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The article focuses on National Defense Authorization Act for Fiscal Year 2020, the purpose of the U.S. Space Force (USSF) is to provide for freedom of operations in, and space domain for the U.S. and shall include combat and combat-support functions to enable prompt and sustained offensive and defensive space operations and joint operations in alldomains. Topics include the USSF serves to space commensurate with its importance to national security and the security of our allies and partners.

To evaluate the SEVIRI retrieval for aerosols above clouds presented in Part 1 of the companion paper, the algorithm is applied over the south-east Atlantic Ocean during the CLARIFY-2017 field campaign period. The first step of our analysis compares the retrieved aerosol and cloud properties against equivalent products from the MODIS MOD06ACAERO retrieval (Meyer et al., 2015). While the correlation between the two satellite retrievals of the above-cloud aerosol optical thickness (AOT) is good (R = 0.78), the AOT retrieved by SEVIRI is 20.3 % smaller than that obtained from the MODIS retrieval. This difference in AOT is attributed mainly to the more absorbing aerosol model assumed for the SEVIRI retrieval compared to MODIS. The underlying cloud optical thickness (COT) derived from the two satellites is in good agreement (R = 0.90). The cloud droplet effective radius (CER) retrieved by SEVIRI is consistently smaller than MODIS by 2.2 µ m, which is mainly caused by the use of different spectral bands of the satellite instruments. In the second part of our analysis, we compare the forecast water vapour profiles used for the SEVIRI atmospheric correction as well as the aforementioned aerosol and cloud products with in situ measurements made from the Facility for Airborne Atmospheric Measurements (FAAM) aircraft platform during the CLARIFY-2017 campaign. Around Ascension Island, the column water vapour used to correct the SEVIRI signal is overestimated by 3.1 mm in the forecast compared to that measured by dropsondes. However, the evidence suggests that the accuracy of the atmospheric correction improves closer to the African coast. Consistency is observed between the SEVIRI above-cloud AOT and in situ measurements (from cavity ring-down spectroscopy instruments) when the measured single-scattering albedo is close to that assumed in the retrieval algorithm. On the other hand, the satellite retrieval overestimates the AOT when the assumed aerosol model is not absorbing enough. Consistency is also found between the cloud properties retrieved by SEVIRI and the CER measured by a cloud droplet probe and the liquid water path derived from a microwave radiometer. Despite the instrumental limitations of the geostationary satellite, the consistency obtained between SEVIRI, MODIS and the aircraft measurements demonstrates the ability of the retrieval in providing additional information on the temporal evolution of the aerosol properties above clouds. [ABSTRACT FROM AUTHOR]

This article centres on John Alcock and Arthur Whitten Brown, two Mancunians who were the first people to fly the Atlantic non-stop, yet are largely neglected as a subject of acclaim or study and even the centenary of their historic flight from Newfoundland to Ireland went by virtually uncelebrated in Britain in 2019. Alcock died six months after their ground-breaking flight and Brown, an understated character, was not comfortable with fame, but their circumstances and disposition do not explain why they have been forgotten. This article will try to explain why by examining the coverage of three newspapers, one provincial and two national, through the lens of news values. [ABSTRACT FROM AUTHOR]

Long-haul low-cost carrier (LHLC) business models are generating considerable interest from the aviation practitioners and academics. Despite the high interest for the LHLC business model, only a few have compared the LHLC business model to a hybrid carrier business model and studied how airlines can compete with LHLCs. This paper analyses the differences of hybrid and long-haul low-cost carrier models and shows how Aer Lingus airlines has secured its dominant position in the Irish–US market. Product comparison with the help of in-depth interviews with key aviation practitioners as well as secondary data about the capacity and demand of the two carriers in question proves the differences between the two models. Porter five forces model provides an overview of the external competitive environment where the airlines in question operate. The research concluded that the hybrid and long-haul low-cost business model characteristics have many similarities, but also significant differences. It was also discovered that LHLC lack capacity and frequency, as well as feeder traffic, are very important elements for the transatlantic market. Robust route network including interline traffic and low operating cost, elements present in the hybrid airline business model, ensure profitability.

