Is Glacier Wastage Accelerating in Northwestern North America?

北美西北部的几乎所有冰川都在失去质量，而且在过去十年左右的时间里，与之前几十年的速度相比，冰川的速度加快了近两倍。显而易见的问题是，这种加速是否还在继续。为了解决这一问题，需要为一项为期三年的计划提供资金，该计划将在2007年至2009年期间使用小型飞机激光高度计系统对北美西北部的冰川进行海拔廓线测量。还将有第四个年头进行分析。结果将使我们比目前拥有更好的区域覆盖范围，并使我们能够更准确和更新地估计该来源区域对平均海平面上升的贡献。在所有年份，都将有一项解释性计划，重点是冰川消融对海平面的影响，并特别关注趋势，以及冰川和气候之间的联系。其目标是：1)在国际极地年期间继续冰川概况和分析计划；2)对该项目和我们的相关(以及更早的)NASA项目中的冰川概况数据进行完整的缩减、分析和存档；3)开发一种高效和准确的方法，从测量到的冰川到北美西北部的所有冰川地区外推我们的航线海拔变化和体积变化估计，以便可以在适当的时间间隔更新对这些冰川对海平面上升的区域贡献的估计；以及4)从冰川在气候系统中的作用来解释我们的结果。更广泛的影响：在气候变化的这一时期，对北美西北部冰川消融的测量引起了公众的兴趣，并得到了媒体的大量报道。公众认为，冰川消融是一种令人印象深刻的晴雨表和例证，是持续气候变化的结果，最实际的后果是冰川消融对全球平均海平面上升的贡献。因此，冰川消融是否继续加速的问题引起了人们的极大兴趣。海平面上升对世界沿海人口的影响是巨大的，包括直接洪灾和相关现象，如冰川后隆起、海岸侵蚀加剧和风暴潮风险。

ABSTRACTLingleOPP-0612Almost all the glaciers of northwestern North America are losing mass, and at a rate that has accelerated by a factor of almost two during the past decade or so compared with the rate over several previous decades. The obvious question is whether this acceleration is continuing. To address this question, funds are requested for a three-year program to continue elevation profiling of the glaciers of northwestern North America, which will be carried out with a small-aircraft laser altimeter system from 2007 through 2009. There will be a fourth year for analysis. The results will give us better regional coverage than we have at present, and permit more accurate and updated estimations of the contribution to rising mean sea level from this source region. In all years, there will be an interpretative program that will focus on the effect of glacier wasting on sea level with special attention to trends, and on the connections between glaciers and climate. The objectives are to: 1) continue the glacier profiling and analysis program through the International Polar Year; 2) complete reduction, analysis and archiving of glacier profiling data from this and our related (and earlier) NASA projects; 3) develop an efficient and accurate method for extrapolating our flight-line elevation changes and volume change estimates from measured glaciers to all of the glacierized areas of northwestern North America, so estimates of the regional contribution from these glaciers to rising sea level can be updated at suitable intervals; and 4) interpret our results in terms of the role of glaciers in the climate system. Broader impacts: The measurement of glacier wastage in northwestern North America is of interest to the public during this time of climate change and has received much press coverage. The public sees the wastage of glaciers as an impressive kind of barometer and illustration and a consequence of continuing climate change, the most practical consequence being the contribution of glacier wastage, globally to rising mean sea level. Thus, the question of whether glacier wastage is continuing to accelerate is of considerable interest. The effects of rising sea level on the coastal populations of the world are enormous and include direct flooding and related phenomena such as post-glacial uplift, increasing coastal erosion, and risk from storm surges.