Brazilian Experimental datasets for MUlti-Scale interactions in the critical zone under Extreme Drought (BEMUSED)

IOF的这一提案题为“巴西极端干旱临界区多尺度相互作用实验数据集”（BEMUSED），是布里斯托大学（UoB）和圣保罗大学（USP）之间的一项合作项目[适用RCUK-FAPESP牵头机构协议]。困惑认识到，对土壤水分在关键区（从植被冠层到维持生命的土壤和地下水的地球外层）中的作用的更全面的看法在南美洲非常重要。土壤湿度是水文循环的一个关键环境变量，它将地表附近大气条件的快速变化与较慢的地下过程联系起来。然而，由于缺乏与所谓的“超分辨率”水文模型直接兼容的土壤水分测量，我们对关键土壤水分控制因素的了解有限。最近，新的宇宙射线传感器（CRS）技术的发展，以前所未有的亚公里尺度监测土壤水分提供了传统的点尺度传感器和大规模卫星遥感产品之间的缺失环节。近年来，全球建立了CRS网络，但尚未用于热带水文研究（例如，南美洲）。此外，目前的地球系统模型对关键水文过程（包括地下-地表相互作用）的描述有限，这给预测和适应战略带来了极大的挑战。这对于预测干旱等极端事件非常重要，特别是在热带地区等数据稀缺地区。巴西东南部最近（2013-2014年）发生的极端干旱事件严重影响了该地区的水资源，包括为圣保罗大都市区900多万人供水的Cantareira水库系统（世界上最大的水库之一）。在连接地下水和地表水动态方面，缺乏准确的土壤水分作用将继续破坏我们的可预测性技能，因此，为南美洲和全球重要经济社会区域的适应战略提供次优信息。这个机会非常及时，因为它将使两个小组能够相互利用我们目前NERC新研究员“A Multi-大规模土壤湿度-蒸散动力学研究”（AMUSED）项目，利用巴西东南部一个实验集水区的当地现有数据，该集水区最近经历了极端干旱事件。这为进一步评估我们目前的模型开发提供了一个独特的机会（即，土壤中的优先水流和地下水动力学）在具有挑战性的热带地区。同样重要的是，BEMUSED将允许UoB参与与CRS使用相关的知识和技能转让，特别是在从未测试过CRS的热带南美洲地区。CRS计划于2018年在实验集水区安装，因此我们建议首次在南美洲热带地区测试我们在AMUSED下开发的CRS部署/校准指南和数据处理方法，并进一步参与AMUSED的原始影响力活动，通过提供关于“在巴西使用宇宙射线传感器测量土壤湿度。最后，将在巴西举办一次讲习班，讨论提高巴西国家大规模水文气象监测和建模能力的战略，以加强对未来水文气候变化和自然灾害的应对。

This IOF proposal, entitled "Brazilian Experimental datasets for MUlti-Scale interactions in the critical zone under Extreme Drought" (BEMUSED), is a partnership between the University of Bristol (UoB) and University of Sao Paulo (USP) [RCUK-FAPESP Lead Agency Agreement is applied]. BEMUSED recognizes that a more scale-integrated view of the role of soil moisture in the critical zone (the earth's outer layer from vegetation canopy to the soil and groundwater that sustains life) is of great importance in South America. Soil moisture is a key environmental variable of the hydrological cycle connecting the rapid changes in atmospheric conditions near the surface with slower subsurface processes. However, our understanding of key soil moisture controlling factors has been limited due to a lack of soil moisture measurements directly compatible to so-called "hyper-resolution" hydrological models. Recently, the development of new Cosmic-Ray Sensors (CRS) technology for monitoring soil moisture at unprecedented sub-kilometer scales provides the missing link between traditional point-scale sensors and large-scale satellite remote sensing products. In recent years, networks of CRS have been established worldwide but not yet for tropical hydrological studies (e.g., in South America). In addition, limited representation of key hydrological processes (including subsurface-surface interactions) in current Earth System Models poses extreme challenges for prediction and adaptation strategies. This is important for predicting extreme events such as droughts, especially in data scarce regions such as in tropical areas. The recent (2013-2014) extreme drought event that occurred in southeast Brazil severely affected water resources in the region including the Cantareira Reservoir System (one of the largest in the world) which supplies water to more than 9 million people in Sao Paulo metropolitan area. Lack of accurately representing the role of soil moisture in connecting the subsurface to surface water dynamics will continue to undermine our predictability skills, consequently providing sub-optimal information for adaptation strategies in important economic-social region in South America and globally.This opportunity is very timely because it will allow both groups to mutually exploit the hydrological model developments from our current NERC New Investigator "A MUlti-scale Soil moisture - Evapotranspiration Dynamics study" (AMUSED) project using locally available data from an experimental catchment in southeast Brazil which has recently experienced an extreme drought event. This provides a unique opportunity to further evaluate our current model developments (i.e., preferential water flow in soils, and groundwater dynamics) in a challenging tropical region. Also importantly, BEMUSED will allow the UoB to engage in knowledge and skills transfer associated with the use of CRS particularly in a tropical South America region where it has never been tested. A CRS is scheduled to be installed at the experimental catchment in 2018, hence we propose to test our CRS deployment/calibration guidelines and data processing approaches, developed under AMUSED, in tropical South America for the first time, and further engage with AMUSED's original Pathways to Impact activities in promoting knowledge transfer and dissemination of new measurement technology by offering a short-course on "Soil Moisture Measurements using Cosmic-Ray Sensors" in Brazil. Finally, a workshop will be held in Brazil to discuss on strategies for improvement of Brazil's national capability for large-scale hydrometeorological monitoring and modeling with the aim to enhance response to future hydroclimatic variability and natural hazards.