Linear response functions to project contributions to future sea level
Linear response functions to project contributions to future sea level
复制标题
预测对未来海平面贡献的线性响应函数
DOI：
10.1007/s00382-012-1471-4
复制
发表时间：
2013
期刊：
影响因子：
4.6
通讯作者：
A. Levermann
中科院分区：
文献类型：
--
作者：
R. Winkelmann;A. Levermann
我们提出了线性响应函数来分别估计格陵兰和南极洲的热膨胀和固体冰排放对海平面的贡献。响应函数形式引入了时间依赖性，允许未来海平面上升速度受到过去气候变化的影响。我们发现，对于这里所考虑的三个子系统中的每一个，这种依赖于时间的函数类型R(T)∼tα是相同的。通过将通过响应函数获得的海平面估计与综合模型的预测进行比较来评估该方法的有效性。一维的纯垂直扩散情况，对应于α=−0.5，对于所有典型的浓缩路径来说，是直到21世纪中叶海洋内热膨胀的有效近似。α=−=0.7时的近似值得到了显著改进。对于格陵兰岛的固体冰流量，我们找到了一个最佳值α=−0.7。与以前的研究不同，我们得出的结论是，由于动态变薄，格陵兰的固体冰排放量在0.42m海平面当量范围内。由南极洲表面变暖引起的冰排放最好用正值α=100.1来捕捉，这反映了这样一个事实，即在我们的模型中，冰损失随着可用于软化冰的累积热量而增加。
We propose linear response functions to separately estimate the sea-level contributions of thermal expansion and solid ice discharge from Greenland and Antarctica. The response function formalism introduces a time-dependence which allows for future rates of sea-level rise to be influenced by past climate variations. We find that this time-dependence is of the same functional type, R(t) ∼ tα, for each of the three subsystems considered here. The validity of the approach is assessed by comparing the sea-level estimates obtained via the response functions to projections from comprehensive models. The pure vertical diffusion case in one dimension, corresponding to α = −0.5, is a valid approximation for thermal expansion within the ocean up to the middle of the twenty first century for all Representative Concentration Pathways. The approximation is significantly improved for α = − 0.7. For the solid ice discharge from Greenland we find an optimal value of α = −0.7. Different from earlier studies we conclude that solid ice discharge from Greenland due to dynamic thinning is bounded by 0.42 m sea-level equivalent. Ice discharge induced by surface warming on Antarctica is best captured by a positive value of α = 0.1 which reflects the fact that ice loss increases with the cumulative amount of heat available for softening the ice in our model.
影响因子：
14.6
作者：
Martijn Gough
通讯作者：
Martijn Gough