Glacial Lakes in Peru: Evolution, Hazards and impacts of climate change.

由于气候变化，秘鲁的冰川正在迅速消退，这导致了许多大型冰川湖的形成，其中许多冰川湖由冰碛石筑成，如果冰碛石筑坝失败或被淹没，可能会发生灾难性的排水。湖泊排水的一个主要触发因素是最近暴露的山谷壁和不稳定的冰碛导致的岩石滑坡和碎屑流入湖泊。来自这些湖泊的冰湖溃决洪水（GLOFs）对社区和基础设施造成了重大危害，也影响了该地区的供水。在秘鲁，冰川湖泊爆发的洪水在20世纪造成约3.2万人死亡，并摧毁了重要的经济基础设施、定居点和宝贵的可耕地。尽管这些湖泊很重要，但关于它们未来的行为和全球臭氧层变化的未来风险，仍有许多悬而未决的问题。例如，我们不知道秘鲁有多少个冰川湖，也不知道这些冰川湖的规模是否在扩大，也不知道它们是否越来越容易受到由岩石滑坡和泥石流引起的快速排水的影响。因此，我们不知道哪些湖泊可能引起全球暖化，也不知道全球暖化的风险是在增加还是在减少。因此，该项目将回答有关秘鲁山区冰川湖泊和冰川危害的过去、现在和未来发展的问题。我们将编制秘鲁所有冰川山区冰川湖泊的第一个完整清单，评估它们在过去和未来冰川衰退的影响下随时间的大小变化，并评估它们对突然排水的脆弱性变化。我们将研究当前和未来全球气候变化下全球气候变化的幅度、频率和分布；编制秘鲁历史GLOFs的首份完整清单，并确定未来有可能形成冰川危害的地点。我们将首次评估现在和未来冰川湖发生山体滑坡的风险。我们将使用基于物理的数值模型在被确定为具有高危险性的地点模拟GLOFs，并利用这些模拟进行灾害和洪水风险预测，从而为秘鲁的决策者提供信息。为此，我们将重点关注五个主要问题：1。利用文献资料、遥感和实地调查，我们将编制一份秘鲁冰川地区所有冰川湖泊和过去GLOF遗址的清单。使用最新一代的气候模型来评估秘鲁山区未来变暖和降水变化的最大风险。这将使我们能够确定未来湖泊排水风险的地区，我们将为未来湖泊排水风险制定山区排名。湖泊脆弱性评估我们将识别当前和可能的未来冰川危害，重点关注随着冰川消退而发展的滑坡和泥石流风险；3 .确定未来可能易受影响的湖泊和潜在的GLOF地点。GLOFs模型。我们将(a)建立控制GLOF行为的物理过程；(b)分析选定的前全球风洞的洪水曲线，以确定对下游的影响。5. 评估秘鲁全球森林灾害的社会经济影响和全球森林灾害预测：我们将(a)确定秘鲁各地潜在的全球森林灾害地点，并评估潜在的社会经济脆弱性；(b)重建以前的全球GLOFs及其影响；(c)对潜在的旱涝灾害地点的下游影响进行数值模拟。这一建议符合官方发展援助的要求，因为它将通过提供改进的降低风险方法来促进秘鲁的经济发展，这些方法可通过有关政府机构应用于水电项目和高海拔矿山以及当地社区。本项目制定的GLOF风险协议可应用于其他存在GLOF风险的dac上市国家（如阿根廷）。

Glaciers in Peru are undergoing rapid recession in response to climate change and this has helped produce numerous large glacial lakes, many of which are dammed by moraines and are likely to drain catastrophically if the moraine dams fail or are overtopped. A major trigger of lake drainage is rock slides and debris flows into lakes from recently-exposed valley walls and unstable moraines. Glacial Lake Outburst Floods (GLOFs) from these lakes pose a significant hazard to communities and infrastructure and also impact water supplies in the region. In Peru, outburst floods from glacial lakes have caused ~ 32,000 deaths in the 20th century, as well as destroying vital economic infrastructure, settlements and valuable arable land. Despite the importance of these lakes, there are many unanswered questions concerning their future behaviour and the future risk of GLOFs. For instance, we do not know how many glacial lakes there are in Peru, nor whether these are growing in size, nor whether they are becoming more or less vulnerable to rapid drainage caused by rock slides and debris flows. We therefore do not know which lakes might cause GLOFs, nor whether the risk of GLOFs is increasing or decreasing. As a result, this project will answer questions concerning the past, present and future development of glacial lakes and glacier hazards in Peruvian mountains. We will produce the first complete inventory of glacial lakes in all the glaciated mountain regions of Peru, assess their changes in size over time in response to past and future glacier recession and assess changes in their vulnerability to sudden drainage. We will investigate the changing magnitude, frequency, and distribution of GLOFs under current and future global climate change; produce the first complete inventory of historical GLOFs in Peru and identify sites that have the potential to develop glacial hazards in the future. We will, for the first time, assess the risk of landslides into glacial lakes now and into the future. We will use physically-based numerical models to simulate GLOFs at sites identified as posing a high hazard and use these simulations to make hazard and flood risk predictions that can inform decision-makers in Peru. To do this we will focus on five main issues:1. Glacial lake development and GLOF inventories in the past and presentUsing literature, remote-sensing and fieldwork, we will compile an inventory of all glacial lakes and past GLOF sites in the glaciated regions of Peru. 2. Climate modellingUse the latest generation of climate models to assess mountain areas of Peru at most risk of future warming and precipitation change. This will enable us to identify areas of future lake drainage risk and we will develop a ranking of mountain areas for future risk of lake drainage.3. Assessment of lake vulnerabilityWe will identify current and likely future glacier hazards focusing on the developing landslide and debris flow risk as glaciers recede; establish the locations of potential future vulnerable lakes and potential GLOF sites.4. Model GLOFs.We will (a) establish the physical processes that govern GLOF behaviour; (b) analyse flood hydrographs of selected former GLOFs to establish downstream impacts. 5. Assess the socio-economic effects of GLOFs in Peru and GLOF prediction: We will (a) identify potential GLOF sites across Peru and assess potential socio-economic vulnerability; (b) reconstruct former GLOFs and their impacts; (c) conduct numerical simulations of downstream impacts for potential GLOF sites.This proposal is ODA compliant as it will promote the economic development of Peru by providing improved risk reduction methods that can be applied to hydropower projects and high-altitude mines as well as to local communities through relevant government agencies. The GLOF risk protocols developed in this project can be applied to other DAC-listed countries where GLOF hazards exist (e.g. Argentina)