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Graphical abstract Urban Heat Island in China. Highlights • It is the first quantitative analysis of spatial–temporal patterns of UHI in China. • UHI has linearly increased from 1984 to 2013 and is strongest in summer. • Arid inland and mountainous areas had higher UHI compared to other areas. • The spatial patterns of UHI in China mainly related to natural factors. Abstract Urban heat islands (UHIs) have very large negative effects on local climate features and ecological environments. However, the larger-scale temporal and spatial patterns of UHIs are still unclear. Our research explored the large-scale spatial and temporal patterns of UHIs in 155 cities across China by collecting observational data from 310 meteorological stations over a 30-year period (1984–2013). The results suggested that the UHI intensity has linearly increased over the past 30 years and is strongest in summer across different years. The UHI intensity in inland cities is significantly higher than that in coastal cities; cities in arid areas had higher UHI intensities than those in humid areas; cities in middle or high mountain areas had higher UHI intensities compared to those located in the other landforms in China. There are no significant differences in UHI intensity between cities located in different climatic zones or between cities with different GDP levels, population sizes and industrial structures. Additionally, the relationships between the UHI intensity and several factors, such as meteorological conditions, GDP level and population size, were analyzed. Our results showed that average wind speed, average precipitation and relative humidity had a significant negative correlations with UHI intensity, whereas there was no significant correlation between anthropogenic factors and UHI intensity. Our research indicated that we should consider the local climate and landscape to eliminate UHI hazards in the future urbanization processes. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) are the major conservation tool for ecosystem conservation, but function unequally in mitigating human pressures in practice. Assessing PA vulnerability caused by human pressures and its association with socioeconomic and PA characteristic factors is vital for improving conservation effectiveness and the post-2020 PA expansion. Here, using a new framework integrating the intensity and temporal changes of human pressures in PAs and their matched unprotected areas, we categorize global terrestrial PAs into four anthropogenic vulnerability levels: high (11.7 %), moderate (18.6 %) and low (21.9 %) vulnerability and wilderness (47.8 %). We find significant variations in the anthropogenic vulnerability of PAs between countries, continents, and IUCN categories. Europe has the highest proportion of high-vulnerability PAs (ca. 19.7 % of protected areas in Europe), while South America and Oceania have the highest proportions of low-vulnerability PAs and wilderness PAs, respectively (33.2 % and 75.0 % respectively). The vulnerability of PAs is not significantly associated with socioeconomic factors at the country level, which might reflect the trade-offs between positive and negative outcomes of development. With a new framework that integrated four significant factors for anthropogenic vulnerability assessment, this study demonstrates that global PAs have different anthropogenic vulnerability levels and suggest that some PAs function effectively in mitigating human pressures despite currently intense human pressures within them. Our results also suggest that future evaluations on the conservation status should pay attention not only to PA coverage but also to the anthropogenic vulnerability levels within PAs to achieve higher conservation effectiveness. [ABSTRACT FROM AUTHOR]