Dear Jim
> If that's the general consensus, then we can go that general
> direction. I'll prepare pairs of everything.
Thank you for your flexibility.
> Regarding Nan's suggestions for names - I'm not a "ship person" so
> starboard and port are unfamiliar terms that I have to constantly
> check myself on. I dislike putting them in the names. I don't see
> them in regular use in the satellite domain. The same goes for bow
> as far as usage outside of the ship domain. Airplanes have noses.
> Satellites have ... I don't know if there is even a name, as there
> is no need for a leading edge. I'll struggle to find something, and
> then we can wrangle over it.
I agree with you - it would be better to have something generic and self-
explanatory, even if it diverges from familiar terminology.
> I think the "most intuitive" way to represent the angles - and most
> consistent as well, in my view - is clockwise rotations around the
> unit vectors. This makes positive yaw to starboard, positive pitch
> nose up, and positive roll starboard up. But we are talking about
> having both signs represented in names, so I guess that is moot.
I agree with this too. For describing polygonal bounds, we say that the
vertices should be traversed anticlockwise as seen from above. That is a
positive direction of rotation around the vertical axis, since longitude-
latitude-upward is a right-handed coordinate system. I suppose this is the
yaw rotation - but is that the opposite sign from yours?
Best wishes
Jonathan
>
> On 9/3/18 12:51 PM, Jonathan Gregory wrote:
> >Dear Roy and Nan
> >
> >I agree that if there are existing names whose sign convention is undefined
> >we can't retrospectively define it. I think those ones ought to be deprecated,
> >though, in favour of new ones with signs indicated.
> >
> >Best wishes
> >
> >Jonathan
> >
> >----- Forwarded message from Nan Galbraith <ngalbraith at whoi.edu> -----
> >
> >>Date: Sun, 02 Sep 2018 11:57:33 -0400
> >>From: Nan Galbraith <ngalbraith at whoi.edu>
> >>To: "Lowry, Roy K." <rkl at bodc.ac.uk>
> >>Cc: cf-metadata at cgd.ucar.edu
> >>Subject: Re: [CF-metadata] Platform Heave
> >>User-Agent: Internet Messaging Program (IMP) H4 (5.0.23)
> >>
> >>I second Roy's suggestion; existing names have undefined directionality,
> >>and new names have explicit directions. This seems like the only way to
> >>move forward. If there's a difference of opinion on which direction
> >>should be in the new name, we can easily create a pair for each term.
> >>
> >>What would the explicit names be? Some of the terms in the thread
> >>below use 'right' and 'left' where 'port' and 'starboard' might be
> >>more clear, since, as Roy points out, left and right can be taken
> >>as 'looking forwards from the platform or looking at the front of
> >>the platform.'
> >>
> >>I also agree that these are the most intuitive way to represent these
> >>angles/motions:
> >>>heave positive up
> >>>pitch positive bow up
> >>>yaw positive to starboard roll positive starboard side down
> >>Would the names be something like heave_up, pitch_bow_up, yaw_to_starboard,
> >>and roll_to_starboard? We do need to differentiate these from the exiting
> >>names.
> >>
> >>Regards - Nan
> >>
> >>Quoting "Lowry, Roy K." <rkl at bodc.ac.uk>:
> >>
> >>>Dear Jim,
> >>>
> >>>
> >>>>From my researches into existing oceanographic data sets
> >>>>(SeaDataCloud holdings plus EU glider data projects), covering
> >>>>heave, pitch, roll and yaw. I haven't discovered a single
> >>>>deviation from the conventions:
> >>>
> >>>heave positive up
> >>>
> >>>Pitch positive bow/nose up
> >>>
> >>>yaw positive to starboard
> >>>
> >>>roll starboard side down
> >>>
> >>>
> >>>I have yet to find any data sets, other than those described by
> >>>Ken in these discussions, in my searches containing surge or sway.
> >>>
> >>>
> >>>The only ambiguity I have found in the wider domain of Google is
> >>>where the concept of 'positive clockwise' has been used without
> >>>specifying whether the observer is looking forwards from the
> >>>platform or looking at the front of the platform. This isn't
> >>>helped by the multitude of bidirectional vectors (arrows at each
> >>>end) in illustrative diagrams.
> >>>
> >>>
> >>>Might our lives be made easier if we adopted a set of conventions,
> >>>state them explicitly in the Standard Names as Jonathan suggests
> >>>leaving room in the unlikely - in my view at least - event of
> >>>Standard Names for the opposite convention being required?
> >>>
> >>>
> >>>Cheers, Roy.
