Despite its widespread influences on the atmosphere, the Madden‐Julian oscillation (MJO) remains poorly represented in state‐of‐the‐art general circulation models (GCMs). Motivated by recent findings ...that the horizontal advection of the mean low‐tropospheric moist static energy or moisture by the MJO winds plays a crucial role in the eastward propagation of the MJO, we investigate the relationship between lower tropospheric moisture patterns over the Indo‐Pacific and MJO eastward propagation in a suite of 23 GCM simulations. Model capability of reproducing the observed November–April mean lower tropospheric moisture pattern over the Indo‐Pacific, especially near the Maritime Continent (MC), is highly correlated with model skill in simulating MJO eastward propagation. In GCMs with difficulty capturing realistic MJO propagation, the amplitude of the mean low‐level moisture over the MC is greatly underestimated, leading to weak horizontal moisture gradients and thus discrepancies in moisture advection, significantly affecting MJO propagation. This study suggests that the mean lower tropospheric moisture pattern over the MC can serve as an important diagnostic metric for MJO propagation in climate models.
Key Points
Model skill of the Maritime Continent (MC) winter mean low‐level moisture pattern is highly correlated with MJO eastward propagation skill
The amplitude of MC mean low‐level moisture is greatly underestimated in poor MJO models, leading to discrepancies in moisture advection
The seasonal mean lower level moisture pattern over the MC is a useful diagnostic metric to evaluate MJO propagation in climate models
Dwellings built between 1945 and 1980 have the largest energy demand in the EU, which by 2009 represented 70% of the final energy use in buildings. A great portion of these dwellings have not been ...retrofitted and most of them were not built with any energy efficiency measures, since most of the energy regulations were implemented after the oil crisis in the 70s. To face this issue several actions were taken in the EU, among these, the implementation of Energy Performance Certification, which includes a Recommendation List of Measures (RLMs) to retrofit the property. The main objective of this study is to identify the weaknesses of the RLMs and to suggest changes to improve the quality and impact of this feature. The results indicate that to retrofit an existing building, the RLMs lack information for decision-making. The study suggests important barriers to overcome for achieving potential energy reductions in existing residential buildings, highlighting improvements to the recommendation content and its implementation.
This study investigates an exceptional Gulf of Mexico dry air outbreak triggered by Hurricane Ian and fueled by dry air originating from drought‐stricken mid‐latitudes under a high‐pressure system. ...The convergence of meteorological forces, combining cooler, dry air with a warmer, humid sea surface and strong winds, intensified latent and sensible heat exchanges, resulting in significant oceanic heat loss. Data from the 2022 Atlantic hurricane Saildrone mission and satellite flux analysis revealed that the outbreak's total turbulent heat fluxes peaked above 850 Wm−2, comparable to or even surpassing the hurricane’s impact. Argo float measurements recorded a 40‐m deepening of the mixed layer and a 1.4°C temperature decrease. In the tropical Atlantic, wind effects outweighed humidity in driving flux variability. Saildrone’s high‐frequency linewise measurements, distinct from satellite’s footprint averages, provide unique insights into wind variability under high wind conditions.
Plain Language Summary
Dry air outbreaks in the Gulf of Mexico are meteorological events marked by the influx of drier and often cooler air masses into the typically warm and humid Gulf region. These events occur mostly during the fall and winter months and are associated with atmospheric circulation patterns, particularly the transit of high‐pressure systems from the North American continent. This study highlights an exceptional dry air outbreak in late September 2022, triggered by Hurricane Ian and intensified by dry air originating from drought‐stricken mid‐latitudes, a condition sustained by a persistent high‐pressure system. The interaction between cold, dry air and warm, humid sea surface, coupled with strong winds, intensified the turbulent transfer of heat from the ocean to the atmosphere, resulting in significant ocean heat loss. Data from the 2022 Atlantic hurricane Saildrone mission and satellite flux analysis revealed that the outbreak’s total turbulent heat fluxes peaked above 850 Wm−2, comparable to or even surpassing the hurricane’s impact. Concurrently, the ocean’s surface layer deepened by about 40 m, and the temperature dropped by around 1.4°C. These findings hold substantial implications for understanding the Gulf's weather patterns and their impact on tropical storms, with the potential to influence both their intensity and trajectories.
