Because of climate change, heat waves (HWs) and droughts are projected to become more frequent, more intense and more persistent. A detailed analysis of the complex processes is needed to understand the relationship between the urban heat island (UHI) phenomenon and HWs. In this study, we investigated how HWs affect the surface UHI (SUHI) in Budapest. We used 22-year-long time series of MODIS measurements to investigate the SUHI patterns, surface temperature and humidity in detail. A significant warming trend was detected in both the morning and afternoon surface temperature data series over the past decades, with a warming rate of 0.8–2.2 °C/decade. Moreover, as the rural surroundings of the urban area become warmer in summer, the SUHI intensity weakens, especially in July and August, which is related to the less moisture available in the rural area and hence becoming unable to reduce the surface temperature, similarly to the urban area. In the years with frequent HWs and droughts, SUHI does not develop since both the urban and rural areas are characterised by extremely high land surface temperature. This phenomenon is investigated and compared in detail for the years 2003, 2007 and 2022 when intense HWs occurred in the region.

中文翻译：

---

热浪和干旱期间布达佩斯的地表城市热岛——2003年、2007年和2022年夏季的比较

由于气候变化，热浪 (HW) 和干旱预计将变得更加频繁、更加强烈和持久。需要对复杂过程进行详细分析，以了解城市热岛 (UHI) 现象与 HW 之间的关系。在这项研究中，我们研究了硬水如何影响布达佩斯的地表城市热岛 (SUHI)。我们使用 MODIS 长达 22 年的时间序列测量来详细研究 SUHI 模式、地表温度和湿度。过去几十年的早晨和下午地表温度数据系列均检测到显着的变暖趋势，变暖速率为0.8-2.2°C/十年。此外，夏季，随着城市农村地区变暖，SUHI强度减弱，特别是在7、8月份，这与农村地区可利用的水分较少，无法降低地表温度有关，类似于市区。在水灾和干旱频繁的年份，由于城市和农村地区地表温度极高，因此SUHI不发展。我们对 2003 年、2007 年和 2022 年该地区发生强烈 HW 的情况进行了详细调查和比较。