Abstract Long, continuously-gaged precipitation records are needed for characterizing extreme rainfall events over sub-daily durations, as well as detecting potential historical effects of climate change. However, most such records predating the 1980s are in the form of paper strip charts (pluviograms), from which it is notoriously difficult to extract extreme precipitation depths for short durations (from a few minutes to a few hours). We propose a highly accurate method for digitizing weekly strip charts from float and siphon pluviographs and obtaining continuous rainfall data from them. The method’s main inputs are the digital image of a strip chart and its recording time window (typically one day or one week). With this data, the software sequentially performs four processes: (1) it identifies the ink-traced line in the digital image, (2) it joins any separated segments of the line and removes elements that are not part of it, (3) it defines the line in Cartesian coordinates, and (4) it converts the defined line into precipitation values. The method has been implemented in the PluvioReader software, with a friendly and intuitive user interface that allows for easy handling of inputs and outputs, and includes basic image editing tools. The PluvioReader software has been tested on more than 800 weekly strip charts from several stations in Chile, successfully extracting precipitation series down to a 5-min resolution, even from complex pluviograms with multiple drainage events and steep lines.

中文翻译：

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PluvioReader：用于数字化每周虹吸式雨量计条形图的软件

摘要 需要长时间、连续监测的降水记录来表征亚日持续时间的极端降雨事件，以及检测气候变化的潜在历史影响。然而，1980 年代之前的大多数此类记录都采用纸质条形图（雨量图）的形式，众所周知，很难从中提取短时间（从几分钟到几小时）的极端降水深度。我们提出了一种高度准确的方法，用于将浮式和虹吸式雨量记录仪的每周带状图数字化，并从中获取连续降雨数据。该方法的主要输入是带状图的数字图像及其记录时间窗口（通常为一天或一周）。有了这些数据，软件会依次执行四个过程：(1) 识别数字图像中的墨迹线，(2) 它连接线的任何分离段并删除不属于它的元素，(3) 它在笛卡尔坐标中定义线，以及 (4) 它将定义的线转换为降水值。该方法已在 PluvioReader 软件中实施，具有友好直观的用户界面，可以轻松处理输入和输出，并包括基本的图像编辑工具。PluvioReader 软件已经在来自智利多个站点的 800 多个每周条形图上进行了测试，即使从具有多个排水事件和陡峭线的复杂雨量图也成功提取了分辨率低至 5 分钟的降水序列。(4) 将定义的线转换为降水值。该方法已在 PluvioReader 软件中实施，具有友好直观的用户界面，可以轻松处理输入和输出，并包括基本的图像编辑工具。PluvioReader 软件已经在来自智利多个站点的 800 多个每周条形图上进行了测试，即使从具有多个排水事件和陡峭线的复杂雨量图也成功提取了分辨率低至 5 分钟的降水序列。(4) 将定义的线转换为降水值。该方法已在 PluvioReader 软件中实施，具有友好直观的用户界面，可以轻松处理输入和输出，并包括基本的图像编辑工具。PluvioReader 软件已经在来自智利多个站点的 800 多个每周条形图上进行了测试，即使从具有多个排水事件和陡峭线的复杂雨量图也成功提取了分辨率低至 5 分钟的降水序列。