> >>>
> >>>
> >>>I have now retired but will continue to be active through an
> >>>Emeritus Fellowship using this e-mail address.
> >>>
> >>>
> >>>________________________________
> >>>From: CF-metadata <cf-metadata-bounces at cgd.ucar.edu> on behalf of
> >>>Jim Biard <jbiard at cicsnc.org>
> >>>Sent: 31 August 2018 14:38
> >>>To: cf-metadata at cgd.ucar.edu
> >>>Subject: Re: [CF-metadata] Platform Heave
> >>>
> >>>
> >>>Jonathan,
> >>>
> >>>That's only part of the issue. Here are the issues as I see them.
> >>>
> >>> * There is no single sign convention being followed in
> >>>existing datasets "in the wild".
> >>> * There is a long-standing convention for vertical coordinates
> >>>using the attribute positive rather than having pairs of standard
> >>>names for height_positive_up, height_positive_down, etc. The
> >>>suggested solution is corollary, and the positive attribute could
> >>>be used instead of adding a new attribute named direction with a
> >>>suitable expansion of possible valid values.
> >>> * In order to cover all bases, we'd need three versions for
> >>>each standard name (e.g. - platform_roll, platform_roll_clockwise,
> >>>platform_roll_anticlockwise - or similar names)
> >>> * Having three different versions of each standard name will
> >>>lead to new possibilities for getting things wrong by picking the
> >>>wrong version.
> >>> * Semantically, there is only one concept in each case. If I
> >>>am searching for roll variables and I have multiple names that
> >>>mean roll, I must expand my search to include all variants. This
> >>>is a small example, but there are other examples of this problem
> >>>that are definitely not trivial and defeat one of the goals for
> >>>using standard names - being able to find like quantities across
> >>>datasets, particularly using automated techniques rather than
> >>>human eyes.
> >>>
> >>>Grace and peace,
> >>>
> >>>Jim
> >>>
> >>>On 8/31/18 8:52 AM, Jonathan Gregory wrote:
> >>>
> >>>Dear all
> >>>
> >>>I haven't been following this discussion, so please excuse me if I've missed
> >>>the point. I think you are suggesting introducing a new attribute to indicate
> >>>the positive sense of various new quantities for platform orientation - is
> >>>that right? To do that would not be consistent with other standard
> >>>names, which
> >>>(where relevant) all have the positive sense indicate in the standard name
> >>>itself. That's why there are many pairs of standard names for
> >>>upward/downward,
> >>>in particular. The reason for doing this is to make it impossible to name the
> >>>quantity without indicating its sign convention, whereas a separate attribute
> >>>can be omitted, and probably sometimes will. It also opens new possibilities
> >>>for getting things wrong, by putting illegal values in it.
> >>>
> >>>Therefore I would argue for the same approach here, both because I think it's
> >>>less error-prone, and for consistency with other CF standard names. I'm sure
> >>>the objection occurs to you that this means more standard names. That's true,
> >>>but it's only twice as many, I believe, since each of the quantities has only
> >>>two possible senses.
> >>>
> >>>Best wishes
> >>>
> >>>Jonathan
> >>>
> >>>----- Forwarded message from Kenneth Kehoe
> >>><kkehoe at ou.edu><mailto:kkehoe at ou.edu> -----
> >>>
> >>>
> >>>
> >>>Date: Thu, 30 Aug 2018 12:05:44 -0600
> >>>From: Kenneth Kehoe <kkehoe at ou.edu><mailto:kkehoe at ou.edu>
> >>>To: cf-metadata at cgd.ucar.edu<mailto:cf-metadata at cgd.ucar.edu>
> >>>Subject: Re: [CF-metadata] Platform Heave
> >>>User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:60.0)
> >>> Gecko/20100101 Thunderbird/60.0
> >>>
> >>>I think we should keep things simple as Ethan suggests below. But
> >>>since the proposed attribute "direction" is defined as indicating
> >>>the positive direction we don't need to include the word positive.
> >>>
> >>>The terms would then be:
> >>>roll: "right_side_up" and "right_side_down"
> >>>pitch: "nose_up" and "nose_down"
> >>>yaw: "nose_right" and "nose_left"
> >>>surge: "forward" and "backward"
> >>>sway: "left" and "right"
> >>>heave: "up" and "down"
> >>>
> >>>It would be nice to be more explicit in the netCDF file and require
> >>>less on the standard_name definition so I would suggest we use the
> >>>original proposed attribute name of "positive_direction" with the
> >>>above allowed values.
