Miracle-dz/UniFAR-FTUs huggingface dataset:
The Role of Moisture-Convection Feedbacks in Simulating the Madden-Julian Oscillation

AbstractThe sensitivity of a simulated Madden–Julian oscillation (MJO) was investigated in the NCAR Community Atmosphere Model 3.1 with the relaxed Arakawa–Schubert convection scheme by analyzing the model’s response to varying the strength of two moisture sensitivity parameters. A higher value of either the minimum entrainment rate or rain evaporation fraction results in increased intraseasonal variability, a more coherent MJO, and enhanced moisture–convection feedbacks in the model. Changes to the mean state are inconsistent between the two methods. Increasing the minimum entrainment leads to a cooler and drier troposphere, whereas increasing the rain evaporation fraction causes warming and moistening. These results suggest that no straightforward correspondence exists between the MJO and the mean humidity, contrary to previous studies.Analysis of the mean column-integrated and normalized moist static energy (MSE) budget reveals a substantial reduction of gross moist stability (GMS) for increased minimu.
A simple analytical approximation to the temperature structure in subduction zones

SUMMARY A simple model is employed to find scaling relations between key features of the temperature structure of subduction zones and subduction zone parameters. Flow in the wedge of mantle between the slab and the overriding plate is approximated by the corner flow of a Newtonian viscous fluid. The flow maintains an advective boundary layer on top of the slab that controls the temperature at the interface between the slab and the wedge. This temperature, the maximum temperature in the wedge above the slab, and the thickness of the advective boundary layer, all depend on a single dimensionless distance, Vrδ2/κ, where V is the speed of plate convergence, r is distance from the corner of the wedge, δ is the dip of the slab and κ is thermal diffusivity. The observation that volcanic fronts at island arcs lie above places where the slab reaches a depth that correlates negatively with convergence rate and slab dip suggests that the thermal structure of subduction zones may be described by the simple scaling developed here, and that the locations of the arcs are controlled by a strongly temperature-dependent process taking place in the wedge.
The development of a new dust uplift scheme in the Met Office Unified Model™

Aeolian mineral dust aerosol is an important consideration in the Earth's radiation budget as well as a source of nutrients to oceanic and land biota. The modelling of aeolian mineral dust has been improving consistently despite the relatively sparse observations to constrain them. This study documents the development of a new dust emissions scheme in the Met Office Unified Model™ (MetUM) based on the Dust Entrainment and Deposition (DEAD) module. Four separate case studies are used to test and constrain the model output. Initial testing was undertaken on a large dust event over North Africa in March 2006 with the model constrained using AERONET data. The second case study involved testing the capability of the model to represent dust events in the Middle East without being re‐tuned from the March 2006 case in the Sahara. While the model is unable to capture some of the daytime variation in AERONET AOD there is good agreement between the model and observed dust events. In the final two case studies new observations from in situ aircraft data during the Dust Outflow and Deposition to the Ocean (DODO) campaigns in February and August 2006 were used. These recent observations provided further data on dust size distributions and vertical profiles to constrain the model. The modelled DODO cases were also compared to AERONET data to make sure the radiative properties of the dust were comparable to observations. Copyright © 2009 Royal Meteorological Society and Crown Copyright
Bearing Capacity of Strip Footing on Sand Slopes Reinforced with Geotextile and Soil Nails

This paper presents the results of laboratory model tests on the behavior of a strip footing supported by a single geotextile layer and by a row of soil nails in a sandy slope. A comparison between bearing capacity improvements in the two cases were made and analyzed. Parameters varied include depth of the reinforcing layer, edge distance of the footing , location of soil nail row, and location of the footing relative to the slope crest. Bearing capacity of non-stabilized cases were initially determined and then compared with those of stabilized slopes. Results indicate that stabilized earth slope using a single geotextile layer or a row of soil nails significantly improves bearing capacity of strip footing. This improvement in bearing capacity increases as soil nail spacing decreases. Overall improvement is significantly better when using a single geotextile layer to stabilize earth slope than using a row of soil nails.
A weak link in metabolism : the metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis

