Improving glacier melt modelling through ground-based profiling of atmospheric boundary layer

我们需要一个测量冰川表面温度和风速垂直剖面的传感器。这些测量对于开发更好的冰川对水流和海平面上升的贡献模型是非常必要的。全球山地冰川的退缩是现代气候变化的一个关键指标，冰川的质量损失导致海平面上升和季节性河流。在加拿大西部，冰川径流维持夏季水流对水力发电、农业灌溉和供水至关重要。未来几十年，全世界的冰川将发生迅速而前所未有的变化。然而，目前用于区域和全球尺度应用的冰川模式依赖于校准，并且由于校准数据的稀疏性，其模拟中的不确定性范围为50 - 50%。迫切需要缩小不确定性，我们的目标是通过开发适用于区域和全球尺度的基于物理的冰川融化模型来满足这一需求。这些模式与定标无关，普遍适用，但需要输入气候数据（例如入射太阳和长波辐射、近地表温度和风速），这些数据通常是从模拟气候场获得的，这些模拟气候场的分辨率过于粗糙，无法充分代表驱动冰川融化的局地尺度过程。这种方法的关键挑战是成功地“缩小”风和温度场的规模，并充分模拟湍流热通量，这是熔化的重要因素。为了应对这些挑战，我们将开发一个风和温度降尺度的变表模型，并改进目前评估湍流热通量的方法。但是，为了取得成功，我们迫切需要风速、温度和湍流特征的垂直剖面测量，以便开发和验证这些新模型/方法。这些测量是我们现有的加拿大西部冰川近地表测量和遥感观测监测网络中必不可少的缺失部分。这项建议要求一种成本效益高的传感器，这种传感器尚未在山地冰川上使用，用于在加拿大西部冰川上进行垂直剖面测量。所要求的传感器将推进几个正在进行的研究项目，涉及至少三所大学的现有和未来的HQP。通过推进冰川融化的建模，我们最终将在必要的细节水平上提供冰川对海平面上升和河流流量的贡献的更可信的预测，以告知当地政策制定者和用户社区。使用该设备的资助人员将为气候变化下淡水资源风险评估的前沿研究做出贡献，并将接受地球科学、计算和数据分析方面的高水平培训，为他们在学术界、政府或私营企业的广泛机会做好准备。

We request a sensor for measuring vertical profile of temperature and wind speed above glacier surfaces. The measurements are critically needed for development of better models of glacier contribution to streamflow and sea level rise. The retreat of mountain glaciers worldwide is a key indicator of modern climate change, with mass loss from glaciers contributing to sea level rise and to seasonal streamflow. Across Western Canada, maintenance of summer streamflow by glacier runoff is essential for hydro-power generation, agricultural irrigation and water supply. The coming decades will see rapid and unprecedented changes to glaciers worldwide. However, current glacier models for regional and global scale application are calibration-dependent and, due to sparsity of data for calibration, suffer from >50% uncertainty range in their simulations. There is an urgent need to narrow the uncertainty, and our goal is to address this need by developing physics-based models for glacier melt applicable for regional and global scales. These models are calibration independent and universally applicable, but require input climate data (e.g. incoming solar and longwave radiation, near-surface temperature and wind speed), commonly obtained from modelled climate fields that are too coarsely resolved to adequately represent local-scale processes driving glacier melt. The key challenges in this approach, are to successfully `downscale' the wind and temperature fields, and to adequately simulate turbulent heat fluxes, which are important contributors to melt. We will tackle these challenge by developing a katabatic model for downscaling of wind and temperature, and by improving current methods for assessing turbulent heat fluxes. But, in order to succeed, we critically need vertical profile measurements of wind speed, temperature and turbulent characteristics so that these new models/methods can be developed and validated. These measurements are essential missing component in our existing monitoring network of near-surface measurements and remote-sensing observations of glaciers in Western Canada. This proposal requests a cost-effective sensor, which has not yet been used at mountain glaciers, for vertical profile measurements at glaciers across Western Canada. The requested sensor will advance several ongoing research projects involving existing and future HQP across at least three universities. By advancing the modelling of glacier melt, we will ultimately provide more credible projections of glacier contribution to sea-level rise and streamflow at the level of detail necessary to inform local policy makers and user communities. Funded personnel working with this equipment will contribute to the cutting-edge research on risk assessment of freshwater resources under climate change, and will receive high-level training in geosciences, computing and data analysis, preparing them for a broad range of opportunities in academia, government or private industry.