> >>>
> >>>Or if we don't want to add a new attribute we could use the existing
> >>>"positive" attribute and expand its allowed use. I've proposed this
> >>>in the past and it was decided to not expand the definition. I think
> >>>the concern for not expanding positive was the requirement of only
> >>>using that attribute on coordinate variables. For the coordinate
> >>>variable the only allowable values are up and down. But for this use
> >>>those values would only be attached to a variable, not a coordinate
> >>>variable.
> >>>
> >>>Since we are creating an attribute to define the positive direction
> >>>I would like to add radial definition of "toward" and "away". But I
> >>>think we can simplify this a bit further. If we define the point of
> >>>reference that is moving in the standard name then we don't need to
> >>>put the point of reference in the positive (or direction or
> >>>positive_direction) attribute. For example the pitch standard_name
> >>>would indicate the location of reference of the nose. This would
> >>>then reduce the list of possible options to:
> >>>
> >>>roll: "up" and "down"
> >>>pitch: "up" and "down"
> >>>yaw: "right" and "left"
> >>>surge: "forward" and "backward"
> >>>sway: "left" and "right"
> >>>heave: "up" and "down"
> >>>
> >>>If we could use the current attribute of "positive" that has up and
> >>>down already defined then we only need to to add "right", "left",
> >>>"forward", "backward", "toward", "away".
> >>>
> >>>Easy!
> >>>
> >>>
> >>>Ken
> >>>
> >>>
> >>>
> >>>On 2018-8-29 13:54, Ethan Davis wrote:
> >>>
> >>>
> >>>Hey Jim,
> >>>
> >>>How about removing one layer of terminology by using your
> >>>definitions for the allowed values of "direction":
> >>>
> >>>roll: "positive_right_side_up" and "positive_right_side_down".
> >>>pitch: "positive_nose_up" and "positive_nose_down".
> >>>yaw: "positive_nose_right" and "positive_nose_left".
> >>>surge: "positive_forward" and "positive_backward".
> >>>sway: "positive_left" and "positive_right".
> >>>heave: "positive_up" and "positive_down".
> >>>
> >>>Cheers,
> >>>
> >>>Ethan
> >>>
> >>>On Wed, Aug 29, 2018 at 12:02 PM Jim Biard
> >>><jbiard at cicsnc.org<mailto:jbiard at cicsnc.org>
> >>><mailto:jbiard at cicsnc.org><mailto:jbiard at cicsnc.org>> wrote:
> >>>
> >>> John,
> >>>
> >>> There are a variety of conventions for defining roll, pitch, and
> >>> yaw out there. This is why we are avoiding a specific one. Others
> >>> have searched existing datasets that are using earlier versions of
> >>> these standard names (or not using standard names) and found that
> >>> they don't all follow the same convention.
> >>>
> >>> Ethan,
> >>>
> >>> We purposely aren't answering that question directly because of
> >>> the issue above. I believe that I have consistently followed the
> >>> convention in which clockwise and anticlockwise are rotational
> >>> directions around a unit vector facing the observer, where the X
> >>> unit vector is in the nominally forward direction, the Z axis is
> >>> in the local up direction, and the Y axis unit vector is "Z cross
> >>> X", which forms a right-handed coordinate system. The terms are
> >>> meaningful and accurate using that convention, but the names could
> >>> be "alpha" and "beta" or "dog" and "cat" as long as they are used
> >>> correctly.
> >>>
> >>> This whole topic is fraught with competing conventions, so we are
> >>> attempting to avoid declaring that only one of them is valid, with
> >>> it's corresponding requirement that everyone follow that one sign
> >>> convention.
> >>>
> >>> In fact, we could reword things to remove naming the axes X, Y,
> >>> and Z, and perhaps we should. I know of satellite platforms that
> >>> define their Y axis unit vector as pointing forward and the Z axis
> >>> unit vector as pointing down.
> >>>
> >>> Thoughts?
> >>>
> >>> Grace and peace,
> >>>
> >>> Jim
> >>>
> >>>
> >>> On 8/29/18 1:32 PM, John Helly wrote:
> >>>
> >>>
> >>> Perhaps one should refer to the discipline of hydrostatics for
> >>> help with this? This paper, pulled from a quick search, has a
> >>> diagram referencing the platforms' frame of reference with
> >>> respect to its center of gravity. Sorry if this comment is
> >>> retrograde.
