Artículos de revistas: "Balloon observations"

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Maruca, Bennett A., Raffaele Marino, David Sundkvist, Niharika H. Godbole, Stephane Constantin, Vincenzo Carbone y Herb Zimmerman. "Overview of and first observations from the TILDAE High-Altitude Balloon Mission". Atmospheric Measurement Techniques 10, n.º 4 (26 de abril de 2017): 1595–607. http://dx.doi.org/10.5194/amt-10-1595-2017.

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Abstract. Though the presence of intermittent turbulence in the stratosphere has been well established, much remains unknown about it. In situ observations of this phenomenon, which have provided the greatest details of it, have mostly been achieved via sounding balloons (i.e., small balloons which burst at peak altitude) carrying constant-temperature hot-wire anemometers (CTAs). The Turbulence and Intermittency Long-Duration Atmospheric Experiment (TILDAE) was developed to test a new paradigm for stratospheric observations. Rather than flying on a sounding balloon, TILDAE was incorporated as an add-on experiment to the payload of a NASA long-duration balloon mission that launched in January 2016 from McMurdo Station, Antarctica. Furthermore, TILDAE's key instrument was a sonic anemometer, which (relative to a CTA) provides better-calibrated measurements of wind velocity and a more robust separation of velocity components. During the balloon's ascent, TILDAE's sonic anemometer provided atmospheric measurements up to an altitude of about 18 km, beyond which the ambient air pressure was too low for the instrument to function properly. Efforts are currently underway to scientifically analyze these observations of small-scale fluctuations in the troposphere, tropopause, and stratosphere and to develop strategies for increasing the maximum operating altitude of the sonic anemometer.

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Dorf, M., H. Bösch, A. Butz, C. Camy-Peyret, M. P. Chipperfield, A. Engel, F. Goutail et al. "Balloon-borne stratospheric BrO measurements: comparison with Envisat/SCIAMACHY BrO limb profiles". Atmospheric Chemistry and Physics Discussions 5, n.º 6 (19 de diciembre de 2005): 13011–52. http://dx.doi.org/10.5194/acpd-5-13011-2005.

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Abstract. For the first time, results of all four existing stratospheric BrO profiling instruments, are presented and compared with reference to the SLIMCAT 3-dimensional chemical transport model (3-D CTM). Model calculations are used to infer a BrO profile validation set, measured by 3 different balloon sensors, for the new Envisat/SCIAMACHY (ENVIronment SATellite/SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) satellite instrument. The balloon observations include (a) balloon-borne in situ resonance fluorescence detection of BrO, (b) balloon-borne solar occultation DOAS measurements (Differential Optical Absorption Spectroscopy) of BrO in the UV, and (c) BrO profiling from the solar occultation SAOZ (Systeme d'Analyse par Observation Zenithale) balloon instrument. Since stratospheric BrO is subject to considerable diurnal variation and none of the measurements are performed close enough in time and space for a direct comparison, all balloon observations are considered with reference to outputs from the 3-D CTM. The referencing is performed by forward and backward air mass trajectory calculations to match the balloon with the satellite observations. The diurnal variation of BrO is considered by 1-D photochemical model calculation along the trajectories. The 1-D photochemical model is initialised with output data of the 3-D model with additional constraints on the vertical transport, the total amount and photochemistry of stratospheric bromine as given by the various balloon observations. Total [Bry]=(20.1±2.8)pptv obtained from DOAS BrO observations at mid-latitudes in 2003, serves as an upper limit of the comparison. Most of the balloon observations agree with the photochemical model predictions within their given error estimates. First retrieval exercises of BrO limb profiling from the SCIAMACHY satellite instrument agree to <±50% with the photochemically-corrected balloon observations, and tend to show less agreement below 20 km.

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Dorf, M., H. Bösch, A. Butz, C. Camy-Peyret, M. P. Chipperfield, A. Engel, F. Goutail et al. "Balloon-borne stratospheric BrO measurements: comparison with Envisat/SCIAMACHY BrO limb profiles". Atmospheric Chemistry and Physics 6, n.º 9 (29 de junio de 2006): 2483–501. http://dx.doi.org/10.5194/acp-6-2483-2006.

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Abstract. For the first time, results of four stratospheric BrO profiling instruments, are presented and compared with reference to the SLIMCAT 3-dimensional chemical transport model (3-D CTM). Model calculations are used to infer a BrO profile validation set, measured by 3 different balloon sensors, for the new Envisat/SCIAMACHY (ENVIronment SATellite/SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) satellite instrument. The balloon observations include (a) balloon-borne in situ resonance fluorescence detection of BrO (Triple), (b) balloon-borne solar occultation DOAS measurements (Differential Optical Absorption Spectroscopy) of BrO in the UV, and (c) BrO profiling from the solar occultation SAOZ (Systeme d'Analyse par Observation Zenithale) balloon instrument. Since stratospheric BrO is subject to considerable diurnal variation and none of the measurements are performed close enough in time and space for a direct comparison, all balloon observations are considered with reference to outputs from the 3-D CTM. The referencing is performed by forward and backward air mass trajectory calculations to match the balloon with the satellite observations. The diurnal variation of BrO is considered by 1-D photochemical model calculation along the trajectories. The 1-D photochemical model is initialised with output data of the 3-D model with additional constraints on the vertical transport, the total amount and photochemistry of stratospheric bromine as given by the various balloon observations. Total [Bry]=(20.1±2.5) pptv obtained from DOAS BrO observations at mid-latitudes in 2003, serves as an upper limit of the comparison. Most of the balloon observations agree with the photochemical model predictions within their given error estimates. First retrieval exercises of BrO limb profiling from the SCIAMACHY satellite instrument on average agree to around 20% with the photochemically-corrected balloon observations of the remote sensing instruments (SAOZ and DOAS). An exception is the in situ Triple profile, in which the balloon and satellite data mostly does not agree within the given errors. In general, the satellite measurements show systematically higher values below 25 km than the balloon data and a change in profile shape above about 25 km.

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4

Davenhall, Clive. "Dr Katterfelto and the Prehistory of Astronomical Ballooning1". Culture and Cosmos 18, n.º 1 (junio de 2014): 45–53. http://dx.doi.org/10.46472/cc.0118.0209.

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Regular telescopic astronomical observations made from balloons began after World War II, though scientific, particularly meteorological, ballooning dates from the mid-nineteenth century. However, astronomical ballooning has a curious prehistory at the dawn of lighter-than-air travel in the 1780s. The self-styled Dr Katterfelto (c.1743?-99) was a German-born travelling showman, lecturer and considerable self-publicist who in 1784-85 claimed to have made important astronomical discoveries from observations made from a balloon. It is unlikely that he made any such observations, or, indeed, any balloon flights. However, the episode throws some light on the world of the itinerant, eighteenth-century astronomical lecturer and the diffusion of contemporary astronomical and scientific knowledge.

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Choi, Yonghan, Jong-Chul Ha y Gyu-Ho Lim. "Investigation of the Effects of Considering Balloon Drift Information on Radiosonde Data Assimilation Using the Four-Dimensional Variational Method". Weather and Forecasting 30, n.º 3 (1 de junio de 2015): 809–26. http://dx.doi.org/10.1175/waf-d-14-00161.1.

