At a time when nobody has yet landed on the Antarctic continent (1879), this presentation and accompanying paper predicts the morphology, dynamics and thermal regime of the Antarctic ice sheet. Mathematical modelling of the ice sheet is based on the assumptions that the thickness of tabular icebergs reflects the average thickness of the ice at the margin and that the surface gradients are comparable to those of reconstructed former ice sheets in the Northern Hemisphere. The modelling shows that (a) ice is thickest near the centre at the South Pole and thins towards the margin; (b) the thickness at the pole is independent of the amount of snowfall at that place; and (c) the mean velocity at the margin, assuming a mean annual snowfall of two inches per year, is 400–500 feet per year. The thermal regime of the ice sheet is influenced by three heat sources – namely, the bed, the internal friction of ice flow and the atmosphere. The latter is the most significant and, since ice has a downwards as well as horizontal motion, this carries cold ice down into the ice sheet. Since the temperature at which ice melts is lowered by pressure at a rate of 0.0137 °F for every atmosphere of pressure (something known since 1784), much of the ice sheet and its base must be below the freezing point. Estimates of the thickness of ice at the centre depend closely on the surface gradients assumed and range between 3 and 24 miles. Such uncertainty is of concern since both the volume and gravitational attraction of the ice mass have an effect on global sea level. In order to improve our estimate of the volume of ice, we will have to wait 76 years for John Glen to develop a realistic flow law for ice.

中文翻译：

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南极冰的厚度及其与冰期的关系

在没有人登陆南极大陆的时候（1879 年），这份报告和随附的论文预测了南极冰盖的形态、动力学和热状况。冰盖的数学建模基于以下假设：板状冰山的厚度反映了边缘冰的平均厚度，并且表面梯度与北半球重建的前冰盖的表面梯度相当。模型显示（a）冰在南极中心附近最厚，向边缘变薄；(b) 极地的厚度与该地的降雪量无关；(c) 边缘的平均速度，假设年平均降雪量为每年 2 英寸，则为每年 400-500 英尺。冰盖的热状态受三个热源的影响——即床、冰流的内摩擦和大气。后者是最重要的，因为冰有向下和水平运动，这会将冷冰带入冰盖。由于每个大气压下冰融化的温度都会以 0.0137°F 的速度降低（自 1784 年以来就已知），因此大部分冰盖及其底部必须低于冰点。对中心冰层厚度的估计密切依赖于假设的表面梯度，范围在 3 到 24 英里之间。这种不确定性令人担忧，因为冰块的体积和引力都会对全球海平面产生影响。为了改进我们对冰体积的估计，