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At least 1,423 records · Page 79
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Process for the Recovery of Actinide and Lanthanide Oxides via Thermal Decomposition and Calcination of Loaded Diglycolamide Resin

Diglycolamide (DGA) resin, a product produced by Eichrom Technologies, Inc. employs TODGA (N,N,N',N'-tetraoctyldiglycolamide) as the active extractant, which will be used by Savannah River National Laboratory to extract trivalent actinides and lanthanides from dissolved irradiated Mark-18A targets. The final form of the extracted material will be an oxide suitable for shipment. A two-step process was developed and validated for the direct recovery of actinides and lanthanides loaded on I-grade DGA resin as nitrates by thermally drying and decomposing resin loaded with Nd(III), a surrogate for trivalent actinides and lanthanides, under inert conditions followed by calcining the resultant residue in air to provide an oxide product. Further, a stepwise heating profile up to 385°C under argon gas flow resulted in 85% to 89% mass loss during the resin drying and decomposition step, and calcination of the resultant Nd-loaded resin residue provided an overall material mass loss of ≥ 98%. Recoveries from resin saturated with Nd(III) from 7 M and 0.35 M nitric acid subjected to this process were 30.7 mg and 27.6 mg Nd/g dry resin, respectively, representing an average of 96.1% of Nd retained in the resin bed.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2020

Ring patterns generated by an expanding colloidal meniscus

The drop-and-dry is a common technique allowing for creation of periodic nanoparticle (NP) structures for sensing, photonics, catalysis, etc. However, the reproducibility and scalability of this approach for fabrication of NP-based structures faces serious challenges due to the complexity of the simple, at first glance, evaporation process. In this work we study the effect of the spatial confinement on the NP self-assembly under slow solvent evaporation, when the air-liquid-substrate contact line (CL) expands from the center towards the walls of a cylindrical cell, forming a toroid. Using in situ video monitoring of the stick-slip CL motion, we find regular hydrodynamic perturbations in the meniscus, and reveal fine details of the formation of quasiperiodic rings of close packed NP layers. We report that drying of the toroidal NP droplet has a number of important differences from drying of the classical hemispherical colloidal drops. In toroidal drops we observe linear-in-time average meniscus motion, in contrast to the hemispherical drops where the meniscus moves as a square root of time. While both droplet geometries produce NP ring patterns, the ring width for the toroidal drop decreases with increasing ring radius, while it decreases with decreasing the radius of the hemispherical drop. We suggest that free ligands are the main cause of the Marangoni instabilities driving the periodic vorticity in the meniscus. Finally, we show that the usually ignored contact line tension may yield a considerable contribution to the CL pinning causing the CL slip-stick motion and the ring formation.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Impact of temperature and concentration on flow behaviour of reconstituted lactose and protein–rich dairy powders

To help with designing the drying process, this study investigated the flow behaviour of lactose and protein-rich reconstituted dairy powders at 25°C and 50°C. Lactose-rich samples, 50% dried whey (DW) and 60% whey protein concentrate (WPC35) did not follow the Herschel–Bulkley model because of presence of lactose crystals. Reconstituted 50% skim milk powder (SMP) and protein-rich dairy powders exhibited shear-thinning behaviour (n < 0.3). With increasing concentration, whey protein concentrate/isolate (WPC80/WPI) and micellar casein concentrate high-solid dispersions exhibited more shear-thinning behaviour (n < 0.4). Furthermore, understanding shear-thinning behaviour of lactose-rich and protein-rich reconstituted dairy powders will provide basis for optimising drying parameters.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Overcoming environmental constraints to high-yielding eastern cottonwood productivity in the southeastern United States

