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Vestibular migraine (VM) is an increasingly recognized pathology yet remains as an underdiagnosed cause of vestibular disorders. While current diagnostic criteria are codified in the 2012 Barany Society document and included in the third edition of the international classification of headache disorders, the pathophysiology of this disorder is still elusive. The Association for Migraine Disorders hosted a multidisciplinary, international expert workshop in October 2020 and identified seven current care gaps that the scientific community needs to resolve, including a better understanding of the range of symptoms and phenotypes of VM, the lack of a diagnostic marker, a better understanding of pathophysiologic mechanisms, as well as the lack of clear recommendations for interventions (nonpharmacologic and pharmacologic) and finally, the need for specific outcome measures that will guide clinicians as well as research into the efficacy of interventions. The expert group issued several recommendations to address those areas including establishing a global VM registry, creating an improved diagnostic algorithm using available vestibular tests as well as others that are in development, conducting appropriate trials of high quality to validate current clinically available treatment and fostering collaborative efforts to elucidate the pathophysiologic mechanisms underlying VM, specifically the role of the trigemino-vascular pathways.

Both enhanced motion-induced nausea and increased static imbalance are observed symptoms in migraine and especially vestibular migraine (VM). Motion-induced nausea and static imbalance were investigated in a mouse model, nestin/hRAMP1, expressing elevated levels of human RAMP1 which enhances CGRP signaling in the nervous system, and compared to non-affected littermate controls. Behavioral surrogates such as the motion-induced thermoregulation and postural sway center of pressure (CoP) assays were used to assess motion sensitivity. Nausea readouts revealed that the nestin/hRAMP1 mouse exhibit an increased sensitivity to CGRP's effects at lower doses compared to unaffected controls. In addition, the nestin/hRAMP1 mice exhibit a higher dynamic range in postural sway than their wildtype counterparts, along with increased sway observed in nestin/hRAMP1 male mice that was not present in male unaffected controls. Results from migraine blocker experiments were challenging to interpret, but the data suggests that olcegepant is incapable of reversing CGRP-induced or endogenous alterations in the nestin/hRAMP1 mice, while rizatriptan was ineffective in both the nestin/hRAMP1 and control mice. The results indicate that overexpression of hRAMP1 leads to heightened endogenous CGRP signaling. Results also suggest that both olcegepant and rizatriptan are ineffective in reducing nausea and sway in this hypersensitive CGRP mouse model. This study suggests that the hypersensitive nestin/hRAMP1 mouse may serve as a model for difficult to treat cases of migraine that exhibit increased motion sensitivity. [ABSTRACT FROM AUTHOR]

In two case studies, airborne measurements of broadband solar irradiances above and below Arctic cirrus are compared to simulations of the Integrated Forecasting System (IFS) operated by the European Centre for Medium-Range Weather Forecasts (ECMWF) using offline runs of ECMWF's operational radiation scheme, "ecRad". Furthermore, independent of the solar irradiances, cirrus properties are derived from collocated airborne active remote sensing observations to evaluate the optical and microphysical parameterizations in ecRad. The data were collected in the central Arctic over sea ice (81 – 90° N) with instrumentation installed aboard the High Altitude LOng range research aircraft (HALO) during a campaign in March and April 2022. Among others, the HALO instrumentation included upward- and downward-looking pyranometers to measure broadband solar irradiances, a cloud radar, and a multi-wavelength water vapour differential absorption lidar. Extended horizontal flight legs above and below single-layer cirrus were performed. The solar radiation measurements are used to evaluate ecRad in two case studies of optically thin and thick cirrus, with an average transmissivity of 0.9 and 0.6, respectively. Different ice optics parameterizations optionally available in ecRad are applied to test the match between simulation and measurements. Furthermore, the IFS-predicted ice water content and ice effective radius are replaced by values retrieved with the radar and lidar. The choice of ice optics parameterizations does not significantly improve the model–measurement agreement. However, introducing the retrieved ice microphysical properties brings measured and modelled irradiances in closer agreement for the optically thin cirrus, while the optically thick cirrus case is simulated as too thick. It is concluded that the ice water content simulated by the IFS is realistic and that the mismatch between observed and simulated solar irradiances mostly originates from the assumed or parameterized ice effective radius. [ABSTRACT FROM AUTHOR]

In this case study, measured solar irradiances above and below Arctic cirrus are compared to simulations of the European Centre for Medium-Range Weather Forecasts' Integrated Forecasting System (IFS) making use of offline runs of the operational ecRad radiation scheme. Independent of the solar irradiances, cirrus properties are derived from active remote sensing and used to evaluate the optical and microphysical parameterizations in ecRad. The data set was collected in the central Arctic over sea ice (81° - 90° North) with the High Altitude LOng range research aircraft (HALO) during a campaign in March and April 2022. HALO was equipped with broadband radiation and remote sensing instrumentation, including upward and downward-looking pyranometers (solar irradiance), a cloud radar, and a multi-wavelength water vapor differential absorption lidar. Flight legs above andbelow single-layer cirrus were performed. Measurements of solar irradiance are used to evaluate the ecRad radiation scheme in two case studies of optically thin and thick cirrus. The optically thin cirrus had amean transmissivity of 0.9, while the optically thick cirrus had a transmissivity of about 0.6. Different ice optics parameterizations optionally available within ecRad are tested to improve the match between simulation and measurements. Furthermore, the IFS predicted ice water content and ice effective radius were replaced by values retrieved with the radar and lidar. The choice of ice optics parameterizations does not significantly improve the model-measurement agreement. However, introducing the retrieved ice microphysical properties brings measured and modelled irradiances into closer agreement for the optical thin cirrus, while the optically thick cirrus caseis now simulated as too thick. From the comparison of the different ice optics parametrizations in the original and in the forced setup, it can be concluded that the ice water content forcasted by the IFS is realistic. The missmatch between observed and simulated irradiances mostly originates from the assumed or parameterized ice effective radius. [ABSTRACT FROM AUTHOR]