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Abstract Effects of balloon drift information (i.e., position and elapsed ascent time of the balloon) on the assimilation of radiosonde observations are investigated by using the Weather Research and Forecasting (WRF) Model and its data assimilation (WRFDA) system. Special radiosonde observations over the Korean Peninsula, which include the exact position and elapsed time of the balloon, are used instead of estimating the balloon drift information. To consider the balloon drift information appropriately, the four-dimensional variational data assimilation (4DVAR) and a high horizontal resolution (6 km) are used. Cycling experiments over the observation period from 20 June to 4 July 2013 are carried out to obtain the statistical robustness of the effects of considering the balloon drift information, and a single-case experiment is also conducted to show further details about the effects. The verification results of cycling experiments, such as root-mean-square errors (RMSEs) for meteorological-variable forecasts verified against the radiosonde observations and threat and bias scores for rainfall forecasts, show the positive impacts of considering the balloon drift information. Results of the single-case experiment also reveal that the simulated rainfall distribution, time series of hourly rainfall, and quantitative precipitation forecast (QPF) skills are improved through the assimilation of radiosonde observations while considering the balloon drift information. Additionally, forecasts of meteorological variables such as horizontal wind components, temperature, and dewpoint temperature are also improved by considering the balloon drift information in the single-case experiment.

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6

Fishman, G. J. "GAMMA-RAY BURSTS: A PERSONAL VIEW". Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 53 (1 de septiembre de 2021): 100–107. http://dx.doi.org/10.22201/ia.14052059p.2021.53.21.

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The first observations in gamma-ray astronomy were made in the late 1960's, primarily by balloon-borne observations. In the early 1970's, gamma-ray bursts were discovered, completely by accident, by satellites looking for man-made nuclear explosions in space. The celestial nature of these events were soon confirmed by other satellites. The first large detector system designed for cosmic gamma-ray bursts observations was the BATSE instrument on the Compton Gamma-Ray Observatory. Some of the details of the instrumentation onboard ballons and satellites and the gamma-ray bursts observational properties they determined are presented.

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MANI, ANNA, K. R. SIVARAMAN y S. P. VENKITESHWARAN. "Evidence of turbulence in the stratosphere". MAUSAM 10, n.º 2 (27 de noviembre de 2021): 179–84. http://dx.doi.org/10.54302/mausam.v10i2.4047.

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Arnold (1954) has observed considerable turbulence in the stratosphere on four different occasions at Belmar, New Jersey, while tracking balloons with a telescope and a radio direction finder. The turbulence was so severe that the radiosonde separated from the balloon, though it was suspended with a cord with a nominal breaking strength of about 70 lbs. During three observations in June 1950, the instrument separated from the balloon at heights ranging from 28 to 32 km, while in the observation in October it separated at 24 km. He has estimated that a descending current of about 11 m. sec-1 could provide the necessary conditions for a free fall of the sonde of about 10 ft which could break the line.

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8

Hertzog, Albert, Philippe Cocquerez, René Guilbon, Jean-Noël Valdivia, Stéphanie Venel, Claude Basdevant, Gillian Boccara et al. "Stratéole/Vorcore—Long-duration, Superpressure Balloons to Study the Antarctic Lower Stratosphere during the 2005 Winter". Journal of Atmospheric and Oceanic Technology 24, n.º 12 (1 de diciembre de 2007): 2048–61. http://dx.doi.org/10.1175/2007jtecha948.1.

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Abstract In September and October 2005, the Stratéole/Vorcore campaign flew 27 superpressure balloons from McMurdo, Antarctica, into the stratospheric polar vortex. Long-duration flights were successfully achieved, 16 of those flights lasting for more than 2 months. Most flights were terminated because they flew out of the authorized flight domain or because of energy shortage in the gondola. The atmospheric pressure (1-Pa precision) was measured every minute during the flights, whereas air temperature observations (0.25-K accuracy) and balloon positions (absolute GPS observations, 10-m accuracy) were obtained every 15 min. Fifteen-minute-averaged horizontal velocities of the wind were deduced from the successive balloon positions with a corresponding accuracy ≲0.1 m s−1. The collected dataset (more than 150 000 independent observations) provides a thorough high-resolution sampling of the polar lower stratosphere in the Southern Hemisphere from its wintertime state up to the establishment of the summer circulation in December–January. Most of the balloons stayed inside the vortex until its final breakdown, although a few were ejected toward the midlatitudes in November during filamention events associated with an increase in planetary wave activity. The balloons behaved as quasi-Lagrangian tracers during the first part of the campaign (quiescent vortex) and after the vortex breakdown in early December. Large-amplitude mountain gravity waves were detected over the Antarctic Peninsula and caused one flight termination associated with the sudden burst in the balloon superpressure.

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9

Hay, D., G. Ryan, M. Somasundaram, V. Yip y L. Navaratne. "Laparoscopic management of a migrated intragastric balloon causing mechanical small bowel obstruction: a case report and review of the literature". Annals of The Royal College of Surgeons of England 101, n.º 8 (noviembre de 2019): e172-e177. http://dx.doi.org/10.1308/rcsann.2019.0104.

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Intragastric balloons have been used as an invasive non-surgical treatment for obesity for over 30 years. Within the last 37 years, we have found only 27 cases reported in the literature of intestinal obstruction caused by a migrated intragastric balloon. We report the laparoscopic management of such a case and make observations from similar case presentations published in the literature. A 26-year-old woman had an intragastric balloon placed endoscopically for weight control 13 months previously. She presented to the emergency department with a four-day history of intermittent abdominal cramps and vomiting. Contrast enhanced computed tomography confirmed the presence of the intragastric balloon within the small bowel. At laparoscopic retrieval, the deflated intragastric balloon was found impacted in the terminal ileum approximately 15 cm from the ileocaecal valve. The balloon was retrieved by enterotomy and primary closure of the ileum without event. The risk of balloon deflation and subsequent migration increases over time but several published cases demonstrate that this complication can occur within six months of insertion. The initial approach to the treatment of migrated intragastric balloons causing small bowel obstruction should be determined by the location of impaction, severity of obstruction and the available skill set of the attending radiologist, endoscopist and/or surgeon. Balloons causing obstruction in the duodenum are likely amenable to endoscopic retrieval whereas impaction within the jejunum or ileum could be managed by percutaneous needle aspiration (in selected cases), endoscopy (double-balloon enteroscopy), laparoscopy or open surgery.

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Friedrich, Leon S., Adrian J. McDonald, Gregory E. Bodeker, Kathy E. Cooper, Jared Lewis y Alexander J. Paterson. "A comparison of Loon balloon observations and stratospheric reanalysis products". Atmospheric Chemistry and Physics 17, n.º 2 (19 de enero de 2017): 855–66. http://dx.doi.org/10.5194/acp-17-855-2017.

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Abstract. Location information from long-duration super-pressure balloons flying in the Southern Hemisphere lower stratosphere during 2014 as part of X Project Loon are used to assess the quality of a number of different reanalyses including National Centers for Environmental Prediction Climate Forecast System version 2 (NCEP-CFSv2), European Centre for Medium-Range Weather Forecasts (ERA-Interim), NASA Modern Era Retrospective-Analysis for Research and Applications (MERRA), and the recently released MERRA version 2. Balloon GPS location information is used to derive wind speeds which are then compared with values from the reanalyses interpolated to the balloon times and locations. All reanalysis data sets accurately describe the winds, with biases in zonal winds of less than 0.37 m s−1 and meridional biases of less than 0.08 m s−1. The standard deviation on the differences between Loon and reanalyses zonal winds is latitude-dependent, ranging between 2.5 and 3.5 m s−1, increasing equatorward. Comparisons between Loon trajectories and those calculated by applying a trajectory model to reanalysis wind fields show that MERRA-2 wind fields result in the most accurate simulated trajectories with a mean 5-day balloon–reanalysis trajectory separation of 621 km and median separation of 324 km showing significant improvements over MERRA version 1 and slightly outperforming ERA-Interim. The latitudinal structure of the trajectory statistics for all reanalyses displays marginally lower mean separations between 15 and 35° S than between 35 and 55° S, despite standard deviations in the wind differences increasing toward the equator. This is shown to be related to the distance travelled by the balloon playing a role in the separation statistics.