Key Points
Hurricane Ian triggered a dry air outbreak, causing substantial turbulent heat loss (>850 Wm−2) and Gulf of Mexico surface cooling (∼1.4°C)
Winds, not air‐sea humidity, are a dominant contributor to turbulent heat flux in the tropical Atlantic warm water pool
Saildrone’s high‐frequency linewise data, differing from satellite’s footprint averages, offer unique insight into high wind variability
General aspects of zeolite acidity characterization Sandoval-Díaz, Luís-Ernesto; González-Amaya, Jhon-Alex; Trujillo, Carlos-Alexander
Microporous and mesoporous materials,
10/2015, Letnik:
215
Journal Article
Recenzirano
This paper describes the most used techniques in the determination of the acid property in zeolite materials. Two families of techniques, namely spectrometric (IR, NMR) and adsorption–desorption ...methods (calorimetry, TPD) are considered. Typical experimental conditions, schematics of equipment setup, and rules for molecular probe selection are shown. Selected experiments that make use of these methods are briefly discussed, and their most relevant results are presented. This review shows some of the possibilities that can be used to “measure” acidity in zeolites. It is also shown that the interpretation of such results could be deceiving in certain situations, especially because acidity and catalytic performance are not synonyms and acidity is inherently a relative term.
Display omitted
•Acidity is a relative property.•The nature of acid sites in zeolites can only be determined through the utilization of adequate probes.•Thermodesorption results are meaningless unless adequate mathematic models are used.•Acidity and catalytic performance are not synonyms.
Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these ...expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approaches such as scaffold analysis, similarity searching, and druggability analysis. We used polarization assays to confirm the CUG repeat binding in vitro for a number of candidate compounds, and went on to evaluate the biological activity of the two with the strongest affinity for CUG repeats (which we refer to as compounds 1-2 and 2-5) in DM1 mutant cells and Drosophila DM1 models with an impaired locomotion phenotype. In particular, 1-2 and 2-5 enhanced the levels of free MBNL1 in patient-derived myoblasts in vitro and greatly improved DM1 fly locomotion in climbing assays. This work provides new computational approaches for rational large-scale virtual screens of molecules that selectively recognize CUG structures. Moreover, it contributes valuable knowledge regarding two compounds with desirable biological activity in DM1 models.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Over 79 hands-on recipes for professional embedded Linux developers to optimize and boost their Yocto Project know-howAbout This BookOptimize your Yocto setup to speed up development and debug build ...issuesUse what is quickly becoming the standard embedded Linux product builder framework—the Yocto ProjectRecipe-based implementation of best practices to optimize your Linux systemWho This Book Is ForIf you are an embedded Linux developer with the basic knowledge of Yocto Project, this book is an ideal way to broaden your knowledge with recipes for embedded development.What You Will LearnOptimize your Yocto Project setup to speed up development and debug build issuesUse Docker containers to build Yocto Project-based systemsTake advantage of the user-friendly Toaster web interface to the Yocto Project build systemBuild and debug the Linux kernel and its device treesCustomize your root filesystem with already-supported and new Yocto packagesOptimize your production systems by reducing the size of both the Linux kernel and root filesystemsExplore the mechanisms to increase the root filesystem securityUnderstand the open source licensing requirements and how to comply with them when cohabiting with proprietary programsCreate recipes, and build and run applications in C, C++, Python, Node.js, and JavaIn DetailThe Yocto Project has become the de facto distribution build framework for reliable and robust embedded systems with a reduced time to market.You'll get started by working on a build system where you set up Yocto, create a build directory, and learn how to debug it. Then, you'll explore everything about the BSP layer, from creating a custom layer to debugging device tree issues. In addition to this, you'll learn how to add a new software layer, packages, data, scripts, and configuration files to your system. You will then cover topics based on application development, such as using the Software Development Kit and how to use the Yocto project in various development environments. Toward the end, you will learn how to debug, trace, and profile a running system. This second edition has been updated to include new content based on the latest Yocto release.Style and approachThis recipe-based book will guide you through all the development stages of an embedded Linux product design using the Yocto Project.
