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

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. An important feature of the method is the fact that the cloud optical thickness and cloud effective radius are found using the standard homogeneous cloud retrieval and then the retrievals are improved assuming the type of the droplet effective radius profile.

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Solar occultation with SCIAMACHY: algorithm description and first validation

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-5-17-2005 ◽

2005 ◽

Vol 5 (1) ◽

pp. 17-66 ◽

Cited By ~ 1

Author(s):

J. Meyer ◽

A. Bracher ◽

A. Rozanov ◽

A. C. Schlesier ◽

H. Bovensmann ◽

...

Keyword(s):

Vertical Profile ◽

Estimation Method ◽

Optimal Estimation ◽

Trace Gas ◽

Transmission Spectra ◽

Atmospheric Transmission ◽

Gas Concentration ◽

Solar Occultation ◽

First Results ◽

The Vertical Distribution

Abstract. This presentation concentrates on solar occultation measurements with the spaceborne spectrometer SCIAMACHY in the UV-Vis wavelength range. Solar occultation measurements provide unique information about the vertical distribution of atmospheric constituents. For retrieval of vertical trace gas concentration profiles, an algorithm has been developed based on the optimal estimation method. The forward model is capable to simulate the extinction signals of different species as they occur in atmospheric transmission spectra obtained from occultation measurements. Furthermore, correction algorithms have been implemented to address shortcomings of the tangent height pre-processing and inhomogeneities of measured solar spectra. First results of O3 and NO2 vertical profile retrievals have been validated with data from ozone sondes and satellite based occultation instruments. The validation shows very promising results for SCIAMACHY O3 and NO2 values between 15 to 35 km with errors in the order of 10% and 15%, respectively.

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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

ICES Journal of Marine Science ◽

10.1093/icesjms/fsl016 ◽

2006 ◽

Vol 64 (1) ◽

pp. 18-30 ◽

Cited By ~ 2

Author(s):

P. Pepin ◽

K. A. Curtis ◽

P. V. R. Snelgrove ◽

B. de Young ◽

J. A. Helbig

Keyword(s):

Vertical Distribution ◽

Water Column ◽

Vertical Profile ◽

Negative Binomial ◽

Optimal Estimation ◽

Eddy Diffusivity ◽

Model Parameters ◽

Error Structure ◽

The Vertical Distribution ◽

Hippoglossoides Platessoides

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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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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Solar occultation with SCIAMACHY: algorithm description and first validation

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-1589-2005 ◽

2005 ◽

Vol 5 (6) ◽

pp. 1589-1604 ◽

Cited By ~ 17

Author(s):

J. Meyer ◽

A. Bracher ◽

A. Rozanov ◽

A. C. Schlesier ◽

H. Bovensmann ◽

...

Keyword(s):

Vertical Profile ◽

Estimation Method ◽

Optimal Estimation ◽

Trace Gas ◽

Transmission Spectra ◽

Atmospheric Transmission ◽

Gas Concentration ◽

Solar Occultation ◽

First Results ◽

The Vertical Distribution

Abstract. This presentation concentrates on solar occultation measurements with the spaceborne spectrometer SCIAMACHY in the UV-Vis wavelength range. Solar occultation measurements provide unique information about the vertical distribution of atmospheric constituents. For retrieval of vertical trace gas concentration profiles, an algorithm has been developed based on the optimal estimation method. The forward model is capable of simulating the extinction signals of different species as they occur in atmospheric transmission spectra obtained from occultation measurements. Furthermore, correction algorithms have been implemented to address shortcomings of the tangent height pre-processing and inhomogeneities of measured solar spectra. First results of O3 and NO2 vertical profile retrievals have been validated with data from ozone sondes and satellite based occultation instruments. The validation shows very promising results for SCIAMACHY O3 and NO2 values between 15 to 35km with errors of the order of 10% and 15%, respectively.

