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This study reexamines cloud and precipitation variability associated with the Madden‐Julian Oscillation (MJO) over the Maritime Continent (MC), mainly using data acquired in 1998–2013 by the Tropical Rainfall Measuring Mission satellite. Infrared data indicated uniform, moderately deep stratiform cloud cover over the MC during MJO active phases, suggesting that an apparent MJO bypass of Borneo and New Guinea, observed in the brightness temperature anomaly distribution, was an artifact of climatologically low average brightness temperatures above the islands. Although previous satellite precipitation products indicated negligible anomalies over Borneo during MJO active phases, we identified positive precipitation anomalies in precipitation radar data and other recent satellite products. We hypothesize that previous satellite precipitation data products underestimated stratiform precipitation over Borneo during MJO active phases because ice‐particle scattering was weak. This is consistent with the moderately deep stratiform cloud layer identified from infrared data. Plain Language Summary In this study, we investigated cloud and precipitation over the Maritime Continent, the region comprising thousands of islands between the Indian and Pacific Oceans, associated with a tropical intraseasonal oscillation propagating eastward along the equator. Previous studies reported that clouds associated with this oscillation apparently bypassed Borneo and New Guinea. Our analysis showed that the climatologically averaged cloud height over Borneo and New Guinea reached higher altitudes than in the surrounding areas. Previous satellite precipitation data products did not indicate notable rainfall variations over Borneo during active phases. However, analyzing more recent data from satellite instruments, including from a precipitation radar, we identified positive precipitation anomalies. This suggests that previous satellite data products underestimated widespread weak precipitation over Borneo during the active phases of the tropical intraseasonal oscillation, probably because scattering by ice particles was weak. Key Points Bypass of the Maritime Continent by the Madden‐Julian Oscillation seen in brightness temperature anomaly is a climatology‐induced artifact Previous satellite precipitation products underestimated Madden‐Julian Oscillation precipitation anomalies over the Maritime Continent The conventional understanding of processes governing cloud and precipitation variability over the Maritime Continent must be updated

We review lattice results related to pion, kaon, D-meson, B-meson, and nucleon physics with the aim of making them easily accessible to the nuclear and particle physics communities. More specifically, we report on the determination of the light-quark masses, the form factor f+(0) arising in the semileptonic K→π transition at zero momentum transfer, as well as the decay constant ratio fK/fπ and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)L×SU(2)R and SU(3)L×SU(3)R Chiral Perturbation Theory. We review the determination of the BK parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. For the heavy-quark sector, we provide results for mc and mb as well as those for D- and B-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. We review the status of lattice determinations of the strong coupling constant αs. Finally, in this review we have added a new section reviewing results for nucleon matrix elements of the axial, scalar and tensor bilinears, both isovector and flavor diagonal.

We review lattice results related to pion, kaon, D - and B -meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor f + ( 0 ) , arising in the semileptonic K → π transition at zero momentum transfer, as well as the decay constant ratio f K / f π and its consequences for the CKM matrix elements V u s and V u d . Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of S U ( 2 ) L × S U ( 2 ) R and S U ( 3 ) L × S U ( 3 ) R Chiral Perturbation Theory. We review the determination of the B K parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m c and m b (also new compared to the previous review), as well as those for D - and B -meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α s .

We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor \\[f_+(0)\\], arising in the semileptonic \\[K \\] transition at zero momentum transfer, as well as the decay constant ratio \\[f_K/f_ \\] and its consequences for the CKM matrix elements \\[V_us\\] and \\[V_ud\\]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of \\[SU(2)_L SU(2)_R\\] and \\[SU(3)_L SU(3)_R\\] Chiral Perturbation Theory. We review the determination of the \\[B_K\\] parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for \\[m_c\\] and \\[m_b\\] (also new compared to the previous review), as well as those for D- and B-meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant \\[ _s\\].