Abstract
The latitudinal location of the east Pacific Ocean intertropical convergence zone (ITCZ) changes on time scales of days to weeks during boreal spring. This study focuses on tropical ...near-surface dynamics in the days leading up to the two most frequent types of ITCZ events, nITCZ (Northern Hemisphere) and dITCZ (double). There is a rapid daily evolution of dynamical features on top of a slower, weekly evolution that occurs leading up to and after nITCZ and dITCZ events. Zonally elongated bands of anomalous cross-equatorial flow and off-equatorial convergence rapidly intensify and peak 1 day before or the day of these ITCZ events, followed 1 or 2 days later by a peak in near-equatorial zonal wind anomalies. In addition, there is a wide region north of the southeast Pacific subtropical high where anomalous northwesterlies strengthen prior to nITCZ events and southeasterlies strengthen before dITCZ events. Anomalous zonal and meridional near-surface momentum budgets reveal that the terms associated with Ekman balance are of first-order importance preceding nITCZ events, but that the meridional momentum advective terms are just as important before dITCZ events. Variations in cross-equatorial flow are promoted by the meridional pressure gradient force (PGF) prior to nITCZ events and the meridional advection of meridional momentum in addition to the meridional PGF before dITCZ events. Meanwhile, variations in near-equatorial easterlies are driven by the zonal PGF and the Coriolis force preceding nITCZ events and the zonal PGF, the Coriolis force, and the meridional advection of zonal momentum before dITCZ events.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Tropical intraseasonal variability, with the Madden‐Julian oscillation (MJO) as its most prominent mode, exerts extensive influences on global weather extremes. It is found that strong interannual ...variability of intraseasonal convection exists in the west Pacific (WP), in the form of years with strong eastward propagation (i.e., associated with the MJO) and years with strong westward propagation. Years with strong westward propagation on intraseasonal timescales are dominated by a westward propagating intraseasonal mode (WPIM), which is the second leading intraseasonal mode after the MJO over the tropical WP. Initiated over the central Pacific, the WPIM exhibits slow equatorial westward propagation (5 m/s) with a period of 25 days and a spatial scale of zonal wave number 3–4. Unlike the MJO, the WPIM lacks a significant tilt with height in specific humidity and vertical velocity. A strong anticorrelation is found between MJO and WPIM activity on interannual timescales over the WP. Budget analyses of the moist static energy suggest that both modes are driven by horizontal moist static energy advection and that substantial differences in winter mean large‐scale moisture and zonal winds largely define their distinct propagation behaviors. The WPIM is favored, while the MJO is suppressed when mean equatorial low‐level easterlies between 150°E and 160°W are enhanced and equatorial mean low‐level moisture is reduced near the Dateline and enhanced in the off‐equatorial WP (110°–150°E). While the WPIM bears resemblance to low‐frequency equatorial Rossby waves, a more detailed analysis must be conducted to affirm if they are the same phenomenon.
Key Points
Strong interannual variability of intraseasonal OLR exists in the tropical WP, dominated by the MJO and a westward propagating mode (WPIM)
MSE budgets show that the MJO and WPIM are driven by horizontal MSE advection and the seasonal distribution of low‐level moisture and zonal wind
Abstract
The intertropical convergence zone (ITCZ) is one of the most striking features of Earth’s climate system, often forming a narrow band of convection over many oceanic regions, especially in ...eastern ocean basins. It is not well understood why the ITCZ is so thin; however, a recent study highlighted that classical Ekman balance is not obeyed near the equator and nonlinear horizontal wind advection can localize ITCZ boundary layer vertical motion so that it becomes very narrow and intense. In this study, we use a similar model but with more realistic forcings from the Year of Tropical Convection (YOTC) reanalysis, focusing on the eastern Pacific Ocean ITCZ. The model is a zonally symmetric, slab (subcloud) boundary layer numerical model on the sphere, which can be considered the simplest “dry” model of the ITCZ. Due to the slab model’s simplicity, simulations are conducted at a range of resolutions, from 1° to 1 km. The slab model dynamical fields are in general agreement with the YOTC dynamical fields and precipitation estimates from the Tropical Rainfall Measuring Mission for one summer and two spring ITCZ cases. We find that Ekman balance is indeed violated within 10°–15° of the equator and nonlinear horizontal wind advection is crucial to understanding the preferential location, width, and intensity of the eastern Pacific ITCZ. Additionally, it appears that these boundary layer processes involved in ITCZ intensification and narrowing are dependent on model resolution such that present-day general circulation models likely cannot sufficiently resolve them.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The polyphagous shot hole borer (PSHB) is an invasive ambrosia beetle that forms a symbiosis with a new, as-yet-undescribed Fusarium sp., together causing Fusarium dieback on avocado and other host ...plants in California and Israel. In California, PSHB was first reported on black locust in 2003 but there were no records of fungal damage until 2012, when a Fusarium sp. was recovered from the tissues of several backyard avocado trees infested with PSHB in Los Angeles County. The aim of this study was to determine the plant host range of the beetle-fungus complex in two heavily infested botanical gardens in Los Angeles County. Of the 335 tree species observed, 207 (62%), representing 58 plant families, showed signs and symptoms consistent with attack by PSHB. The Fusarium sp. was recovered from 54% of the plant species attacked by PSHB, indicated by the presence of the Fusarium sp. at least at the site of the entry hole. Trees attacked by PSHB included 11 species of California natives, 13 agriculturally important species, and many common street trees. Survey results also revealed 19 tree species that function as reproductive hosts for PSHB. Additionally, approximately a quarter of all tree individuals planted along the streets of southern California belong to a species classified as a reproductive host. These data suggest the beetle-disease complex potentially may establish in a variety of plant communities locally and worldwide.
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