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Rokujo, Hiroki. "GRAINE project: precise gamma-ray observations with balloon-borne emulsion telescope". EPJ Web of Conferences 208 (2019): 14003. http://dx.doi.org/10.1051/epjconf/201920814003.

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Observation of cosmic gamma rays is important in the understanding of high-energy objects or phenomena in the universe. Since 2008, the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope (Fermi-LAT) has surveyed the sub-GeV/GeV gamma-ray sky and achieved high statistics measurements. However, observation at low galactic latitudes remains difficult owing to the lack of angular resolution, and new issues following the operation of Fermi-LAT have arisen. We devised a precise gamma-ray observation project, Gamma-Ray Astro-Imager with Nuclear Emulsion (GRAINE), using balloon-borne emulsion gammaray telescopes to realize high angular resolution, polarization-sensitive, and large-aperture observations in the 10 MeV–100 GeV energy region. Following basic developments on the ground, we performed three balloon-borne experiments with upgraded instruments. In this paper, we present results from the second balloon experiment in 2015, a report on the latest balloon experiment conducted on April 26, 2018, and a recent study on hadronic interactions using proton beams.

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de Bruijn, Evert I. F., Fred C. Bosveld, Siebren de Haan y Bert G. Heusinkveld. "Measuring Low-Altitude Winds with a Hot-Air Balloon and Their Validation with Cabauw Tower Observations". Journal of Atmospheric and Oceanic Technology 37, n.º 2 (febrero de 2020): 263–77. http://dx.doi.org/10.1175/jtech-d-19-0043.1.

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AbstractA field experiment with a hot-air balloon was conducted in the vicinity of the meteorological observatory of Cabauw in The Netherlands. Recreational hot-air balloon flights contain useful wind information in the atmospheric boundary layer (ABL). On a yearly basis between 8000 and 9000 flights are taking place in The Netherlands, mainly during the morning and evening transition. An application (app) for smartphones has been developed to collect location data. We report about a feasibility study of a hot-air balloon experiment where we investigated the accuracy of the smartphone’s Global Navigation Satellite System (GNSS) receiver using an accurate geodetic GNSS receiver as a reference. Further, we study the dynamic response of the hot-air balloon on variations in the wind by measuring the relative wind with a sonic anemometer, which is mounted below the gondola. The GNSS comparison reveals that smartphones equipped with a GNSS chip have in the horizontal plane an absolute position error standard deviation of 5 m, but their relative position error standard deviation is smaller. Therefore, the horizontal speeds, which are based on relative positions and a time step of 1 s, have standard deviations of σu = 0.8 m s−1 and συ = 0.6 m s−1. The standard deviation in altitude is 12 m. We have validated the hot-air balloon derived wind data with observations from the Cabauw tower and the results are encouraging. We have studied the dynamics of a hot-air balloon. An empirical value of the response length has been found which accounts for the balloon’s inertia after a changing wind, and which compared favorable with the theoretical derived value. We have found a small but systematic movement of the hot-air balloon relative to the surrounding air. The model for the balloon dynamics has been refined to account for this so-called inertial drift.

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Komatsu, Kensuke K. y Yoshihiro Tachibana. "Two Types of Strong Local Wind Captured by Simultaneous Multiple-Site Radiosonde Soundings across a Mountain Range". Monthly Weather Review 144, n.º 10 (octubre de 2016): 3915–36. http://dx.doi.org/10.1175/mwr-d-15-0347.1.

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A radiosonde observation method is presented, consisting of simultaneous radiosonde observations at closely spaced multiple sites using balloons with varied buoyancies. This method was employed during a strong wind event (Suzuka-oroshi) on the lee side of the Suzuka mountain range, Japan, to derive the detailed structure of the wind as it crossed the mountains. Batches of six radiosondes were launched simultaneously from a line of four sites, using balloons with three different degrees of buoyancy. The four sites were 13 km apart along a 35-km-long transect roughly aligned with the prevailing wind. The observations documented two flow regimes: a downslope flow perpendicular to the mountain range, similar to a windstorm, and an unexpectedly strong low-level jet flowing parallel to the mountain range. The method was more successful at delineating the first regime than the second. The first regime was well simulated by a numerical experiment, but the second regime was not. The vertical wind associated with the downslope windstorm was inferred from the changing slopes of potential temperature isentropes. Comparison of the balloon ascent rates with these isentropes meanders and the simulated vertical wind showed that fluctuations in balloon ascent rate provide reliable information on the vertical direction of the wind. An analysis of the second regime using a long-term meteorological dataset shows that the onset of the low-level jet is related to the synoptic-scale shift in vorticity from positive to negative in the observation area. This vorticity shift appears to be a useful indicator for the low-level jet regime.

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Anisimov, S. V., K. V. Aphinogenov y A. V. Guriev. "HARDWARE PLATFORM FOR BALLOON AEROELECTRICAL OBSERVATIONS". NAUCHNOE PRIBOROSTROENIE 27, n.º 1 (28 de febrero de 2017): 24–28. http://dx.doi.org/10.18358/np-27-1-i2428.

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15

Rand, J. L. y M. L. Phillips. "A superpressure balloon for Mars observations". Advances in Space Research 30, n.º 5 (enero de 2002): 1245–50. http://dx.doi.org/10.1016/s0273-1177(02)00538-0.

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16

Agrawal, P. C. "Space Astronomy in India". Publications of the Astronomical Society of Australia 9, n.º 2 (1991): 229–33. http://dx.doi.org/10.1017/s1323358000023936.

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AbstractAstronomical observations from space-borne instruments are carried out in India in the areas of infrared, X-ray and gamma-ray astronomy. This paper briefly describes the facilities available in India for conducting experiments in space astronomy using balloons, rockets and satellites. It briefly reviews the important results obtained by Indian astronomers from observations made in India with the balloon, rocket and satellite experiments. The present status of research in different disciplines of space astronomy is discussed.

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de Bruijn, Evert I. F., Siebren de Haan, Fred C. Bosveld, Ben Wichers Schreur y Albert A. M. Holtslag. "Observing Boundary-Layer Winds from Hot-Air Balloon Flights". Weather and Forecasting 31, n.º 5 (23 de agosto de 2016): 1451–63. http://dx.doi.org/10.1175/waf-d-16-0028.1.

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Abstract High-resolution upper-air wind observations are sparse, and additional observations are a welcome source of meteorological information. In this paper the potential of applying balloon flights for upper-air wind measurements is explored, and the meteorological content of this information is investigated. The displacement of a hot-air balloon is a measure for the wind speed and direction and thus a potential source for wind observations in the lower part of the troposphere. The response time of the balloon on the changing wind is fast in the beginning and levels off for smaller relative wind speeds. Four case studies are presented, and the balloon-derived winds are compared with other wind observations and with results from the HIRLAM–ALADIN Research on Mesoscale Operational NWP in Europe (HARMONIE) model. It turns out that hot-air balloon tracks can indeed produce useful wind observations just above and in the atmospheric boundary layer (ABL).

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Hasebe, F., S. Aoki, S. Morimoto, Y. Inai, T. Nakazawa, S. Sugawara, C. Ikeda et al. "Coordinated Upper-Troposphere-to-Stratosphere Balloon Experiment in Biak". Bulletin of the American Meteorological Society 99, n.º 6 (junio de 2018): 1213–30. http://dx.doi.org/10.1175/bams-d-16-0289.1.

