Data from: Export of ice nucleating particles from a watershed

Ice nucleating particles (INP) active at a few degrees below 0°C are produced by a range of organisms and released into the environment. They may affect cloud properties and precipitation when becoming airborne. So far, our knowledge about sources of biological INP is based on grab samples of vegetation, soil or water studied in the laboratory. By combining measurements of INP concentrations in river water with river water discharge rates over the course of 16 months, we obtained a lower limit for the production rate of INP in a watershed covering most of Switzerland (4 × 105 INP−8 m−2 d−1). Coincidentally, we found that INP−8 are likely to retain their potential for catalysing ice formation in the natural environment for at least several months before they are mobilized by an intensive rainfall, washed into the river and exported from the watershed.

在低于0℃数摄氏度下具有活性的冰核粒子（Ice Nucleating Particles，INP）由多种生物体产生并释放至自然环境中。当其进入大气后，可能会对云特性及降水过程产生影响。迄今为止，学界关于生物源INP的认知均基于实验室中对植被、土壤或水体的瞬时采样。本研究通过将16个月内河水的INP浓度监测数据与河流径流量数据相结合，得到了覆盖瑞士大部分区域的流域内，-8℃活性INP生成速率的下限值（4×10^5 m^-2·d^-1）。值得注意的是，本研究发现，-8℃活性INP在自然环境中可至少保留其催化冰晶形成的潜能长达数月，直至被强降雨触发、冲刷进入河流并从流域输出。