A5079112878- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Geophysics and Gravity Measurements
- Radio Astronomy Observations and Technology
- Spectroscopy and Laser Applications
- Solar and Space Plasma Dynamics
- GNSS positioning and interference
- Spacecraft Design and Technology
- Soil Moisture and Remote Sensing
- Atmospheric aerosols and clouds
- Precipitation Measurement and Analysis
- Meteorological Phenomena and Simulations
- Antenna Design and Optimization
- Superconducting and THz Device Technology
- Cosmology and Gravitation Theories
- Geography Education and Pedagogy
- Satellite Communication Systems
- Gas Sensing Nanomaterials and Sensors
- Astrophysics and Cosmic Phenomena
- Climate variability and models
- Inertial Sensor and Navigation
- Ocean Waves and Remote Sensing
- Calibration and Measurement Techniques
Chalmers University of Technology
2009-2021
Abstract. In this study, we present middle atmospheric water vapor (H2O) and ozone (O3) measurements obtained by ground-based microwave radiometers at three European locations in Bern (47° N), Onsala (57° N) Sodankylä (67° during Northern winter 2009/2010. January 2010, a major sudden stratospheric warming (SSW) occurred the Hemisphere whose signatures are evident observations of H2O O3. The observed anomalies O3 mostly explained relative location polar vortex with respect to measurement...
Abstract. Inter-hemispheric coupling between the polar summer mesosphere and planetary-wave activity in extra-tropical winter stratosphere has recently been inferred using Polar Mesospheric Cloud (PMC) properties as a proxy for mesospheric temperature (Karlsson et al., 2007). Here we confirm these results ten-year time series of July temperatures near 60° N derived from hydroxyl (OH) nightglow. In addition, show that time-lagged correlation ECMWF stratospheric displays strong Quasi-Biennial...
We present a detailed intercomparison of five ground‐based 22 GHz microwave radiometers for stratospheric and mesospheric water vapor. Four these instruments are members the Network Detection Atmospheric Composition Change (NDACC). The global measurements middle atmospheric vapor Microwave Limb Sounder (MLS) onboard Aura satellite serve as reference allow systems that located between 45°S 57°N. retrievals profiles from radiation have been made consistent to large extent: required temperature...
The Sub‐Millimetre Radiometer (SMR) aboard the Odin satellite has been measuring vertical profiles of atmospheric trace gases since August 2001. We present inversion methodology developed for CO measurements and first retrieval results. can be retrieved from a single scan measurement throughout middle atmosphere, with typical resolution ∼3 km relative error ∼10% to ∼25%. Retrieval results are evaluated through comparison data Whole Atmosphere Community Climate Model (WACCM) observations...
Abstract. Measurements of mesospheric carbon monoxide, CO, provide important information about the dynamics in mesosphere region since CO has a long lifetime at these altitudes. Ground-based measurements made Onsala Space Observatory, OSO, (57° N, 12° E) are presented. The dataset covers period 2002–2008 and is hence uniquely for ground-based observations. simple stable 115 GHz frequency-switched radiometer, calibration method, retrieval procedure error characterization described. A...
In this report daily ground‐based measurements of vertical profiles CO and H 2 O from 2002 are used to trace the movement air caused by seasonally varying mean meridional circulation. spring (days 100–130) estimated ascending velocity is found vary with time altitude about between 250 m/day at 65 km on day 100 a maximum ∼450 85–90 130. late summer fall descending goes 0 (when downwelling starts) ∼250 75 280. The mesospheric adiabatic temperature changes compared mesopause as radiance Meinel...
The longest continuous series of ground‐based measurements mesospheric CO is presented. data cover the period September 2000 to 2002. Sporadic from 1988 and 1989 are also reported. results show a large accumulation in winter mesosphere, which consistent with generally accepted ideas about seasonally‐varying mean meridional circulation. Comparison observations simulations by Whole Atmosphere Community Climate Model (WACCM) indicate that model can reproduce observed seasonal cycle as well much...