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AbstractThe stratospheric response to climate forcing, such as an increase in greenhouse gases, is often unpredictable because of interactions between radiation, dynamics, and chemistry. Climate models are unsuccessful in simulating the realistic distribution of stratospheric water vapor. The long-term trend of the stratospheric age of air (AoA), a measure that characterizes the stratospheric turnover time, remains inconsistent between diagnoses in climate models and estimates from tracer observations. For these reasons, observations designed specifically to distinguish the effects of individual contributing processes are required. Here, we report on the Coordinated Upper-Troposphere-to-Stratosphere Balloon Experiment in Biak (CUBE/Biak), an observation campaign organized in Indonesia. Being inside the “tropical pipe” makes it possible to study the dehydration in the tropical tropopause layer and the gradual ascent in the stratosphere while minimizing the effects of multiple circulation pathways and wave mixing. Cryogenic sampling of minor constituents and major isotopes was conducted simultaneously with radiosonde observations of water vapor, ozone, aerosols, and cloud particles. The water vapor “tape recorder,” gravitational separation, and isotopocules are being studied in conjunction with tracers that are accumulated in the atmosphere as dynamical and chemical measures of elapsed time since stratospheric air entry. The observational estimates concerning the AoA and water vapor tape recorder are compared with those derived from trajectory calculations.

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Hoffmann, Lars, Albert Hertzog, Thomas Rößler, Olaf Stein y Xue Wu. "Intercomparison of meteorological analyses and trajectories in the Antarctic lower stratosphere with Concordiasi superpressure balloon observations". Atmospheric Chemistry and Physics 17, n.º 13 (4 de julio de 2017): 8045–61. http://dx.doi.org/10.5194/acp-17-8045-2017.

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Abstract. In this study we compared temperatures and horizontal winds of meteorological analyses in the Antarctic lower stratosphere, a region of the atmosphere that is of major interest regarding chemistry and dynamics of the polar vortex. The study covers the European Centre for Medium-Range Weather Forecasts (ECMWF) operational analysis, the ERA-Interim reanalysis, the Modern-Era Retrospective analysis for Research and Applications version 1 and 2 (MERRA and MERRA-2), and the National Centers for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR) reanalysis. The comparison was performed with respect to long-duration observations from 19 superpressure balloon flights during the Concordiasi field campaign in September 2010 to January 2011. Most of the balloon measurements were conducted at altitudes of 17–18.5 km and latitudes of 60–85° S. We found that large-scale state temperatures of the analyses have a mean precision of 0.5–1.4 K and a warm bias of 0.4–2.1 K with respect to the balloon data. Zonal and meridional winds have a mean precision of 0.9–2.3 m s−1 and a bias below ±0.5 m s−1. Standard deviations related to small-scale fluctuations due to gravity waves are reproduced at levels of 15–60 % for temperature and 30–60 % for the horizontal winds. Considering the fact that the balloon observations have been assimilated into all analyses, except for NCEP/NCAR, notable differences found here indicate that other observations, the forecast models, and the data assimilation procedures have a significant impact on the analyses as well. We also used the balloon observations to evaluate trajectory calculations with our new Lagrangian transport model Massive-Parallel Trajectory Calculations (MPTRAC), where vertical motions of simulated trajectories were nudged to pressure measurements of the balloons. We found relative horizontal transport deviations of 4–12 % and error growth rates of 60–170 km day−1 for 15-day trajectories. Dispersion simulations revealed some difficulties with the representation of subgrid-scale wind fluctuations in MPTRAC, as the spread of air parcels simulated with different analyses was not consistent. However, although case studies suggest that the accuracy of trajectory calculations is influenced by meteorological complexity, diffusion generally does not contribute significantly to transport deviations in our analysis. Overall, evaluation results are satisfactory and compare well to earlier studies using superpressure balloon observations.

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Rao, P. Syamasundar. "Balloon Dilatation in the Management of Congenital Obstructive Lesions of the Heart: Review of Author’s Experiences and Observations—Part II". Journal of Cardiovascular Development and Disease 10, n.º 7 (6 de julio de 2023): 288. http://dx.doi.org/10.3390/jcdd10070288.

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While investigating the outcomes of balloon dilatation procedures in patients with congenital obstructive lesions of the heart, several parallel observations were made. The purpose of this review is to present these observations/phenomena/innovations related to balloon dilatation of pulmonary stenosis (PS), aortic stenosis (AS), and aortic coarctation (AC). In subjects who had balloon pulmonary valvuloplasty (BPV), development of infundibular obstruction, electrocardiographic (ECG) changes, changes in right ventricular filling, role of balloon/annulus ratios on the results of BPV, and double balloon vs. single balloon BPV will be reviewed. In patients who had balloon aortic valvuloplasty (BAV), causes of aortic insufficiency and trans-umbilical venous approach for BAV are tackled. In children who had balloon angioplasty (BA) of AC, aortic remodeling and biophysical response after BA of AC are discussed.

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Kotlarz, Jan y Natalia Zalewska. "The Possibility of Ultraviolet Enceladus’ Observations from Stratospheric Balloons". Transactions on Aerospace Research 2019, n.º 1 (1 de marzo de 2019): 17–27. http://dx.doi.org/10.2478/tar-2019-0002.

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Abstract Stratospheric balloons are very important sources for space and terrestrial observation experiments in many disciplines. Instruments developed for astrophysical measurements are usually reusable. It is also possible to observe both hemispheres including observations from the polar and equatorial regions for thirty days or even longer. On the other hand the UV atmospheric transmittance window was used for the astrophysical observations less often than visible optical bands. At the end of the 2017 there are a few scientific groups working on near-UV or UV spectrographs and cameras for balloon flights. In this paper we are discussing the possibility of ultraviolet measurement of Enceladus, an icy Saturnian moon, surface reflectance between 200 and 400 nm from the 20-50 km altitudes. At visible and near infrared optical channels Enceladus’ reflectance is very high (near 1.0). This value is consistent with a surface composed of water ice, however at some ultraviolet wavelengths Enceladus reflectance is lower than it would be expected for this type of surface. The scientific research done in the last decade was focused on H2O, NH3, and tholin particles detection on the Enceladus’ surface as a reason of low UV reflectance phenomenon. Continuous observation of Enceladus’ UV reflectance variability from stratospheric balloons may be interesting and may give us the proof of the presence of biomarkers or/and tholin particles.

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Zhang, Min, Pengfei Tian, Huiyu Zeng, Ligong Wang, Jiening Liang, Xianjie Cao y Lei Zhang. "A Comparison of Wintertime Atmospheric Boundary Layer Heights Determined by Tethered Balloon Soundings and Lidar at the Site of SACOL". Remote Sensing 13, n.º 9 (3 de mayo de 2021): 1781. http://dx.doi.org/10.3390/rs13091781.

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High-precision and -resolution atmospheric boundary layer height (BLH) has received increasing attention in air pollution research in recent years. The low time resolution of sounding data is the main challenge to validate BLH retrieval from lidar observations. To resolve this issue, we conducted simultaneous tethered balloon sounding and lidar observations at the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) during winter 2019–2020. The BLHs derived from the tethered balloon sounding data were 170, 210, 393, 676, 423, and 190 m at 02:00, 08:00, 11:00, 14:00, 17:00, and 20:00 (Beijing time), respectively. The diurnal evolution of BLH was reasonably captured by lidar observation-based wavelet covariance transform and ideal profile fitting methods, which exhibited correlation coefficients of 0.91 and 0.89, respectively, with the BLHs determined from tethered balloon sounding data. The lidar results slightly overestimated the BLHs, though all results were acceptable when considering both the absolute and relative errors with respect to BLHs from the tethered balloon data. Our results revealed high-precision and -resolution diurnal variations in BLH at SACOL in Northwest China and suggest the importance of validating lidar-based BLHs using simultaneous sounding data.

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23

Markowski, Paul M., Yvette P. Richardson, Scott J. Richardson y Anders Petersson. "Aboveground Thermodynamic Observations in Convective Storms from Balloonborne Probes Acting as Pseudo-Lagrangian Drifters". Bulletin of the American Meteorological Society 99, n.º 4 (abril de 2018): 711–24. http://dx.doi.org/10.1175/bams-d-17-0204.1.

