Retrieval of three-dimensional small-scale structures in upper-tropospheric/lower-stratospheric composition as measured by GLORIA

Abstract. The three-dimensional quantification of small-scale processes in the upper troposphere and lower stratosphere is one of the challenges of current atmospheric research and requires the development of new measurement strategies. This work presents the first results from the newly developed Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) obtained during the ESSenCe (ESa Sounder Campaign) and TACTS/ESMVal (TACTS: Transport and composition in the upper troposphere/lowermost stratosphere, ESMVal: Earth System Model Validation) aircraft campaigns. The focus of this work is on the so-called dynamics-mode data characterized by a medium-spectral and a very-high-spatial resolution. The retrieval strategy for the derivation of two- and three-dimensional constituent fields in the upper troposphere and lower stratosphere is presented. Uncertainties of the main retrieval targets (temperature, O3, HNO3, and CFC-12) and their spatial resolution are discussed. During ESSenCe, high-resolution two-dimensional cross-sections have been obtained. Comparisons to collocated remote-sensing and in situ data indicate a good agreement between the data sets. During TACTS/ESMVal, a tomographic flight pattern to sense an intrusion of stratospheric air deep into the troposphere was performed. It was possible to reconstruct this filament at an unprecedented spatial resolution of better than 500 m vertically and 20 × 20 km horizontally.

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Retrieval of three-dimensional small scale structures in upper tropospheric/lower stratospheric composition as measured by GLORIA

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-7-4229-2014 ◽

2014 ◽

Vol 7 (4) ◽

pp. 4229-4274 ◽

Cited By ~ 10

Author(s):

M. Kaufmann ◽

J. Blank ◽

T. Guggenmoser ◽

J. Ungermann ◽

A. Engel ◽

...

Keyword(s):

Spatial Resolution ◽

Cross Sections ◽

Lower Stratosphere ◽

Three Dimensional ◽

Small Scale ◽

Flight Pattern ◽

Upper Troposphere ◽

In Situ Data ◽

Very High Spatial Resolution ◽

First Results

Abstract. The three-dimensional quantification of small scale processes in the upper troposphere and lower stratosphere is one of the challenges of current atmospheric research and requires the development of new measurement strategies. This work presents first results from the newly developed Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) obtained during the ESSenCe and TACTS/ESMVal aircraft campaigns. The focus of this work is on the so-called dynamics mode data characterized by a medium spectral and a very high spatial resolution. The retrieval strategy for the derivation of two- and three-dimensional constituent fields in the upper troposphere and lower stratosphere is presented. Uncertainties of the main retrieval targets (temperature, O3, HNO3 and CFC-12) and their spatial resolution are discussed. During ESSenCe, high resolution two-dimensional cross-sections have been obtained. Comparisons to collocated remote-sensing and in-situ data indicate a good agreement between the data sets. During TACTS/ESMVal a tomographic flight pattern to sense an intrusion of stratospheric air deep into the troposphere has been performed. This filament could be reconstructed with an unprecedented spatial resolution of better than 500 m vertically and 20 km × 20 km horizontally.

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Modeling the transport of very short-lived substances into the tropical upper troposphere and lower stratosphere

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-18511-2009 ◽

2009 ◽

Vol 9 (5) ◽

pp. 18511-18543 ◽

Cited By ~ 2

Author(s):

J. Aschmann ◽

B. M. Sinnhuber ◽

E. L. Atlas ◽

S. M. Schauffler

Keyword(s):

Large Scale ◽

Lower Stratosphere ◽

Transport Model ◽

Three Dimensional ◽

Chemical Transport Model ◽

Heating Rates ◽

Model Calculations ◽

Upper Troposphere ◽

Mass Fluxes ◽

Tropical Upper Troposphere

Abstract. The transport of very short-lived substances into the tropical upper troposphere and lower stratosphere is investigated by a three-dimensional chemical transport model using archived convective updraft mass fluxes (or detrainment rates) from the European Centre for Medium-Range Weather Forecast's ERA-Interim reanalysis. Large-scale vertical velocities are calculated from diabatic heating rates. With this approach we explicitly model the large scale subsidence in the tropical troposphere with convection taking place in fast and isolated updraft events. The model calculations agree generally well with observations of bromoform and methyl iodide from aircraft campaigns and with ozone and water vapor from sonde and satellite observations. Using a simplified treatment of dehydration and bromine product gas washout we give a range of 1.6 to 3 ppt for the contribution of bromoform to stratospheric bromine, assuming a uniform source in the boundary layer of 1 ppt. We show that the most effective region for VSLS transport into the stratosphere is the West Pacific, accounting for about 55% of the bromine from bromoform transported into the stratosphere under the supposition of a uniformly distributed source.

