any chance we could be more specific? Or perhaps it 
>> isn't critical to the definition?
>>
>> 93/94: 'covering over/under 70% of the sea surface' -- at what scale 
>> is this metric assessed? I assume we don't mean of the _entire_ sea 
>> surface, but we don't mean of the sea surface within 1 meter, either.
>>
>> John
>>
>>
>>
>>
>>
>> On Aug 1, 2013, at 05:49, "Lowry, Roy K." <rkl at bodc.ac.uk 
>> <mailto:rkl at bodc.ac.uk>> wrote:
>>
>>> Dear All,
>>> Discussions on this have gone quiet, so I'll summarise what has been 
>>> said into a proposal for change:
>>> New codes:
>>> CODE: 3C
>>> Preferred Label: surface gliders
>>> Definition: A platform with buoyancy-based propulsion that is 
>>> confined to operation on the sea surface.
>>> Mapping: broadMatch to surface autonomous vehicle
>>> CODE: 27
>>> Preferred Label: sub-surface gliders
>>> Definition: A platform with buoyancy-based propulsion that is able 
>>> to operate within the water column.
>>> Mapping: broadMatch to autonomous underwater vehicle
>>> CODE: 49
>>> Preferred Label:  surface ice buoy
>>> Definition: An undrogued surface float that is deployed in regions 
>>> where sea ice forms that moves with either ice or water depending 
>>> upon the time of year.
>>> Mapping: broadMatch drifting surface float
>>> CODE: 93
>>> Preferred Label: pack ice
>>> Definition: Sea ice not connected to land covering over 70% of the 
>>> sea surface.
>>> Mapping: broadMatch cryosphere
>>> CODE: 94
>>> Preferred Label: drift ice
>>> Definition: Sea ice not connected to land covering under 70% of the 
>>> sea surface.
>>> Mapping: broadMatch cryosphere
>>> If there are no further comments I'll add these records to the 
>>> vocabulary when I return from leave on August 20^th .
>>> Cheers, Roy.
>>>

-- 
*******************************************************
* Nan Galbraith        Information Systems Specialist *
* Upper Ocean Processes Group            Mail Stop 29 *
* Woods Hole Oceanographic Institution                *
* Woods Hole, MA 02543                 (508) 289-2444 *
*******************************************************


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.nerc-liv.ac.uk/pipermail/seavox/attachments/20130812/596e15d7/attachment.html 


More information about the Seavox mailing list