Helical rolls are known to play a significant role in modulating both the mean and turbulence structure of the atmospheric boundary layer in tropical cyclones. However, in-situ measurements of these rolls have been limited due to safety restrictions. This study presents analyses of data collected by an aircraft operated by the Hong Kong Observatory in Typhoon Kalmaegi (1415) and Typhoon Nida (1604). Examination of the flight-level data at ~ 600 m altitude confirmed the existence of sub-kilometer-scale rolls. These rolls were mostly observed in the outer-core region. Turbulent momentum fluxes were computed using the eddy correlation method. The averaged momentum flux of flight legs with rolls was found to be ~ 2.5 times that of legs without rolls at a similar wind speed range. This result suggests that rolls could significantly modulate turbulent transfer in the tropical cyclone boundary layer. This roll effect on turbulent fluxes should be considered in the planetary boundary layer parameterization schemes of numerical models simulating and forecasting tropical cyclones.
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http://dx.doi.org/10.1038/s41598-021-97766-7 | DOI Listing |
Ann N Y Acad Sci
January 2025
Institute for Earth System Science and Remote Sensing, Leipzig University, Leipzig, Germany.
Vegetation is often viewed as a consequence of long-term climate conditions. However, vegetation itself plays a fundamental role in shaping Earth's climate by regulating the energy, water, and biogeochemical cycles across terrestrial landscapes. It exerts influence by consuming water resources through transpiration and interception, lowering atmospheric CO concentration, altering surface roughness, and controlling net radiation and its partitioning into sensible and latent heat fluxes.
View Article and Find Full Text PDFEntropy (Basel)
December 2024
Department of Structure of Matter, Thermal Physics and Electronics, Faculty of Physics, Complutense University of Madrid, 28040 Madrid, Spain.
The entropy production in the polarization phenomena occurring in the underlimiting regime, when an electric current circulates through a single cation-exchange membrane system, has been investigated in the 3-40 °C temperature range. From the analysis of the current-voltage curves and considering the electro-membrane system as a unidimensional heterogeneous system, the total entropy generation in the system has been estimated from the contribution of each part of the system. Classical polarization theory and the irreversible thermodynamics approach have been used to determine the total electric potential drop and the entropy generation, respectively, associated with the different transport mechanisms in each part of the system.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Solid State Physics and Nonlinear Physics, Faculty of Physics and Technology, AL-Farabi Kazakh National University Almaty 050040 Kazakhstan.
In this paper, Gd-doped ZrO gate dielectric films and metal-oxide-semiconductor (MOS) capacitors structured as Al/ZrGdO /Si were prepared using an ultraviolet ozone (UVO)-assisted sol-gel method. The effects of heat treatment temperature on the microstructure, chemical bonding state, optical properties, surface morphology and electrical characteristics of the ZrGdO composite films and MOS capacitors were systematically investigated. The crystalline phase of the ZrGdO films appeared only at 600 °C, indicating that Gd doping effectively inhibits the crystallization of ZrO films.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China.
Nitryl chloride (ClNO) is a key precursor of chlorine radicals, influencing atmospheric oxidation and secondary pollutants formation. Few studies have examined the ClNO chemistry from the perspective of the planetary boundary layer. Here, we conducted a vertically resolved investigation of ClNO at six heights (ranging from 5 to 335 m) on a 356 m tower in the Pearl River Delta, China, during winter 2021.
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
January 2025
A*STAR Skin Research Labs (A*SRL), Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, #07-01, Nanos, Singapore, 138669, Republic of Singapore.
Purpose: Basal Cell Carcinoma (BCC), the most common subtype of non-melanoma skin cancers (NMSC), is prevalent worldwide and poses significant challenges due to their increasing incidence and complex treatment considerations. Existing clinical approaches, such as Mohs micrographic surgery, are time-consuming and labour-intensive, requiring meticulous layer-by-layer excision and examination, which can significantly extend the duration of the procedure. Current optical imaging solutions also lack the necessary spatial resolution, penetration depth, and contrast for effective clinical use.
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