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Precipitation Atlas for Germany (GePrA)

Atmosphere ◽

10.3390/atmos10120737 ◽

2019 ◽

Vol 10 (12) ◽

pp. 737

Author(s):

Christopher Jung ◽

Dirk Schindler

Keyword(s):

Spatial Resolution ◽

Large Scale ◽

High Spatial Resolution ◽

Spline Interpolation ◽

Absolute Error ◽

Coefficient Of Determination ◽

Small Scale ◽

Monthly Precipitation ◽

New Approach ◽

Very High Spatial Resolution

A new approach for modeling daily precipitation (RR) at very high spatial resolution (25 m × 25 m) was introduced. It was used to develop the Precipitation Atlas for Germany (GePrA). GePrA is based on 2357 RR time series measured in the period 1981–2018. It provides monthly percentiles (p) of the large-scale RR patterns which were mapped by a thin plate spline interpolation (TPS). A least-squares boosting (LSBoost) approach and orographic predictor variables (PV) were applied to integrate the small-scale precipitation variability in GePrA. Then, a Weibull distribution (Wei) was fitted to RRp. It was found that the mean monthly sum of RR ( R R ¯ s u m ) is highest in July (84 mm) and lowest in April (49 mm). A great dependency of RR on the elevation (ε) was found and quantified. Model validation at 425 stations showed a mean coefficient of determination (R2) of 0.80 and a mean absolute error (MAE) of less than 10 mm in all months. The high spatial resolution, including the effects of the local orography, make GePrA a valuable tool for various applications. Since GePrA does not only describe R R ¯ s u m , but also the entire monthly precipitation distributions, the results of this study enable the seasonal differentiation between dry and wet period at small scales.

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Retrieval of water vapor vertical distributions in the upper troposphere and the lower stratosphere from SCIAMACHY limb measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-4-933-2011 ◽

2011 ◽

Vol 4 (5) ◽

pp. 933-954 ◽

Cited By ~ 25

Author(s):

A. Rozanov ◽

K. Weigel ◽

H. Bovensmann ◽

S. Dhomse ◽

K.-U. Eichmann ◽

...

Keyword(s):

Water Vapor ◽

Solar Radiation ◽

Lower Stratosphere ◽

Water Vapor Content ◽

Retrieval Algorithm ◽

Altitude Range ◽

Upper Troposphere ◽

Vertical Distributions ◽

First Results ◽

Scanning Imaging

Abstract. This study describes the retrieval of water vapor vertical distributions in the upper troposphere and lower stratosphere (UTLS) altitude range from space-borne observations of the scattered solar light made in limb viewing geometry. First results using measurements from SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY) aboard ENVISAT (Environmental Satellite) are presented here. In previous publications, the retrieval of water vapor vertical distributions has been achieved exploiting either the emitted radiance leaving the atmosphere or the transmitted solar radiation. In this study, the scattered solar radiation is used as a new source of information on the water vapor content in the UTLS region. A recently developed retrieval algorithm utilizes the differential absorption structure of the water vapor in 1353–1410 nm spectral range and yields the water vapor content in the 11–25 km altitude range. In this study, the retrieval algorithm is successfully applied to SCIAMACHY limb measurements and the resulting water vapor profiles are compared to in situ balloon-borne observations. The results from both satellite and balloon-borne instruments are found to agree typically within 10 %.

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Trajectory matching of ozonesondes and MOZAIC measurements in the UTLS – Part 1: Method description and application at Payerne, Switzerland

Atmospheric Measurement Techniques ◽

10.5194/amt-6-3393-2013 ◽

2013 ◽

Vol 6 (12) ◽

pp. 3393-3406 ◽

Cited By ~ 7

Author(s):

J. Staufer ◽

J. Staehelin ◽

R. Stübi ◽

T. Peter ◽

F. Tummon ◽

...