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AbstractThe severe storms research community lacks reliable, aboveground, thermodynamic observations (e.g., temperature, humidity, and pressure) in convective storms. These missing observations are crucial to understanding the behavior of both supercell storms (e.g., the generation, reorientation, and amplification of vorticity necessary for tornado formation) and larger-scale (mesoscale) convective systems (e.g., storm maintenance and the generation of damaging straight-line winds). This paper describes a novel way to use balloonborne probes to obtain aboveground thermodynamic observations. Each probe is carried by a pair of balloons until one of the balloons is jettisoned; the remaining balloon and probe act as a pseudo-Lagrangian drifter that is drawn through the storm. Preliminary data are presented from a pair of deployments in supercell storms in Oklahoma and Kansas during May 2017. The versatility of the observing system extends beyond severe storms applications into any area of mesoscale meteorology in which a large array of aboveground, in situ thermodynamic observations are needed.

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24

Sen, B., G. C. Toon, J. F. Blavier, E. L. Fleming y C. H. Jackman. "Balloon-borne observations of midlatitude fluorine abundance". Journal of Geophysical Research: Atmospheres 101, n.º D4 (1 de abril de 1996): 9045–54. http://dx.doi.org/10.1029/96jd00227.

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25

Coy, L., M. R. Schoeberl, S. Pawson, S. Candido y R. W. Carver. "Global Assimilation of Loon Stratospheric Balloon Observations". Journal of Geophysical Research: Atmospheres 124, n.º 6 (18 de marzo de 2019): 3005–19. http://dx.doi.org/10.1029/2018jd029673.

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26

Engel, Andreas, Harald Bönisch, Markus Ullrich, Robert Sitals, Olivier Membrive, Francois Danis y Cyril Crevoisier. "Mean age of stratospheric air derived from AirCore observations". Atmospheric Chemistry and Physics 17, n.º 11 (12 de junio de 2017): 6825–38. http://dx.doi.org/10.5194/acp-17-6825-2017.

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Abstract. Mean age of stratospheric air can be derived from observations of sufficiently long-lived trace gases with approximately linear trends in the troposphere. Mean age can serve as a tracer to investigate stratospheric transport and long-term changes in the strength of the overturning Brewer–Dobson circulation of the stratosphere. For this purpose, a low-cost method is required in order to allow for regular observations up to altitudes of about 30 km. Despite the desired low costs, high precision and accuracy are required in order to determine mean age. We present balloon-borne AirCore observations from two midlatitude sites: Timmins in Ontario/Canada and Lindenberg in Germany. During the Timmins campaign, five AirCores sampled air in parallel with a large stratospheric balloon and were analysed for CO2, CH4 and partly CO. We show that there is good agreement between the different AirCores (better than 0.1 %), especially when vertical gradients are small. The measurements from Lindenberg were performed using small low-cost balloons and yielded very comparable results. We have used the observations to extend our long-term data set of mean age observations at Northern Hemisphere midlatitudes. The time series now covers more than 40 years and shows a small, statistically non-significant positive trend of 0.15 ± 0.18 years decade−1. This trend is slightly smaller than the previous estimate of 0.24 ± 0.22 years decade−1 which was based on observations up to the year 2006. These observations are still in contrast to strong negative trends of mean age as derived from some model calculations.

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27

Hole, Lars R., Alexis Pérez Bello, Tjarda J. Roberts, Paul B. Voss y Timo Vihma. "Measurements by controlled meteorological balloons in coastal areas of Antarctica". Antarctic Science 28, n.º 5 (6 de junio de 2016): 387–94. http://dx.doi.org/10.1017/s0954102016000213.

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AbstractAn experiment applying controlled meteorological (CMET) balloons near the coast of Dronning Maud Land, Antarctica, in January 2013 is described. Two balloons were airborne for 60 and 106 hours with trajectory lengths of 885.8 km and 2367.4 km, respectively. The balloons carried out multiple controlled soundings on the atmospheric pressure, temperature and humidity up to 3.3 km. Wind speed and direction were derived from the balloon drift. Observations were compared with radiosonde sounding profiles from the Halley Research Station, and applied in evaluating simulations carried out with the weather research and forecasting (WRF) mesoscale atmospheric model. The most interesting feature detected by the CMET balloons was a mesoscale anticyclone over the Weddell Sea and the coastal zone, which was reproduced by the WRF model with reduced intensity. The modelled wind speed was up to 10 m s-1 slower and the relative humidity was 20–40% higher than the observed values. However, over the study period the WRF results generally agreed with the observations. The results suggest that CMET balloons could be an interesting supplement to Antarctic atmospheric observations, particularly in the free troposphere.

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28

Ma, Y. Q., G. H. Li, C. M. Zhang, Q. Y. Xiao, Y. M. Qian, Z. G. Li, M. Wu et al. "A Hard X-ray Observation of CYG X-1 in 1985". Symposium - International Astronomical Union 125 (1987): 202. http://dx.doi.org/10.1017/s0074180900160759.

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On September 22, 1985, a hard X-ray observation of Cyg X-1 was performed by using a balloon-borne CsI-NaI phoswich telescope HAPI-2 at Xianghe Balloon Facility in China. The main detector is CsI(T1) with a thickness of 0.4cm and an area of 140cm2. The energy range is 20–200KeV. The telescope reached a float altitude of about 38Km(4g/cm2). The photon's arrival time and energy loss spectrum were measured for both background and active tracking on-source observations.

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29

Quintero Noda, C., G. L. Villanueva, Y. Katsukawa, S. K. Solanki, D. Orozco Suárez, B. Ruiz Cobo, T. Shimizu et al. "Solar polarimetry in the K I D2 line : A novel possibility for a stratospheric balloon". Astronomy & Astrophysics 610 (febrero de 2018): A79. http://dx.doi.org/10.1051/0004-6361/201732111.

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Of the two solar lines, K I D1 and D2, almost all attention so far has been devoted to the D1 line, as D2 is severely affected by an O2 atmospheric band. This, however, makes the latter appealing for balloon and space observations from above (most of) the Earth’s atmosphere. We estimate the residual effect of the O2 band on the K I D2 line at altitudes typical for stratospheric balloons. Our aim is to study the feasibility of observing the 770 nm window. Specifically, this paper serves as a preparation for the third flight of the Sunrise balloon-borne observatory. The results indicate that the absorption by O2 is still present, albeit much weaker, at the expected balloon altitude. We applied the obtained O2 transmittance to K I D2 synthetic polarimetric spectra and found that in the absence of line-of-sight motions, the residual O2 has a negligible effect on the K I D2 line. On the other hand, for Doppler-shifted K I D2 data, the residual O2 might alter the shape of the Stokes profiles. However, the residual O2 absorption is sufficiently weak at stratospheric levels that it can be divided out if appropriate measurements are made, something that is impossible at ground level. Therefore, for the first time with Sunrise III, we will be able to perform polarimetric observations of the K I D2 line and, consequently, we will have improved access to the thermodynamics and magnetic properties of the upper photosphere from observations of the K I lines.

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30

Businger, S., R. Johnson y R. Talbot. "Scientific Insights from Four Generations of Lagrangian Smart Balloons in Atmospheric Research*". Bulletin of the American Meteorological Society 87, n.º 11 (1 de noviembre de 2006): 1539–54. http://dx.doi.org/10.1175/bams-87-11-1539.

