The “Applied Simulations and Integrated Modelling for the Understanding of Harmful Algal Blooms” (Asimuth) project sought to develop a harmful algal bloom (HAB) alert system for Atlantic Europe. This was approached by combining, at a national or regional level, regulatory monitoring phytoplankton and biotoxin data with satellite remote sensing and other information on current marine conditions, coupled with regional scale models that included a representation of HAB transport. Synthesis of these products was achieved by expert interpretation within HAB risk alert bulletins that were prepared on a regular basis (typically weekly) for use by the aquaculture industry. In this preface to the Asimuth Special Issue we outline the main HAB species of concern in the region and the strengths and limitations of different methodologies to provide early warning of their blooms.

“了解有害藻华的应用模拟和集成建模”（Asimuth）项目旨在为大西洋欧洲开发有害藻华（HAB）警报系统。为此，在国家或区域层面将浮游植物和生物毒素的监管监测数据与卫星遥感和有关当前海洋状况的其他信息相结合，并结合包括HAB迁移代表在内的区域尺度模型。这些产品的合成是通过定期（通常每周）准备供水产养殖业使用的 HAB 风险警报公告中的专家解释实现的。在 Asimuth 特刊的前言中，我们概述了该地区值得关注的主要 HAB 物种，以及提供其藻华早期预警的不同方法的优点和局限性。