Optimal estimation of catch by the continuous underway fish egg sampler based on a model of the vertical distribution of American plaice (Hippoglossoides platessoides) eggs

Abstract Pepin, P., Curtis, K.A., Snelgrove, P.V.R., de Young, B., and Helbig, J.A. 2007. Optimal estimation of catch by the continous underway fish egg sampler based on a model of the vertical distribution of American plaice (Hippoglossoides platessoides) eggs – ICES Journal of Marine Science, 64, 18–30. We investigate how the vertical stratification of the water column (specifically density) affects predictions of the catch of American plaice eggs (Hipploglossoides platessoides) from a fixed-depth sampler [the continuous underway fish egg sampler (CUFES)] relative to the integrated abundance in the water column measured in bongo tows. A steady-state model of the vertical distribution of fish eggs coupled with a simple model of the vertical profile of eddy diffusivity (i.e. mixing) is applied. Key model parameters are estimated through optimization of a one-to-one relationship between predicted and observed catches fit, using a generalized linear model with a Poisson, negative binomial, or gamma error structure. The incorporation of data on the vertical structure of the water column significantly improved the ability to forecast CUFES catches when using Poisson or negative binomial error structure, but not using a gamma distribution. Optimal maximum likelihood parameter estimates for eddy diffusivity and egg buoyancy fell within the range of expected values. The degree of uncertainty in the parameterization of eddy diffusivity suggests, however, that greater understanding of the forces that determine the vertical profile of mixing is critical to achieving strong predictive capabilities. The inverse problem of predicting integrated abundance from CUFES catches did not benefit from the environmental-driven model because of the high uncertainty in the catches from the CUFES.

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Information operator approach applied to the retrieval of the vertical distribution of atmospheric constituents from ground-based high-resolution FTIR measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-5-161-2012 ◽

2012 ◽

Vol 5 (1) ◽

pp. 161-180 ◽

Cited By ~ 4

Author(s):

C. Senten ◽

M. De Mazière ◽

G. Vanhaelewyn ◽

C. Vigouroux

Keyword(s):

Vertical Distribution ◽

Tikhonov Regularization ◽

Estimation Method ◽

Optimal Estimation ◽

Atmospheric Composition ◽

High Spectral Resolution ◽

Retrieval Algorithm ◽

Operator Approach ◽

Information Operator ◽

The Vertical Distribution

Abstract. The analysis of high spectral resolution Fourier Transform infrared (FTIR) solar absorption spectra is an important issue in remote sensing. If this is done carefully, one can obtain information, not only about the total column abundances, but also about the vertical distribution of various constituents in the atmosphere. This work introduces the application of the information operator approach for extracting vertical profile information from ground-based FTIR measurements. The algorithm is implemented and tested within the well-known retrieval code SFIT2, adapting the optimal estimation method such as to take into account only the significant contributions to the solution. In particular, we demonstrate the feasibility of the method in an application to ground-based FTIR spectra taken in the framework of the Network for the Detection of Atmospheric Composition Change (NDACC) at Ile de La Réunion (21° S, 55° E). A thorough comparison is made between the original optimal estimation method, Tikhonov regularization and this alternative retrieval algorithm, regarding information content, retrieval robustness and corresponding full error budget evaluation for the target species ozone (O3), nitrous oxide (N2O), methane (CH4), and carbon monoxide (CO). It is shown that the information operator approach performs well and in most cases yields both a better accuracy and stability than the optimal estimation method. Additionally, the information operator approach has the advantage of being less sensitive to the choice of a priori information than the optimal estimation method and Tikhonov regularization. On the other hand, in general the Tikhonov regularization results seem to be slightly better than the optimal estimation method and information operator approach results when it comes to error budgets and column stability.

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Dependence of the vertical distribution of bromine monoxide in the lower troposphere on meteorological factors such as wind speed and stability

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-2119-2015 ◽

2015 ◽

Vol 15 (4) ◽

pp. 2119-2137 ◽

Cited By ~ 25

Author(s):

P. K. Peterson ◽

W. R. Simpson ◽

K. A. Pratt ◽

P. B. Shepson ◽

U. Frieß ◽

...

Keyword(s):

Wind Speed ◽

Vertical Distribution ◽

Degrees Of Freedom ◽

Atmospheric Stability ◽

Lower Troposphere ◽

Optimal Estimation ◽

Vertical Column ◽

Vertical Column Density ◽

Halogen Activation ◽

The Vertical Distribution

Abstract. Multiple axis differential absorption spectroscopy (MAX-DOAS) measurements of bromine monoxide (BrO) probed the vertical structure of halogen activation events during March–May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two quantities: the integrated column from the surface through 200 m (VCD200 m), and the lower tropospheric vertical column density (LT-VCD), which represents the integrated column of BrO from the surface through 2 km. The percentage of lower tropospheric BrO in the lowest 200 m was found to be highly variable ranging from shallow layer events, where BrO is present primarily in the lowest 200 m, to distributed column events where BrO is observed at higher altitudes. The highest observed LT-VCD events occurred when BrO was distributed throughout the lower troposphere, rather than concentrated near the surface. Atmospheric stability in the lowest 200 m influenced the percentage of LT-VCD that is in the lowest 200 m, with inverted temperature structures having a first-to-third quartile range (Q1–Q3) of VCD200 m/LT-VCD from 15–39%, while near-neutral-temperature structures had a Q1–Q3 range of 7–13%. Data from this campaign show no clear influence of wind speed on either lower tropospheric bromine activation (LT-VCD) or the vertical distribution of BrO, while examination of seasonal trends and the temperature dependence of the vertical distribution supported the conclusion that the atmospheric stability affects the vertical distribution of BrO.