The global demand for biomass is rising, and Populus species are among the most productive temperate woody plants. This 6-year study, conducted in Sumter County, South Carolina, USA evaluated the effects of supplemental irrigation and fertilization on crown and leaf traits, dry weight productivity, and clonal variation in Populus deltoides. Eight commercially available clones (‘ST148’, ‘S2C20’, ‘3167’, ‘ST72’, ‘20WV’, ‘S7C1’, ‘ST70’, and ‘S7C15’) were assessed. Drip irrigation was applied to maintain soil tension at either 33 kPa (15% volumetric soil moisture) or 1500 kPa (10%). Nutrient treatments via weekly fertigation applications consisted of two levels: a high annual rate (initially 85 kg elemental nitrogen ha−1 year−1, increasing to 182 kg ha−1 year−1 at Year 3, then reduced to 135 kg ha−1 year−1 thereafter) and a low rate at 50% of the high treatment. Dry weight yields were estimated using standing tree measurements. Results revealed significant clonal differences in leaf area index (LAI) that peaked in Year 3, with the fastest-growing clones exhibiting lower LAI values. At Ages 2 and 3, these clones also showed higher concentrations of K, Ca, B, Cu, and Mn in leaves, along with lower Mg and Zn concentrations. Both annual height and diameter growth varied significantly by treatment and clone, with the largest height increases observed in the low fertilizer treatments from Year 3 onward. Biomass production in all irrigated plots exceeded that of non-irrigated plots across all biomass components at Ages 4, 5, and 6. Furthermore, stem-to-root dry weight ratios increased more rapidly in the best-performing treatment–clone combinations compared to non-irrigated plots. Notably, P. deltoides plots receiving fertilizer had higher soil carbon concentrations (i.e., percent C) compared to adjacent sweetgum, sycamore, and agricultural plots. These findings highlight the potential of targeted irrigation strategies to enhance biomass productivity in P. deltoides plantations.

Tuskan, Gerald [ORNL] (ORCID:0000000301061289)↗
DOE OSTI2020

Cut–and–chip harvester material capacity and fuel performance on commercial-scale willow fields for varying ground and crop conditions

Shrub willow (Salix spp.) is capable of producing commercially attractive amounts of biomass in short rotations, but harvesting costs and logistics remain a concern. There is a particular need for information about harvesting operations on larger, commercial short–rotation woody crop systems. Another recent issue on commercial fields in northern New York is commercial growers conducting harvests during the growing season rather than the recommended dormant season when fields may be too wet to harvest. This study evaluated and modeled the in–field performance of a cut–and–chip harvester for almost 700 wagonloads of chips operating in commercial willow fields in a wider array of crop and field conditions than have been previously reported. Analysis indicated that the time of harvest (leaf–on or leaf–off) and whether site conditions were wet or dry affected the harvester's material capacity. Mean material capacity was greatest for leaf–off, dry conditions (71.8 Mg/hr) and lowest for leaf–on harvests, which were similar for wet (30.4 Mg/hr) and dry conditions (29.7 Mg/hr). Mean crop specific fuel consumption ranged between 1.3 and 3.3 L/Mg, but can get considerably higher for standing biomasses below 40 Mg/ha. Wet ground conditions and leaf–on harvests tend to decrease material capacity and increase fuel consumption as the harvester has to divert power to forward movement and material processing. Relationships for material capacity and fuel consumption based on standing biomass, time of harvest and ground conditions will be essential for evaluating and modeling the economic and environmental impacts of commercial–scale willow operations.

09 BIOMASS FUELS↗
DOE OSTI2024

Altering plant carbon allocation to stems has distinct effects on rhizosphere soil microbiome assembly, interactions, and potential functions in sorghum

Abstract Altering plant carbon allocation from leaves to stems is key to improve biomass for forage, fuel, and renewable chemicals. The sorghum dry stalk ( D ) locus controls a quantitative trait for sugar accumulation, with enhanced carbon allocation in the stems of juicy green ( dd ) sorghum but reduced carbon allocation in that of dry white ( DD ) sorghum. However, it remains unclear whether altering sorghum sugar accumulation in stem affects below‐ground microbiome. Here we investigated sorghum rhizosphere soil microbiome in near isogenic lines with different magnitude of carbon allocations and accumulation in the stems. Results showed that enhanced carbon accumulation in stems of juicy green sorghum results in stronger selection in rhizosphere microbiome assembly. The rhizosphere soil microbial communities selected in juicy green sorghum tended to be fast‐growing microbial taxa which possessed potential functions that would promote higher potential capacity to use chemically labile carbon sources and potentially result in higher potential decomposition rates. We found the rhizosphere microbes selected by juicy green sorghum form weaker interactions than dry white sorghum. This is the first comprehensive study revealing how the different magnitude of carbon allocations to stems regulates microbial community assembly, microbial interaction, and microbial functions. This study indicates that future plant modification for bioenergy crops should also consider the impacts on belowground microbial community without compromising the sustainability.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Water and vapor transport in algal‐fungal lichen: Modeling constrained by laboratory experiments, an application for Flavoparmelia caperata

