论文摘要
身处深海盆地之上的西南极洲冰原历来被认为处于不稳定状况中。我们利用数值模型调查了斯韦茨冰川对海洋融化的敏感性,不管其不稳定的撤退是否已开始。我们的模型再现了相较于估计状况而观测到的因海洋融化而强制受到的损失。我们对21世纪所模拟的的损失较温和(<每年0.25毫米海平面)但至此之后逐渐增加。除了最低熔融的情况,模拟表明早期阶段的崩溃已经开始。不太确定的是时间尺度,即200至900年之间范围内不同模拟快速崩溃的起始(海平面上升>每年1毫米)。
Abstract
Resting atop a deep marine basin, the West Antarctic Ice Sheet has long been considered prone to instability. Using a numerical model, we investigated the sensitivity of Thwaites Glacier to ocean melt and whether its unstable retreat is already under way. Our model reproduces observed losses when forced with ocean melt comparable to estimates. Simulated losses are moderate (<0.25 mm per year at sea level) over the 21st century but generally increase thereafter. Except possibly for the lowest-melt scenario, the simulations indicate that early-stage collapse has begun. Less certain is the time scale, with the onset of rapid (>1 mm per year of sea-level rise) collapse in the different simulations within the range of 200 to 900 years.