It has been suggested that the intraseasonal sea surface temperature (SST) variability in the tropical oceans can be amplified by the diurnal cycle of SST (dSST). Here, by analyzing the global tropical moored buoy array for the first time, we find that the intraseasonal SST variability is indeed amplified by the dSST in most of the tropical oceans, especially in the Indo‐Pacific warm pool, but weakened in the equatorial cold tongues of the Pacific and Atlantic Oceans. Such a divergent response is associated with the difference in atmosphere‐ocean interaction processes over these two regions. In the warm pool region, SST responds to the intraseasonal atmospheric variability, resulting in in‐phase intraseasonal fluctuations between SST and dSST that amplify the intraseasonal SST variability. However, in the cold tongue region, SST drives the atmospheric changes, which leads to out‐of‐phase intraseasonal fluctuations between SST and dSST and thus the inhibition of the intraseasonal SST variability. Plain Language Summary: The diurnal cycle is a fundamental timescale in the climate system, which has important nonlinear impacts on the variability on longer timescales. Previous studies have suggested that the diurnal cycle of sea surface temperature (SST) amplifies the SST variability on intraseasonal timescales of 20–90 days in the tropical region. By analyzing ocean temperature measurements from moored buoys located in the global tropical oceans, we find that the aforementioned amplification effect does exist in most of the tropical oceans, however, the diurnal cycle of SST weakens the intraseasonal SST variability in the equatorial eastern Pacific and Atlantic Oceans. Such contrasting results are associated with the different interaction processes between the atmosphere and the ocean over these regions. This is the first report of the inhibition effect, adding a new insight into the impact of the diurnal cycle of SST on intraseasonal SST variability. Key Points: The rectification of the intraseasonal sea surface temperature (SST) variability by the SST diurnal cycle is revealed by the global tropical moored buoy arrayThe intraseasonal SST variability is enhanced by the diurnal cycle in the Indo‐Pacific warm pool but weakened in the equatorial cold tonguesThese divergent responses are associated with the difference in atmosphere‐ocean interaction processes over these two regions [ABSTRACT FROM AUTHOR]

The low magnetic field in the South Atlantic Anomaly (SAA) zone facilitates the entrance of high-energy particles from the magnetosphere. When particles that are drifting in closed orbits around the Earth reach the SAA zone, they can be quasi-trapped instead of being trapped in a stable way or precipitating. The effects over the total column ozone (TCO), NOx (= NO + NO2) and ozone profiles in the SAA zone during and after two intense geomagnetic storms that occurred during solar cycle 23 are analyzed in this work. The two periods occurred on November 20, 2003, and on November 08, 2004, during spring in the South American sector. Data of the Total Column Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet (SBUV) Merged Ozone Data and Upper Atmosphere Research Satellite (UARS-HALOE) are used. Three stations located in the SAA zone are chosen for the analysis with TOMS and SBUV data. During both storms, a statistically significant TOC decrease is observed. In the 2003 storm, the decrease reached values between −4.4 % and −6.0% one week after the day of the minimum value of the disturbance storm time (Dst) index, and in the 2004 storm the decrease is observed on November 17, with a value of the order of −4.0% over the three stations. In the case of ozone profiles from SBUV data, between 0.639 hPa and 101.3 hPa, a significant increase at middle stratospheric heights during both storms is detected. The following days also show significant decreases in the middle and lower stratosphere for the 2003 storm. On the other hand, from UARS-HALOE data, we observe that for both storms, the profiles of the relative difference of NOx show significant increases between 25 and 40 km, but ozone profiles do not present significant changes for the analyzed storms [ABSTRACT FROM AUTHOR]

This work assesses the value of expendable bathythermograph (XBT) and Argo profiling float observations to monitor the Atlantic Ocean boundary current systems (BCS), meridional overturning circulation (MOC), and meridional heat transport (MHT). Data from six XBT transects and available Argo floats in the Atlantic Ocean for the period from 2000 to 2018 are used to estimate the structure and variability of the BCS, MOC, and MHT, taking into account different temporal and spatial mapping strategies. The comparison of Argo data density along these six XBT transects shows that Argo observations outnumber XBT observations only above mapping scales of 30 days and 3° boxes. The comparison of Argo and XBT data for the Brazil Current and Gulf Stream shows that Argo cannot reproduce the structure and variability of these currents, as it lacks sufficient resolution to resolve the gradients across these narrow jets. For the MHT and MOC, Argo estimates are similar to those produced by XBTs at a coarse mapping resolution of 5° and 30 days. However, at such a coarse resolution the root-mean-square errors calculated for both XBT and Argo estimates relative to a high-resolution baseline are higher than 3 Sv (1 Sv ≡ 106 m3 s−1) and 0.25 PW for the MOC and MHT, respectively, accounting for about 25%–30% of their mean values due to the smoothing of eddy variability along the transects. A key result of this study is that using Argo and XBT data jointly, rather than separately, improves the estimates of MHT, MOC, and BCS. [ABSTRACT FROM AUTHOR]

