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Storm surge is one of the most devastating marine disasters in China, leading to tremendous economic damage and a large number of casualties. Combined storm surge hazard assessment and zonation is an important method for coastal disaster risk reduction and mitigation management. Based on observational data from tide-gauge and hydrological stations in coastal areas, we analyzed storm surge hazard intensity and generated a storm surge hazard map at the county level using the expected values of storm surge and over-warning water levels. The results show that 87, 67, 62, and 40 counties along the coast of China are exposed to the first (highest), second (higher), third (medium), and fourth (low) degree of hazard level, respectively. The areas with the highest risk of storm surge are the coasts of Bohai Bay, Laizhou Bay, and the Yangtze Delta, the coast from the north of Fuzhou to the south of Zhejiang, and the coastal area of Huizhou, Pearl River, and Yangjiang in Guangdong Province. This assessment, which is based on a national storm surge hazards map, can provide decision-making support for the government’s urban planning of coastal cities and site selection in large national projects.

Giant magnetoimpedance (GMI) and the GMI effect of a Co-based fiber beam were investigated in the frequency range of 0.1–10 MHz, and the influence of distance between adjacent fibers on the distribution of the surface circumferential magnetic field and GMI effect was analyzed. Compared with a single fiber, the distribution of the surface magnetic field of paralleled fibers is non-uniform, induced by magnetic interaction between metal fibers. The originally uniformly distributed circumferential magnetic field changes into two obvious coexisting parts: one stronger and one weaker. The results prove that the strengthened circumferential magnetic field determines the GMI effect and sensitivity. It is found that the maximum surface of the circumferential magnetic field is reinforced by 88% when the four fibers are as closely parallel as possible; the GMI effect is greatest under higher field sensitivity. At 5 MHz, the sensitivity of the four-fiber beam reaches 3090 V/T, an increase of 277% compared with a single fiber. However, the magnetic interaction fades with the increase in distance between fibers and as the distribution of the surface magnetic field becomes even. The maximum magnetic field also becomes gradually equal to the level of a single fiber. When the distance is 1 mm, the maximum surface magnetic field is increased by 3.2%, and the improvement in the GMI effect is correspondingly slight. Therefore, a strong magnetic interaction among fibers can improve the intensity of the surface circumferential magnetic field and give rise to a fine GMI effect and high field sensitivity in Co-based metal fibers.