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The equatorial Pacific Walker Circulation (EPWC), characterized by ascending motion (lower sea‐level pressure [SLP]) over Indonesia and descending motion (higher SLP) over the Eastern Pacific, has been widely recognized. Yet, little is known about a zonal circulation over the North Pacific (hereafter referred to as NPZC) with ascent over the west coast of Canada and descent over the east coast of Russia, which plays an important role in maintaining Northern Hemisphere mid‐latitude climate. Here we provide evidence for the existence of the NPZC by comparing the eastern and western North Pacific around 50°N with the western and eastern equatorial Pacific, respectively. We find that the EPWC and NPZC bear strong similarity in many essential aspects, such as the zonal gradients of temperature and SLP, precipitation records and prevailing winds, and so on, thus, suggesting a NPZC. The existence of a NPZC is also strongly supported by observations in situ using radiosonde balloon soundings as well as numerical simulations. [ABSTRACT FROM AUTHOR]

When a ship is moored by a single anchor at the anchorage, its combined motions (i.e. yaw, sway, surge, etc.) are usually induced by external forces. Previous studies have gained some insights into the forces on anchor chains, but the motions for Capesize vessels still need to be further investigated. The length of anchor chain required for safe anchoring also needs to be carefully calculated rather than determined solely by the experience and judgement of Captains. The relationship between the length of chain and water depth, wind force, current velocity and the trim (draught difference forward/aft) requires further study. Our new methods consider all necessary factors which may exert significant influence on ships, including not only the water depth at the anchoring location but also the particulars of the ships, its equipment and the environmental conditions. Here, a numerical simulation model to describe the behaviour of an anchored Capesize ship is presented, with the comparison of results between simulations and real time model tests carried out. A discussion highlights the important features of the methods which provide mariners with theoretical solutions. [ABSTRACT FROM AUTHOR]