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11.
This article presents a personal perspective on an academic and research vocation spanning a period of over 45 years. It starts with my early involvement in geography and climatology and terminates with my recent experience in a large interdisciplinary research venture. The presentation highlights, with specific examples, the importance of mentors. Also emphasized is the indispensable input of colleagues and graduate students to successful research endeavours. Most of my career has been centred on McMaster University, and I naturally draw on my experiences there. There have been great changes in the research world over the past few decades. Although the number of faculty and graduate students at McMaster remained relatively constant, the research output per person more than doubled. This is attributed in large part to the accelerating technological advancements in our ability to measure and our ability to process and manipulate data. In the environmental sciences, this has revolutionized the spatial and temporal scope of the scientific questions that can be addressed. Such major changes have stimulated a marked trend towards interdisciplinary research that has evolved from mainly wishful talking to active pursuit in a search to understand complex environmental interactions. Important among these is gaining insights into the processes and feedbacks driving climate change, whether natural or anthropologically induced. Equally important is gaining an understanding of the potential impacts resulting from climate change. My perception of my successes, failures and near misses divides chronologically into three periods that cover research in the early years, research in the central subarctic and research in the Mackenzie River Basin.  相似文献   
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Since 1955 the NSW Department of Water Resources has undertaken extensive river training works on many NSW streams. In the Hunter Valley alone over $23 million have been spent and more than 850 km of channel have been treated Published work suggests that river training works are usually undertaken in response to a pre-existing problem of river instability but can also induce adverse hydrogeomorphic effects. One of the treated streams, the Allyn River, had been supposedly degraded by the constructed works. It was alleged that vegetation clearing, channel excavations, alignment straightening and bank protection works had decreased roughness thus increasing velocity and flood frequency. As a result, what were thought to be relatively moderate floods were eroding the banks and destroying the floodplain. A critical evaluation of the available hydraulic, hydrologic and geomorphic data revealed that the river training works were a response to, rather than a cause of river instability.  相似文献   
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The proposed grand Canal project calls for the damming of James Bay and the diversion of its water southward. This first part of a two-part study models some potential impacts on the climate, water balance, and growth patterns in the James Bay coastal zone. Use is made of a linear relationship of Bowen ratio and temperature, developed from studies of coastal wetlands in southern and northwestern James Bay and central Hudson Bay. It is hypothesized that changing James Bay into a fresh-water lake and disrupting its coastal currents would result in a delayed Bay ice melt of unknown length in the spring. Allowing a delay to vary between 0 and 30 days results in the prediction of lesser evaporation and greater water surplus. These differences in magnitude increase with the length of delayed melt, but in all cases are most strongly evident during the peak of the growing season. Colder and wetter conditions would have a strong ecological impact on all coastal areas of western and southern James Bay. In the northwest this could change the species composition of coastal flora, cause forests to retreat from the coast, and result in the growth of permafrost there.  相似文献   
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Since 1946, there has been a significant increase in annual rainfall in the Hunter Valley, especially for stations in the western sector. Contemporaneous increases in rainfall intensities of frequent storms and flood peaks have also been recorded. From analyses of the data, together with a review of recent environmental changes in the Hunter Valley, it is concluded that human disturbance of the catchment has played no significant part in the increase in flood magnitude. Instead, the change in floods may be completely attributed to the variation in rainfall regime. The altered hydrologic regime combined with a decrease in sediment yield from extra-channel sources appears to be the primary cause of recent river channel changes.  相似文献   
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