ABSTRACT Algal‐fungal symbionts share water, nutrients, and gases via an architecture unique to lichens. Because lichen activity is controlled by moisture dynamics, understanding water transport is prerequisite to understand their fundamental biology. We propose a model of water distributions within foliose lichens governed by laws of fluid motion. Our model differentiates between water stored in symbionts, on extracellular surfaces, and in distinct morphological layers. We parameterize our model with hydraulic properties inverted from laboratory measurements of Flavoparmelia caperata and validate for wetting and drying. We ask: (1) Where is the bottleneck to water transport? (2) How do hydration and dehydration dynamics differ? and (3) What causes these differences? Resistance to vapor flow is concentrated at thallus surfaces and acts as the bottleneck for equilibrium, while internal resistances are small. The model captures hysteresis in hydration and desiccation, which are shown to be controlled by nonlinearities in hydraulic capacitance. Muting existing nonlinearities slowed drying and accelerated wetting, while exaggerating nonlinearities accelerated drying and slowed wetting. The hydraulic nonlinearity of F. caperata is considerable, which may reflect its preference for humid and stable environments. The model establishes the physical foundation for future investigations of transport of water, gas, and sugar between symbionts.

Potkay, Aaron↗
DOE OSTI2024

Pretest Modeling A Spent Nuclear Fuel Seismic Shake Test

The U.S. Department of Energy Spent Fuel and Waste Science and Technology (SFWST) program is planning to conduct a series of full-scale shake table tests to simulate hypothetical earthquake conditions and record the response of surrogate spent nuclear fuel (SNF) assemblies in a dry canister storage system mockup. The shake table motions will represent a range of hypothetical earthquake conditions at hypothetical locations in the continental U.S. to generally define the range of mechanical loads that SNF can be expected to experience during extended dry storage periods. This paper describes the pretest predictions made with LS-DYNA models of the mockup storage systems. The test will use two dry storage system configurations, a mockup vertical concrete cask (VCC) and a mockup horizontal storage module (HSM). The test will use a production-quality canister and basket. Within the canister will be four instrumented fuel assemblies with fuel rods containing surrogate mass and 28 instrumented dummy assemblies that are intended to match the mass and outer dimension of a fuel assembly. The finite element models include models of the VCC and HSM on the shake table to calculate the system level dynamic responses and separate single fuel assembly models to calculate stress and strain in fuel assembly components. Both types of models include nonlinear behavior like rod-to-rod contact and the ability for VCC’s to rock and slide. This paper presents the expected response of the VCC, HSM, and fuel assemblies to the shake table testing that is planned to start in April of 2024. The earthquake conditions represent seismic hazards in the 2,000-to-20,000-year return period range. The test data is expected to confirm the expectation that fuel rod cladding will remain intact, fuel assembly structural components like guide tubes will remain intact, and no significant VCC sliding or tipping will occur in the range of conditions to be tested with the shake table.

