Flood-Inducing Atmospheric and Antecedent Conditions: Variation and Change Across the UK and Europe

该项目的目的是确定极端的诱导洪水的大气模式（以及之前的条件），并了解它们在空间上（跨越英国和欧洲不同的水文气候）和时间上（过去和未来几十年）的变化。这项工作还将确定导致不同类型洪水事件的这些驱动因素的最坏情况，以及这种关系如何在空间和时间上变化。洪水对整个英国和欧洲的社会经济和环境都有严重的影响。它们也可能导致生命损失。2021年，比利时和德国的洪水造成约200人死亡。2022年，英国的尤妮斯风暴被认为是几十年来最严重的风暴，导致全国各地发生严重洪灾，交通中断，基础设施受损（Fekete & Sandholz, 2021; Met Office, 2022）。政府间气候变化专门委员会还警告说，随着气温进一步升高，未来洪水事件可能造成的破坏可能是毁灭性的、不可逆转的。因此，了解洪水变率和洪水诱因的研究对于减缓措施至关重要，因为气候变化将加剧水文循环并导致更多极端事件（IPCC, 2022; Pattinson & Lane, 2011; Wilby & Quinn, 2013）。据预测，随着气候变化，未来英国和欧洲的洪水频率和强度将会增加。然而，这一变化及其在时间和空间上的分布尚不清楚，并将因区域先决条件和水文气候而异。此外，洪水将根据季节和年代际变化而变化。历史上的古气候研究表明，洪水丰富的时期发生在寒冷的天气，而其他当代研究表明，由于大气含水量升高，洪水将随着全球气温升高而增加。虽然随着气温的升高，降水将会增加，因为大气可以容纳更多的水，但这是否会转化为洪水还不太清楚（Bronnimann et al, 2022; Met Office, 2022; Stucki et al, 2012）。因此，了解诱发洪水事件的大气条件和先前条件之间的历史和当前关系非常重要，这样可以使基于温度升高和大气含水量的未来预测更加准确。也缺乏证据表明，过去两个世纪的洪水状况变化与人为气候变化有关，对未来的预测也不完全清楚和准确（Bronnimann et al, 2022）。洪水频率和强度的变化取决于许多不同的诱因，如大气和先决条件（Nied等，2014）。在我的项目中，我将研究英国和欧洲不同水文气候中不同类型的洪水事件与这些诱因之间的关系。将研究这种关系在不同时间尺度（如亚季节和年代际）上的变率。这个DTP项目将着眼于分类大气模式（AOPP子部门），并使用先例和水文数据（SoGE部门）来研究这些驱动因素如何在英国和欧洲的时间和空间上诱发不同的洪水类型事件（来自牛津大学和弗莱堡大学的主管）。迄今为止，诱导洪水事件的大气和先决条件的相对重要性以及它们如何随气候变化而变化尚不清楚。了解这些变量在未来可能发生的变化也很重要。在个别气象变量尺度上，还将考虑变温、降水和洪水事件之间的关系，以弥补这一研究空白。这个项目是跨学科的，需要了解大气和水圈（因此要求AOPP的访问身份）。

The aim of this project is to identify extreme flood-inducing atmospheric patterns (and antecedent conditions) and understand how they vary both spatially (across different hydroclimates in the UK and Europe) and temporally (over past and future decades). The work will also identify the worse-case scenario of these driver for inducing different types of flood events and how this relationship varies spatially and temporally.Floods have severe socioeconomic and environmental impacts across the UK and Europe. They also can result in loss of life. During 2021, flooding across Belgium and Germany killed an estimated 200 people. In 2022, Storm Eunice in the UK was labelled the most severe storm in decades, resulting in severe flooding across the country which disrupted transport links and damaged infrastructure (Fekete & Sandholz, 2021; Met Office, 2022). The IPCC has also warned that with further increase in temperatures, the damage that future flood events could have may be devastating and irreversible. Research intounderstanding flood variability and flood inducers if therefore vital for mitigation measures as climate change is set to intensify the hydrological cycle and result in more extreme events (IPCC, 2022; Pattinson & Lane, 2011; Wilby & Quinn, 2013). Flood frequency and intensity is projected to increase into the future as the climate changes, across the UK and Europe. The variability and distribution temporally and spatially of this, however, is not clearly understood and will differ depending on regional antecedent conditions and hydroclimates. Furthermore, floods will vary depending on seasonal and decadal variability. Historical paleoclimate studies suggest that flood-rich periods occurred during cold weather, whilst other contemporary studies suggest that floods will increase as global temperature increase, due to elevated atmospheric water content. Although as temperatures increase, precipitation is set to increase as the atmosphere can hold more water, whether this translates into floodevents is less clear (Bronnimann et al, 2022; Met Office, 2022; Stucki et al, 2012). It is therefore important to understand the historical and current relationship between atmospheric and antecedent conditions for inducing flood events, so that future projections based on increasing temperatures and atmospheric water content can be made more accurate. There is also a lack of evidence to suggest that the changes in flood regimes over the last two centuries are linked to anthropogenic climate change, and future projections are not fully clear and accurate (Bronnimann et al, 2022).Changes in flood frequency and intensity are dependent on a multitude of different inducers, such as atmospheric and antecedent conditions (Nied et al, 2014). In my project I will study the relationship between different types of flood events and these inducers across varying hydroclimates in the UK and Europe will be studied in this project. The variability of this relationship on different temporal scales such as the sub -seasonal and decadal will be studied. This DTP project will look at classifying atmospheric patterns (AOPP subdepartment) and use antecedent and hydrological data (SoGE department) to study how these drivers induced different flood type events over time and space across the UK and Europe (Supervisors from Oxford and University of Freiburg). To date, the relative importance ofatmospheric and antecedent conditions inducing flood events and how this may change with climate change is unclear. It is also important to understand how these variables could potentially change into the future. The relationship between the variable temperature, precipitation and flood events will also be considered at the individual meteorological variable scale to contribute to this research gap. This project is interdisciplinary and will require the understanding of the atmosphere and hydrosphere (hence the request for visiting status at AOPP).