Ensemble Transform with 3D Rescaling Initialization Method

Abstract The ensemble transform with rescaling (ETR) method has been used to produce fast-growing components of analysis error in the NCEP Global Ensemble Forecast System (GEFS). The rescaling mask contained in the ETR method constrains the amplitude of perturbations to reflect regional variations of analysis error. However, because of a lack of suitable three-dimensional (3D) analysis error estimation, in the operational GEFS the mask is based on the estimated analysis error at 500 hPa and is not flow dependent but changes monthly. With the availability of an ensemble-based data assimilation system at NCEP, a 3D mask can be computed. This study generates initial perturbations by the ensemble transform with 3D rescaling (ET_3DR) and compares the performance with the ETR. Meanwhile, the ET_3DR is also applied within the ensemble Kalman filter (EnKF) method (hereafter EnKF_3DR). Results from a set of experiments indicate that the 3D mask suppresses perturbations less in unstable regions. Relative to the ETR, the large amplitudes of the ET_3DR initial perturbations at 500 hPa better reflect areas of baroclinic instability over the extratropics and deep convection over the tropics. Furthermore, the maxima of the vertical distribution for the ET_3DR initial perturbations correspond to the heights of the subtropical westerly and tropical easterly jet regions. Such perturbations produce faster spread growths. Results with EnKF_3DR also show benefits from an orthonormalization by the ensemble transform algorithm and amplitude constraint by the 3D mask rescaling. Thus, the EnKF_3DR forecasts outperform the EnKF.

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Explanation for the increase in high altitude water on Mars observed by NOMAD during the 2018 global dust storm

10.5194/egusphere-egu2020-14498 ◽

2020 ◽

Author(s):

Lori Neary ◽

Frank Daerden ◽

Shohei Aoki ◽

James Whiteway ◽

Robert Todd Clancy ◽

...

Keyword(s):

High Altitude ◽

Water Vapour ◽

Dust Storm ◽

General Circulation ◽

Three Dimensional ◽

Circulation Model ◽

Atmospheric Escape ◽

Mars Model ◽

The Tropics ◽

The Vertical Distribution

Using the GEM-Mars three-dimensional general circulation model (GCM), we examine the mechanism responsible for the enhancement of water vapour in the upper atmosphere as measured by the Nadir and Occultation for MArs Discovery (NOMAD) instrument onboard ExoMars Trace Gas Orbiter (TGO) during the 2018 global dust storm on Mars.Experiments with different prescribed vertical profiles of dust show that when more dust is present higher in the atmosphere, the temperature increases and the amount of water ascending over the tropics is not limited by saturation until reaching heights of 70-100 km. The warmer temperatures allow more water to ascend to the mesosphere. The simulation of enhanced high-altitude water abundances is very sensitive to the vertical distribution of the dust prescribed in the model.The GEM-Mars model includes gas-phase photochemistry, and these simulations show how the increased water vapour over the 40-100 km altitude range results in the production of high-altitude atomic hydrogen which can be linked to atmospheric escape.

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A Local Formulation of the Ensemble Transform (ET) Analysis Perturbation Scheme

Weather and Forecasting ◽

10.1175/2010waf2222359.1 ◽

2010 ◽

Vol 25 (3) ◽

pp. 985-993 ◽

Cited By ~ 29

Author(s):

Justin McLay ◽

Craig H. Bishop ◽

Carolyn A. Reynolds

Keyword(s):

Weather Prediction ◽

Error Variance ◽

Numerical Weather Prediction Model ◽

Perturbation Scheme ◽

Ensemble Transform Kalman Filter ◽

Analysis Error ◽

Formulation Analysis ◽

The Tropics ◽

Performance Gains ◽

Ensemble Transform

Abstract Following ideas from the local ensemble transform Kalman filter, a local formulation of the ensemble transform (ET) analysis perturbation scheme is developed by partitioning the numerical weather prediction model domain into latitude bands or latitude–longitude blocks. In comparison with analysis perturbations from the original “global” ET formulation, analysis perturbations from the “banded” or “block” ET formulations are much more consistent with estimates of analysis error variance. Banded or block ET forecast ensembles also perform better under a variety of verification metrics than do global ET forecast ensembles. Substantial performance gains are observed for both the midlatitudes and the tropics. A local ET is scheduled to be made operational at the Fleet Numerical Meteorology and Oceanography Center.

