Determine the speed of profiling - Revision history

CynthiaBluteau: Categorization

2021-11-23T15:30:26Z

Categorization

← Older revision		Revision as of 15:30, 23 November 2021
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	For such unusual conditions it may be wise to set the speed of profiling to a constant equal to the nominal vertical velocity of your profiler, which you can determine by taking a few profiles in quiescent waters.		For such unusual conditions it may be wise to set the speed of profiling to a constant equal to the nominal vertical velocity of your profiler, which you can determine by taking a few profiles in quiescent waters.

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	return to [[Flow chart for shear probes]]		return to [[Flow chart for shear probes]]
			[[Category:Shear probes]]

Rolf at 20:20, 18 November 2021

2021-11-18T20:20:19Z

← Older revision		Revision as of 20:20, 18 November 2021
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	The rate of change of pressure is often used to determine the speed of profiling of a vertical profiler.		The rate of change of pressure is often used to determine the speed of profiling of a vertical profiler.
	Likewise, the rate of change of pressure, the pitch angle and the angle of attack are often used to determine the speed of a ~~glide~~.		Likewise, the rate of change of pressure, the pitch angle and the angle of attack are often used to determine the speed of a glider.
	There are circumstances when rate of change of pressure may not provide a reliable estimate of the speed of profiling ''with respect to the local water surrounding'' an instrument.		There are circumstances when rate of change of pressure may not provide a reliable estimate of the speed of profiling ''with respect to the local water surrounding'' an instrument.
	In ~~vinously~~ turbulent waters that contains eddies with scales larger than your instrument, the up- and down-drafts created ~~might~~ modify the vertical velocity of your instrument with respect to an inertial (or fixed-earth) reference.		In vigorously turbulent waters that contains eddies with scales larger than your instrument, the up- and down-drafts created by these eddies may modify the vertical velocity of your instrument with respect to an inertial (or fixed-earth) reference.
	For example, if an updraft equals the nominal vertical speed of a ~~profile~~, the profiler will stall, and its rate of change of pressure will go to zero.		For example, if an updraft equals the nominal vertical speed of a profiler, the profiler will stall, and its rate of change of pressure will go to zero.
	However, there is still flow past the shear probes and the speed of this flow will be close to the nominal vertical speed of your instrument because most profilers adjust quickly (in about one body length if travel) to their surrounding conditions.		However, there is still flow past the shear probes and the speed of this flow will be close to the nominal vertical speed of your instrument because most profilers adjust quickly (in about one body length of travel) to their surrounding conditions.
	You can also get an erroneous indication of the speed of profiling from the rate of change of pressure when your instrument travels through a soliton.		You can also get an erroneous indication of the speed of profiling from the rate of change of pressure when your instrument travels through a soliton.
	In fact, anicdodal information (L. St. Laurent, personal communication) indicates that a profiler may momentarily reverse its course when traveling through a very energetic soliton.		In fact, anicdodal information (L. St. Laurent, personal communication) indicates that a profiler may momentarily reverse its course when traveling through a very energetic soliton.
	For such unusual conditions it may be wise to set the speed of profiling to a constant equal to the nominal vertical velocity of your profiler.		For such unusual conditions it may be wise to set the speed of profiling to a constant equal to the nominal vertical velocity of your profiler, which you can determine by taking a few profiles in quiescent waters.

	return to [[Flow chart for shear probes]]		return to [[Flow chart for shear probes]]

Rolf at 20:16, 18 November 2021

2021-11-18T20:16:47Z

← Older revision		Revision as of 20:16, 18 November 2021
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	# Using the speed recorded by an independent instrument after its record has been carefully aligned in time with the shear-probe data.		# Using the speed recorded by an independent instrument after its record has been carefully aligned in time with the shear-probe data.

			The rate of change of pressure is often used to determine the speed of profiling of a vertical profiler.
			Likewise, the rate of change of pressure, the pitch angle and the angle of attack are often used to determine the speed of a glide.
			There are circumstances when rate of change of pressure may not provide a reliable estimate of the speed of profiling ''with respect to the local water surrounding'' an instrument.
			In vinously turbulent waters that contains eddies with scales larger than your instrument, the up- and down-drafts created might modify the vertical velocity of your instrument with respect to an inertial (or fixed-earth) reference.
			For example, if an updraft equals the nominal vertical speed of a profile, the profiler will stall, and its rate of change of pressure will go to zero.
			However, there is still flow past the shear probes and the speed of this flow will be close to the nominal vertical speed of your instrument because most profilers adjust quickly (in about one body length if travel) to their surrounding conditions.
			You can also get an erroneous indication of the speed of profiling from the rate of change of pressure when your instrument travels through a soliton.
			In fact, anicdodal information (L. St. Laurent, personal communication) indicates that a profiler may momentarily reverse its course when traveling through a very energetic soliton.
			For such unusual conditions it may be wise to set the speed of profiling to a constant equal to the nominal vertical velocity of your profiler.

	return to [[Flow chart for shear probes]]		return to [[Flow chart for shear probes]]

Aleboyer at 03:23, 5 November 2021

2021-11-05T03:23:03Z

← Older revision		Revision as of 03:23, 5 November 2021
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	# Using a constant speed.		# Using a constant speed.
	# Using the speed recorded by an independent instrument after its record has been carefully aligned in time with the shear-probe data.		# Using the speed recorded by an independent instrument after its record has been carefully aligned in time with the shear-probe data.



			return to [[Flow chart for shear probes]]

Rolf at 22:31, 14 July 2021

2021-07-14T22:31:18Z

← Older revision		Revision as of 22:31, 14 July 2021
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	The speed of profiling can be determined in a variety of different methods ~~but it~~ must be determined because it is required for the conversion of the shear-probe samples into physical units. Methods for determining the speed of profiling include, but are not limited to:		The speed of profiling can be determined with a variety of different methods.
			It must be determined because it is required for the conversion of the shear-probe samples into physical units and for transforming frequency spectra into wavenumber spectra.
			Methods for determining the speed of profiling include, but are not limited to:
	# Using the rate-of-change of pressure for a vertical profiler.		# Using the rate-of-change of pressure for a vertical profiler.
	# Using the rate-of-change of pressure, the pitch angle, and the angle of attack for a glider.		# Using the rate-of-change of pressure, the pitch angle, and the angle of attack for a glider.
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	# Using an onboard current meter.		# Using an onboard current meter.
	# Using a constant speed.		# Using a constant speed.
	# Using the speed recorded by an independent instrument after ~~such data have~~ been carefully aligned in time with the shear-probe data.		# Using the speed recorded by an independent instrument after its record has been carefully aligned in time with the shear-probe data.

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2021-04-22T13:59:55Z

Created page with "The speed of profiling can be determined in a variety of different methods but it must be determined because it is required for the conversion of the shear-probe samples into..."

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The speed of profiling can be determined in a variety of different methods but it must be determined because it is required for the conversion of the shear-probe samples into physical units. Methods for determining the speed of profiling include, but are not limited to:
# Using the rate-of-change of pressure for a vertical profiler.
# Using the rate-of-change of pressure, the pitch angle, and the angle of attack for a glider.
# Using a flight model for a glider.
# Using an onboard current meter.
# Using a constant speed.
# Using the speed recorded by an independent instrument after such data have been carefully aligned in time with the shear-probe data.