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Information operator approach applied to the retrieval of the vertical distribution of atmospheric constituents from ground-based high-resolution FTIR measurements

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-4-3739-2011 ◽

2011 ◽

Vol 4 (3) ◽

pp. 3739-3785

Author(s):

C. Senten ◽

M. De Mazière ◽

G. Vanhaelewyn ◽

C. Vigouroux

Keyword(s):

Vertical Distribution ◽

Tikhonov Regularization ◽

Estimation Method ◽

Optimal Estimation ◽

High Spectral Resolution ◽

Tikhonov Regularization Method ◽

Retrieval Algorithm ◽

Operator Approach ◽

Information Operator ◽

The Vertical Distribution

Abstract. The analysis of high spectral resolution Fourier Transform infrared (FTIR) solar absorption spectra is an important issue in remote sensing. If this is done carefully, one can obtain information, not only about the total column abundances, but also about the vertical distribution of various constituents in the atmosphere. This work introduces the application of the information operator approach for extracting vertical profile information from ground-based FTIR measurements. The algorithm is implemented and tested within the well-known retrieval code SFIT2, adapting the optimal estimation method such as to take into account only the significant contributions to the solution. In particular, we demonstrate the feasibility of the method in an application to ground-based FTIR spectra taken in the frame of the Network for the Detection of Atmospheric Composition Change (NDACC) at Ile de La Réunion (21° S, 55° E). A thorough comparison is made between the original optimal estimation method and this alternative retrieval algorithm, regarding information content, retrieval robustness and corresponding full error budget evaluation for the target species ozone (O3), nitrous oxide (N2O), methane (CH4), and carbon monoxide (CO). For O3 and CH4, a comparison with the Tikhonov regularization method has also been made. It is shown that the information operator approach performs well and in most cases yields both a better accuracy and stability than the optimal estimation method. Additionally, the information operator approach has the advantage of being less sensitive to the choice of a priori information. The Tikhonov regularization results seem to be situated between both methods' results, as to profile retrievals, error budgets and column stability.

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Meteorological controls on the vertical distribution of bromine monoxide in the lower troposphere

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-23949-2014 ◽

2014 ◽

Vol 14 (17) ◽

pp. 23949-23994

Author(s):

P. K. Peterson ◽

W. R. Simpson ◽

K. A. Pratt ◽

P. B. Shepson ◽

U. Frieß ◽

...

Keyword(s):

Vertical Distribution ◽

Degrees Of Freedom ◽

Atmospheric Stability ◽

Lower Troposphere ◽

Optimal Estimation ◽

Vertical Column ◽

Shallow Layer ◽

Vertical Column Density ◽

Halogen Activation ◽

The Vertical Distribution

Abstract. Multiple axis differential absorption spectroscopy (MAX-DOAS) measurements of bromine monoxide (BrO) probed the vertical structure of halogen activation events during March–May 2012 at Barrow, Alaska. An analysis of the BrO averaging kernels and degrees of freedom obtained by optimal-estimation-based inversions from raw MAX-DOAS measurements reveals the information is best represented by reducing the retrieved BrO profile to two quantities, the integrated column from the surface through 200 m (VCD200 m), and the lower tropospheric vertical column density (LT-VCD) which represents the integrated column of BrO from the surface through 2 km. The percentage of lower-tropospheric BrO in the lowest 200 m was found to be highly variable ranging from shallow layer events, where BrO is present primarily in the lowest 200 m to distributed column events where BrO is observed at higher altitudes. The highest observed LT-VCD events occurred when BrO was distributed throughout the lower troposphere, rather than concentrated near the surface. Atmospheric stability in the lowest 200 m influenced the percentage of LT-VCD that is in the lowest 200 m, with inverted temperature structures having a first-to-third quartile range (Q1–Q3) of VCD200 m/LT-VCD from 15–39% while near neutral temperature structures had a Q1–Q3 range of 7–13%. Data from this campaign show no clear influence of wind speed on either lower-tropospheric bromine activation (LT-VCD) or the vertical distribution of BrO, while examination of seasonal trends and the temperature dependence of the vertical distribution supported the conclusion that the atmospheric stability affects the vertical distribution of BrO.

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Droplet vertical sizing in warm clouds using passive optical measurements from a satellite

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-4-5597-2011 ◽

2011 ◽

Vol 4 (4) ◽

pp. 5597-5629 ◽

Cited By ~ 3

Author(s):

A. Kokhanovsky ◽

V. V. Rozanov

Keyword(s):

Vertical Distribution ◽

Vertical Profile ◽

Estimation Method ◽

Optimal Estimation ◽

Effective Radius ◽

Optical Measurements ◽

Weighting Functions ◽

Near Ir ◽

The Vertical Distribution

Abstract. In this paper a new algorithm for the determination of the vertical distribution of the droplet effective radius in shallow warm clouds is proposed. The method is based on the fact that the spectral top-of-atmosphere reflectance in the near IR spectral range depends on the vertical profile of the effective radius of droplets. The retrieval is based on the optimal estimation method and direct radiative transfer calculations of respective weighting functions. The applications of the method both to synthetic and satellite data are presented.

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