The understanding of intra-urban air temperature variations is crucial to assess strategies for cities' adaptation to impacts of present and future anthropogenic climate change. Depending on extensive measurement networks, high-resolution air temperature measurements in urban environments are challenging due to high instrumentation and maintenance costs. Here, we present a low-cost measurement device (LCD) consisting of a temperature logger and a custom-made, naturally ventilated radiation shield. Besides intercomparisons with automated weather stations (AWS) at three reference sites during record-dry summer 2018, we tested the potential of the devices using a network of 79 LCDs to assess the intra-urban variability of urban heat island (UHI) patterns in the city of Bern, Switzerland. We found positive mean measurement biases between LCDs and AWS of 0.61 to 0.93 K (RMSE: 0.78 to 1.17 K) during daytime, of which up to 82.8% of the variance could be explained statistically by solar irradiance (radiative heating) and wind speed (insufficient ventilation). During night, average measurement biases were markedly lower and eventually negative with −0.12 to 0.23 K (RMSE: 0.19 to 0.34 K). Our results highlight the importance of sensor intercomparisons being conducted at multiple locations with differing urban land-cover, structure, and metabolism given that biases varied considerably between the reference sites. Data retrieved by the city-wide measurement network showed that the LCD approach is well suited for the analysis of spatiotemporal UHI patterns during night and adds considerable value compared to the few existing AWS in detecting fine-scale air temperature variability. In conclusion, the current LCD measurement approach represents a valuable option for cost-effective analyses of urban air temperature variability across multiple scales, which may be of particular value for the development, appliance, and monitoring of adaptation strategies to climate change in cities with restricted financial resources.

了解城市内部气温变化对于评估城市适应当前和未来人为气候变化影响的策略至关重要。依赖于广泛的测量网络，由于高昂的仪器和维护成本，在城市环境中进行高分辨率空气温度测量具有挑战性。在这里，我们介绍了一种由温度记录器和定制的自然通风的辐射防护屏组成的低成本测量设备（LCD）。除了在2018年创纪录的夏季与三个参考站点的自动气象站（AWS）进行比对之外，我们还使用79个LCD屏幕网络测试了设备的潜力，以评估城市热岛（UHI）模式的城市内部变异性。瑞士伯尔尼市。我们发现白天LCD和AWS之间的正平均测量偏差为0.61至0.93 K（RMSE：0.78至1.17 K），其中最多82.8％的方差可以用太阳辐照度（辐射加热）和风速进行统计学解释（通风不足）。在夜间，平均测量偏差明显降低，最终为负值，为-0.12至0.23 K（RMSE：0.19至0.34 K）。我们的结果凸显了传感器比对的重要性，因为参考地点之间的偏差存在很大差异，因此必须在具有不同城市土地覆盖，结构和新陈代谢的多个地点进行传感器比对。通过全市范围的测量网络获得的数据表明，LCD方法非常适合于夜间时空UHI模式的分析，与现有的少数AWS相比，LCD方法在检测细微的气温变化方面具有可观的价值。总之，当前的LCD测量方法是一种经济有效的分析方法，可用于跨尺度的城市空气温度变异性的经济高效分析，这对于开发，应用和监测受限城市的气候变化适应策略可能具有特殊价值。金融资源。