Keyword(s):

Total Ozone ◽

Lower Stratosphere ◽

Three Dimensional ◽

Wind Fields ◽

Upper Troposphere ◽

Match Technique ◽

Trajectory Matching ◽

Mean Differences ◽

Concentration Cells ◽

Vertical Gradients

Abstract. With the aim of improving ozonesonde observations in the upper troposphere/lower stratosphere (UTLS), we use three-dimensional forward and backward trajectories, driven by ERA-Interim wind fields to match and compare ozonesonde measurements at Payerne (Switzerland) with observations from the MOZAIC aircraft program from 1994–2009. The uncertainties associated with the sonde–MOZAIC match technique were assessed using "self-matches", i.e. matches of instruments of the same type, such as MOZAIC–MOZAIC. Despite strong vertical gradients of ozone at the tropopause, which render the match approach difficult, the method provides excellent results, showing mean differences between different MOZAIC aircraft of ±2% (typically with a few hours between the up- and downstream match points). Matches between MOZAIC aircraft and Payerne ozonesondes show an agreement of ±5% for sondes equipped with electrochemical concentration cells (ECC) and between < 5% (not scaled to total ozone) and < 10% (scaled) for the Brewer–Mast (BM) sondes after 1998. Prior to 1998, BM sondes show an offset of around 20% (scaled). No break can be identified through the change from the BM to ECC sonde types in September 2002. A comparison of BM sondes with ozone measurements from the NOXAR B747 project for the period 1995–1996 show a smaller offset of around 15% (scaled), which may indicate a small drift in the MOZAIC calibration.

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Assimilation of TES CO into a global CTM: first results

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-6-11727-2006 ◽

2006 ◽

Vol 6 (6) ◽

pp. 11727-11743 ◽

Cited By ~ 2

Author(s):

N. A. D. Richards ◽

Q. Li ◽

K. W. Bowman ◽

J. R. Worden ◽

S. S. Kulawik ◽

...

Keyword(s):

Transport Model ◽

Model Simulation ◽

Three Dimensional ◽

Model Bias ◽

Upper Troposphere ◽

First Results ◽

Assimilation Scheme ◽

Co Observations ◽

Good Agreement

Abstract. We present results from the first assimilation of carbon monoxide (CO) observations from the Tropospheric Emission Spectrometer (TES) into a global three-dimensional (3-D) chemistry and transport model (CTM). A sequential sub-optimal Kalman filter assimilation scheme (Khattatov et al., 2000) was applied to assimilate TES CO profiles during November 2004 into the GEOS-Chem global 3-D CTM. The assimilation results were compared with MOPITT and MOZAIC observations. The assimilation significantly improves model simulation of CO in the middle to upper troposphere, where the MOPITT versus model bias was reduced by up to two-thirds. Assimilation results show higher levels of CO in the southern tropics, consistent with MOPITT observations. We find good agreement between the TES assimilated model estimates of CO and in situ measurements from the MOZAIC program, which shows a negative bias of up to 10 ppbv in middle and upper tropospheric TES CO. The results demonstrate how assimilation can be used for non-coincident validation of TES CO profile retrievals.

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Air mass exchange across the polar vortex edge during a simulated major stratospheric warming

Annales Geophysicae ◽

10.1007/s00585-995-0745-0 ◽

1995 ◽

Vol 13 (7) ◽

pp. 745-756 ◽

Cited By ~ 1

Author(s):

G. Günther ◽

M. Dameris

Keyword(s):

Cross Sections ◽

Middle Atmosphere ◽

Model Simulation ◽

Mechanistic Model ◽

Three Dimensional ◽

Polar Vortex ◽

Small Scale ◽

Stratospheric Warming ◽

Air Masses ◽

Physical And Chemical

Abstract. The dynamics of the polar vortex in winter and spring play an important role in explaining observed low ozone values. A quantification of physical and chemical processes is necessary to obtain information about natural and anthropogenic causes of fluctuations of ozone. This paper aims to contribute to answering the question of how permeable the polar vortex is. The transport into and out of the vortex ("degree of isolation") remains the subject of considerable debate. Based on the results of a three-dimensional mechanistic model of the middle atmosphere, the possibility of exchange of air masses across the polar vortex edge is investigated. Additionally the horizontal and vertical structure of the polar vortex is examined. The model simulation used for this study is related to the major stratospheric warming observed in February 1989. The model results show fair agreement with observed features of the major warming of 1989. Complex structures of the simulated polar vortex are illustrated by horizontal and vertical cross sections of potential vorticity and inert tracer. A three-dimensional view of the polar vortex enables a description of the vortex as a whole. During the simulation two vortices and an anticyclone, grouped together in a very stable tripolar structure, and a weaker, more amorphous anticyclone are formed. This leads to the generation of small-scale features. The results also indicate that the permeability of the vortex edges is low because the interior of the vortices remain isolated during the simulation.