Background: Migraine and vestibular migraine are disorders associated with a heightened motion sensitivity that provoke symptoms of motion-induced nausea and motion sickness. VM affects (3% of adults in the USA and affects three-fold more women than men. Triptans (selective serotonin receptor agonists) relieve migraine pain but lack efficacy for vertigo. Murine models of photophobia and allodynia have used injections of calcitonin gene-related peptide (CGRP) or other migraine triggers, such as sodium nitroprusside (SNP), to induce migraine sensitivities in mice to touch and light. Yet, there is limited research on whether these triggers affect motion-induced nausea in mice, and whether migraine blockers can reduce these migraine symptoms. We hypothesized that systemic delivery of CGRP or SNP will increase motion sickness susceptibility and motion-induced nausea in mouse models, and that migraine blockers can block these changes induced by systemically delivered CGRP or SNP. Methods: We investigated two measures of motion sickness assessment [motion sickness index (MSI) scoring and motion-induced thermoregulation] after intraperitoneal injections of either CGRP or SNP in C57BL/6J mice. The drugs olcegepant, sumatriptan and rizatriptan were used to assess the efficacy of migraine blockers. Results: MSI measures were confounded by CGRP’s effect on gastric distress. However, analysis of tail vasodilatations as a surrogate for motion-induced nausea was robust for both migraine triggers. Only olcegepant treatment rescued tail vasodilatations. Conclusions: These preclinical findings support the use of small molecule CGRP receptor antagonists for the treatment of motion-induced nausea of migraine, and show that triptan therapeutics are ineffective against motion-induced nausea of migraine [ABSTRACT FROM AUTHOR]

The instrumentation of the High Altitude and Long Range (HALO) research aircraft is extended by the new Broadband AirCrAft RaDiometer Instrumentation (BACARDI) to quantify the radiative energy budget. Two sets of pyranometers and pyrgeometers are mounted to measure upward and downward solar (0.3-3 µm) and thermal-infrared (3-100 µm) irradiances. The radiometers are installed in a passively ventilated fairing to reduce the effects of the dynamic environment, e.g., fast changes of altitude and temperature. The remaining thermal effects range up to 20Wm-2 for the pyranometers and 10Wm-2 for the pyrgeometers; they are corrected using an new efficient method that is introduced in this paper. Using data collected by BACARDI during a night flight, the thermal offsets are parameterized by the rate of change of the radiometer sensor temperatures. Applying the sensor temperatures instead of ambient air temperature for the parameterization provides a linear correction function (200-600Wm-2 K-1 s), that depends on the mounting position of the radiometer on HALO. Furthermore, BACARDI measurements from the EUREC4A (Elucidating the role of clouds-circulation coupling in climate) field campaign are analyzed to characterize the performance of the radiometers and to evaluate all corrections applied in the data processing. Vertical profiles of irradiance measurements up to 10 km altitude show that the thermal offset correction limits the bias due to temperature changes to values below 10Wm-2. Measurements with BACARDI during horizontal, circular flight patterns in cloud-free conditions demonstrate that the common geometric attitude correction of the solar downward irradiance provides reliable measurements in this typical flight sections of EUREC4A, even without active stabilization of the radiometer. [ABSTRACT FROM AUTHOR]

The clouds in the Atlantic trade-wind region are known to have an important role in the global climate system. Acquiring a comprehensive characterization of these clouds based on observations is a challenge, but it is a necessary piece of information for the evaluation of their representation in models. An exploration of how the macrophysical and microphysical cloud properties and organization of the cloud field impact the large-scale cloud radiative forcing is presented here. Direct measurements of the cloud radiative effects from the Broadband AirCrAft RaDiometer Instrumentation (BACARDI) on board the High Altitude and LOng Range Research Aircraft (HALO) and cloud observations from the GOES-16 satellite during the Elucidating the role of clouds-circulation coupling in climate (EUREC4A) campaign provide evidence to demonstrate what drives the cloud radiative effects in shallow trade-wind clouds. We find that the solar and terrestrial radiative effects of these clouds are largely driven by their macrophysical properties (cloud fraction and a scene-averaged liquid water path). However, we also conclude that the microphysical properties, cloud top height and the organization of the cloud field demonstrate an increasing relevance in determining the cloud radiative effects as the cloud fraction increases. [ABSTRACT FROM AUTHOR]

As part of the EUREC4A field campaign, the German research aircraft HALO, configured as a cloud observatory, conducted 15 research flights in the trade wind region east of Barbados in January and February 2020. Narrative text, aircraft state data, and meta data describing HALO's operation during the campaign are provided. Each HALO research flight is segmented by time-stamp intervals into standard elements to aid the consistent analysis of the flight data. Photographs from HALO's cabin and animated satellite images synchronized with flight tracks are provided to visually document flight conditions. As a comprehensive product from the remote sensing observations, a multi-sensor cloud mask product is derived and quantifies the incidence of clouds observed during the flights. In addition, to lower the threshold for new users of HALO's data, a collection of use cases is compiled into an online book "How to EUREC4A", included as an asset with this paper. This online book provides easy access to most of EUREC4A's HALO data through an intake catalogue. [ABSTRACT FROM AUTHOR]