Climate forcing impacts upon uncertainties in boundary conditions of a repository for spent nuclear fuel caused by a re-glaciation of the Canadian shield

在安大略省，整整50%的电力是由核反应堆提供的，这些反应堆提供的电力不伴随温室气体排放。核能发电的一个不幸的副产品是，它导致产生长寿命放射性核素形式的废物，如果这些核素被释放到环境中，可能会对生物圈的所有组成部分造成重大损害。因此，当务之急是以一种使其免受生物圈逃逸影响的方式储存这些废物。放射性废物处理是目前国际上所有依赖核能为其需求的一小部分提供动力的国家正在解决的问题。可供选择的解决方案包括开发一个深层地质储存库(DGR)，该储存库由一个在地球表面下数百米处建造的金库组成，废物被储存在旨在防止泄漏的罐子中。为加拿大开发这样一个储存库必须面对这样一个问题，即这样一个储存库在重新冰川时期可能会有多大的脆弱性。由于整个国家在过去900,000年中经历了大约9次冰川和冰川消融，而且构成废物的许多放射性核素的半衰期可能超过100,000年，如果发生这种重新冰川事件，储存库的脆弱性问题可能会很严重。这项提案的目的是分析与以前对边界条件的分析有关的不确定性，如果发生进一步的这种冰川事件，这种储存库将受到这些边界条件的制约。造成这种不确定性的最重要因素预计将是与气候强迫的性质有关的因素，而气候强迫是造成重新冰川事件的原因，正是在这个问题上，这项提议得到了关注。为此，采用了最近在模拟最后一次冰川事件方面的最新进展，其中相关的地表边界条件完全耦合到现代大气-海洋耦合气候模式，以便评估以前在以前的冰川边界条件分析中用来推断冰层厚度变化的强迫条件的有效性。

In the Province of Ontario fully 50% of electrical power is provided by nuclear reactors which provide power that is free of accompanying greenhouse gas emissions. An unfortunate byproduct of nuclear power generation is that it leads to the production of waste in the form of long lived radio nucleides which, if they were to be released into the environment, could cause substantial harm to all components of the biosphere. It is therefore imperative that this waste be stored in a way that insolates it from biospheric escape. Radioactive waste disposal is a problem that is currently being addressed by all countries internationally which depend upon nuclear energy to power some fraction of their requirements. The solution of choice involves the development of a Deep Geological Repository (DGR) consisting of a vault constructed many hundreds of meters below Earth's surface in which the waste is stored in canisters designed to prevent escape. The development of such a repository for Canada must face the question as to how vulnerable such a repository might be to an episode of re-glaciation. Since the entire country has been glaciated and deglaciated approximately 9 times during the past 900,000 years, and since the half lives of many of the radio-nucleides of which the waste is composed may exceed 100,000 years, the issue of repository vulnerability in the event of such a re-glaciation event is potentially serious. The goal of this proposal is to provide an analysis of the uncertainties associated with previous analyses of the boundary conditions to which such a repository would be subject if a further such episode of glaciation were to occur. The most significant contributor to this uncertainty is expected to be that associated with the nature of the climate forcing that is responsible for the re-glaciation episode and it is upon this issue that this proposal is focused. To this end very recent advances in the modeling of the last such glaciation event are employed in which the associated surface boundary conditions are fully coupled to a modern coupled atmosphere-ocean climate model in order to assess the validity of the forcing conditions previously employed to infer the ice thickness variations in previous glaciation boundary condition analyses.