Ocean circulation around the Antarctic coastal margins plays a critical role in heat delivery to Antarctica, melting ice shelves. However, until recently, satellite‐based sea‐level observations have been limited by the presence of sea ice. With improved algorithms, it is now possible to monitor sea‐level fluctuations over most of the Southern Ocean, including sea ice‐covered areas. We identified several clockwise gyres along East Antarctic coastal margins in satellite‐derived dynamic ocean topography (DOT). Singular value decomposition analyses revealed that the coastal DOT deepening and anomalous clockwise circulation consistently occur during the positive phase of the southern annular mode (SAM), which is associated with negative wind stress curl anomalies. Shifting of the SAM to a more positive phase since the 20th century and its expected continuation into the coming century could lead to enhanced clockwise gyres along East Antarctica, contributing to increased poleward ocean heat transport. Plain Language Summary The Southern Ocean melts the Antarctic ice sheet. The poleward ocean heat, which controls ice‐ocean interactions, is transported from offshore to coastal margins across the shelf break by ocean circulation. Satellite observations are powerful for monitoring global sea‐level distribution which is closely related to ocean circulation; however, this approach is difficult to apply to polar regions with sea ice. This limitation has been addressed through the development of improved satellite algorithms, enabling monitoring in these regions. In this study, we utilized improved satellite sea‐level data to investigate the relationship between sea‐level variation and atmospheric circulation, with a focus on East Antarctic regions. Using analyses to find interlocking patterns in ocean and atmospheric variables, we found that several clockwise gyres form along the East Antarctic coastal margins along with deepening coastal sea levels during the positive phase of the Southern Annular Mode, the leading mode of the Southern Hemisphere atmospheric circulation. The negative wind stress curl tendency associated with the SAM positive phase is responsible for strengthening the regional ocean gyres. The continuous shift of the SAM to a positive phase, both in the past and near future, is expected to enhance these gyres and increase poleward ocean heat transport. Key Points Variability of the ocean circulation along East Antarctica is investigated using satellite radar altimetry Clockwise ocean circulation varies in response to the negative wind stress curl, which depends on the Southern Annular Mode Expected trend toward the positive phase of SAM will leads to enhanced poleward ocean heat transport in the East Antarctic coastal area

The Antarctic continental margin supplies the densest bottom water to the global abyss. From the late twentieth century, an acceleration in the long-term freshening of Antarctic Bottom Waters (AABW) has been detected in the Australian-Antarctic Basin. Our latest hydrographic observations reveal that, in the late 2010s, the freshening trend has reversed broadly over the continental slope. Near-bottom salinities in 2018–2019 were higher than during 2011–2015. Along 170° E, the salinity increase between 2011 and 2018 was greater than that observed in the west. The layer thickness of the densest AABW increased during the 2010s, suggesting that the Ross Sea Bottom Water intensification was a major source of the salinity increase. Freshwater content on the continental slope decreased at a rate of 58 ± 37 Gt/a in the near-bottom layer. The decadal change is very likely due to changes in Ross Sea shelf water attributable to a decrease in meltwater from West Antarctic ice shelves for the corresponding period.

The search for water on Mars has long been a theme of intense exploration, as it represents a means of addressing Mars’ current climate as well as its evolution in the recent and more distant past. Since the 1970s, several missions have carried instruments to track water in the atmosphere, leading to the conceptualization of a water cycle on Mars characterized by intense seasonal variability in water vapor abundance across the planet. After Mariner 9, Viking, Phobos 2 and Mars Global Surveyor, Mars Express has become the fifth orbiter capable of detecting water vapour, with unique features: measurements by several instruments, each probing a distinct wavelength region from near-infrared to thermal infrared, altitude-dependent profiling of water thanks to solar occultation, and observation in the exosphere of its by-product, hydrogen atoms, which can escape into space, depriving Mars of its primordial water reservoir. Thanks to Mars Express, a new vision of Mars’ water cycle and escape processes has emerged. The achievements of Mars Express, as well as the legacy of other missions, which established the foundations of our understanding of Mars’ water cycle are presented in this article.