Klymyshyn, Nicholas A.↗
DOE OSTI2024

THERMAL MODELING OF HANFORD CESIUM AND STRONTIUM CANISTERS DURING SIMULATED LOADING

A computational fluid dynamics (CFD) model was built to simulate planned testing of heater assemblies within a canister and overpack for the Hanford Lead Canister (HLC) project. The HLC is a canister storage system that will contain heaters to simulate the decay heat of nuclear material and provide the canister storage system with environmental conditions equivalent to the operating conditions on a dry storage pad. The HLC will be equipped with long-term data collection and monitoring systems to provide an early warning of corrosion, pitting, cracking, or other signs of canister degradation that might threaten the integrity of the containment boundary over the potentially long term of dry storage. An important part of the HLC development is to make pretest numerical predictions for the behavior of the heated canister during the simulated radiolytic decay heat testing, which simulates the dry storage system during loading operations. The simulated radiolytic decay heat test is planned for mid-2024 in a configuration that includes the heater assembly, overpack, and canister, but with the lids removed to allow loading cesium and strontium capsules into the canister. One of the goals of the test is to evaluate the thermal behavior of the canister and overpack assembly in the ambient air of the test facility, which will provide data critical to validating the thermal models and understanding how the HLC will perform as a system once deployed. To best approximate real-world conditions, the CFD model includes the full air volume of the mock-up truck bay the heated canister test will be performed in, enabling detailed investigation of how the heated canister affects airflow around it. Rigorous pre-deployment testing of the complete HLC cask and canister system is intended to be completed before the HLC is deployed in the 2028 timeframe. This study presents the pre-test temperature predictions of the simulated radiolytic decay heat test. A description of the heater assembly, canister, and overpack system is presented. The model was developed with the commercial CFD software STAR-CCM+. An uncertainty analysis was run with the CFD model to determine the uncertainty in the temperature predictions and provide a range over which the predicted temperatures are expected to vary. The uncertainty analysis was preformed by coupling STAR-CCM+ with the software Dakota, which provides advanced parametric analyses, including quantification of margins and uncertainty with computational models. This work is expected to provide insight into SNF canister behavior.

Carpenter-Graffy, Dina E.↗
DOE OSTI2020

The lightness of water vapor helps to stabilize tropical climate

Moist air is lighter than dry air at the same temperature, pressure, and volume because the molecular weight of water is less than that of dry air. We call this the vapor buoyancy effect. Although this effect is well documented, its impact on Earth’s climate has been overlooked. Here, we show that the lightness of water vapor helps to stabilize tropical climate by increasing the outgoing longwave radiation (OLR). In the tropical atmosphere, buoyancy is horizontally uniform. Then, the vapor buoyancy in the moist regions must be balanced by warmer temperatures in the dry regions of the tropical atmosphere. These higher temperatures increase tropical OLR. This radiative effect increases with warming, leading to a negative climate feedback. At a near present-day surface temperature, vapor buoyancy is responsible for a radiative effect of 1 W/m 2 and a negative climate feedback of about 0.15 W/m 2 per kelvin.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

SolVap_StarTer (Solvent Evaporation Graphical User Interface) [SWR-26-029]

SolVap_StarTer is an open-source solvent evaporation GUI. The software combines previously published (peer-reviewed scientific journals) evaporation and crystallization physics into an easy-to-use graphical interface. The software will allow the user to specify a coating composition and drying environment, and then predict the evolution of the film as it dries. Potential applications include tracking the change in multi-solvent composition and solute concentration in solution-processed perovskites films, predicting the point of crystallization, and calculating equivalent processing parameters for transferring a process between different coating and drying methods. Github repo: https://github.com/NatLabRockies/SolVap Streamlit app: https://solvap.streamlit.app/

Starger, Jesse [National Laboratory of the Rockies↗
DOE OSTI2020

Analytical Investigation of the Role of Lateral Mixing in the Evolution of Nonprecipitating Cumulus. Part II: Dissolving Stage

A minimalistic analytical model allowing analysis of the dissolving stage of nonprecipitating convective clouds is proposed. The model takes into account two mechanisms: turbulent mixing with a dry environment and cloud volume settling. The temporal changes in the spatial structure of a cloud and in its immediate environment in the course of cloud dissolving are analyzed. The comparison of the effects of a temperature increase in the course of cloud descent and mixing with dry surrounding air shows that the descent is a dominating factor determining a decrease in the liquid water content (LWC), while mixing has a stronger effect on the cloud shape. Narrowing/broadening of clouds due to lateral mixing with dry air during cloud dissolving is determined by the potential evaporation parameter proportional to the ratio of the saturation deficit in the cloud environment to LWC. An equation for cloud dissolving time is obtained. After a cloud totally dissolves, it leaves behind an area with humidity exceeding that of the environment. The main parameter determining the dissolving time is the downdraft velocity. It should exceed 50 cm s -1 in order to provide reasonable dissolving time. The turbulent intensity, LWC, and humidity of the environment air also have an impact on dissolving time: the lower the LWC and the humidity of environment air, the faster cloud dissolving is. The simple solution presented in this paper can be useful for evaluation of cloud characteristics at the dissolving stage and can be included in procedures of parameterization of cloud cover formed by nonprecipitating or slightly precipitating cumulus clouds (Cu). Values of the environment humidity and temperature, LWC at cloud top, cloud width, vertical velocity of downdraft, and the turbulent coefficient should be parameters of this parameterization.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