> >>>
> >>> https://www.hindawi.com/journals/mpe/2010/934714/
> >>><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.hindawi.com_journals_mpe_2010_934714_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=NV5FW-iZ7Ml9G3tz6Dg4tXjiM7w1mDsctSx_tWbiTmc&e=><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.hindawi.com_journals_mpe_2010_934714_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=NV5FW-iZ7Ml9G3tz6Dg4tXjiM7w1mDsctSx_tWbiTmc&e=>
> >>>
> >>> J.
> >>>
> >>> On 8/29/18 10:09, Ethan Davis wrote:
> >>>
> >>>
> >>> Hi Jim, all,
> >>>
> >>> I'm a bit confused by the "clockwise" and "anticlockwise". You
> >>> mention the orientation of the observer but not the
> >>> location/orientation of the clock. My assumptions (not sure why)
> >>> for the clock: for roll, the observer (who is facing forward)
> >>> would be facing the clock; for pitch, the observer would look
> >>> right to see the clock; and for yaw, the observer would look
> >>> down to see the clock. That works for your definitions of pitch
> >>> and yaw, but is backwards for roll.
> >>>
> >>> Does "clockwise" add, in some way, another degree of freedom to
> >>> the definition? Does that degree of freedom need to be nailed
> >>> down in the definitions? Or other terms used instead? I don't
> >>> have any good suggestions other than "positive" and "negative".
> >>>
> >>> Cheers,
> >>>
> >>> Ethan
> >>>
> >>> On Wed, Aug 29, 2018 at 9:03 AM Jim Biard
> >>><jbiard at cicsnc.org<mailto:jbiard at cicsnc.org>
> >>> <mailto:jbiard at cicsnc.org><mailto:jbiard at cicsnc.org>> wrote:
> >>>
> >>> Hi.
> >>>
> >>>
> >>> I've finally gotten back to this topic! The definitions
> >>> below call out an attribute named "direction" that is used
> >>> to specify the direction for positive values of the
> >>> different quantities. We may need to add a definition for
> >>> the attribute to the Conventions. The values and meanings
> >>> for the direction attribute are:
> >>>
> >>> roll: "clockwise" for positive right side up and
> >>> "anticlockwise" for positive right side down.
> >>> pitch: "clockwise" for positive nose up and "anticlockwise"
> >>> for positive nose down.
> >>> yaw: "clockwise" for positive nose right and "anticlockwise"
> >>> for positive nose left.
> >>> surge: "positive" for positive forward and "negative" for
> >>> positive backward.
> >>> sway: "positive" for positive left and "negative" for
> >>> positive right.
> >>> heave: "positive" for positive up and "negative" for
> >>> positive down.
> >>>
> >>> And here are the standard name definitions:
> >>>
> >>> platform_roll: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Roll is a rotation about
> >>> an axis (the X axis) that is perpendicular to the local
> >>> vertical axis (the Z axis) and is coplanar with the nominal
> >>> forward motion direction of the platform. Roll is relative
> >>> to the ?at rest? rotation of the platform with respect to
> >>> the X axis. The ?at rest? rotation of the platform may
> >>> change over time. The direction for positive values of roll
> >>> is specified by an attribute named direction. The value of
> >>> the direction attribute is "clockwise" if positive values of
> >>> roll represent the right side of the platform rising as
> >>> viewed by an observer on top of the platform facing forward.
> >>> The value of the direction attribute is "anticlockwise" if
> >>> positive values of roll represent the right side of the
> >>> platform falling. The directionality of roll values is
> >>> unspecified if no direction attribute is present.
> >>>
> >>> platform_pitch: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Pitch is a rotation about
> >>> an axis (the Y axis) that is perpendicular to both the local
> >>> vertical axis (the Z axis) and the nominal forward motion
> >>> direction of the platform. Pitch is relative to the ?at
> >>> rest? rotation of the platform with respect to the Y axis.
> >>> The ?at rest? rotation of the platform may change over time.
> >>> The direction for positive values of pitch is specified by
> >>> an attribute named direction. The value of the direction
> >>> attribute is "clockwise" if positive values of pitch
> >>> represent the front of the platform rising as viewed by an
> >>> observer on top of the platform facing forward. The value of
> >>> the direction attribute is "anticlockwise" if positive
> >>> values of pitch represent the front of the platform falling.
> >>> The directionality of pitch values is unspecified if no
> >>> direction attribute is present.
> >>>
> >>> platform_yaw: Platform is a structure or vehicle that serves
> >>> as a base for mounting sensors. Platforms include, but are
> >>> not limited to, satellites, aeroplanes, ships, buoys, ground
> >>> stations, and masts. Yaw is a rotation about the local
> >>> vertical axis (the Z axis). Yaw is relative to the ?at rest?