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3-D high‐resolution reflection seismic imaging of unconsolidated glacial and glaciolacustrine sediments: processing and interpretation

Geophysics ◽

10.1190/1.1444709 ◽

2000 ◽

Vol 65 (1) ◽

pp. 18-34 ◽

Cited By ~ 29

Author(s):

Frank Büker ◽

Alan G. Green ◽

Heinrich Horstmeyer

Keyword(s):

High Resolution ◽

Cross Sections ◽

Guided Waves ◽

Three Dimensional ◽

High Amplitude ◽

Seismic Facies ◽

Small Scale ◽

Shallow Subsurface ◽

Reflection Seismic ◽

Reflecting Boundaries

Shallow 3-D seismic reflection techniques have been used to map glacial deposits in a Swiss mountain valley. A dense distribution of source and receiver positions resulted in a small subsurface sampling of 1.5 m × 1.5 m and a high fold of >40. Common processing operations that included pseudotrue amplitude scaling, deconvolution, and band‐pass filtering successfully enhanced shallow reflections relative to source‐generated noise. Careful top muting helped avoid erroneous stacking of direct and guided waves. Azimuth‐dependent velocity analyses proved to be unnecessary. Three‐dimensional (3-D) migration of the stacked data yielded the final high‐resolution images of the shallow subsurface (15–170 m). Because most reflections and diffractions were migrated to their correct subsurface locations, confident interpretations of 3-D structures were possible. Time slices and cross‐sections along arbitrary directions proved to be powerful analysis tools. Even small‐scale features (<20 m wide), such as subglacial channels and troughs, could be mapped. Five major lithologic units separated by four principal reflecting boundaries were distinguished on the basis of their characteristic seismic facies. The principal reflecting boundaries were semiautomatically tracked through the 3-D data volume. Borehole information allowed the uppermost boundary at 15–27 m to be identified as the top of a 68–80-m-thick sequence of basal and reworked tills characterized by high‐amplitude discontinuous to quasi‐continuous reflections. Low reflectivity of seismic units above and below the till units was associated with finely layered or massive glaciolacustrine clay/silt deposited during and after two principal phases of glaciation (Würm at 28 000 to 10 000 and Riss at 200 000 to 100 000 years before the present). Top of Tertiary Molasse basement was delineated by prominent east‐dipping reflections at variable depths of 85–170 m.

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Trajectory matching of ozonesondes and MOZAIC measurements in the UTLS – Part 1: Method description and application at Payerne, Switzerland

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-7063-2013 ◽

2013 ◽

Vol 6 (4) ◽

pp. 7063-7098 ◽

Cited By ~ 1

Author(s):

J. Staufer ◽

J. Staehelin ◽

R. Stübi ◽

T. Peter ◽

F. Tummon ◽

...

Keyword(s):

Total Ozone ◽

Lower Stratosphere ◽

Three Dimensional ◽

Wind Fields ◽

Upper Troposphere ◽

Match Technique ◽

Trajectory Matching ◽

Mean Differences ◽

Vertical Ozone ◽

Concentration Cells

Abstract. With the aim of improving ozonesonde observations in the upper troposphere/lower stratosphere (UTLS), we use three-dimensional forward and backward trajectories, driven by ERA-Interim wind fields to match and compare ozonesonde measurements at Payerne (Switzerland) with observations from the MOZAIC aircraft program from 1994–2009. The uncertainties associated with the sonde–MOZAIC match technique were assessed using "self-matches", i.e. matches of instruments of the same type, such as MOZAIC–MOZAIC. Despite strong vertical ozone gradients of ozone at the tropopause, which render the match approach difficult, the method provides excellent results, showing mean differences between different MOZAIC aircraft of ±2% (typically with a few hours between the up- and downstream match points). Matches between MOZAIC aircraft and Payerne ozonesondes show an agreement of ±5% for sondes equipped with electrochemical concentration cells (ECC) and between <5% (not scaled to total ozone) and <10% (scaled) for the Brewer–Mast (BM) sondes after 1998. Prior to 1998, BM sondes show an offset of around 20% (scaled). No break can be identified through the change from the BM to ECC sonde types in September 2002. A comparison of BM sondes with ozone measurements from the NOXAR B747 project for the period 1995–1996 show a smaller offset of around 15% (scaled), which may indicate a small drift in the MOZAIC calibration.

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