Abstract. As part of the second SPARC (Stratosphere–troposphere Processes And their Role in Climate) water vapor assessment (WAVAS-II), we present measurements taken from or coincident with seven sites which ground-based microwave instruments measure middle atmosphere. Six are Network for Detection Atmospheric Composition Change (NDACC) and provide datasets that can be used drift trend assessment. We compare these satellite have provided retrievals lower mesosphere over extended periods...
Abstract. We have studied linear horizontal gradients in the atmospheric propagation delay above ground-based stations receiving signals from Global Positioning System (GPS). Gradients were estimated 11 years of observations five sites Sweden. Comparing these with corresponding ones European Centre for Medium-Range Weather Forecasts (ECMWF) analyses shows that GPS detect effects over different timescales caused by hydrostatic and wet components. The two equipped microwave-absorbing material...
Abstract. During the last decades, ground-based microwave radiometry has matured into an established remote sensing technique for measuring vertical profiles of a number gases in stratosphere and mesosphere. Microwave is only that can provide upper mesosphere both day night, even during cloudy conditions. Except instruments placed at high-altitude sites, or sites with dry atmospheric conditions, molecules significant emission lines below 150 GHz, such as CO, H2O, O3, be observed. Vertical...
Abstract. The Sub-Millimetre Radiometer (SMR) on board the Odin satellite performs limb sounding measurements of middle atmosphere to detect molecular emission from different species. Carbon monoxide (CO) is an important tracer atmospheric dynamics at these altitudes, due its long photochemical lifetime and high vertical concentration gradient. In this study, we have successfully recovered over 18 years SMR observations, providing only dataset date being so extended in time stretching out...
The hydroxyl (OH) rotational temperature and band emission rate have been derived using year‐round, ground‐based measurements of the infrared OH nightglow from Sweden 1991 to 2002. Recent work has suggested that, during winter, all scales dynamical variations radiance arise vertical motions, implying that effective source concentrations atomic oxygen are constant. present data show correlations between both winter summer consistent with those observed in previous work. However, transition...
Abstract The accuracy of geodetic Very Long Baseline Interferometry (VLBI) is affected by water vapour in the atmosphere terms variations signal propagation delay at different stations. This “wet” may be estimated directly from VLBI data, as well independent instruments, such collocated microwave radiometers. Rather than having stand-alone radiometers we have, through simulations, evaluated possibility to use radiometric data receiver VGOS telescopes Onsala Space Observatory. advantage that...
Abstract. We assess the quality of estimated linear horizontal gradients in atmospheric propagation delay above ground-based stations receiving signals from Global Positioning System (GPS). Gradients are 11 years observations five sites Sweden. Comparing these with corresponding ones European Centre for Medium-Range Weather Forecasts (ECMWF) analyses show that GPS confirm known seasonal effects both hydrostatic and wet components. The two equipped microwave absorbing material below antenna...
Abstract. During the last decades, ground-based microwave radiometry has matured to an established remote sensing technique for measuring vertical profiles of a number gases in stratosphere and mesosphere. Microwave is only that can provide upper mesosphere both day night, even during cloudy conditions. Except instruments placed at high altitude sites, or sites with dry atmospheric conditions, molecules significant emission lines below 150 GHz, such as CO, H2O O3 be observed. Vertical these...
Abstract. A major sudden stratospheric warming (SSW) occurred in the Northern Hemisphere January 2010. The started on 26 2010, was most pronounced by end of and accompanied a polar vortex shift towards Europe. After warming, split into two weaker vortices. zonal mean temperature upper stratosphere (35–45 km) increased approximately 25 K few days, while there decrease lower mesosphere. Local maxima were around 325 minima 175 155 mesosphere, respectively. In this study, we present middle...
Abstract. Measurements of mesospheric carbon monoxide, CO, provide important information about the dynamics in mesosphere region since CO has a long lifetime at these altitudes. Ground-based measurements made Onsala Space Observatory, OSO, (57° N, 12° E) are presented. The dataset covers period 2002–2008 and is hence uniquely long. simple stable 115 GHz frequency-switched radiometer, calibration method, retrieval procedure error characterization described. A comparison between our co-located...