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Transport pathways from the Asian monsoon anticyclone to the stratosphere

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-25981-2015 ◽

2015 ◽

Vol 15 (18) ◽

pp. 25981-26023 ◽

Cited By ~ 1

Author(s):

H. Garny ◽

W. J. Randel

Keyword(s):

Large Scale ◽

Asian Monsoon ◽

Deep Convection ◽

Three Dimensional ◽

Reanalysis Data ◽

Vertical Transport ◽

Heating Rates ◽

Transport Pathways ◽

Northern Summer ◽

The Tropics

Abstract. Transport pathways of air originating in the upper tropospheric Asian monsoon anticyclone are investigated based on three-dimensional trajectories. The Asian monsoon anticyclone emerges in response to persistent deep convection over India and southeast Asia in northern summer, and this convection is associated with rapid transport from the surface to the upper troposphere, and possibly into the stratosphere. Here, we investigate the fate of air that originates within the upper tropospheric anticyclone from the outflow of deep convection, using trajectories driven by ERA-interim reanalysis data. Calculations include isentropic estimates, plus fully three-dimensional results based on kinematic and diabatic transport calculations. Isentropic calculations show that air parcels are typically confined within the anticyclone for 10–20 days, and spread over the tropical belt within a month of their initialization. However, only few parcels (3 % at 360 K, 8 % at 380 K) reach the extratropical stratosphere by isentropic mixing. When considering vertical transport we find that 31 % (48%) of the trajectories reach the stratosphere within 60 days when using vertical velocities or diabatic heating rates to calculate vertical transport, respectively. In both cases, most parcels that reach the stratosphere are transported upward within the anticyclone and enter the stratosphere in the tropics, typically 10–20 days after their initialization at 360 K. This suggests that trace gases, including pollutants, that are transported into the stratosphere via the Asian monsoon system are in a position to enter the tropical pipe and thus be transported into the deep stratosphere. Sensitivity calculations with respect to the initial altitude of the trajectories showed that air needs to be transported to levels of 360 K or above by deep convection to likely (&geqq;50 %) reach the stratosphere through transport by the large-scale circulation.

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Transport pathways from the Asian monsoon anticyclone to the stratosphere

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-2703-2016 ◽

2016 ◽

Vol 16 (4) ◽

pp. 2703-2718 ◽

Cited By ~ 42

Author(s):

Hella Garny ◽

William J. Randel

Keyword(s):

Large Scale ◽

Asian Monsoon ◽

Deep Convection ◽

Three Dimensional ◽

Reanalysis Data ◽

Vertical Transport ◽

Heating Rates ◽

Transport Pathways ◽

Northern Summer ◽

The Tropics

Abstract. Transport pathways of air originating in the upper-tropospheric Asian monsoon anticyclone are investigated based on three-dimensional trajectories. The Asian monsoon anticyclone emerges in response to persistent deep convection over India and southeast Asia in northern summer, and this convection is associated with rapid transport from the surface to the upper troposphere and possibly into the stratosphere. Here, we investigate the fate of air that originates within the upper-tropospheric anticyclone from the outflow of deep convection, using trajectories driven by ERA-interim reanalysis data. Calculations include isentropic estimates, plus fully three-dimensional results based on kinematic and diabatic transport calculations. Isentropic calculations show that air parcels are typically confined within the anticyclone for 10–20 days and spread over the tropical belt within a month of their initialization. However, only few parcels (3 % at 360 K, 8 % at 380 K) reach the extratropical stratosphere by isentropic transport. When considering vertical transport we find that 31 % or 48 % of the trajectories reach the stratosphere within 60 days when using vertical velocities or diabatic heating rates to calculate vertical transport, respectively. In both cases, most parcels that reach the stratosphere are transported upward within the anticyclone and enter the stratosphere in the tropics, typically 10–20 days after their initialization at 360 K. This suggests that trace gases, including pollutants, that are transported into the stratosphere via the Asian monsoon system are in a position to enter the tropical pipe and thus be transported into the deep stratosphere. Sensitivity calculations with respect to the initial altitude of the trajectories showed that air needs to be transported to levels of 360 K or above by deep convection to likely (≧ 50 %) reach the stratosphere through transport by the large-scale circulation.

