PAR009 Optical disdrometer data at Lutjewad

<strong>Description:</strong> In-situ measurements of raindrop size distributions, fall velocities, drop number concentrations and surface rain rates recorded by an OTT Parsivel2 disdrometer named "PAR009" at a height of 3 meters at the Lutjewad atmospheric measurement station on the northern coast of the Netherlands, approximately 30 km northeast from the city of Groningen. "PAR009_Lutjewad" replaces "PAR008_Lutjewad" which was damaged on April 7, 2022 during a storm. The rural landscape to the south consists mainly of pasture and cropland with patches of forested land with livestock dominated by dairy cows and sheep. Set up directly behind the Wadden Sea dike, the site features a 60 meter tall sampling tower, a 10 meter platform, a laboratory building, and an aerosol laboratory container. The station monitors greenhouse gases and trace gas species, sampling aerosol number, size, and composition at different altitudes. Lutjewad is part of the European research infrastructure ICOS, providing continuous greenhouse gas concentrations. The coastal location means that the site samples relatively clean marine background air in conditions of northerly winds and more polluted air masses during conditions of south-easterly and south-westerly winds.<br><strong>Format:</strong> Each NetCDF file covers a full month of observations. The temporal resolution is 1 minute. Data are provided "as is", without any post-processing. The NetCDF files contain all relevant information about all the variables, attributes and units. The global attributes of the NetCDF files contain important information about the type of sensor, logging software, project contributors and history of the dataset. If a monthly file is missing, no data are available for this month.<br><strong>Relevance:</strong> Optical disdrometer data are useful for studying the type, dynamics and microphysics of precipitation from the perspective of a fixed observer on the ground. The data can be used to help calibrate weather radars, improve quantitative precipitation estimates, calculate the absorption/attenuation/propagation of electromagnetic signals through the atmosphere, and quantify important physical quantities such as liquid water content, rain amount, intensity and kinetic energy.<br><strong>Note:</strong> This dataset is updated approximately every 3 months. Please reach out to the authors if you wish to get access to the most recent data.<br><strong>Known issues:</strong>Due to a sensor malfunction, the internal temperature values between November 2024 and February 2025 cannot be trusted. We hope to be able to fix this issue soon.

<strong>数据集描述：</strong>本数据集包含由名为"PAR009"的OTT Parsivel2雨滴谱仪（disdrometer）在荷兰北海岸吕特耶瓦德（Lutjewad）大气观测站3米高度处采集的原位观测数据，观测内容包括雨滴尺寸分布、下落末速度、雨滴数浓度与地表降雨率。该观测站距离格罗宁根市东北约30公里。原设备"PAR008_Lutjewad"于2022年4月7日在风暴中受损，故由"PAR009_Lutjewad"接替。观测站南侧为乡村景观，以牧场和农田为主，夹杂小片林地，牲畜以奶牛和绵羊为主。该站紧邻瓦登海海堤布设，配套建有60米高采样塔、10米观测平台、实验室大楼及气溶胶实验室集装箱。观测站同时监测温室气体与痕量气体组分，可在不同海拔采集气溶胶的数量、粒径与组成数据。吕特耶瓦德站是欧洲研究基础设施ICOS的组成部分，可连续监测温室气体浓度。由于地处沿海，该站点在北风条件下采集相对洁净的海洋背景大气，而在东南风与西南风条件下则会受到污染气团的影响。<br><strong>数据格式：</strong>每个NetCDF文件涵盖完整一个月的观测数据，时间分辨率为1分钟。数据按"现状"提供，未经过任何后处理。NetCDF文件包含所有变量、属性与单位的相关信息。NetCDF文件的全局属性中记录了传感器类型、采集软件、项目贡献者及数据集历史等关键信息。若某月度文件缺失，则代表该月无可用观测数据。<br><strong>应用价值：</strong>地面固定式观测的雨滴谱仪数据可用于研究降水的类型、动力学特征与微物理过程。该数据可用于辅助气象雷达校准、提升定量降水估测精度、计算电磁信号在大气中的吸收/衰减/传播特性，以及量化液态水含量、降雨量、降雨强度与动能等关键物理量。<br><strong>注意事项：</strong>本数据集约每3个月更新一次。若需获取最新数据，请联系数据集作者。<br><strong>已知问题：</strong>由于传感器故障，2024年11月至2025年2月期间的内部温度数据不可靠。我们计划尽快修复该问题。