> >>> rotation of the platform with respect to the Z axis. The ?at
> >>> rest? rotation of the platform may change over time. The
> >>> direction for positive values of yaw is specified by an
> >>> attribute named direction. The value of the direction
> >>> attribute is "clockwise" if positive values of yaw represent
> >>> the front of the platform moving to the right as viewed by
> >>> an observer on top of the platform facing forward. The value
> >>> of the direction attribute is "anticlockwise" if positive
> >>> values of yaw represent the front of the platform moving to
> >>> the left. The directionality of yaw values is unspecified if
> >>> no direction attribute is present.
> >>>
> >>> platform_surge: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Surge is a displacement
> >>> along an axis (the X axis) that is perpendicular to the
> >>> local vertical axis (the Z axis) and is coplanar with the
> >>> nominal forward motion direction of the platform. Surge is
> >>> relative to the ?at rest? position of the platform with
> >>> respect to the X axis. The ?at rest? position of the
> >>> platform may change over time. The direction for positive
> >>> values of surge is specified by an attribute named
> >>> direction. The value of the direction attribute is
> >>> "positive" if positive values of surge represent the
> >>> platform moving forward as viewed by an observer on top of
> >>> the platform facing forward. The value of the direction
> >>> attribute is "negative" if positive values of surge
> >>> represent the platform moving backward. The directionality
> >>> of surge values is unspecified if no direction attribute is
> >>> present.
> >>>
> >>> platform_sway: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Sway is a displacement
> >>> along an axis (the Y axis) that is perpendicular to both the
> >>> local vertical axis (the Z axis) and the nominal forward
> >>> motion direction of the platform. Sway is relative to the
> >>> ?at rest? position of the platform with respect to the Y
> >>> axis. The ?at rest? position of the platform may change over
> >>> time. The direction for positive values of sway is
> >>> specified by an attribute named direction. The value of the
> >>> direction attribute is "positive" if positive values of sway
> >>> represent the platform moving left as viewed by an observer
> >>> on top of the platform facing forward. The value of the
> >>> direction attribute is "negative" if positive values of sway
> >>> represent the platform moving right. The directionality of
> >>> sway values is unspecified if no direction attribute is
> >>> present.
> >>>
> >>> platform_heave: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Heave is a displacement
> >>> along the local vertical axis (the Z axis). Heave is
> >>> relative to the ?at rest? position of the platform with
> >>> respect to the Z axis. The ?at rest? position of the
> >>> platform may change over time. The direction for positive
> >>> values of heave is specified by an attribute named
> >>> direction. The value of the direction attribute is
> >>> "positive" if positive values of heave represent the
> >>> platform moving up as viewed by an observer on top of the
> >>> platform facing forward. The value of the direction
> >>> attribute is "negative" if positive values of heave
> >>> represent the platform moving down. The directionality of
> >>> heave values is unspecified if no direction attribute is
> >>> present.
> >>>
> >>> platform_course: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Course is the clockwise
> >>> angle with respect to North of the nominal forward motion
> >>> direction of the platform.
> >>>
> >>> platform_orientation: Platform is a structure or vehicle
> >>> that serves as a base for mounting sensors. Platforms
> >>> include, but are not limited to, satellites, aeroplanes,
> >>> ships, buoys, ground stations, and masts. Orientation is the
> >>> clockwise angle with respect to North of the longitudinal
> >>> (front-to-back) axis of the platform, which may be different
> >>> than the platform course (see platform_course).
> >>>
> >>> platform_roll_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Roll rate is the rate of
> >>> rotation about an axis (the X axis) that is perpendicular to
> >>> the local vertical axis (the Z axis) and is coplanar with
> >>> the nominal forward motion direction of the platform. Roll
> >>> rate might not include changes in the ?at rest? rotation of
> >>> the platform, which may change over time. The direction for
> >>> positive values of roll rate is specified by an attribute
> >>> named direction. The value of the direction attribute is
> >>> "clockwise" if positive values of roll rate represent the
> >>> right side of the platform rising as viewed by an observer
> >>> on top of the platform facing forward. The value of the
> >>> direction attribute is "anticlockwise" if positive values of
> >>> roll rate represent the right side of the platform falling.
> >>> The directionality of roll rate values is unspecified if no
> >>> direction attribute is present.
