Large artificial lakes and reservoirs affect the meteorological regime of the shore area and the local climate takes on a number of new features that were previously absent. This work focuses on the weather impact of the Alqueva reservoir, the largest artificial lake in Western Europe. An extensive set of numerical simulations using Meso-NH mesoscale atmospheric model coupled with FLake (Freshwater Lake) scheme was carried out. The simulations covered a 12-month period that was chosen to compose a so-called Typical Meteorological Year. This artificial time period is meant to represent the typical meteorological conditions in the region and the model results are used to assess the changes in the local climate. To evaluate the raw impact of the reservoir, two different scenarios of simulations were compared: (A) with the reservoir as it exists nowadays and (B) without the reservoir using the older surface dataset. The results show decrease of air temperature during daytime (10–9°C) and nighttime increase (up to 10°C). In nearest towns, daily maximum temperature decreased and daily minimum temperature increased, which refers to milder weather conditions. Alqueva mainly showed suppression in fog formation in the nearby area. Local breeze regime was studied and monthly lake/land breezes were described.

中文翻译：

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大型人工湖对区域气候的影响：典型气象年Meso-NH模拟结果

大型人工湖和水库影响了海岸地区的气象状况，当地气候呈现出许多以前没有的新特征。这项工作的重点是西欧最大的人工湖 Alqueva 水库对天气的影响。使用 Meso-NH 中尺度大气模型和 FLake（淡水湖）方案进行了大量数值模拟。模拟涵盖了 12 个月的时间段，该时间段被选为所谓的典型气象年。该人工时间段旨在代表该地区的典型气象条件，模型结果用于评估当地气候的变化。为了评估储层的原始影响，比较了两种不同的模拟场景：(A) 使用现在存在的水库，(B) 没有使用旧地表数据集的水库。结果显示白天气温下降（10-9°C），夜间气温升高（高达 10°C）。在最近的城镇，日最高气温下降，日最低气温上升，这是指天气条件温和。Alqueva 主要表现出对附近地区雾形成的抑制。研究了当地的微风状态，并描述了每月的湖/陆微风。Alqueva 主要表现出对附近地区雾形成的抑制。研究了当地的微风状态，并描述了每月的湖/陆微风。Alqueva 主要表现出对附近地区雾形成的抑制。研究了当地的微风状态，并描述了每月的湖/陆微风。