Here we present water vapor vertical profiles observed with the ExoMars Trace Gas Orbiter/Nadir and Occultation for MArs Discovery instrument during the perihelion and Southern summer solstice season (LS = 240°–300°) in three consecutive Martian Years 34, 35, and 36. We show the detailed latitudinal distribution of H2O at tangent altitudes from 10 to 120 km, revealing a vertical plume at 60°S–50°S injecting H2O upward, reaching abundance of about 50 ppmv at 100 km. We have observed this event repeatedly in the three Martian years analyzed, appearing at LS = 260°–280° and showing inter‐annual variations in the magnitude and timing due to long term effects of the Martian Year 34 Global Dust Storm. We provide a rough estimate of projected hydrogen escape of 3.2 × 109 cm−2 s−1 associated to these plumes, adding further evidence of the key role played by the perihelion season in the long term evolution of the planet's climate. Plain Language Summary Studying the vertical distribution of the Martian atmosphere is crucial to understand what happened to the water presumably present in larger abundance on ancient Mars. We have analyzed the vertical profiles of three Martian Years during the Southern summer, revealing a strong vertical transport of water vapor to the upper atmosphere. This seasonal phenomenon seems to be repeated annually, although with variations in the location and time of the year. Our estimation of the associated upward hydrogen flux represents an important loss which could have contributed to the escape of water to space for at least the period in which Mars had its present orbital inclination. Key Points Latitudinal distributions of water vapor up to 120 km are analyzed in detail using Nadir and Occultation for MArs Discovery (NOMAD) observations with an improved retrieval scheme Water vapor injection during the perihelion localized around 50°–60°S in three consecutive Martian years Martian year 34 Global Dust Storm may have affected the driving mechanisms of the plume, delaying its appearance and reducing its magnitude

Atmospheric methane (CH4) increased from ~900 ppb (parts per billion, or nanomoles per mole of dry air) in 1900 to ~1800 ppb in 2010 at a rate unprecedented in any observational records. However, the contributions of the various methane sources and sinks to the CH4 increase are poorly understood. Here we use initial emissions from bottom-up inventories for anthropogenic sources, emissions from wetlands and rice paddies simulated by a~terrestrial biogeochemical model, and an atmospheric general circulation model (AGCM)-based chemistry-transport model (i.e. ACTM) to simulate atmospheric CH4 concentrations for 1910–2010. The ACTM simulations are compared with the CH4 concentration records reconstructed from Antarctic and Arctic ice cores and firn air samples, and from direct measurements since the 1980s at multiple sites around the globe. The differences between ACTM simulations and observed CH4 concentrations are minimized to optimize the global total emissions using a mass balance calculation. During 1910–2010, the global total CH4 emission doubled from ~290 to ~580 Tg yr−1. Compared to optimized emission, the bottom-up emission data set underestimates the rate of change of global total CH4 emissions by ~30% during the high growth period of 1940–1990, while it overestimates by ~380% during the low growth period of 1990–2010. Further, using the CH4 stable carbon isotopic data (δ13C), we attribute the emission increase during 1940–1990 primarily to enhancement of biomass burning. The total lifetime of CH4 shortened from 9.4 yr during 1910–1919 to 9 yr during 2000–2009 by the combined effect of the increasing abundance of atomic chlorine radicals (Cl) and increases in average air temperature. We show that changes of CH4 loss rate due to increased tropospheric air temperature and CH4 loss due to Cl in the stratosphere are important sources of uncertainty to more accurately estimate the global CH4 budget from δ13C observations.

The DsTau(NA65) experiment at CERN was proposed to measure an inclusive differential cross-section of D s production with decay to tau lepton and tau neutrino in p – A interactions. The DsTau detector is based on the nuclear emulsion technique, which provides excellent spatial resolution for detecting short-lived particles like charmed hadrons. This paper presents the first results of the analysis of the pilot-run (2018 run) data and reports the accuracy of the proton interaction vertex reconstruction. High precision in vertex reconstruction enables detailed measurement of proton interactions, even in environments with high track density. The measured data has been compared with several Monte Carlo event generators in terms of multiplicity and angular distribution of charged particles. The multiplicity distribution obtained in p–W interactions is tested for KNO-G scaling and is found to be nearly consistent. The interaction length of protons in tungsten is measured to be 93.7 ± 2.6 mm . The results presented in this study can be used to validate event generators of p – A interactions.