AMMA-2050 NEC05274

西非的气候受到世界上观测到的最多变的降雨模式的影响。过去，该地区遭受了几十年的严重干旱，而最近的重大洪水事件袭击了该地区许多快速扩张的城市。由于普遍和严重的贫困，这些极端气候对人口的影响特别明显。全球气候变化，加上这种多变和不可预测的区域气候，对西非的人口和经济构成了重大威胁。尽管西非从气候变化到人类苦难的道路很短，但利用气候预测来减轻对人口的风险存在一些关键瓶颈。在关于西非气候在21世纪将如何变化的知识方面存在着严重的差距，而这些不确定性使得各机构几乎不可能在粮食安全、城市发展和水等关键领域为未来几十年制定明智的计划。即使有最好的气候信息，将科学知识纳入规划和管理结构仍然是一个重大挑战。西非和欧洲的科学家和决策者之间的这个合作项目一方面将增进对区域气候及其变化方式的了解，另一方面将把这些知识应用于实际的发展问题。气候科学面临的主要挑战之一是了解大气成分（尤其是二氧化碳）的变化将如何影响洪水和干旱等极端事件的频率和强度。在西非，这些事件与对流暴雨的行为有关；当风暴特别强烈或快速连续发生时，可能会导致毁灭性的洪水，而在雨季一两个星期没有风暴可能会导致作物歉收。气候科学家依靠计算机模拟全球大气、海洋和大陆，然而这些模型对对流风暴的描述非常粗糙。第一次，新一代的区域气候模式正在出现，这些模式真实地描绘了风暴，并且至关重要的是，风暴如何对陆地和海洋条件以及二氧化碳增加等因素作出反应。AMMA-2050将利用这些新的计算机模拟与传统气候模型和历史观测相结合，来理解为什么关键极端气候的统计数据正在发生变化，以及这告诉我们未来几十年气候及其极端气候的什么信息。这些模型的产出将用于检查对西非社会关键部门的影响，特别是水和农业。将探索适应方案，例如通过使用替代作物，同时考虑到气候信息固有的不确定性以及决策者解释气候信息的方式。我们将集中讨论两个问题。首先，在塞内加尔，我们将确定可持续农业适应战略和支持这些选择的政策框架。其次，我们将研究气候变化如何可能影响布基纳法索快速发展的瓦加杜古城市的洪水。AMMA-2050的研究和能力建设工作将有助于培养新一代非洲科学家和决策者，他们有能力对西非国家的需求作出反应。在《AMMA-2050》中，最终用户发挥着重要作用，他们的需求融入到项目设计和实施中，以便产出能够满足他们的需求，并以易于使用的形式提供。增强适应能力是该项目的一个重要目标：它从提高我们对西非气候信号的理解开始，引导我们在具体的试点研究中做出决定，这些研究显示了使用改进的、对影响敏感的科学产出的重要性。

The climate of West Africa is subject to some of the most variable rainfall patterns observed anywhere in the world. In the past, the region has suffered several decades of severe droughts, whilst more recently major flood events have struck a number of the region's rapidly expanding cities. The consequences of these climatic extremes for the population have been particularly pronounced due to widespread and severe poverty. Global climate change, coming on top of such a variable and unpredictable regional climate, poses a major threat to the populations and economies of West Africa. Although the pathway from climate change to human suffering in West Africa is very short, there are some key bottlenecks to using climate projections to mitigate against risks to the population. Critical gaps exist in knowledge of how West African climate will change over the course of the 21st century, and the uncertainties make it almost impossible for agencies to deliver well-informed plans for the coming decades in critical areas such as food security, urban development and water. Even with the best climate information, it remains a significant challenge to integrate the scientific knowledge into planning and management structures. This collaborative project between scientists and policy makers in West Africa and Europe will, on the one hand, increase understanding of the regional climate and how it will change, and on the other, apply that knowledge to practical development questions.One of the key challenges for climate science is to understand how the changing composition of the atmosphere (notably CO2) will impact on the frequency and intensity of extreme events such as floods and droughts. In West Africa, these events are tied to the behaviour of convective rain storms; when storms are particularly intense or occur in rapid succession, devastating floods may result, whilst a week or two without storms during the wet season can trigger crop failure. Climate scientists rely on computer simulations of the global atmosphere, oceans and continents, yet these models have a very crude description of convective storms. For the first time, a new generation of regional climate models is emerging which realistically depict storms, and critically, how storms respond to factors such as land and ocean conditions, and increases in CO2. AMMA-2050 will use these new computer simulations alongside conventional climate models and historical observations, to understand why the statistics of key climate extremes are changing, and what this tells us about climate and its extremes in future decades. The outputs from the models will be used to examine impacts on key sectors in West African society, notably water and agriculture. Adaptation options will be explored, for example through the use of alternative crops, taking account of the inherent uncertainties in climate information, and the ways in which it is interpreted by decision-makers. We will focus on two questions. Firstly, in Senegal we will identify sustainable agricultural adaptation strategies and the policy frameworks to support those options. Secondly, we will examine how climate changes are likely to affect flooding in the rapidly growing city of Ouagadougou in Burkina Faso. The research and capacity building work of AMMA-2050 will help develop a new generation of African researchers and decision-makers, well-placed to respond to the requirements of West African nations. Within AMMA-2050, end-users have an important role, and their needs are embedded in project design and delivery, such that outputs will be responsive to their needs, and delivered in a format that is easily used. Enhanced resilience is an important aim of the project: it starts with improving our understanding of the climate signal over West Africa and leads through to decisions being made in specific pilot studies that showcase the importance of using improved and impact-sensitive science outputs.