The ice‐nucleating particles (INPs) modulate the microphysics and radiative properties of clouds. However, less is known concerning their abundance and sources in the most pristine and climatic sensitive regions, such as the Tibetan Plateau (TP). Here, to our best knowledge, we conduct the first investigation on INPs in rainwater collected in the TP region under mixed‐phase cloud conditions. The value of INP concentrations varies from 0.002 to 0.675 L⁻¹ air over the temperature range from −7.1 to −27.5°C. This is within the INP spectra derived from precipitation under worldwide geophysical conditions and is also comparable with INP concentrations in the Arctic regions. The heat‐sensitive INPs account for 57% ± 30% of the observed INPs at −20°C and become increasingly important at higher temperatures, indicating biological particles as major contributors to INPs at temperatures above −20°C over the TP, especially on the day with additional input of biogenic materials carried by dust particles. Chemical analysis demonstrates that the rainwater components are mixture of dust particles, marine aerosol, and anthropogenic pollutants. Combined with the backward trajectory analysis, we show that dust particles transported from the surrounding deserts and originated from ground surface of TP may contribute to the heat‐resistant INPs at temperatures below −20°C.

中文翻译：

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青藏高原第三极雨水中的冰核颗粒浓度及其来源

冰核颗粒（INPs）调节云的微观物理和辐射特性。然而，在最原始和气候敏感的地区，如青藏高原（TP），关于它们的丰度和来源的信息鲜为人知。在这里，据我们所知，我们对混合相云条件下TP地区收集的雨水中的INPs进行了首次调查。INP浓度的值在0.002至0.675 L ^{-1之间变化}空气在-7.1至-27.5°C的温度范围内。这是在全球地球物理条件下从降水获得的INP光谱之内，也可与北极地区的INP浓度相媲美。在-20°C时，热敏性INP占所观察到的INPs的57％±30％，并且在较高温度下变得越来越重要，表明在TP上，在高于-20°C的温度下，生物颗粒是INPs的主要贡献者，特别是在TP上。一天中，灰尘颗粒携带的生物材料的投入也增加了。化学分析表明，雨水成分是灰尘颗粒，海洋气溶胶和人为污染物的混合物。结合向后轨迹分析，