> >>>
> >>> platform_pitch_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Pitch rate is the rate of
> >>> rotation about an axis (the Y axis) that is perpendicular to
> >>> both the local vertical axis (the Z axis) and the nominal
> >>> forward motion direction of the platform. Pitch rate might
> >>> not include changes in the ?at rest? rotation of the
> >>> platform, which may change over time. The direction for
> >>> positive values of pitch rate is specified by an attribute
> >>> named direction. The value of the direction attribute is
> >>> "clockwise" if positive values of pitch rate represent the
> >>> front of the platform rising as viewed by an observer on top
> >>> of the platform facing forward. The value of the direction
> >>> attribute is "anticlockwise" if positive values of pitch
> >>> rate represent the front of the platform falling. The
> >>> directionality of pitch rate values is unspecified if no
> >>> direction attribute is present.
> >>>
> >>> platform_yaw_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Yaw rate is the rate of
> >>> rotation about the local vertical axis (the Z axis). Yaw
> >>> rate might not include changes in the ?at rest? rotation of
> >>> the platform, which may change over time. The direction for
> >>> positive values of yaw rate is specified by an attribute
> >>> named direction. The value of the direction attribute is
> >>> "clockwise" if positive values of yaw rate represent the
> >>> front of the platform moving to the right as viewed by an
> >>> observer on top of the platform facing forward. The value of
> >>> the direction attribute is "anticlockwise" if positive
> >>> values of yaw rate represent the front of the platform
> >>> moving to the left. The directionality of yaw rate values is
> >>> unspecified if no direction attribute is present.
> >>>
> >>> platform_surge_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Surge rate is the rate of
> >>> displacement along an axis (the X axis) that is
> >>> perpendicular to the local vertical axis (the Z axis) and is
> >>> coplanar with the nominal forward motion direction of the
> >>> platform. Surge rate might not include changes in the ?at
> >>> rest? position of the platform, which may change over time.
> >>> The direction for positive values of surge rate is specified
> >>> by an attribute named direction. The value of the direction
> >>> attribute is "positive" if positive values of surge rate
> >>> represent the platform moving forward as viewed by an
> >>> observer on top of the platform facing forward. The value of
> >>> the direction attribute is "negative" if positive values of
> >>> surge rate represent the platform moving backward. The
> >>> directionality of surge rate values is unspecified if no
> >>> direction attribute is present.
> >>>
> >>> platform_sway_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Sway rate is the rate of
> >>> displacement along an axis (the Y axis) that is
> >>> perpendicular to both the local vertical axis (the Z axis)
> >>> and the nominal forward motion direction of the platform.
> >>> Sway rate might not include changes in the ?at rest?
> >>> position of the platform, which may change over time. The
> >>> direction for positive values of sway rate is specified by
> >>> an attribute named direction. The value of the direction
> >>> attribute is "positive" if positive values of sway rate
> >>> represent the platform moving left as viewed by an observer
> >>> on top of the platform facing forward. The value of the
> >>> direction attribute is "negative" if positive values of sway
> >>> rate represent the platform moving right. The directionality
> >>> of sway rate values is unspecified if no direction attribute
> >>> is present.
> >>>
> >>> platform_heave_rate: Platform is a structure or vehicle that
> >>> serves as a base for mounting sensors. Platforms include,
> >>> but are not limited to, satellites, aeroplanes, ships,
> >>> buoys, ground stations, and masts. Heave rate is the rate of
> >>> displacement along the local vertical axis (the Z axis).
> >>> Heave rate might not include changes in the ?at rest?
> >>> position of the platform, which may change over time. The
> >>> direction for positive values of heave rate is specified by
> >>> an attribute named direction. The value of the direction
> >>> attribute is "positive" if positive values of heave rate
> >>> represent the platform moving up as viewed by an observer on
> >>> top of the platform facing forward. The value of the
> >>> direction attribute is "negative" if positive values of
> >>> heave rate represent the platform moving down. The
> >>> directionality of heave rate values is unspecified if no
> >>> direction attribute is present.
