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To improve our knowledge of the coupling of atmospheric circulation, composition and regional climate, and to provide the urgently needed observations of long-term changes in the middle atmosphere, the Changing-Atmosphere Infra-Red Tomography Explorer (CAIRT) is one of four mission concepts down-selected by the European Space Agency (ESA) for competitive pre-feasibility studies, vying for implementation as the next Earth Explorer satellite mission. As a Fourier transform infrared limb imager, CAIRT will observe simultaneously from the middle troposphere to the lower thermosphere at high spectral resolution and with unprecedented horizontal and vertical resolution (with a goal of 50×50×1 km globally). With this, CAIRT will provide new and critical information on (a) atmospheric gravity waves, circulation and mixing, (b) coupling with the upper atmosphere, solar variability and space weather and, (c) aerosols and pollutants in the upper troposphere and lower stratosphere. In this presentation we will give an overview of CAIRT’s science goals and the expected mission performance, based on latest results from early mission definition studies., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Polar winter descent of reactive nitrogen (NOy) produced by energetic particle precipitation (EPP) in the mesosphere and lower thermosphere affects polar stratospheric ozone by catalytic reactions. This, in turn, may have implications for regional climate via radiative and dynamical feedbacks. NOy observations taken by the MIPAS/Envisat instrument during 2002--2012 have provided observational constraints on the solar-activity modulated variability of stratospheric EPP-NOy amounts. These constraints have allowed to formulate a chemical upper boundary condition for climate models in the context of solar forcing recommendations for CMIP6. Recently, a reprocessed MIPAS version 8 dataset has been released. Compared to the previous version, we assess what impact the changes in this new data version have on the EPP-NOy quantification, and on the formulation of chemical upper boundary conditions for climate models.The Earth Explorer 11 candidate Changing Atmosphere Infra-Red Tomography (CAIRT) will observe the altitude region from about 5 km to 115 km with an across-track resolution of 30 to 50 km within a 500 km wide field of view. This instrument will provide NOy and dynamical tracer observations from the upper troposphere to the lower thermosphere with unprecedented spatial resolution. Given that neither MIPAS nor any of the current instruments observes the lower thermosphere at this spatial resolution, we will assess the potential of this mission to advance our understanding of the EPP-climate link in the future., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The final level-1b version of MIPAS spectral data, version 8, is the basis of the improved level-2 IMK/IAA research data product that covers all observations modes (NOM, UTLS, MA, UA and NLC) and consists of: temperature, O3, H2O, CH4, N2O, CO, HNO3, NO2, NO, HNO4, BrONO2, N2O5, PAN, ClONO2, ClO, HOCl, CCl4, CH3Cl, COCl2, COF2, COClF, CFC-11, CFC-12, HCFC-22, CFC-113, CF4, C2H6, C2H2, HCN, HCOOH, H2CO, CH3OH, CH3COOH, acetone, HDO, H2O2, O3P, heavy ozone isotopologues, 15N isotopologues of HNO3, N2O, and NO2, SO2, OCS, SF6, NH3, sulphate aerosol, ammonium nitrate aerosol, PSCs, PMCs, and CO2 (above 65 km).Improvements with respect to previous versions will be discussed. The data come on a constant fine vertical altitude grid and contain pressure, temperature, trace gas volume mixing ratios, vertical resolution and the diagonal of the averaging kernel matrix. An elaborate error estimation for each single profile, compliant with the SPARC TUNER initiative and described in von Clarmann et al. (2022, doi: 10.5194/amt-15-6991-2022), is provided. In addition, as an easy-to-use data product, the abundances of most of the retrieved trace gases are also provided on a coarser vertical grid (constant over location and time for an individual trace gas) for which the averaging kernel matrix transforms to a unity matrix. This presentation allows for a fast and direct comparison to model simulations. We present examples for temperature and several trace species, demonstrate the improvements against earlier data versions, and discuss a number of use cases., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Changing-Atmosphere Infra-Red Tomography Explorer (CAIRT) is one of the four candidates for ESA’s Earth Explorer 11, aimed to study the coupling between atmospheric composition, circulation and climate. By exploiting its imaging capabilities, CAIRT indeed can sound the atmosphere simultaneously from the middle troposphere to the lower thermosphere at 0.2 cm-1 spectral resolution and with horizontal sampling of 50 km along track, 50 km across track and vertical sampling of 1 km. Flying in loose formation with MetOp-SG mission allows to combine spatially resolved limb observations with horizontally resolved nadir measurements of IASI-NG and Sentinel-5 nadir spectrometers to extend limb observations down to the surface. An accurate knowledge of trace gas composition around the tropopause is particularly important to reduce significant uncertainties in projected future warming: changes in the surface air pollution and in the stratosphere-troposphere exchange may significantly affect it. Moreover quantifying the influence of stratospheric transport on near-surface tropospheric composition is important since it conditions attempts to derive emission fluxes from surface observations for important greenhouse gases. We evaluated advantages coming from the exploitation of the synergy between realistic simulations of CAIRT, IASI-NG and Sentinel 5 observations applying the rigorous approach of the two-dimensional complete data fusion. The synergistic products demonstrate a better quality in sounding both the troposphere and the Upper Troposphere - Lower Stratosphere region. Results will be shown for selected case studies involving ozone, methane and other pollutants., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Fragestellung: Der ulnare Handgelenkschmerz ist ein vielfach beklagtes Symptom. Eine häufige Ursache ist hierbei eine Läsion des Triangulären Fibrokartilaginären Komplexes (TFCC). Als Standard der nichtinvasiven Diagnostik gilt die Magnetresonanztomographie (MRT) des Handgelenkes, [zum vollständigen Text gelangen Sie über die oben angegebene URL]

