A statistical downscaling method (SDSM) was evaluated by simultaneously downscaling air temperature, evaporation, and precipitation in Haihe River basin, China. The data used for evaluation were large-scale atmospheric data encompassing daily NCEP/NCAR reanalysis data and the daily mean climate model results for scenarios A2 and B2 of the HadCM3 model. Selected as climate variables for downscaling were measured daily mean air temperature, pan evaporation, and precipitation data from 11 weather stations in the Haihe River basin. The results obtained from SDSM showed that: (1) the pattern of change in and numerical values of the climate variables can be reasonably simulated, with the coefficients of determination between observed and downscaled mean temperature, pan evaporation, and precipitation being 99%, 93%, and 73%, respectively; (2) systematic errors existed in simulating extreme events, but the results were acceptable for practical applications; and (3) the mean air temperature would increase by about 0.7°C during 2011~2040; the total annual precipitation would decrease by about 7% in A2 scenario but increase by about 4% in B2 scenario; and there were no apparent changes in pan evaporation. It was concluded that in the next 30 years, climate would be warmer and drier, extreme events could be more intense, and autumn might be the most distinct season among all the changes.

Nanowire-based plasmonic metamaterials exhibit many intriguing properties related to the hyperbolic dispersion, negative refraction, epsilon-near-zero behavior, strong Purcell effect, and nonlinearities. We have experimentally and numerically studied the electromagnetic modes of individual nanowires (meta-atoms) forming the metamaterial. High-resolution, scattering-type near-field optical microscopy has been used to visualize the intensity and phase of the modes. Numerical and analytical modeling of the mode structure is in agreement with the experimental observations and indicates the presence of the nonlocal response associated with cylindrical surface plasmons of nanowires.

Near-field scanning optical microscopy (NSOM) enables observation of light-matter interaction with a spatial resolution far below the diffraction limit without the need for a vacuum environment. However, modern NSOM techniques remain subject to a few fundamental restrictions. For example, concerning the aperture tip (a-tip), the throughput is extremely low, and the lateral resolution is poor; both are limited by the aperture size. Meanwhile, with regard to the scattering tip (s-tip), the signal-to-noise ratio (SNR) appears to be almost zero; consequently, one cannot directly use the measured data. In this work, we present a plasmonic tip (p-tip) developed by tailoring subwavelength annuli so as to couple internal radial illumination to surface plasmon polaritons (SPPs), resulting in an ultrastrong, superfocused spot. Our p-tip supports both a radial symmetric SPP excitation and a Fabry-Pérot resonance, and experimental results indicate an optical resolution of 10 nm, a topographic resolution of 10 nm, a throughput of 3.28%, and an outstanding SNR of up to 18.2 (nearly free of background). The demonstrated p-tip outperforms state-of-the-art NSOM tips and can be readily employed in near-field optics, nanolithography, tip-enhanced Raman spectroscopy, and other applications.

The effect of chemical stresses on diffusion has been investigated. A thin plate of isotropic material with boundary conditions of constant surface chemical potential and constant surface stresses is considered. If there is no rotation in the isotropic solid, the effective diffusivity arising from the chemical stresses is proportional to the concentration. The chemical stresses enhance the mass transfer because of increasing diffusivity. The initial surface concentration may differ from the final surface concentration for the constant surface chemical potential.

The authors report the investigation of surface plasmon waves (SPW) generated by single nanohole and nanohole arrays. Scattering-type scanning near-field microscopy is used to directly observe near-field distribution. The images after Fourier transformation display characteristic patterns that match with the derived analytic formula. The correspondence helps to identify the role of the scanning tip in generating SPW, making possible of the removal of this tip-induced effect. This study provides a means to perform in-depth investigation on surface plasmon polaritons.

The active phase of the East Asian summer monsoon (EASM) in Taiwan during May and June, known as Meiyu, produces substantial precipitation for water uses in all sectors of society. Following a companion study that analysed the historical increase in the Meiyu precipitation, the present study conducted model evaluation and diagnosis based on the EASM lifecycle over Taiwan. Higher and lower skill groups were identified from 17 Couple Model Intercomparison Project Phase 5 (CMIP5) models, with five models in each group. Despite the difference in model performance, both groups projected a substantial increase in the Meiyu precipitation over Taiwan. In the higher skill group, weak circulation changes and reduced low‐level convergence point to a synoptically unfavourable condition for precipitation. In the lower skill group, intensified low‐level southwesterly winds associated with a deepened upper level trough enhance moisture pooling. Thus, the projected increase in Meiyu precipitation will likely occur through the combined effects of (1) the extension of a strengthened North Pacific anticyclone enhancing southwesterlies; and (2) more systematically, the Clausius–Clapeyron relationship that increases precipitation intensity in a warmer climate. The overall increase in the Meiyu precipitation projected by climate models of variable performance supports the observed tendency toward more intense rainfall in Taiwan and puts its early June 2017 extreme precipitation events into perspective.

The anti-reflection properties of the inverted pyramidal structures with the tips for crystalline silicon solar cells are studied numerically and experimentally, and the comparisons with inverted pyramidal structures without the tips are given. Because the light has more multiple reflection between different surfaces of the inverted pyramidal structures with the tips and more light energies are trapped and absorbed by the solar cell materials, the structures with the tips can have smaller reflection. This study can be useful for the designs of textured structures for the solar cells or other anti-reflection applications.

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