> >>>
> >>>
> >>> Grace and peace,
> >>>
> >>>
> >>> Jim
> >>>
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> CF-metadata mailing list
> >>> CF-metadata at cgd.ucar.edu<mailto:CF-metadata at cgd.ucar.edu>
> >>><mailto:CF-metadata at cgd.ucar.edu><mailto:CF-metadata at cgd.ucar.edu>
> >>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata <https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=aEFMW9rC-ZIMfpnOfGtNzFe4-ieMDTvZ6FT1YaDGMzk&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=aEFMW9rC-ZIMfpnOfGtNzFe4-ieMDTvZ6FT1YaDGMzk&e=>
> >>>
> >>>
> >>> -- John Helly, University of California, San Diego / San
> >>>Diego Supercomputer Center / Scripps Institution of Oceanography
> >>>/ 760 840 8660 mobile /http://www.sdsc.edu/~hellyj <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.sdsc.edu_-257Ehellyj&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=t3yS7bwFeIbplaq59rJwZjTCr0nh-AAbloaOEdxwExk&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__www.sdsc.edu_-257Ehellyj&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=t3yS7bwFeIbplaq59rJwZjTCr0nh-AAbloaOEdxwExk&e=>
> >>> ORCID ID:orcid.org/0000-0002-3779-0603 <https://urldefense.proofpoint.com/v2/url?u=http-3A__orcid.org_0000-2D0002-2D3779-2D0603&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=6qTo44N_z3oeg5Su7f35nDe-nUQIgvAxqIFhSoDDwp4&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__orcid.org_0000-2D0002-2D3779-2D0603&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=6qTo44N_z3oeg5Su7f35nDe-nUQIgvAxqIFhSoDDwp4&e=>
> >>>
> >>>
> >>> -- CICS-NC
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cicsnc.org_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=x6gV6lXbbLkdSUM51Wmjdo76fXshvuWXWY9xQaf4LY4&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cicsnc.org_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=x6gV6lXbbLkdSUM51Wmjdo76fXshvuWXWY9xQaf4LY4&e=>
> >>> Visit us on
> >>> Facebook
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_cicsnc&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=QlBTCEJ-1zY8HYYE-fNxyp7W2lFizXxrb6KMRXUvDMg&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_cicsnc&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=QlBTCEJ-1zY8HYYE-fNxyp7W2lFizXxrb6KMRXUvDMg&e=>
> >>> *Jim Biard*
> >>> *Research Scholar*
> >>> Cooperative Institute for Climate and Satellites NC
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__cicsnc.org_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=FsLkqUXutAcXAPp22ZFFI6PUFlxtYMRYP65HFKMn6wQ&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__cicsnc.org_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=FsLkqUXutAcXAPp22ZFFI6PUFlxtYMRYP65HFKMn6wQ&e=>
> >>>
> >>> North Carolina State University
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__ncsu.edu_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=hkh8KblCtKqdp0zgN1OJbRBL0hfQw6tQwazcgNBCYCM&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__ncsu.edu_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=hkh8KblCtKqdp0zgN1OJbRBL0hfQw6tQwazcgNBCYCM&e=>
> >>>
> >>> NOAA National Centers for Environmental Information
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__ncdc.noaa.gov_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=lRLoOpPkER90BdM_TLc6QrJjgxz8V1gUTPLG5FHbLNk&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__ncdc.noaa.gov_&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=lRLoOpPkER90BdM_TLc6QrJjgxz8V1gUTPLG5FHbLNk&e=>
> >>>
> >>> /formerly NOAA?s National Climatic Data Center/
> >>> 151 Patton Ave, Asheville, NC 28801
> >>> e: jbiard at cicsnc.org<mailto:jbiard at cicsnc.org>
> >>><mailto:jbiard at cicsnc.org><mailto:jbiard at cicsnc.org>
> >>> o: +1 828 271 4900
> >>>
> >>> /Connect with us on Facebook for climate
> >>><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIclimate&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=IHiNI2oKTMXCgS6xh6TruNzh-tpMlrDgwrCErMx3Z-0&e=><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIclimate&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=IHiNI2oKTMXCgS6xh6TruNzh-tpMlrDgwrCErMx3Z-0&e=>
> >>> and ocean and geophysics
> >>><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIoceangeo&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=9i9XGUDVz9JclOsGWxIvmi1O2ulu_Ta_r0Ia8NwEbKM&e=><https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIoceangeo&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=9i9XGUDVz9JclOsGWxIvmi1O2ulu_Ta_r0Ia8NwEbKM&e=>
> >>> information, and follow us on Twitter at _at_NOAANCEIclimate
> >>><https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIclimate&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=XMw4fQ1_EhOoPwwVIa2gAsjDFQNzOIJ4sXv6DlAVq_4&e=><https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIclimate&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=XMw4fQ1_EhOoPwwVIa2gAsjDFQNzOIJ4sXv6DlAVq_4&e=>
> >>> and _at_NOAANCEIocngeo
> >>><https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIocngeo&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=rQdLOnos9rBDcbJXGsD7CgZgcW2493WTB3e8bO8bqVo&e=><https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIocngeo&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=rQdLOnos9rBDcbJXGsD7CgZgcW2493WTB3e8bO8bqVo&e=>.