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Quantitative Assessment of Diurnal Variation of Tropical Convection Simulated by a Global Nonhydrostatic Model without Cumulus Parameterization

Journal of Climate ◽

10.1175/jcli-d-11-00295.1 ◽

2012 ◽

Vol 25 (14) ◽

pp. 5119-5134 ◽

Cited By ~ 23

Author(s):

Akira T. Noda ◽

Kazuyoshi Oouchi ◽

Masaki Satoh ◽

Hirofumi Tomita

Keyword(s):

Diurnal Variation ◽

Deep Convection ◽

Three Dimensional ◽

Cumulus Parameterization ◽

Surface Precipitation ◽

Convective Systems ◽

Nonhydrostatic Model ◽

Precipitation Area ◽

The Tropics ◽

Horizontal Grid

Abstract This study investigated the resolution dependence of diurnal variation in tropical convective systems represented by a global nonhydrostatic model without cumulus parameterization. This paper describes the detailed characteristics of diurnal variation in surface precipitation based on three-dimensional data, with the aim of explicitly clarifying the mechanism that underlies the variation. The study particularly focused on the evolution in the size of the precipitation area for deep convective systems with an analysis of the vertical structure of thermodynamic fields. This analysis compares the results of simulations with horizontal grid sizes of 14 and 7 km (R14 and R7, respectively). Over land, the phase delay of diurnal variations in R7 is about 3 h less than that in R14. R7 produces a pronounced diurnal variation in the size distributions of precipitating area(s), especially for areas with a radius of 0–100 km; this characteristic is not found for R14. Such areas actively evolve between noon and evening, leading to the smooth development of larger-scale precipitating areas having a radius of 100–150 km. The maximum surface precipitation in R7 over land occurs at around 2000 local time throughout the tropics, approximately 2 h prior to the development of nighttime deep convection. Deep convective regimes are important as agents of vertical heat transport in the tropics. The present results suggest that precipitating areas with a radius <100 km make a strong contribution to the total amount of precipitation and to mass transport.

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Three-dimensional assessment of the anterior and inferior loop of the inferior alveolar nerve using computed tomography images in patients with and without mandibular asymmetry

BMC Oral Health ◽

10.1186/s12903-021-01424-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jae-Young Kim ◽

Michael D. Han ◽

Kug Jin Jeon ◽

Jong-Ki Huh ◽

Kwang-Ho Park

Keyword(s):

Computed Tomography ◽

Symmetry Group ◽

Three Dimensional ◽

Inferior Alveolar Nerve ◽

Mental Foramen ◽

3D Analysis ◽

Mandibular Asymmetry ◽

Computed Tomography Images ◽

Significant Difference ◽

Mandibular Body

Abstract Background The purpose of this study was to investigate the differences in configuration and dimensions of the anterior loop of the inferior alveolar nerve (ALIAN) in patients with and without mandibular asymmetry. Method Preoperative computed tomography images of patients who had undergone orthognathic surgery from January 2016 to December 2018 at a single institution were analyzed. Subjects were classified into two groups as “Asymmetry group” and “Symmetry group”. The distance from the most anterior and most inferior points of the ALIAN (IANant and IANinf) to the vertical and horizontal reference planes were measured (dAnt and dInf). The distance from IANant and IANinf to the mental foramen were also calculated (dAnt_MF and dInf_MF). The length of the mandibular body and symphysis area were measured. All measurements were analyzed using 3D analysis software. Results There were 57 total eligible subjects. In the Asymmetry group, dAnt and dAnt_MF on the non-deviated side were significantly longer than the deviated side (p < 0.001). dInf_MF on the non-deviated side was also significantly longer than the deviated side (p = 0.001). Mandibular body length was significantly longer on the non-deviated side (p < 0.001). There was no significant difference in length in the symphysis area (p = 0.623). In the Symmetry group, there was no difference between the left and right sides for all variables. Conclusion In asymmetric patients, there is a difference tendency in the ALIAN between the deviated and non-deviated sides. In patients with mandibular asymmetry, this should be considered during surgery in the anterior mandible.

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Three-dimensional in situ morphometrics of Mycobacterium tuberculosis infection within lesions by optical mesoscopy and novel acid-fast staining

Scientific Reports ◽

10.1038/s41598-020-78640-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Robert J. Francis ◽

Gillian Robb ◽

Lee McCann ◽

Bhagwati Khatri ◽

James Keeble ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Three Dimensional ◽

Large Field ◽

Staining Procedure ◽

3D Analysis ◽

Mycobacterium Tuberculosis Infection ◽

In Vivo Models ◽

Novel Approach

AbstractTuberculosis (TB) preclinical testing relies on in vivo models including the mouse aerosol challenge model. The only method of determining colony morphometrics of TB infection in a tissue in situ is two-dimensional (2D) histopathology. 2D measurements consider heterogeneity within a single observable section but not above and below, which could contain critical information. Here we describe a novel approach, using optical clearing and a novel staining procedure with confocal microscopy and mesoscopy, for three-dimensional (3D) measurement of TB infection within lesions at sub-cellular resolution over a large field of view. We show TB morphometrics can be determined within lesion pathology, and differences in infection with different strains of Mycobacterium tuberculosis. Mesoscopy combined with the novel CUBIC Acid-Fast (CAF) staining procedure enables a quantitative approach to measure TB infection and allows 3D analysis of infection, providing a framework which could be used in the analysis of TB infection in situ.