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Discussion of the Kelso paper on “A procedure for the determination of the vertical distribution of the electron density in the ionosphere”

Journal of Geophysical Research Atmospheres ◽

10.1029/jz058i001p00117 ◽

1953 ◽

Vol 58 (1) ◽

pp. 117-118 ◽

Cited By ~ 4

Author(s):

L. A. Manning

Keyword(s):

Vertical Distribution ◽

Electron Density ◽

The Vertical Distribution

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Pollen-ovule relation in Adesmia tristis and reflections on the seed–ovule ratio by interaction with pollinators in two vertical strata

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201420130213 ◽

2014 ◽

Vol 86 (3) ◽

pp. 1327-1336 ◽

Cited By ~ 3

Author(s):

NADILSON R. FERREIRA ◽

LUCIA B. FRANKE ◽

BETINA BLOCHTEIN

Keyword(s):

Vertical Distribution ◽

Breeding System ◽

Vertical Profile ◽

Rio Grande ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Catholic University ◽

Pollination Deficit ◽

Foraging Pattern ◽

The Vertical Distribution

The vertical distribution of pollinators is an important component in the foraging pattern of plants strata, and it influences the reproductive system (pollen/ovule ratio) and seed/ovule ratio. Niches in two different strata from Adesmia tristis Vogel were evaluated in these aspects. This plant is an endemic shrub from the Campos de Cima da Serra in Southern Brazil. The studies were carried out from January 2010, to January 2011, at Pró-Mata/PUCRS (Catholic University of Rio Grande do Sul) (29°27′-29°35′S and 50°08′-50°15′W), São Francisco de Paula, sate of Rio Grande do Sul, Brazil. Breeding system of A. tristis is mandatory allogamy. The vertical profile in A. tristis has differentiated foraging niches among the most common pollinators. Bees of Megachile genus forage in the upper stratum, and representative bees of the Andrenidae family explore the lower stratum. The upper stratum of the vertical profile had more contribution to seed production. Adesmia tristis showed evidence of pollination deficit.

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Validation of optimal estimation method retrievals of middle atmospheric temperature

EPJ Web of Conferences ◽

10.1051/epjconf/201817603001 ◽

2018 ◽

Vol 176 ◽

pp. 03001

Author(s):

Ali Jalali ◽

R. J. Sica ◽

Alexander Haefele

Keyword(s):

Quantitative Determination ◽

Estimation Method ◽

Optimal Estimation ◽

Atmospheric Temperature ◽

Measurement Noise ◽

Traditional Methods ◽

Lidar Measurements ◽

Random Uncertainties

OEM (Optimal Estimation Method) retrievals of temperature from lidar measurements are robust and practical (Sica and Haefele, 2015). They offer significant improvements over traditional methods. We will show a climatology of +360 nights of measurements from the Purple Crow Lidar and the improvements offered using an OEM, including the quantitative determination of the top altitude of the retrieval and the evaluation of the various systematic and random uncertainties due to measurement noise.

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Application of Number-Size (N-S) Fractal Model to Quantify of the Vertical Distributions of Cu and Mo in Nowchun Porphyry Deposit (Kerman, Se Iran) / Zastosowanie modelu fraktalnego n-s (liczba-rozmiar) do ilościowego określenia pionowego rozkładu Cu i Mo w złożu porfirowym (Kerman, Iran)

Archives of Mining Sciences ◽

10.2478/amsc-2013-0006 ◽

2013 ◽

Vol 58 (1) ◽

pp. 89-105 ◽

Cited By ~ 2

Author(s):

Lili Daneshvar Saein ◽

Iraj Rasa ◽

Nematolah Rashidnejad Omran ◽

Parviz Moarefvand ◽

Peyman Afzal ◽

...

Keyword(s):

Vertical Distribution ◽

Mineral Exploration ◽

Fractal Model ◽

Skewed Distribution ◽

Threshold Values ◽

Multimodal Distribution ◽

Porphyry Deposit ◽

Vertical Distributions ◽

The Vertical Distribution

Determination of the vertical distribution of geochemical elemental concentrations is of fundamental importance in mineral exploration. In this paper, eight mineralized boreholes from the Nowchun Cu-Mo porphyry deposit, SE Iran, were used to identify of the vertical distribution directional properties of Cu and Mo values using number-size (N-S) fractal model. The vertical distributions of Cu and Mo in the mineralized boreholes show a positively skewed distribution in the former and a multimodal distribution in the latter types. Elemental threshold values for the mineralized boreholes were computed by fractal model and compared with the statistical methods based on the data obtained from chemical analysis of samples. Elemental distributions are not normal in these boreholes and their median equal to Cu and Mo thresholds. The results of N-S fractal analysis reveal that Cu and Mo values in mineralized boreholes are multifractals in nature. There are at least three geochemical populations for Cu and Mo in the boreholes and Cu and Mo thresholds have ranges between 0.07%-0.3% and 50-200 ppm, respectively. The results obtained by N-S fractal model were compared with geological observations in the boreholes. Major Cu and Mo enrichment correlated by monzonitic rocks and high amounts of observed Cu and Mo ores (Chalcopyrite and molybdenite) in the boreholes.

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