A Theory for the Response of Tropical Moist Convection to Mechanical Orographic Forcing

Abstract Spatial patterns of tropical rainfall are strongly influenced by mountains. Although theories for precipitation induced by convectively stable upslope ascent exist for the midlatitudes, these do not represent the interaction of moist convection with orographic forcing. Here, we present a theory for convective precipitation produced by the mechanical interaction of a tropical ridge with a basic-state horizontal wind. Deviations from this basic state are represented as the sum of a “dry” perturbation, due to the stationary orographic gravity wave, and a “moist” perturbation that carries the convective response. The moist component dynamics are subject to the weak temperature gradient approximation; they are forced by the dry mode’s influence on lower-tropospheric moisture and temperature. Analytical solutions provide estimates of the precipitation distribution, including peak precipitation, upstream extent, and rain shadow extent. The theory can be used with several degrees of complexity depending on the technique used to compute the dry mode, which can be drawn from linear mountain wave theory or full numerical simulations. To evaluate the theory, we use a set of convection-permitting simulations with a flow-perpendicular ridge in a long channel. The theory makes a good prediction for the cross-slope precipitation profile, indicating that the organization of convective rain by orography can be quantitatively understood by considering the effect of stationary orographic gravity waves on a lower-tropospheric convective quasi-equilibrium state.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Diabatic Eddy Forcing Increases Persistence and Opposes Propagation of the Southern Annular Mode in MERRA-2

Abstract As a dominant mode of jet variability on subseasonal time scales, the Southern Annular Mode (SAM) provides a window into how the atmosphere can produce internal oscillations on longer-than-synoptic time scales. While SAM’s existence can be explained by dry, purely barotropic theories, the time scale for its persistence and propagation is set by a lagged interaction between barotropic and baroclinic mechanisms, making the exact physical mechanisms challenging to identify and to simulate, even in latest generation models. By partitioning the eddy momentum flux convergence in MERRA-2 using an eddy–mean flow interaction framework, we demonstrate that diabatic processes (condensation and radiative heating) are the main contributors to SAM’s persistence in its stationary regime, as well as the key for preventing propagation in this regime. In SAM’s propagating regime, baroclinic and diabatic feedbacks also dominate the eddy–jet feedback. However, propagation is initiated by barotropic shifts in upper-level wave breaking and then sustained by a baroclinic response, leading to a roughly 60-day oscillation period. This barotropic propagation mechanism has been identified in dry, idealized models, but here we show evidence of this mechanism for the first time in reanalysis. The diabatic feedbacks on SAM are consistent with modulation of the storm-track latitude by SAM, altering the emission temperature and cloud cover over individual waves. Therefore, future attempts to improve the SAM time scale in models should focus on the storm-track location, as well as the roles of the cloud and moisture parameterizations. Significance Statement As they circumnavigate the planet, the tropospheric jet streams slowly drift north and south over about 30 days, longer than the normal limit of weather prediction. Understanding the source of this “memory” could improve our knowledge of how the atmosphere organizes itself and our ability to make long-term forecasts. Current theories have identified several possible internal atmospheric interactions responsible for this memory. Yet most of the theories for understanding the jets’ behavior assume that this behavior is only weakly influenced by atmospheric water vapor. We show that this assumption is not enough to understand jet persistence. Instead, clouds and precipitation are more important contributors in reanalysis data than internal “dry” mechanisms to this memory of the Southern Hemisphere jet.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Contributions to the Surface Downwelling Longwave Irradiance during Arctic Winter at Utqiaġvik (Barrow), Alaska

