The PMC Turbo Balloon Mission to Measure Gravity Waves and Turbulence in Polar Mesospheric Clouds: Camera, Telemetry, and Software Performance

Kjellstrand, C. B.; Jones, Glenn; Geach, Christopher; Williams, B. P.; Fritts, David C.; Miller, Amber; Hanany, Shaul; Limon, M.; Reimuller, Jason

doi:10.1029/2020ea001238

Cited by 9 publications

(8 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PMC Turbo flew for 5.9 days in July of 2018 from Kiruna, Sweden to Nunavut, Canada, approximately tracking the Arctic Circle. For an overview of the instrumentation, image processing, underlying weather, and a list and examples of the range of instability dynamics observed during flight, see Fritts, Miller, et al (2019) and Kjellstrand et al (2020).…”

Section: Pmc Turbo Instrumentation and Datamentioning

confidence: 99%

Gravity Wave Breaking and Vortex Ring Formation Observed by PMC Turbo

et al. 2020

Self Cite

View full text Add to dashboard Cite

Polar mesospheric cloud (PMC) imaging and lidar profiling performed aboard the 5.9-day PMC Turbo balloon flight from Sweden to northern Canada in July 2018 revealed a wide variety of gravity wave (GW) and instability events occurring nearly continuously at approximately 82 km. We describe one event exhibiting GW breaking and associated vortex rings driven by apparent convective instability. Using PMC Turbo imaging with spatial and temporal resolution of 20 m and 2 s, respectively, we quantify the GW horizontal wavelength, propagation direction, and apparent phase speed. We identify vortex rings with diameters of 2-5 km and horizontal spacing comparable to their size. Lidar data show GW vertical displacements of ±0.3 km. From the data, we find a GW intrinsic frequency and vertical wavelength of 0.009 ± 0.003 rad s −1 and 9 ± 4 km, respectively. We show that these values are consistent with the predictions of numerical simulations of idealized GW breaking. We estimate the momentum deposition rate per unit mass during this event to be 0.04 ± 0.02 m s −2 and show that this value is consistent with the observed GW. Comparison to simulation gives a mean energy dissipation rate for this event of 0.05-0.4 W kg −1 , which is consistent with other reported in situ measurements at the Arctic summer mesopause.

show abstract

Section: Pmc Turbo Instrumentation and Datamentioning

confidence: 99%

Gravity Wave Breaking and Vortex Ring Formation Observed by PMC Turbo

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…The PMC Turbo mission was designed to acquire quasi-3d soundings of the PMC layer by using a combination of camera and lidar observations at high resolution, as it is only at scales below one minute and tens of meters that the fine structures imprinted by dynamical instabilities during the breaking of gravity waves and the transition to turbulence become evident (Fritts et al, 2019). Besides the BOLIDE lidar, the scientific payload consisted of four wide-field-of-view and three narrow-field-ofview cameras (Kjellstrand et al, 2020). In this work, we describe and characterize the BOLIDE PMC dataset available from zenodo (Kaifler, 2021) and NASA's Space Physics Data Facility (see Sec.…”

Section: Introductionmentioning

confidence: 99%

“…At the average speed of 12.1 m/s of the laser beam at the height of the PMC layer, one 10-s-lidar profile averages over a horizontal distance of 121 m. The spot size of the laser beam at the PMC layer follows from the mean divergence of the laser beam and the slant range. Using a mean divergence angle of 67 µrad , the calculated spot size is 6.3 m. The position of the lidar beam is fixed relative to the FOVs of PMC Turbo's camera systems, 100 which have a pixel size at the position of the lidar beam of 3 m and 8 m, respectively (Kjellstrand et al, 2020) 2018 (Geach et al, 2020). Applying tracking algorithms to small-scale features in series of images acquired by the on-board cameras, the local wind speed can also be derived from measurements (Geach et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