Collagen is the protein that characterizes the animal world, as it is the material that allows multicellular fl exibility. It appeared with the origin of animal life in the Precambrian explosion (Aouacheria et al. 2006) and its history thus spans the same time period as that of animals, around 580 million years (Li et al. 1998). It is the most abundant protein in the human body and constitutes more than a quarter of the total protein (Waterlow 2006). The high content of glycine in collagen (one-third of the amino acid residues) implies an important requirement for the availability of this amino acid to support a healthy turnover of collagen, high enough to avoid problems of accumulation of undesirable chemical modifi cations (glycation and others), as a protein-defi cient diet induces decreased turnover of protein, especially collagen (Gibson et al. 2002). Renewal of collagen is not usually regarded as a problem, not only because collagen turnover was long believed to be very slow, but also because glycine is conventionally classifi ed as a non-essential amino acid, as it can be synthesized from serine in the reaction catalysed by glycine hydroxymethyltransferase (EC 2.1.2.1). However, clinical and nutritional studies during the past twenty years indicate that the amount of glycine available in humans is not enough to meet metabolic needs and that a dietary supplement is appropriate (Jackson et al. 1987; Jackson 1991; Persaud et al. 1996; Li et al. 2001; Brawley et al. 2003; Waterlow 2006). According to these authors, therefore, glycine should be considered a conditionally essential amino acid. These observations are puzzling, however, because the existence of a pathway to synthesize glycine confl icts with the idea that there could be a glycine defi ciency suffi ciently large to need a specifi c dietary supplement, and because it is thought
A method for delineating and estimating rainfall fields

A geostatistical model has been defined to deal with intermittent rainfall fields. The intermittency is represented by a binary random function, while, inside the rainy areas, the rainfall variability is rendered by an intrinsic random function. A rain gage data set from the Cevennes region (France) is used to infer the model. The inner variability is independent of the intermittency, thereby allowing a simple estimation relying on the separate kriging of these two components. Comparison of the rainfall assessments made by a classic global kriging and the proposed method shows its clear superiority for delineating and estimating rainfall fields.
Remote‐sensing magnetospheric dynamics with riometers: Observation and theory

[1] The importance of monitoring particle injection into the inner magnetosphere from the plasma sheet is exceeded perhaps only by its difficulty. The recent progress in using ground-based riometer data [e.g., Spanswick et al., 2007] to detect by proxy particle injection has raised much hope that this important aspect of substorms can be more consistently monitored. In this paper we develop a theoretical model for explaining the observed dispersionless injection events reported by Spanswick et al. The substorm event on 3 October 1998 is analyzed to give the empirical context for riometer responses during a typical substorm. Our simulation shows that riometer electrons produce a clean and strong signal that can be uniquely and easily related to magnetic field dipolarization that normally gives rise to injection.
Evolution of the Lefroy and Cowan palaeodrainage channels, Western Australia

A dendritic system of palaeodrainage channels is a prominent feature of the Yilgarn Craton of Western Australia. The history of the Cowan and Lefroy palaeodrainage channels described herein is typical of the mid‐lower reaches of these features. Incision of the palaeodrainage system occurred during Jurassic times. Reversal of the Cowan palaeodrainage channel occurred prior to Jurassic deposition in the Bremer Basin, resulting in the Cowan palaeodrainage channel flowing south to the Bremer Basin and the Lefroy palaeodrainage channel flowing east to the Eucla Basin. Earliest preserved strata consist of the Early to Middle Eocene non‐marine Hampton Sandstone and Pidinga Formation in the Lefroy palaeodrainage channel, and the Werillup Formation in the Cowan palaeodrainage channel. Subsequently, two transgressive sequences (Tortachilla and Aldinga transgressions) were deposited. During the Tortachilla transgression, estuarine‐deltaic facies of the Pidinga Formation and Hampton Sandstone were deposited in the Le.
Statistical tests for a correlation between decadal variation in June precipitation in China and sunspot number