The Arctic winter 2015–2016 was characterized by exceptionally low stratospheric temperatures, favouring the formation of polar stratospheric clouds (PSCs) from mid-December until the end of February down to low stratospheric altitudes. Observations by GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) on HALO (High Altitude and LOng range research aircraft) during the PGS (POLSTRACC–GW-LCYCLE II–SALSA) campaign from December 2015 to March 2016 allow the investigation of the influence of denitrification on the lowermost stratosphere (LMS) with a high spatial resolution. Two-dimensional vertical cross sections of nitric acid (HNO3) along the flight track and tracer–tracer correlations derived from the GLORIA observations document detailed pictures of wide-spread nitrification of the Arctic LMS during the course of an entire winter. GLORIA observations show large-scale structures and local fine structures with enhanced absolute HNO3 volume mixing ratios reaching up to 11 ppbv at altitudes of 13 km in January and nitrified filaments persisting until the middle of March. Narrow coherent structures tilted with altitude of enhanced HNO3, observed in mid-January, are interpreted as regions recently nitrified by sublimating HNO3-containing particles. Overall, extensive nitrification of the LMS between 5.0 and 7.0 ppbv at potential temperature levels between 350 and 380 K is estimated. The GLORIA observations are compared with CLaMS (Chemical Lagrangian Model of the Stratosphere) simulations. The fundamental structures observed by GLORIA are well reproduced, but differences in the fine structures are diagnosed. Further, CLaMS predominantly underestimates the spatial extent of HNO3 maxima derived from the GLORIA observations as well as the overall nitrification of the LMS. Sensitivity simulations with CLaMS including (i) enhanced sedimentation rates in case of ice supersaturation (to resemble ice nucleation on nitric acid trihydrate (NAT)), (ii) a global temperature offset, (iii) modified growth rates (to resemble aspherical particles with larger surfaces) and (iv) temperature fluctuations (to resemble the impact of small-scale mountain waves) slightly improved the agreement with the GLORIA observations of individual flights. However, no parameter could be isolated which resulted in a general improvement for all flights. Still, the sensitivity simulations suggest that details of particle microphysics play a significant role for simulated LMS nitrification in January, while air subsidence, transport and mixing become increasingly important for the simulated HNO3 distributions towards the end of the winter.

Einleitung: Ultraschallkontrastverstärker (CEUS contrast enhanced ultrasound) sind mit dem inerten Gas Schwefelhexafluorid (SF6) durch eine Phospholipidmem-bran stabilisierte Mikrobläschen, die als reines blood-pool-Kontrastmittel die Organvaskularisation und -perfusion darstellen. In der[zum vollständigen Text gelangen Sie über die oben angegebene URL], 61. Jahrestagung der Südwestdeutschen Gesellschaft für Urologie e.V.

The 2015/2016 Arctic winter was one of the coldest stratospheric winters in recent years. A stable vortex formed by early December and the early winter was exceptionally cold. Cold pool temperatures dropped below the nitric acid trihydrate (NAT) existence temperature of about 195 K, thus allowing polar stratospheric clouds (PSCs) to form. The low temperatures in the polar stratosphere persisted until early March, allowing chlorine activation and catalytic ozone destruction. Satellite observations indicate that sedimentation of PSC particles led to denitrification as well as dehydration of stratospheric layers. Model simulations of the 2015/2016 Arctic winter nudged toward European Centre for Medium-Range Weather Forecasts (ECMWF) analysis data were performed with the atmospheric chemistry–climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC) for the Polar Stratosphere in a Changing Climate (POLSTRACC) campaign. POLSTRACC is a High Altitude and Long Range Research Aircraft (HALO) mission aimed at the investigation of the structure, composition and evolution of the Arctic upper troposphere and lower stratosphere (UTLS). The chemical and physical processes involved in Arctic stratospheric ozone depletion, transport and mixing processes in the UTLS at high latitudes, PSCs and cirrus clouds are investigated. In this study, an overview of the chemistry and dynamics of the 2015/2016 Arctic winter as simulated with EMAC is given. Further, chemical–dynamical processes such as denitrification, dehydration and ozone loss during the 2015/2016 Arctic winter are investigated. Comparisons to satellite observations by the Aura Microwave Limb Sounder (Aura/MLS) as well as to airborne measurements with the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) performed aboard HALO during the POLSTRACC campaign show that the EMAC simulations nudged toward ECMWF analysis generally agree well with observations. We derive a maximum polar stratospheric O3 loss of ∼ 2 ppmv or 117 DU in terms of column ozone in mid-March. The stratosphere was denitrified by about 4–8 ppbv HNO3 and dehydrated by about 0.6–1 ppmv H2O from the middle to the end of February. While ozone loss was quite strong, but not as strong as in 2010/2011, denitrification and dehydration were so far the strongest observed in the Arctic stratosphere in at least the past 10 years.