Search

Traditional cooling and heating systems in residential buildings account for more than 15% of global electricity consumption and 10% of global emissions of greenhouse gases. Daytime radiative cooling (DRC) is an emerging passive cooling technology that has garnered significant interest in recent years due to its high cooling capability. It is expected to play a pivotal role in improving indoor and outdoor urban environments by mitigating surface and air temperatures while decreasing relevant energy demand. Yet, DRC is in its infancy, and thus several challenges need to be addressed to establish its efficient wide-scale application into the built environment. In this Perspective, we critically discuss the strategies and progress in materials development to achieve DRC and highlight the challenges and future paths to pave the way for real-life applications. Advances in nanofabrication in combination with the establishment of uniform experimental protocols, both in the laboratory/field and through simulations, are expected to drive economic increases in DRC., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Human comfort outdoors is widely investigated, but most studies explore the comfort domains singularly. This paper aimed to evaluate human comfort in parks, verifying the importance of using a multi-domain (simultaneously evaluating thermal, visual, acoustic, and air quality) and multi-disciplinary (combining environmental and social fields) approach. A walk through a pre-defined path from one park to another was repeated twice per day on four consecutive days in June, with three participants per walk. The two investigated parks are in central Italy and were chosen because they differ in their design and spatial characteristics. Environmental data were recorded with an innovative wearable device during the whole walk, and surveys were used to assess people's perceptions of the parks. Despite observed differences in collected physical parameters, the survey's responses were similar, and different comfort domains showed dependence on each other in the two parks. Logistic regression models were developed for each park, and they revealed that the qualitative information predicted the overall comfort level more accurately than the environmental data. In detail, the models based on environmental data resulted in R 2 equal to 0.126 and 0.111 in Parks 1 and 2, respectively, whereas using the survey answers increased it up to 0.820 (Park 1) and 0.806 (Park 2). This study contributes to addressing the gap in multi-domain comfort studies outdoors and confirms the importance of using multi-disciplinary and multi-domain approaches for a complete comfort analysis, supporting holistic human-biometeorology-oriented models and forecasting opportunities that can promote improvements in urban environmental quality and liveability., (© 2022. The Author(s).)

The sediment record from Lake Ohrid (Southwestern Balkans) represents the longest continuous lake archive in Europe, extending back to 1.36 Ma. We reconstruct the vegetation history based on pollen analysis of the DEEP core to reveal changes in vegetation cover and forest diversity during glacial-interglacial (G-IG) cycles and early basin development. The earliest lake phase saw a significantly different composition rich in relict tree taxa and few herbs. Subsequent establishment of a permanent steppic herb association around 1.2 Ma implies a threshold response to changes in moisture availability and temperature and gradual adjustment of the basin morphology. A change in the character of G-IG cycles during the Early-Middle Pleistocene Transition is reflected in the record by reorganization of the vegetation from obliquity- to eccentricity-paced cycles. Based on a quantitative analysis of tree taxa richness, the first large-scale decline in tree diversity occurred around 0.94 Ma. Subsequent variations in tree richness were largely driven by the amplitude and duration of G-IG cycles. Significant tree richness declines occurred in periods with abundant dry herb associations, pointing to aridity affecting tree population survival. Assessment of long-term legacy effects between global climate and regional vegetation change reveals a significant influence of cool interglacial conditions on subsequent glacial vegetation composition and diversity. This effect is contrary to observations at high latitudes, where glacial intensity is known to control subsequent interglacial vegetation, and the evidence demonstrates that the Lake Ohrid catchment functioned as a refugium for both thermophilous and temperate tree species., Competing Interests: The authors declare no competing interest.

Monitoring microclimate variables within cities with high accuracy is an ongoing challenge for a better urban resilience to climate change. Assessing the intra-urban characteristics of a city is of vital importance for ensuring fine living standards for citizens. Here, a novel mobile microclimate station is applied for monitoring the main microclimatic variables regulating urban and intra-urban environment, as well as directionally monitoring shortwave radiation and illuminance and hence systematically map for the first time the effect of urban surfaces and anthropogenic heat. We performed day-time and night-time monitoring campaigns within a historical city in Italy, characterized by substantial urban structure differentiations. We found significant intra-urban variations concerning variables such as air temperature and shortwave radiation. Moreover, the proposed experimental framework may capture, for the very first time, significant directional variations with respect to shortwave radiation and illuminance across the city at microclimate scale. The presented mobile station represents therefore the key missing piece for exhaustively identifying urban environmental quality, anthropogenic actions, and data driven modelling toward risk and resilience planning. It can be therefore used in combination with satellite data, stable weather station or other mobile stations, e.g. wearable sensing techniques, through a citizens' science approach in smart, livable, and sustainable cities in the near future.

Accurate monitoring is critical for better understanding cities' microclimate conditions and safeguard citizens' health. Previous studies have performed microclimate analyses of urbanized areas by implementing data from either stable meteorological stations or satellites, or by developing mobile stations. Here, we present a vehicle-based monitoring campaign capable of monitoring both the scalar and directionally dependent variables that regulate the canopy layer environment. Under this framework, we performed a monitoring campaign within an Italian city, and measured simultaneously air temperature (±  0.3 ∘ C @ 20 ∘ C ), relative humidity (±  2% @ 20 ∘ C ), directional shortwave radiation (calibration uncertainty: < 1.8%), CO 2 (±  50 ppm +2%) and PM10 (< 1%) concentration, wind speed (±  3% @ 40 m/s) and direction (±  3 ∘ @ 40 m/s), and specific location (latitude, longitude and elevation). The presented assessment can be carried out within almost any area that motorized vehicles are allowed to access (e.g. through public transportation vehicles). Its application together with other mobile stations that can specifically assess also pedestrian areas, such as footpaths, urban parks, sidewalks and bike paths, as well as fixed meteorological stations and remote sensing techniques can contribute to a better understanding of microclimate patterns and hence to more efficient urban planning and risk assessments., (© University of Tehran 2021.)

Mediterranean climates are characterized by strong seasonal contrasts between dry summers and wet winters. Changes in winter rainfall are critical for regional socioeconomic development, but are difficult to simulate accurately 1 and reconstruct on Quaternary timescales. This is partly because regional hydroclimate records that cover multiple glacial-interglacial cycles 2,3 with different orbital geometries, global ice volume and atmospheric greenhouse gas concentrations are scarce. Moreover, the underlying mechanisms of change and their persistence remain unexplored. Here we show that, over the past 1.36 million years, wet winters in the northcentral Mediterranean tend to occur with high contrasts in local, seasonal insolation and a vigorous African summer monsoon. Our proxy time series from Lake Ohrid on the Balkan Peninsula, together with a 784,000-year transient climate model hindcast, suggest that increased sea surface temperatures amplify local cyclone development and refuel North Atlantic low-pressure systems that enter the Mediterranean during phases of low continental ice volume and high concentrations of atmospheric greenhouse gases. A comparison with modern reanalysis data shows that current drivers of the amount of rainfall in the Mediterranean share some similarities to those that drive the reconstructed increases in precipitation. Our data cover multiple insolation maxima and are therefore an important benchmark for testing climate model performance.