[1] Six different statistical methods (i.e., correlation, difference, prominent period, variance contribution, scale-averaged spectrum, and cross spectrum) are used to test for regional differences in the relationship between the 11 year sunspot cycle and June precipitation in China during the 20th century. In the Huaihe River basin (HRB) of central China, located at the marginal region of the East Asian summer monsoon (EASM), there exists a reliable positive-correlation relationship between the 11 year sunspot cycle and June precipitation; whereas, possible negative and very weak positive correlations in the south of the middle–lower Yangtze River Region and the HeTao Basin (HTB), located in the interior of the EASM and the westerlies, respectively. The reasons for these regional differences are investigated, revealing that the marginal region of EASM may be more sensitive to solar forcing than is its interior, which results in the HRB becoming the most susceptible (strongest correlation) region. That is to say, in June during the high sunspot number (SSN) years, the influence of the EASM is significantly greater and more to the north than that in June during the low SSN years, causing the HRB to be mainly influenced by the EASM (westerlies) in June during the high (low) SSN years. The northward expansion of the June EASM probably resulted from enhancement of the low-level southwesterly monsoon flow over the northern tropical Indian Ocean, combined with an expansion of the western Pacific subtropical high at times of high SSN.
EVALUATION OF IN-SITU SATURATED HYDRAULIC CONDUCTIVITY IN A COASTAL HUMID TROPICAL WETLAND

ABSTRACT Measurement of groundwater-stream interactions is increasingly recognised as important to understand hydrological behaviour of wetlands. Hydraulic conductivity (K) of saturated soil is an important parameter in modelling the hydrological processes in wetlands. The present study aims at estimating the hydraulic conductivity of the coastal humid tropical wetland near National Institute of Technology Karnataka (NITK) Surathkal, Mangalore, India. The paper describes the technique and method used to estimate the hydraulic conductivity of the coastal humid tropical wetlands. Standard measurement techniques are often available, but feasible only in small fields, in areas with easy access, or on laboratory samples of substrata. A technique to obtain the estimates of hydraulic conductivity has been used by installing four Piezometers of 2.5 cm diameter at three different average depths (−45, −70 and −95 cm) of 15 cm screen opening and another (at -70 cm) of 30 cm screen opening within a meter depth of strata. Water level recovery measurements were made in these Piezometers and were found consistent with respect to time of recovery and show the correlation coefficient, R2 in between 0.9289 to 0.9955. Based on the best fit line (regression equation), the hydraulic conductivity of the wetland were computed for each site and the K values were found to be in the range of 3.1434×10 5cm/s to 36.07×10 5cm/s in the study area. The hydraulic conductivity as estimated was found to be varied over several orders of magnitude in each of the compartments but the deeper wetland soil was clearly the most permeable due to high sand content in the study area. It has been also observed that, K values at top and middle substrata were of same order in each site and then increased with increasing soil depth from middle to bottom substrata.
The Upper-Oceanic Response to Overflows: A Mechanism for the Azores Current

Abstract The oceanic response to overflows is explored using a two-layer isopycnal model. Overflows enter the open ocean as dense gravity currents that flow along and down the continental slope. While descending the slope, overflows typically double their volume transport by entraining upper oceanic water. The upper oceanic layer must balance this loss of mass, and the resulting convergent flow produces significant vortex stretching. Overflows thus represent an intense and localized mass and vorticity forcing for the upper ocean. In this study, simulations show that the upper ocean responds to the overflow-induced forcing by establishing topographic β plumes that are aligned more or less along isobaths and that have a transport that is typically a few times larger than that of the overflows. For the topographic β plume driven by the Mediterranean overflow, the occurrence of eddies near Cape St. Vincent, Portugal, allows the topographic β plume to flow across isobaths. The modeled topographic β-plume circu.
Surface water temperature, salinity, and density changes in the northeast Atlantic during the last 45,000 years: Heinrich events, deep water formation, and climatic rebounds

