School of Civil Engineering and the Environment and the Tyndall Centre for Climate Change Research, University of Southampton, Southampton SO17 1BJ, UK.
Philos Trans A Math Phys Eng Sci. 2011 Jan 13;369(1934):161-81. doi: 10.1098/rsta.2010.0291.
The range of future climate-induced sea-level rise remains highly uncertain with continued concern that large increases in the twenty-first century cannot be ruled out. The biggest source of uncertainty is the response of the large ice sheets of Greenland and west Antarctica. Based on our analysis, a pragmatic estimate of sea-level rise by 2100, for a temperature rise of 4°C or more over the same time frame, is between 0.5 m and 2 m--the probability of rises at the high end is judged to be very low, but of unquantifiable probability. However, if realized, an indicative analysis shows that the impact potential is severe, with the real risk of the forced displacement of up to 187 million people over the century (up to 2.4% of global population). This is potentially avoidable by widespread upgrade of protection, albeit rather costly with up to 0.02 per cent of global domestic product needed, and much higher in certain nations. The likelihood of protection being successfully implemented varies between regions, and is lowest in small islands, Africa and parts of Asia, and hence these regions are the most likely to see coastal abandonment. To respond to these challenges, a multi-track approach is required, which would also be appropriate if a temperature rise of less than 4°C was expected. Firstly, we should monitor sea level to detect any significant accelerations in the rate of rise in a timely manner. Secondly, we need to improve our understanding of the climate-induced processes that could contribute to rapid sea-level rise, especially the role of the two major ice sheets, to produce better models that quantify the likely future rise more precisely. Finally, responses need to be carefully considered via a combination of climate mitigation to reduce the rise and adaptation for the residual rise in sea level. In particular, long-term strategic adaptation plans for the full range of possible sea-level rise (and other change) need to be widely developed.
未来气候引起的海平面上升范围仍高度不确定，人们持续担忧，在 21 世纪海平面大幅上升的情况无法排除。不确定性的最大来源是格陵兰和西南极洲的大型冰盖对气候变化的响应。基于我们的分析，如果在同一时期温度上升 4°C 或以上，到 2100 年海平面上升的务实估计值将在 0.5 米至 2 米之间——海平面上升到较高端的概率被判断为非常低，但概率无法量化。然而，如果这种情况成为现实，一个指示性分析表明，其潜在影响是严重的，在本世纪内，有多达 1.87 亿人（占全球人口的 2.4%）可能被迫迁移。通过广泛升级保护措施，这是可以避免的，尽管这需要高达全球国内生产总值的 0.02%，在某些国家则更高。在不同地区，保护措施成功实施的可能性不同，在小岛屿、非洲和亚洲部分地区，这种可能性最低，因此这些地区最有可能出现沿海地区被放弃的情况。为了应对这些挑战，需要采取多轨道方法，如果预计气温上升低于 4°C，这种方法也是合适的。首先，我们应该监测海平面，及时发现海平面上升速度的任何显著加速。其次，我们需要提高对可能导致海平面快速上升的气候诱发过程的理解，特别是两大冰盖的作用，以更好地制作模型，更准确地量化未来可能的海平面上升。最后，需要通过气候缓解来减少上升，以及适应海平面上升的剩余部分，来仔细考虑应对措施。特别是，需要广泛制定涵盖各种可能海平面上升（和其他变化）的长期战略适应计划。