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This paper provides an overview of the trials and successes in the development of an autonomous balloon instrument platform (smart balloon) and reviews scientific insights gained through its employment as a marker in a Lagrangian strategy during recent field experiments. The smart balloons are designed and constructed at the National Oceanic and Atmospheric Administration Air Resources Laboratory Field Research Division in collaboration with the University of Hawaii. In a 2004 field deployment a smart balloon carrying a miniature ozone sensor successfully crossed the Atlantic Ocean from Long Island, New York, to the African coast of Morocco. Significant progress has been made through field experiments such as this in our understanding of the relationships between the evolution of marine boundary layers and the chemistry of aerosol and gaseous constituents in clean and polluted air masses. Innovation in design and advances in instrument and communication technology have opened a dramatic new range of applications for the smart balloon in atmospheric research, including, for example, the interesting prospect of making observations very near the ocean surface in hurricanes and typhoons, which are not possible with research aircraft.

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31

Kezoudi, Maria, Matthias Tesche, Helen Smith, Alexandra Tsekeri, Holger Baars, Maximilian Dollner, Víctor Estellés et al. "Measurement report: Balloon-borne in situ profiling of Saharan dust over Cyprus with the UCASS optical particle counter". Atmospheric Chemistry and Physics 21, n.º 9 (5 de mayo de 2021): 6781–97. http://dx.doi.org/10.5194/acp-21-6781-2021.

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Abstract. This paper presents measurements of mineral dust concentration in the diameter range from 0.4 to 14.0 µm with a novel balloon-borne optical particle counter, the Universal Cloud and Aerosol Sounding System (UCASS). The balloon launches were coordinated with ground-based active and passive remote-sensing observations and airborne in situ measurements with a research aircraft during a Saharan dust outbreak over Cyprus from 20 to 23 April 2017. The aerosol optical depth at 500 nm reached values up to 0.5 during that event over Cyprus, and particle number concentrations were as high as 50 cm−3 for the diameter range between 0.8 and 13.9 µm. Comparisons of the total particle number concentration and the particle size distribution from two cases of balloon-borne measurements with aircraft observations show reasonable agreement in magnitude and shape despite slight mismatches in time and space. While column-integrated size distributions from balloon-borne measurements and ground-based remote sensing show similar coarse-mode peak concentrations and diameters, they illustrate the ambiguity related to the missing vertical information in passive sun photometer observations. Extinction coefficient inferred from the balloon-borne measurements agrees with those derived from coinciding Raman lidar observations at height levels with particle number concentrations smaller than 10 cm−3 for the diameter range from 0.8 to 13.9 µm. An overestimation of the UCASS-derived extinction coefficient of a factor of 2 compared to the lidar measurement was found for layers with particle number concentrations that exceed 25 cm−3, i.e. in the centre of the dust plume where particle concentrations were highest. This is likely the result of a variation in the refractive index and the shape and size dependency of the extinction efficiency of dust particles along the UCASS measurements. In the future, profile measurements of the particle number concentration and particle size distribution with the UCASS could provide a valuable addition to the measurement capabilities generally used in field experiments that are focussed on the observation of coarse aerosols and clouds.

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32

Cao, Bing, Jennifer S. Haase, Michael J. Murphy, M. Joan Alexander, Martina Bramberger y Albert Hertzog. "Equatorial waves resolved by balloon-borne Global Navigation Satellite System radio occultation in the Strateole-2 campaign". Atmospheric Chemistry and Physics 22, n.º 23 (5 de diciembre de 2022): 15379–402. http://dx.doi.org/10.5194/acp-22-15379-2022.

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Abstract. Current climate models have difficulty representing realistic wave–mean flow interactions, partly because the contribution from waves with fine vertical scales is poorly known. There are few direct observations of these waves, and most models have difficulty resolving them. This observational challenge cannot be addressed by satellite or sparse ground-based methods. The Strateole-2 long-duration stratospheric superpressure balloons that float with the horizontal wind on constant-density surfaces provide a unique platform for wave observations across a broad range of spatial and temporal scales. For the first time, balloon-borne Global Navigation Satellite System (GNSS) radio occultation (RO) is used to provide high-vertical-resolution equatorial wave observations. By tracking navigation signal refractive delays from GPS satellites near the horizon, 40–50 temperature profiles were retrieved daily, from balloon flight altitude (∼20 km) down to 6–8 km altitude, forming an orthogonal pattern of observations over a broad area (±400–500 km) surrounding the flight track. The refractivity profiles show an excellent agreement of better than 0.2 % with co-located radiosonde, spaceborne COSMIC-2 RO, and reanalysis products. The 200–500 m vertical resolution and the spatial and temporal continuity of sampling make it possible to extract properties of Kelvin waves and gravity waves with vertical wavelengths as short as 2–3 km. The results illustrate the difference in the Kelvin wave period (20 vs. 16 d) in the Lagrangian versus ground-fixed reference and as much as a 20 % difference in amplitude compared to COSMIC-2, both of which impact estimates of momentum flux. A small dataset from the extra Galileo, GLONASS, and BeiDou constellations demonstrates the feasibility of nearly doubling the sampling density in planned follow-on campaigns when data with full equatorial coverage will contribute to a better estimate of wave forcing on the quasi-biennial oscillation (QBO) and improved QBO representation in models.

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33

Hertzog, Albert, Gillian Boccara, Robert A. Vincent, François Vial y Philippe Cocquerez. "Estimation of Gravity Wave Momentum Flux and Phase Speeds from Quasi-Lagrangian Stratospheric Balloon Flights. Part II: Results from the Vorcore Campaign in Antarctica". Journal of the Atmospheric Sciences 65, n.º 10 (octubre de 2008): 3056–70. http://dx.doi.org/10.1175/2008jas2710.1.

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The stratospheric gravity wave field in the Southern Hemisphere is investigated by analyzing observations collected by 27 long-duration balloons that flew between September 2005 and February 2006 over Antarctica and the Southern Ocean. The analysis is based on the methods introduced by Boccara et al. in a companion paper. Special attention is given to deriving information useful to gravity wave drag parameterizations employed in atmospheric general circulation models. The balloon dataset is used to map the geographic variability of gravity wave momentum fluxes in the lower stratosphere. This flux distribution is found to be very heterogeneous with the largest time-averaged value (28 mPa) observed above the Antarctic Peninsula. This value exceeds by a factor of ∼10 the overall mean momentum flux measured during the balloon campaign. Zonal momentum fluxes were predominantly westward, whereas meridional momentum fluxes were equally northward and southward. A local enhancement of southward flux is nevertheless observed above Adélie Land and is attributed to waves generated by katabatic winds, for which the signature is otherwise rather small in the balloon observations. When zonal averages are performed, oceanic momentum fluxes are found to be of similar magnitude to continental values (2.5–3 mPa), stressing the importance of nonorographic gravity waves over oceans. Last, gravity wave intermittency is investigated. Mountain waves appear to be significantly more sporadic than waves observed above the ocean.

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34

Rao, P. Syamasundar. "Pictorial rendition of author’s observations on balloon valvuloplasty/angioplasty procedures: Pulmonary stenosis". Brain & Heart 2, n.º 1 (15 de febrero de 2024): 2406. http://dx.doi.org/10.36922/bh.2406.

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Balloon valvuloplasty/angioplasty techniques have been available to address valvar and vascular obstructions associated with congenital heart defects (CHDs) since the 1980s. The objective of this paper is to provide a pictorial rendition of the author’s observations over the last four decades on these techniques. In this paper, balloon pulmonary valvuloplasty (BPV) for treating isolated pulmonary stenosis (PS), PS associated with cyanotic CHDs, and bioprosthetic valve in the pulmonary position were reviewed. Balloon dilatation leads to a decrease in the peak systolic pressure gradient through the pulmonary valve during BPV, as well as at intermediate-term and long-term evaluation. Problems, such as the reappearance of obstruction at intermediate-term follow-up and pulmonary insufficiency (PI) at long-term follow-up, have been documented in isolated PS cases but are infrequent. Repeat balloon valvuloplasty for restenosis has been successfully used. The development of infundibular obstruction in PS cases was also reviewed. To decrease the frequency and degree of PI, the author has revised the recommendations for balloon/annulus ratios used for BPV from the previous 1.2 – 1.4 to 1.2 – 1.25. In patients with PS associated with cyanotic CHD, improvement of oxygen saturations at the time of BPV and enhanced anatomy during follow-up were observed. BPV of bioprosthetic valves results in minimal improvement in the pulmonary valve gradient, and stents may be a better alternative to address this problem.