We developed a new method to calculate sea surface salinities (SSS) and densities (SSD) from planktonic foraminiferal δ18O and sea surface temperatures (SST) as determined from planktonic foraminiferal species abundances. SST, SSS, and SSD records were calculated for the last 45,000 years for Biogeochemical Oceanic Flux Study (BOFS) cores 5K and 8K recovered from the northeast Atlantic. The strongest feature is the dramatic drop in all three parameters during the Heinrich “ice-rafting” events. We modelled the possibility of deepwater formation in die northeast Atlantic from the SSD records, by assuming that the surface waters at our sites cooled as they flowed further north. Comparison with modelled North Atlantic deepwater densities indicates that there could have been periods of deepwater formation between 45,000 and 30,000 14C years B.P. (interrupted by iceberg meltwater input of Heinrich event 3 and 4, at 27,000 and 38,000 14C years B.P.) and during the Holocene. No amount of cooling in the northeast Atlantic between 30,000 and 13,000 years could cause deep water to form, because of the low salinities resulting from the high meltwater inputs from icebergs. Our records indicate that after each Heinrich event there were periods of climatic rebound, with milder conditions persisting for up to 2000 years, as indicated by the presence of warmer and more saline water masses. After these warm periods conditions returned to average glacial levels. These short term cold and warm episodes in the northeast Atlantic are superimposed on the general trend towards colder conditions of the Last Glacial Maximum (LGM). Heinrich event 1 appears to be unique as it occurs as insolation rose and was coeval with the initial melting of the Fennoscandian ice sheet. We propose that meltwater input of Heinrich event 1 significantly reduced North Atlantic Deep Water formation, reducing the heat exchange between the low and high latitudes, thus delaying deglaciation by about 1500 radiocarbon years (2000 calendar years).
The Canadian Climate Centre Second-Generation General Circulation Model and Its Equilibrium Climate

Abstract The Canadian Climate Centre second generation general circulation model (GCMII) is described. The description emphasizes aspects in which the new model differs from the 1984 model (GCMI) as described by Boer and collaborators. Important features of the new version include an interactive cloudiness parameterization, improved solar and terrestrial radiative beating calculations, a more sophisticated treatment of land surface processes, and a simple ocean mixed-layer model with a thermodynamic sea ice component. Results from a ten-year climate simulation made with the new model are presented and compared with observed climatology. The comparison is made for the December-February and June-August periods. The model reproduces the observed climatology in a generally successful manner.
Aerosol particles at a high‐altitude site on the Southeast Tibetan Plateau, China: Implications for pollution transport from South Asia

Bulk aerosol samples were collected from 16 July 2008 to 26 July 2009 at Lulang, a high‐altitude (>3300m above sea level) site on the southeast Tibetan Plateau (TP); objectives were to determine chemical characteristics of the aerosol and identify its major sources. We report aerosol (total suspended particulate, TSP) mass levels and the concentrations of selected elements, carbonaceous species, and water‐soluble inorganic ions. Significant buildup of aerosol mass and chemical species (organic carbon, element carbon, nitrate, and sulfate) occurred during the premonsoon, while lower concentrations were observed during the monsoon. Seasonal variations in aerosol and chemical species were driven by precipitation scavenging and atmospheric circulation. Two kinds of high‐aerosol episodes were observed: one was enriched with dust indicators (Fe and Ca2+), and the other was enhanced with organic and elemental carbon (OC and EC), SO42−, NO3−, and Fe. The TSP loadings during the latter were 3 to 6 times those on normal days. The greatest aerosol optical depths (National Centers for Environmental Protection/National Center for Atmospheric Research reanalysis) occurred upwind, in eastern India and Bangladesh, and trajectory analysis indicates that air pollutants were transported from the southwest. Northwesterly winds brought high levels of natural emissions (Fe, Ca2+) and low levels of pollutants (SO42−, NO3−, K+, and EC); this was consistent with high aerosol optical depths over the western deserts and Gobi. Our work provides evidence that both geological and pollution aerosols from surrounding regions impact the aerosol population of the TP.
Retinoic acid orchestrates fibroblast growth factor signalling to drive embryonic stem cell differentiation

