This study quantifies the impact of atmospheric rivers (ARs) on rainfall in New Zealand. Using an automated AR detection algorithm, daily rainfall records from 654 rain gauges, and various atmospheric reanalysis datasets, we investigate the climatology of ARs, the characteristics of landfalling ARs, the contribution of ARs to annual and seasonal rainfall totals, and extreme rainfall events between 1979 and 2018 across the country. Results indicate that these filamentary synoptic features play an essential role in regional water resources and are responsible for many extreme rainfall events on the western side of mountainous areas and northern New Zealand. In these regions, depending on the season, 40–86% of the rainfall totals and 50–98% of extreme rainfall events are shown to be associated with ARs, with the largest contributions predominantly occurring during the austral summer. Furthermore, the median daily rainfall associated with ARs is 2–3 times than that associated with other storms. The results of this study extend the knowledge on the critical roles of ARs on hydrology and highlight the need for further investigation on the landfalling AR physical processes in relation to global circulation features and AR sources, and hydrological hazards caused by ARs in New Zealand.

Water transparency is commonly used to indicate the combined effect of hydrodynamics and the aquatic environment on water quality throughout a river network. However, how water transparency responds to these indicators still needs to be explored, especially their complicated nonlinear relationship; thus, this study represents an analysis of the Suzhou civil river network. Using an artificial neural network (ANN) hydrological model and a multiple linear model (MLR) with in-situ data between 2013–2019, we investigated the Suzhou River’s sensitivity to the six factors and water transparency, which including flow velocity and data from five categories of water-quality monitoring data: total suspended matter (TSS), water temperature (TE), dissolved oxygen (DO), chlorophyll (Chl) and chemical oxygen demand (COD). The results suggest that the ANN model can achieve better performance than the MLR model. Furthermore, results also show a well-established correlation between enhanced hydrodynamics and improved water transparency when the flow velocity ranged from 0.22 to 0.45 m/s. Overall, COD is a vital factor for the SD prediction because including the COD can see a notable improvement in the ANN model (with a correlation coefficient of 0.918). This study demonstrates that the ANN model with hydrodynamic and water quality parameters can achieve a better prediction of water transparency than other discussed models for a coastal plain urban river network.

The high-precision sound velocimeter is the standard of other sound velocimeters. It needs to have a reliable mechanical structure. The structural stability is the core part of this machine, and only tiny deform can be permitted in its working condition with the specified temperature in sea water. To ensure its high-precision in its working and changing environment condition, author need to calculate its deformation by transient thermal-structural interaction analysis. Using interaction between thermal and structural by finite software ANSYS Workbench this paper finished the numerical calculation of its working in designed condition. The analysis result show that: The maximum displacement appears in the forked places of the sample's structural stability which equipped with transducers, and the maximum stress appears in the same place by the surrounded sea water in the specified. The deforms and stress fit the design requirement, provide the basis for the design.

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Atmospheric Rivers (ARs) are filamentary channels of strong poleward water vapour transport in the midlatitudes. Recent studies have demonstrated the significant role of ARs in New Zealand's water resources and extreme precipitation events.Motivated by a recently proposed AR-impact ranking scale in the USA to enhance the communication between scientific communities and water sectors, here the characteristics of AR events with peak daily rainfall greater than 100 mm over 5 divided sectors are further investigated, and the AR-impact ranking scale is evaluated for the applicability for such events in New Zealand. Previous studies have found that the windward side along coastlines favours locally high rainfall. As such, we show that the strength and duration of those AR events also vary with event direction, and NW-AR events are normally stronger and longer than those of other directions throughout the country. However, over the eastern areas, most of those events are easterly directed and produce anomalously high rainfall, despite being ranked as "Weak AR" events based on the current AR-impact ranking scale. It is found that easterly directed ARs originating from the west make landfall along the eastern coastline from the ocean (i.e., from the east) or simply the onshore flow. Therefore, our results suggest that localised ranking scale or considering more parameters, such as AR over-land direction, might help improve the AR-impact ranking scale applicability over eastern regions in New Zealand.