COVID‐19 is spreading rapidly worldwide, posing great threats to public health and economy. This study aims to examine how the transmission of COVID‐19 is modulated by climate conditions, which is of great importance for better understanding of the seasonal feature of COVID‐19. Constrained by the accurate observations we can make, the basic reproduction numbers (R₀) for each country were inferred and linked to temperature and relative humidity (RH) with statistical analysis. Using R₀ as the measure of COVID‐19 transmission potential, we find stronger transmission of COVID‐19 under mildly warm (0°C < T < 20°C) and humid (RH > 60%) climate conditions, while extremely low (T < −2°C) and high (T > 20°C) temperature or a dry climate (RH < 60%) weakens transmission. The established nonlinear relationships between COVID‐19 transmission and climate conditions suggest that seasonal climate variability may affect the spread and severity of COVID‐19 infection, and temperate coastal regions with mildly warm and humid climate would be susceptible to large‐scale outbreaks.

中文翻译：

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气候条件对COVID-19传播的非线性调制

COVID-19正在全球范围内迅速传播，对公共卫生和经济构成了巨大威胁。这项研究旨在研究气候条件如何调节COVID-19的传播，这对于更好地了解COVID-19的季节特征非常重要。受我们能提供的准确观察结果的限制，可以推断每个国家的基本繁殖数量（R ₀），并通过统计分析将其与温度和相对湿度（RH）关联起来。使用R ₀作为COVID-19传播潜力的量度，我们发现在温和的（0°C < T <20°C）和潮湿（RH> 60％）的气候条件下，而在极低的（T <−2°C）和高（T温度> 20°C）或干燥气候（RH <60％）会削弱传播。COVID-19传播与气候条件之间已建立的非线性关系表明，季节性气候变化可能会影响COVID-19感染的传播和严重程度，温和湿润气候的温带沿海地区可能会大规模爆发。