Embryonic stem (ES) cells fluctuate between self-renewal and the threshold of differentiation. Signalling via the fibroblast growth factor (Fgf)/Erk pathway is required to progress from this dynamic state and promote mouse ES cell differentiation. Retinoic acid also induces differentiation in many cellular contexts, but its mechanism of action in relation to Fgf/Erk signalling in ES cells is poorly understood. Here, we show for the first time that endogenous retinoid signalling is required for the timely acquisition of somatic cell fate in mouse ES cells and that exposure to retinoic acid advances differentiation by a dual mechanism: first increasing, but in the long-term decreasing, Fgf signalling. Rapid retinoid induction of Fgf8 and downstream Erk activity on day 1 in differentiation conditions may serve to ensure loss of self-renewal. However, more gradual repression of Fgf4 by retinoic acid is accompanied by an overall reduction in Erk activity on day 2, and the acquisition of neural and non-neural fates is now advanced by inhibition of Fgf signalling. So, although blocking Fgf/Erk activity is known to promote ES cell self-renewal, once cells have experienced a period of such signals, subsequent inhibition of Fgf signalling has the opposite effect and drives differentiation. We further show in the embryo that retinoid repression of Fgf signalling promotes neural differentiation onset in an analogous step in the extending embryonic body axis and so identify attenuation of Fgf signalling by retinoic acid as a conserved fundamental mechanism driving differentiation towards somatic cell fates.
Efficacy of Low Interatrial Septum and Right Atrial Appendage Pacing for Prevention of Permanent Atrial Fibrillation in Patients With Sinus Node Disease: Results From the Electrophysiology-Guided Pacing Site Selection (EPASS) Study

Patients with sinus node dysfunction may develop atrial fibrillation (AF). This study shows that pacing the interatrial septum can play a role in the prevention of permanent/persistent AF in patients with intra-atrial conduction delay to the posterior triangle of Koch. These patients can be identified by a quick electrophysiological study during the implanting procedure, as described in the report. The lead technology to permanently pace specific atrial sites is available, and the algorithms for continuous atrial pacing are also available. Finally, the pacemakers automatically store data about AF burden, simplifying the assessment of the development/progression of the disease.
Modality-Invariant Image Classification Based on Modality Uniqueness and Dictionary Learning.

We present a unified framework for image classification of image sets taken under varying modality conditions. Our method is motivated by a key observation that the image feature distribution is simultaneously influenced by the semantic-class and the modality category label, which limits the performance of conventional methods for that task. With this insight, we introduce modality uniqueness as a discriminative weight that divides each modality cluster from all other clusters. By leveraging the modality uniqueness, our framework is formulated as unsupervised modality clustering and classifier learning based on modality-invariant similarity kernel. Specifically, in the assignment step, each training image is first assigned to the most similar cluster according to its modality. In the update step, based on the current cluster hypothesis, the modality uniqueness and the sparse dictionary are updated. These two steps are formulated in an iterative manner. Based on the final clusters, a modalityinvariant marginalized kernel is then computed, where the similarities between the reconstructed features of each modality are aggregated across all clusters. Our framework enables the reliable inference of semantic-class category for an image, even across large photometric variations. Experimental results show that our method outperforms conventional methods on various benchmarks, such as landmark identification under severely varying weather conditions, domain-adapting image classification, and RGB and near-infrared (NIR) image classification.