The polar mesospheric cloud dataset of the Balloon Lidar Experiment BOLIDE

Kaifler

Kaifler²,

Rapp³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. The Balloon Lidar Experiment (BOLIDE) observed polar mesospheric clouds (PMC) along the Arctic circle between Sweden and Canada during the balloon flight of PMC Turbo in July 2018. The purpose of the mission was to study small-scale dynamical processes induced by the breaking of atmospheric gravity waves by high-resolution imaging and profiling of the PMC layer. The primary measured variable of the lidar soundings is the time- and range-resolved volume backscatter coefficient β. These data are available at high resolution of 20 m and 10 s (Kaifler, 2021, https://zenodo.org/record/5722385). This document describes how we calculate β from the BOLIDE photon count data and balloon floating altitude. We compile information relevant for the scientific exploration of this dataset, including statistics, mean values and temporal evolution of parameters like PMC brightness, altitude and occurrence rate. Special emphasis is given to the stability of the gondola pointing, and the effect of resolution on the signal-to-noise ratio and thus the detection threshold of PMC. PMC layers were detected during 49.7 h in total, accounting for 36.8 % of the 5.7 days flight duration and a total of 178924 PMC profiles at 10 s resolution. Up to the present, published results from subsets of this dataset include the evolution of small-scale vortex rings, distinct Kelvin-Helmholtz instabilities and two pronounced mesospheric bores. The lidar soundings reveal a wide range of responses of the PMC layer to larger-scale gravity waves and breaking gravity waves including accompanying instabilities that await scientific analysis.

show abstract

“…Among the millions of images acquired during the PMC Turbo mission were intriguing displays of small-scale vortex rings (Geach et al, 2020), Kelvin-Helmholtz instabilities (Kjellstrand et al) and mesospheric bores (Fritts et al, 2020). The selection of these events was mainly based on the interpretation of the images that were postprocessed to enhance small-scale structure (Kjellstrand et al, 2020) and make up only the tip of an iceberg of potentially interesting observations. Colocated lidar data have in all cases revealed significant small-scale structures with signatures that are likely inherent to the dynamic processes studied.…”

Section: Introductionmentioning

confidence: 99%

Signatures of gravity wave-induced instabilities in balloon lidar soundings of polar mesospheric clouds

Kaifler

Kaifler²,

Rapp³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. The Balloon Lidar Experiment (BOLIDE) which was part of the PMC Turbo balloon mission has captured near-vertical profiles of polar mesospheric clouds (PMC) during a 6-day flight along the Arctic circle in July 2018. The high-resolution soundings (20 m vertical and 10 s temporal resolution) reveal highly structured layers with large gradients in volume backscatter coefficient. We systematically screen the BOLIDE dataset for small-scale variability by assessing these gradients at high resolution. We find longer tails of the probability density distributions of these gradients compared to a normal distribution, indicating intermittent behaviour. The high occurrence rate of large gradients is assessed in relation to the 15-min-averaged layer brightness and the spectral power of short-period (5–62 min) gravity waves based on PMC layer altitude variations. We find that variability on small scales occurs during weak, moderate and strong gravity wave activity. Layers with below-average brightness are less likely to show small-scale variability in conditions of strong gravity wave activity. We present and discuss signatures of this small-scale variability and possibly related dynamical processes, and identify potential cases for future case studies and modelling efforts.

show abstract

The PMC Turbo Balloon Mission to Measure Gravity Waves and Turbulence in Polar Mesospheric Clouds: Camera, Telemetry, and Software Performance

Cited by 9 publications

References 18 publications

Gravity Wave Breaking and Vortex Ring Formation Observed by PMC Turbo

Gravity Wave Breaking and Vortex Ring Formation Observed by PMC Turbo

The polar mesospheric cloud dataset of the Balloon Lidar Experiment BOLIDE

Signatures of gravity wave-induced instabilities in balloon lidar soundings of polar mesospheric clouds

Contact Info

Product

Resources

About