In this study we compare measured and simulated O4 absorptions for conditions of extremely low aerosol optical depth (between 0.034 to 0.056 at 360 nm) on one day during a ship cruise in the tropical Atlantic. For such conditions, the uncertainties related to imperfect knowledge of aerosol properties don't significantly affect the comparison results. We find that the simulations underestimate the measurements by 15 % to 20 %. Even for simulations without any aerosols the measured O4 absorptions are still systematically higher than the simulation results. The observed discrepancies can not be explained by uncertainties of the measurements and simulations and thus indicate a fundamental inconsistency between simulations and measurements. [ABSTRACT FROM AUTHOR]

Under the Trump administration, a transatlantic trade conflict has been escalating step by step. First, it was about tariffs on steel and aluminium, then about retaliation for the French digital tax, which is suspended until the end of the year. Most recently, the US administration threatened the European Union with tariffs on cars and car parts because of Canadian seafood being subject to lower import duties. As simulations with NiGEM show, a further escalation of the transatlantic trade conflict has the potential to slow down economic growth significantly in the countries involved. This is a considerable risk given the fact that the countries have to cope with the enormous negative effects of the pandemic shock. Furthermore, the damage caused by the trade conflict depends on the extent to which the affected countries use fiscal policy to stabilise their economies. [ABSTRACT FROM AUTHOR]

This paper examines the effects of competition driven by low-cost airlines and high-speed trains on long-haul connecting routings. We use passenger and fare data for 2010–2017 on transatlantic routings with a stopover in large European hub airports. Competition from low-cost airlines on the short segments of transatlantic routings reduces the number of connecting passengers channeled by hubbing airlines, who have to pay higher fares. In contrast, high-speed rail services are not found to lead to a reduction in the number of connecting passengers or to an increase in the price they have to pay. • Competition by LCC and HSR on transatlantic connecting routes is examined. • Competition from LCC on short segments lead to less connecting passengers. • Competition from LCC on short segments lead to higher fares. • Airline competition in the long segments does not harm connecting travelers. • Competition from HSR on short segments does not harm connecting travelers. [ABSTRACT FROM AUTHOR]

According to historical records of transatlantic slavery, traders forcibly deported an estimated 12.5 million people from ports along the Atlantic coastline of Africa between the 16th and 19th centuries, with global impacts reaching to the present day, more than a century and a half after slavery's abolition. Such records have fueled a broad understanding of the forced migration from Africa to the Americas yet remain underexplored in concert with genetic data. Here, we analyzed genotype array data from 50,281 research participants, which—combined with historical shipping documents—illustrate that the current genetic landscape of the Americas is largely concordant with expectations derived from documentation of slave voyages. For instance, genetic connections between people in slave trading regions of Africa and disembarkation regions of the Americas generally mirror the proportion of individuals forcibly moved between those regions. While some discordances can be explained by additional records of deportations within the Americas, other discordances yield insights into variable survival rates and timing of arrival of enslaved people from specific regions of Africa. Furthermore, the greater contribution of African women to the gene pool compared to African men varies across the Americas, consistent with literature documenting regional differences in slavery practices. This investigation of the transatlantic slave trade, which is broad in scope in terms of both datasets and analyses, establishes genetic links between individuals in the Americas and populations across Atlantic Africa, yielding a more comprehensive understanding of the African roots of peoples of the Americas. [ABSTRACT FROM AUTHOR]

Market concentration in the airline industry, its measurement, causes, and consequences, has been a long-standing issue with airline representatives, public authorities, interest groups, and academics alike. This paper extends research on assessing market concentration in the airline industry by incorporating high-speed rail (HSR) services and connecting flights as travel alternatives to nonstop flights. Our methodology includes a connection builder calibrated with booking data, a Quality of Service Index (QSI) model for quality-weighting of travel alternatives, and the Herfindahl-Hirschman Index (HHI). We calculate HHI for origin and destination (O&D) city pairs originating in Germany on route and city level and provide aggregate metrics for all directional O&Ds worldwide ex Germany and across different destination categories applying a gravity model for size-weighting of O&Ds. Our findings support concerns about Lufthansa Group becoming more dominant in the German air transport market after the collapse of Air Berlin. [ABSTRACT FROM AUTHOR]

