Recent Trends in Melting Conditions on the Antarctic Peninsula and Their Implications for Ice-sheet Mass Balance and Sea Level
Recent Trends in Melting Conditions on the Antarctic Peninsula and Their Implications for Ice-sheet Mass Balance and Sea Level
复制标题
南极半岛融化状况的最新趋势及其对冰盖质量平衡和海平面的影响
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
D. Vaughan
中科院分区：
文献类型：
--
作者：
D. Vaughan
摘要南极半岛气象站的长期记录表明，融化条件的年持续时间呈强烈的上升趋势。在每种情况下，趋势都具有统计学意义，并代表着融化潜力的大幅增加;例如，1950年至2000年期间，法拉第/Vernadsky站的记录显示，正度日数（PDD）增加了74%。一个简单的参数化的可能影响变暖的积雪融化速度表明，整个南极半岛冰盖的增加从28 ± 12 Gt a−1在1950年，到2000年的54 ± 26 Gt a−1。如果在未来50年内以类似的变暖速度，这一数值可能达到100 ± 46 Gt a−1。大部分增加的融水并没有流入海洋，而是在冰盖中重新冻结，很难预测消融的一部分将成为径流;然而，根据已建立的径流标准进行的计算表明，南极半岛的贡献，作为对气候变暖的直接和立即反应，是显著的，相当于全球海平面上升（0.008-0.055）mm a−1。考虑到未来的变暖，这一数字在未来50年内很容易增加两倍。由于径流量增加而产生的这种贡献，可能会因冰川排出冰盖的任何动态不平衡而增加。这一发现似乎与之前评估的结论相矛盾，包括政府间气候变化专门委员会，该委员会认为南极洲径流对海平面上升的贡献微不足道。
Abstract Long-term records from meteorological stations on the Antarctic Peninsula show strong rising trends in the annual duration of melting conditions. In each case, the trend is statistically significant and represents a major increase in the potential for melting; for example, between 1950 and 2000 the record from Faraday/Vernadsky Station showed a 74% increase in the number of positive degree-days (PDDs). A simple parameterization of the likely effects of the warming on the rate of snow melt suggests an increase across the Antarctic Peninsula ice sheet from 28 ± 12 Gt a−1 in 1950, to 54 ± 26 Gt a−1 by 2000. Given a similar rate of warming over the next 50 years this may reach 100 ± 46 Gt a−1. The majority of this increased meltwater does not drain into the sea but is refrozen in the ice sheet, and it is difficult to predict the fraction of ablation that will become runoff; however, a calculation based on an established criterion for runoff indicates that the contribution from the Antarctic Peninsula, as a direct and immediate response to climate warming is significant, equivalent to (0.008–0.055) mm a−1 of global sea level rise. Given future warming this could easily treble in the coming 50 years. This contribution due to increased runoff could be augmented by any dynamic imbalance in the glaciers draining the ice sheet. This finding appears to contradict the conclusions of previous assessments, including the Intergovernmental Panel on Climate Change, which considered the contribution of runoff from Antarctica to sea level rise would be insignificant.