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35

Tilmes, S., R. Müller, R. J. Salawitch, U. Schmidt, C. R. Webster, H. Oelhaf, J. M. Russell III y C. C. Camy-Peyret. "Chemical ozone loss in the Arctic winter 1991–1992". Atmospheric Chemistry and Physics Discussions 7, n.º 4 (12 de julio de 2007): 10097–129. http://dx.doi.org/10.5194/acpd-7-10097-2007.

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Abstract. Chemical ozone loss in winter 1991–1992 is recalculated based on observations of the HALOE satellite instrument, ER-2 aircraft measurements and balloon data. HALOE satellite observations are shown to be reliable in the lower stratosphere below 400 K, at altitudes where profiles are most likely disturbed by the enhanced sulfate aerosols, as a result of the Mt. Pinatubo eruption in June 1991. Very large chemical ozone loss was observed below 400 K from Kiruna balloon observations between December and March 1992. Additionally, for the two winters after the Mt. Pinatubo eruption, HALOE satellite observations show a stronger extent of chemical ozone loss at lower altitudes compared to other Arctic winter between 1991 and 2003. In stipe of already occurring deactivation of chlorine in March 1992, Mipas-B and LPMA balloon observations indicate still chlorine activation at lower altitudes, consistent with observed chemical ozone loss occurring between February and March and April. Enhanced chemical ozone loss in the Arctic winter 1991–1992 as calculated in earlier studies is corroborated here.

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36

Nishimura, Rick A., David R. Holmes, Guy S. Reeder, A. Jamil Tajik y Liv K. Hatle. "Doppler echocardiographic observations during percutaneous aortic balloon valvuloplasty". Journal of the American College of Cardiology 11, n.º 6 (junio de 1988): 1219–26. http://dx.doi.org/10.1016/0735-1097(88)90285-9.

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37

Sen, B., G. C. Toon, J. F. Blavier, J. T. Szeto, E. L. Fleming y C. H. Jackman. "Balloon-borne observations of mid-latitude hydrofluoric acid". Geophysical Research Letters 22, n.º 7 (1 de abril de 1995): 835–38. http://dx.doi.org/10.1029/95gl00006.

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38

Deuzé, J. L., C. Devaux, M. Herman, R. Santer, J. Y. Balois, L. Gonzalez, P. Lecomte y C. Verwaerde. "Photopolarimetric observations of aerosols and clouds from balloon". Remote Sensing of Environment 29, n.º 2 (agosto de 1989): 93–109. http://dx.doi.org/10.1016/0034-4257(89)90019-9.

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39

Bolton, P. y C. J. P. Cave. "Computation of wind velocity from pilot balloon observations". Quarterly Journal of the Royal Meteorological Society 44, n.º 185 (15 de agosto de 2007): 31–40. http://dx.doi.org/10.1002/qj.49704418506.

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40

Mironova, Irina, Galina Bazilevskaya, Vladimir Makhmutov, Andrey Mironov y Nikita Bobrov. "Energetic Electron Precipitation via Satellite and Balloon Observations: Their Role in Atmospheric Ionization". Remote Sensing 15, n.º 13 (27 de junio de 2023): 3291. http://dx.doi.org/10.3390/rs15133291.

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Information about the energetic electron precipitation (EEP) from the radiation belt into the atmosphere is important for assessing the ozone variability and dynamics of the middle atmosphere during magnetospheric and geomagnetic disturbances. The accurate values of energetic electron fluxes depending on their energy range are one of the most important problems for calculating atmospheric ionization rates, which, in turn, are taken into account for estimating ozone depletion in chemistry–climate models. Despite the importance of these processes for the high latitudes of middle atmosphere, precipitation of energetic electrons is still insufficiently studied. In order to better understand EEP and related processes in the atmosphere, it is important to have many realistic observations of EEP in order to correctly characterize their spectra. Invading the atmosphere, precipitating energetic electrons, in the range from tens of keV to relativistic energies of more than 1 MeV, generate bremsstrahlung, which penetrates into the stratosphere and is recorded by detectors on balloons. However, these observations can be made only when the balloon is at stratospheric heights. Near-Earth satellites, such as the polar-orbiting operational environmental satellites (POES), are constantly registering precipitating electrons in the loss cone, but are moving too fast in space. Based on a comparison of the results of EEP measurements on balloons and onboard POES satellites in 2003, we propose a criterion that makes it possible to constantly monitor EEP ionization at stratospheric heights using observations on POES satellites.

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41

Hooghiem, Joram J. D., Maria Elena Popa, Thomas Röckmann, Jens-Uwe Grooß, Ines Tritscher, Rolf Müller, Rigel Kivi y Huilin Chen. "Wildfire smoke in the lower stratosphere identified by in situ CO observations". Atmospheric Chemistry and Physics 20, n.º 22 (19 de noviembre de 2020): 13985–4003. http://dx.doi.org/10.5194/acp-20-13985-2020.

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Abstract. Wildfires emit large quantities of aerosols and trace gases, which occasionally reach the lower stratosphere. In August 2017, several pyro-cumulonimbus events injected a large amount of smoke into the stratosphere, observed by lidar and satellites. Satellite observations are in general the main method of detecting these events since in situ aircraft- or balloon-based measurements of atmospheric composition at higher altitudes are not made frequently enough. This work presents accidental balloon-borne trace gas observations of wildfire smoke in the lower stratosphere, identified by enhanced CO mole fractions at approximately 13.6 km. In addition to CO mole fractions, CO2 mole fractions and isotopic composition of CO (δ13C and δ18O) have been measured in air samples, from both the wildfire plume and background, collected using an AirCore and a lightweight stratospheric air sampler (LISA) flown on a weather balloon from Sodankylä (4–7 September 2017; 67.37∘ N, 26.63∘ E; 179 m a.m.s.l.), Finland. The greenhouse gas enhancement ratio (ΔCO:ΔCO2) and the isotopic signature based on δ13C(CO) and δ18O(CO) independently identify wildfire emissions as the source of the stratospheric CO enhancement. Back-trajectory analysis was performed with the Chemical Lagrangian Model of the Stratosphere (CLaMS), tracing the smoke's origin to wildfires in British Columbia with an injection date of 12 August 2017. The trajectories are corrected for vertical displacement due to heating of the wildfire aerosols, by observations made by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument. Knowledge of the age of the smoke allowed for a correction of the enhancement ratio, ΔCO:ΔCO2, for the chemical removal of CO by OH. The stable isotope observations were used to estimate the amount of tropospheric air in the plume at the time of observation to be about 45±21 %. Finally, the plume extended over 1 km in altitude, as inferred from the observations.

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42

Voggenberger, Ulrich, Leopold Haimberger, Federico Ambrogi y Paul Poli. "Balloon drift estimation and improved position estimates for radiosondes". Geoscientific Model Development 17, n.º 9 (13 de mayo de 2024): 3783–99. http://dx.doi.org/10.5194/gmd-17-3783-2024.

