Understanding and Constraining Future Arctic Climate Change

uclaffunds用于理解和约束当前一代气候模式中重要的北极海冰反照率反馈（SIAF）。为了减少模型中反馈模拟之间的传播，有必要确定可用于评估反馈真实性的观测约束。这里的主要困难是，反馈是未来气候的各个方面，不能直接观察到。为了避免这种情况，首席研究员（PI）的策略是量化模拟的SIAF强度，因为它影响了温带地区外部强迫气候变率的最可观测和最突出的例子——当前气候的季节周期。如果当前季节周期模拟的SIAF强度能够很好地预测气候变化背景下的反馈强度，那么当前季节周期中对反馈的观测约束将直接导致未来气候预测中反馈强度模式间传播的减少。这似乎是PI之前关于雪反照率反馈的工作的情况，并且已经概述了考虑到反馈特性的SIAF产生类似结果的策略。与此工作相对应的一项重要工作将是确定当前气候模拟的哪些方面对SIAF强度及其模式间传播影响最大。PI已经开发了一个数学框架，以便从模型输出中进行诊断。预计这项工作将集中在海冰反照率的参数化上，但也将研究北极云在调制SIAF中的作用，以及海洋-海冰相互作用的作用。

Hall 0714083UCLAFunds are provided to understand and constrain the important arctic sea-ice-albedo feedback (SIAF) in the current generation of climate models. To reduce the spread between simulations of feedbacks in models, it is necessary to identify observational constraints that can be used to evaluate the feedback's realism. The central difficulty here is that the feedbacks are aspects of future climate, and cannot be observed directly. To circumvent this, the strategy of the principal investigator (PI) is to quantify simulated SIAF strength as it impacts the most observable and prominent example of externally-forced climate variability in the extratropics - the current climate's seasonal cycle. If simulated SIAF strength in the current seasonal cycle is an excellent predictor of feedback strength in the climate change context, then observational constraints on the feedback in the current seasonal cycle should lead directly to reductions in the intermodel spread of feedback strength in the future climate predictions. This appears to have been the case with the PI's previous work on snow albedo feedback, and a strategy for producing similar results for SIAF that takes into account the feedback's peculiarities has been outlined. An essential counterpart to this effort will be determining which aspects of current climate simulations influence SIAF strength and its intermodel spread the most. The PI has developed a mathematical framework to facilitate these diagnoses from model output. It is anticipated that the work will focus on sea ice albedo parameterizations, but will also examine the role of arctic clouds in modulating SIAF, as well as the role of ocean-sea-ice interaction.