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Dimensional Accuracy of Dental Models for Three-Unit Prostheses Fabricated by Various 3D Printing Technologies

Materials ◽

10.3390/ma14061550 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1550

Author(s):

Soo-Yeon Yoo ◽

Seong-Kyun Kim ◽

Seong-Joo Heo ◽

Jai-Young Koak ◽

Joung-Gyu Kim

Keyword(s):

Surface Roughness ◽

Three Dimensional ◽

Dimensional Accuracy ◽

3D Analysis ◽

Digital Light Processing ◽

Test Models ◽

Reference File ◽

Significant Difference ◽

Jet Printing ◽

3D Printed

Previous studies on accuracy of three-dimensional (3D) printed model focused on full arch measurements at few points. The aim of this study was to examine the dimensional accuracy of 3D-printed models which were teeth-prepped for three-unit fixed prostheses, especially at margin and proximal contact areas. The prepped dental model was scanned with a desktop scanner. Using this reference file, test models were fabricated by digital light processing (DLP), Multi-Jet printing (MJP), and stereo-lithography apparatus (SLA) techniques. We calculated the accuracy (trueness and precision) of 3D-printed models on 3D planes, and deviations of each measured points at buccolingual and mesiodistal planes. We also analyzed the surface roughness of resin printed models. For overall 3D analysis, MJP showed significantly higher accuracy (trueness) than DLP and SLA techniques; however, there was not any statistically significant difference on precision. For deviations on margins of molar tooth and distance to proximal contact, MJP showed significantly accurate results; however, for a premolar tooth, there was no significant difference between the groups. 3D color maps of printed models showed contraction buccolingually, and surface roughness of the models fabricated by MJP technique was observed as the lowest. The accuracy of the 3D-printed resin models by DLP, MJP, and SLA techniques showed a clinically acceptable range to use as a working model for manufacturing dental prostheses

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Properties of Steady Geostrophic Turbulence with Isopycnal Outcropping

Journal of Physical Oceanography ◽

10.1175/jpo-d-11-09.1 ◽

2012 ◽

Vol 42 (1) ◽

pp. 18-38 ◽

Cited By ~ 25

Author(s):

G. Roullet ◽

J. C. McWilliams ◽

X. Capet ◽

M. J. Molemaker

Keyword(s):

High Resolution ◽

Large Scale ◽

Mechanical Energy ◽

Baroclinic Instability ◽

Three Dimensional ◽

Primary Source ◽

Eddy Diffusivity ◽

Energy Cycle ◽

Geostrophic Turbulence ◽

Pv Gradient

Abstract High-resolution simulations of β-channel, zonal-jet, baroclinic turbulence with a three-dimensional quasigeostrophic (QG) model including surface potential vorticity (PV) are analyzed with emphasis on the competing role of interior and surface PV (associated with isopycnal outcropping). Two distinct regimes are considered: a Phillips case, where the PV gradient changes sign twice in the interior, and a Charney case, where the PV gradient changes sign in the interior and at the surface. The Phillips case is typical of the simplified turbulence test beds that have been widely used to investigate the effect of ocean eddies on ocean tracer distribution and fluxes. The Charney case shares many similarities with recent high-resolution primitive equation simulations. The main difference between the two regimes is indeed an energization of submesoscale turbulence near the surface. The energy cycle is analyzed in the (k, z) plane, where k is the horizontal wavenumber. In the two regimes, the large-scale buoyancy forcing is the primary source of mechanical energy. It sustains an energy cycle in which baroclinic instability converts more available potential energy (APE) to kinetic energy (KE) than the APE directly injected by the forcing. This is due to a conversion of KE to APE at the scale of arrest. All the KE is dissipated at the bottom at large scales, in the limit of infinite resolution and despite the submesoscales energizing in the Charney case. The eddy PV flux is largest at the scale of arrest in both cases. The eddy diffusivity is very smooth but highly nonuniform. The eddy-induced circulation acts to flatten the mean isopycnals in both cases.

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