Intrusions of warm, moist air into the Arctic during winter have emerged as important contributors to Arctic surface warming. Previous studies indicate that temperature, moisture, and hydrometeor enhancements during intrusions all make contributions to surface warming via emission of radiation down to the surface. Here, datasets from instrumentation at the Atmospheric Radiation Measurement User Facility in Utqiaġvik (formerly Barrow) for the six months from November through April for the six winter seasons of 2013/14–2018/19 were used to quantify the atmospheric state. These datasets subsequently served as inputs to compute surface downwelling longwave irradiances via radiative transfer computations at 1-min intervals with different combinations of constituents over the six winter seasons. The computed six winter average irradiance with all constituents included was 205.0 W m −2 , close to the average measured irradiance of 206.7 W m −2 , a difference of −0.8%. During this period, water vapor was the most important contributor to the irradiance. The computed average irradiance with dry gas was 71.9 W m −2 . Separately adding water vapor, liquid, or ice to the dry atmosphere led to average increases of 2.4, 1.8, and 1.6 times the dry atmosphere irradiance, respectively. During the analysis period, 15 episodes of warm, moist air intrusions were identified. During the intrusions, individual contributions from elevated temperature, water vapor, liquid water, and ice water were found to be comparable to each other. These findings indicate that all properties of the atmospheric state must be known in order to quantify the radiation coming down to the Arctic surface during winter.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Tracking moisture sources of precipitation over Central Asia: A study based on the water-source-tagging method

Central Asia is a semi-arid to arid region that is sensitive to hydrological changes. We use the Community Atmosphere Model version 5 (CAM5), equipped with a water tagging capability, to investigate the major moisture sources for climatological precipitation and its long-term trends over Central Asia. Europe, the north Atlantic and local evaporation, which explain 33.2±1.5%, 23.0±2.5% and 19.4±2.2% of the precipitation, respectively, are identified as the most dominant moisture sources for northern Central Asia (NCA). For precipitation over southern Central Asia (SCA), Europe, the north Atlantic and local evaporation contributes 25.4±2.7%, 18.0±1.7% and 14.7±1.9%, respectively. In addition, the contributions of South Asia (8.6±1.7%) and Indian Ocean (9.5±2.0%) are also substantial for SCA. Modulated by the seasonal meridional shift of subtropical westerly jet, moisture originating from low- and mid-latitude is important in winter, spring and autumn, while northern Europe contributes more in summer. We also explain the observed drying trends over southeastern Central Asia in spring and over NCA in summer during 1956-2005. The drying trend over the southeastern Central Asia in spring is mainly due to the decrease of local evaporation and weakened moisture fluxes from the Arabian Peninsula and Arabian Sea associated with the warming Western Pacific. The drying trend over NCA in summer can be attributed to the decrease of local evaporation and reduced moisture from northern Europe due to the southward shift of the subtropical westerly jet.

Jiang, Jie↗
DOE OSTI2020

Potential Impacts of Assimilating All-sky Satellite Infrared Radiances on Convection-Permitting Analysis and Prediction of Tropical Convection

Geostationary infrared satellite observations are spatially dense [< 1/(20 km)2] and temporally frequent (< 1/hour). These suggest the possibility of using these observations to constrain sub-synoptic features over data sparse regions, such as tropical oceans. In this study, the potential impacts of assimilating water vapor channel brightness temperature (WV-BT) observations from the geostationary Meteorological Satellite 7 (Meteosat-7) on tropical convection analysis and prediction were systematically examined through a series of ensemble data assimilation experiments. WV-BT observations were assimilated hourly into convection-permitting ensembles using Penn State’s ensemble square root filter (EnSRF). Comparisons against independently observed Meteosat-7 window channel brightness temperature (Window-BT) show that the assimilation of WV-BT generally improved the intensities and locations of large-scale cloud patterns at spatial scales larger than 100 km. However, comparisons against independent soundings indicate that the EnSRF analysis produced a much stronger dry bias than the no data assimilation experiment. This strong dry bias is associated with the use of the simulated WV-BT from the prior mean during the EnSRF analysis step. A stochastic variant of the ensemble Kalman filter (NoMeanSF) is proposed. The NoMeanSF algorithm was able to assimilate the WV-BT without causing such a strong dry bias and the quality of the analyses’ horizontal cloud pattern is similar to EnSRF’s analyses. Finally, deterministic forecasts initiated from the NoMeanSF analyses possess better horizontal cloud patterns above 500 km than those of the EnSRF. These results suggest that it might be better to assimilate all-sky WV-BT through the NoMeanSF algorithm than EnSRF algorithm.

Chan, Man-Yau↗