> >>> /
> >>>
> >>>
> >>> _______________________________________________
> >>> CF-metadata mailing list
> >>> CF-metadata at cgd.ucar.edu<mailto:CF-metadata at cgd.ucar.edu>
> >>><mailto:CF-metadata at cgd.ucar.edu><mailto:CF-metadata at cgd.ucar.edu>
> >>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
> >>><https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=aEFMW9rC-ZIMfpnOfGtNzFe4-ieMDTvZ6FT1YaDGMzk&e=><https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMFaQ&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=V30oufQn7eoscpwV3fkPj-Rzw4SsBmtwWpTQ8PZaDgQ&s=aEFMW9rC-ZIMfpnOfGtNzFe4-ieMDTvZ6FT1YaDGMzk&e=>
> >>>
> >>>
> >>>_______________________________________________
> >>>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
> >>>
> >>>
> >>>--
> >>>Kenneth E. Kehoe
> >>> Research Associate - University of Oklahoma
> >>> Cooperative Institute for Mesoscale Meteorological Studies
> >>> ARM Climate Research Facility - Data Quality Office
> >>> e-mail: kkehoe at ou.edu<mailto:kkehoe at ou.edu> | Office:
> >>>303-497-4754 | Cell: 405-826-0299
> >>>
> >>>
> >>>
> >>>_______________________________________________
> >>>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
> >>>
> >>>
> >>>----- End forwarded message -----
> >>>_______________________________________________
> >>>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
> >>>
> >>>
> >>>--
> >>>[CICS-NC] <http://www.cicsnc.org/> Visit us on
> >>>Facebook <http://www.facebook.com/cicsnc> Jim Biard
> >>>Research Scholar
> >>>Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/>
> >>>North Carolina State University <http://ncsu.edu/>
> >>>NOAA National Centers for Environmental Information <http://ncdc.noaa.gov/>
> >>>formerly NOAA?s National Climatic Data Center
> >>>151 Patton Ave, Asheville, NC 28801
> >>>e: jbiard at cicsnc.org<mailto:jbiard at cicsnc.org>
> >>>o: +1 828 271 4900
> >>>
> >>>Connect with us on Facebook for
> >>>climate<https://www.facebook.com/NOAANCEIclimate> and ocean and
> >>>geophysics<https://www.facebook.com/NOAANCEIoceangeo> information,
> >>>and follow us on Twitter at
> >>>_at_NOAANCEIclimate<https://twitter.com/NOAANCEIclimate> and
> >>>_at_NOAANCEIocngeo<https://twitter.com/NOAANCEIocngeo>.
> >>>
> >>>________________________________
> >>>This message (and any attachments) is for the recipient only. NERC
> >>>is subject to the Freedom of Information Act 2000 and the contents
> >>>of this email and any reply you make may be disclosed by NERC
> >>>unless it is exempt from release under the Act. Any material
> >>>supplied to NERC may be stored in an electronic records management
> >>>system.
> >>>________________________________
> >>
> >>
> >>_______________________________________________
> >>CF-metadata mailing list
> >>CF-metadata at cgd.ucar.edu
> >>http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
> >----- End forwarded message -----
> >_______________________________________________
> >CF-metadata mailing list
> >CF-metadata at cgd.ucar.edu
> >http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>
> --
> CICS-NC <http://www.cicsnc.org/> Visit us on
> Facebook <http://www.facebook.com/cicsnc> *Jim Biard*
> *Research Scholar*
> Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/>
> North Carolina State University <http://ncsu.edu/>
> NOAA National Centers for Environmental Information <http://ncdc.noaa.gov/>
> /formerly NOAA?s National Climatic Data Center/
> 151 Patton Ave, Asheville, NC 28801
> e: jbiard at cicsnc.org <mailto:jbiard at cicsnc.org>
> o: +1 828 271 4900
>
> /Connect with us on Facebook for climate
> <https://www.facebook.com/NOAANCEIclimate> and ocean and geophysics
> <https://www.facebook.com/NOAANCEIoceangeo> information, and follow
> us on Twitter at _at_NOAANCEIclimate
> <https://twitter.com/NOAANCEIclimate> and _at_NOAANCEIocngeo
> <https://twitter.com/NOAANCEIocngeo>. /
>
>
> _______________________________________________
> CF-metadata mailing list
> CF-metadata at cgd.ucar.edu
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
----- End forwarded message -----
Received on Tue Sep 04 2018 - 08:18:47 BST