We prove that nonlocal minimal graphs in the plane exhibit generically stickiness effects and boundary discontinuities. More precisely, we show that if a nonlocal minimal graph in a slab is continuous up to the boundary, then arbitrarily small perturbations of the far-away data produce boundary discontinuities. Hence, either a nonlocal minimal graph is discontinuous at the boundary, or a small perturbation of the prescribed conditions produces boundary discontinuities. The proof relies on a sliding method combined with a fine boundary regularity analysis, based on a discontinuity/smoothness alternative. Namely, we establish that nonlocal minimal graphs are either discontinuous at the boundary or their derivative is Hölder continuous up to the boundary. In this spirit, we prove that the boundary regularity of nonlocal minimal graphs in the plane "jumps" from discontinuous to C 1 , γ , with no intermediate possibilities allowed. In particular, we deduce that the nonlocal curvature equation is always satisfied up to the boundary. As an interesting byproduct of our analysis, one obtains a detailed understanding of the "switch" between the regime of continuous (and hence differentiable) nonlocal minimal graphs to that of discontinuous (and hence with differentiable inverse) ones. [ABSTRACT FROM AUTHOR]

In this article, I explore the banalities of qualitative work flirting with some of the premises of non-representation theories' (NRT) thinking style. More specifically, I interrogate the usefulness of thinking with the mundane to explore the kinds of opportunities that could be afforded to language and transcultural communication if we repositioned qualitative work as a more-thanhuman affair. Drawing from experiences while conducting fieldwork onboard transatlantic flights, I discuss the implications of accounting for banalities and their embodiment within a flat ontology perspective. I conclude with a few remarks on criticality and qualitative research striving to present --as opposed to represent--elements in the fieldwork otherwise discarded as irrelevant, but that might be particularly revealing of what shapes a researcher's logic and what the researcher brings to bear as social phenomena, particularly in language and (as) communication. [ABSTRACT FROM AUTHOR]

The article discusses the XPrize Foundation's continuing support of innovative projects that solve problems in the world as of 2020. Topics covered include the foundation's history, its Progressive Automotive XPrize (PAIXP) to increase fuel-efficient vehicle awareness, its Wendy Schmidt Ocean Health XPrize for measuring ocean chemistry, and its Global Learning XPrize for self-learning software for children. Also noted is the unclaimed Google Lunar XPrize for landing and operating a Moon rover. INSET: THE STORY OF HOW THE XPRIZE WAS BORN.

While previous studies consistently suggest that North Atlantic Deep Water (NADW) was shallower at the Last Glacial Maximum (LGM) than at pre‐industrial, its strength is still controversial. Here, using a series of LGM experiments, we show that proxy records are consistent with a shallower and ∼50% weaker NADW, associated with a ∼3° equatorward shift of the sea ice edge and convection sites in the Norwegian Sea. A shoaling and weakening of NADW further allow penetration of Antarctic Bottom Water in the North Atlantic, despite Antarctic Bottom Water transport being reduced by ∼40%. While the Deep Western Boundary Current in the northwest Atlantic weakens with NADW, the mid‐depth southward flow on the east side of the north Mid‐Atlantic Ridge strengthens, consistent with paleorecords. This northeast Atlantic intensification is due to a change in density gradients: a weaker AMOC reduces the transport of equatorial waters to the northeast Atlantic, thus weakening the North Atlantic zonal density gradient. The resultant globally weaker oceanic circulation at the LGM would have contributed to an increase in oceanic carbon content and thus a decrease in atmospheric CO 2 concentration. Key Points: As the AMOC weakens, Nordic Sea sea ice and convection sites shift equatorward and the Deep Western Boundary Current weakens proportionallyAs the AMOC weakens, the southward flow on the eastern side of the Mid‐Atlantic Ridge strengthens by up to 100%Proxy records are consistent with both weaker NADW and AABW at the Last Glacial Maximum [ABSTRACT FROM AUTHOR]