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Abstract. When comparing model output with historical radiosonde observations, it is usually assumed that a radiosonde has risen exactly above its starting point and has not been displaced by wind. This changed only relatively recently with the availability of Global Navigation Satellite System (GNSS) receivers aboard radiosondes in the late 1990s, but even then the balloon trajectory data were often not transmitted, although this information was the basis for estimating the wind in the first place. Depending on the conditions and time of year, radiosondes can sometimes drift a few hundred kilometres, particularly at the middle latitudes during the winter months. The position errors can lead to non-negligible representation errors when the corresponding observations are assimilated. This paper presents a methodology to compute changes in the balloon position during its vertical ascent, using only limited information, such as the vertical profile of wind contained in the historical observation reports. The sensitivity of the method to various parameters is investigated, such as the vertical resolution of the input data, the assumption about the vertical ascent speed of the balloon, and the departure of the surface of Earth from a sphere. The paper considers modern GNSS sonde data reports for validation, for which the full trajectory of the balloon is available, alongside the reported wind. Evaluation is also conducted by comparison with ERA5 and by conducting low-resolution data assimilation experiments. Overall, the results indicate that the trajectory of the radiosondes can be accurately reconstructed from original data of varying vertical resolutions and that the more accurate balloon position reduces representation errors and, in some cases, systematic errors.

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43

Tilmes, S., R. Müller, R. J. Salawitch, U. Schmidt, C. R. Webster, H. Oelhaf, C. C. Camy-Peyret y J. M. Russell. "Chemical ozone loss in the Arctic winter 1991–1992". Atmospheric Chemistry and Physics 8, n.º 7 (31 de marzo de 2008): 1897–910. http://dx.doi.org/10.5194/acp-8-1897-2008.

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Abstract. Chemical ozone loss in winter 1991–1992 is recalculated based on observations of the HALOE satellite instrument, Version 19, ER-2 aircraft measurements and balloon data. HALOE satellite observations are shown to be reliable in the lower stratosphere below 400 K, at altitudes where the measurements are most likely disturbed by the enhanced sulfate aerosol loading, as a result of the Mt.~Pinatubo eruption in June 1991. Significant chemical ozone loss (13–17 DU) is observed below 380 K from Kiruna balloon observations and HALOE satellite data between December 1991 and March 1992. For the two winters after the Mt. Pinatubo eruption, HALOE satellite observations show a stronger extent of chemical ozone loss towards lower altitudes compared to other Arctic winters between 1991 and 2003. In spite of already occurring deactivation of chlorine in March 1992, MIPAS-B and LPMA balloon observations indicate that chlorine was still activated at lower altitudes, consistent with observed chemical ozone loss occurring between February and March and April. Large chemical ozone loss of more than 70 DU in the Arctic winter 1991–1992 as calculated in earlier studies is corroborated here.

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44

Park, Jongyeob, Jae-Ok Lee, Jihun Kim, Su-Chan Bong, Kyung-Suk Cho, Seonghwan Choi, Bi-Ho Jang et al. "Application of NASA core Flight System to Telescope Control Software for 2017 Total Solar Eclipse Observation". Publications of the Astronomical Society of the Pacific 134, n.º 1033 (1 de marzo de 2022): 034504. http://dx.doi.org/10.1088/1538-3873/ac5848.

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Abstract The core Flight System (cFS), developed by NASA, is a reusable software framework and a set of pluggable software applications that take advantage of the rich heritage of NASA’s successful space missions. We applied the cFS to the development of telescope control software for the observation of the 2017 total solar eclipse. Four main modules were developed: imaging control, mechanism control, data handling, and automated observation. Other modules, such as communication and scheduler, were reused from the cFS. Using an integrated observation system, we successfully observed the total solar eclipse, in which the linearly polarized brightness of the solar corona and sky background were measured at four different wavelengths. In this study, we demonstrated the usefulness of the cFS to develop telescope control software through an eclipse observation system, the so-called DICE (DIagnostic Coronagraph Experiment) mission. Our experience and knowledge of the cFS were expanded to a flight software BITSE (Balloon-borne Investigation of Temperature and Speed of Electrons in the corona), the high-altitude scientific balloon mission in 2019. We plan to apply this approach to future solar coronagraph observations, such as CODEX (COronal Diagnostic EXperiment), on the International Space Station. We expect that the cFS can also be applied in telescope control software for ground-and space-based observations.

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45

Nash, J. "Upper wind observing systems used for meteorological operations". Annales Geophysicae 12, n.º 8 (31 de julio de 1994): 691–710. http://dx.doi.org/10.1007/s00585-994-0691-2.

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Abstract. Methods of upper wind measurements used in operational meteorology have been reviewed to provide guidance to those developing wind profiler radar systems. The main limitations of the various methods of tracking weather balloons are identified using results from the WMO radiosonde comparisons and additional tests in the United Kingdom. Costs associated with operational balloon measurements are reviewed. The sampling and quality of operational aircraft wind observations are illustrated with examples from the ASDAR system. Measurement errors in horizontal winds are quantified wherever possible. When tracking equipment is functioning correctly, random errors in southerly and westerly wind component measurements from aircraft and weather balloons are usually in the range 0.5-2 m s-1.

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46

TAMAI, Masahiro y Jin TORIYAMA. "Field Observations of Nocturnal Drainages in the Northern Osaka Plain by Pilot Balloon Observation". Journal of Japan Society of Civil Engineers, Ser. G (Environmental Research) 69, n.º 7 (2013): III_205—III_213. http://dx.doi.org/10.2208/jscejer.69.iii_205.

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47

Herdies, Dirceu L., Vernon E. Kousky y Wesley Ebisuzaki. "The Impact of High-Resolution SALLJEX Data on Global NCEP Analyses". Journal of Climate 20, n.º 23 (1 de diciembre de 2007): 5765–83. http://dx.doi.org/10.1175/2007jcli1375.1.

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Abstract A data assimilation study was performed to assess the impact of observations from the South American Low-Level Jet Experiment (SALLJEX) on analyses in the region east of the Andes Mountains from western Brazil to central Argentina. The Climate Data Assimilation Systems (CDAS)-1 and -2 and the Global Data Assimilation System (GDAS) were run with and without the additional SALLJEX rawinsondes and pilot balloon observations. The experiments for each data assimilation system revealed similar features, with a stronger low-level flow east of the Andes when SALLJEX data were included. GDAS had the strongest low-level jet (LLJ) when compared with observations. In the experiments that used additional rawinsonde and pilot balloon data, the LLJ was displaced westward in comparison to the analyses run without the SALLJEX data. The vertical structure of the meridional wind in the analyses was much closer to observed rawinsonde profiles in the experiments that included SALLJEX data than in the control experiments, and the results show that, although there are more pilot balloon observations than rawinsonde observations in the SALLJEX dataset, most of the improvements in the analyses can be obtained by only including rawinsonde observations. This was especially true for GDAS. The results of this study can serve as a benchmark for similar data impact studies using higher-resolution data assimilation systems.

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48

Katz, Edward S., Paul A. Tunick y Itzhak Kronzon. "Observations of coronary flow augmentation and balloon function during intraaortic balloon counterpulsation using transesophageal echocardiography". American Journal of Cardiology 69, n.º 19 (junio de 1992): 1635–39. http://dx.doi.org/10.1016/0002-9149(92)90716-c.

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49

Parker, Geoffrey G., Peter J. Stone y David Bowers. "A Balloon for Microclimate Observations Within the Forest Canopy". Journal of Applied Ecology 33, n.º 1 (febrero de 1996): 173. http://dx.doi.org/10.2307/2405026.

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50

Davis, K. J., D. H. Lenschow y P. R. Zimmerman. "Biogenic nonmethane hydrocarbon emissions estimated from tethered balloon observations". Journal of Geophysical Research 99, n.º D12 (1994): 25587. http://dx.doi.org/10.1029/94jd02009.

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