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The behaviour of traditional roofs affects issues relating to sustainability, zero-carbon targets, and Urban Heat Island (UHI) effect. This paper discusses an innovative approach towards understanding the behaviour of porous, and other types, of roofs in Malta in relation to temperature and moisture characteristics, and to project this behaviour onto a changing climate, predicted to be hotter and drier. The new methodology is being trialled on four roof types, on historic buildings, the innovation being the use of data from co-temporal Earth Observations (EO) and Unmanned Aerial Vehicles (UAVs), in conjunction with in-situ data. This research is helping to develop a new application for Remote Sensing in Cultural Heritage; results should enable recommendations for sustainable use of traditional roof-building techniques. The initial results show that the traditional roof has different (reflective and emissive) properties from the hybrid roof, that are being detected from space, complemented with UAV, hand-held thermal camera and in-situ measurements. These results are preliminary; satellite images for spring/early summer and mid-summer and the corresponding UAV images are expected to provide more conclusive information. These promising results should enable the proof-of-concept to progress onto a larger number and greater variety of roof types, even in other Mediterranean countries. [ABSTRACT FROM AUTHOR]

This study focuses on a relatively unexplored area located some 33.4 geodetic km away from the central floor of Euclides, in the NE direction, precisely at −6.62° Latitude and −29.89° Longitude. Land-based CCD observations of this area showed a small group of dome-like structures situated on an elevated basaltic platform. One hypothesis is that these features represent a series of mounds made up of a collection of undifferentiated crater materials or ejecta as described by USGS (Geologic Atlas of the Moon. Department of Interior, US Geological Survey-I-458, ). This hypothesis is tested against an alternative one in that the area shows the presence of domes that are partly covered by these ejecta. The present spectrometric results place the basalt within the chosen AOI subset in the low-Ti category (1-5 wt% TiO) and a FeO abundance wt% of between 12 and 14. Spectrometrically, similar dome features have been observed by other investigators near the Milichus/Tobias Mayer regions. A possible classification for this feature would be DW/1a/6h/8j. Details of the cluster analysis used for raster classification is presented as an effective approach to discriminate between different classes of the lunar surface. This approach was used to map the lunar soil geology over the selected showing better lunar geological information than the current mapping information available by USGS. This same approach can be used to effectively map out other regions of the lunar surface. [ABSTRACT FROM AUTHOR]

Background: The effect of ambient temperature on respiratory mortality has been consistently observed throughout the world under different climate change scenarios. Countries experiencing greater inter-annual variability in winter temperatures (and may not be lowest winter temperatures) have greater excess winter mortality compared to countries with colder winters. This study investigates the association between temperature and respiratory deaths in Malta which has one of the highest population densities in the world with a climate that is very hot in summer and mild in winter.Methods: Daily number of respiratory deaths (7679 deaths) and meteorological data (daily average temperature, daily average humidity) were obtained from January 1992 to December 2017. The hot and cold effects were estimated at different temperatures using distributed lag non-linear models (DLNM) with a Poisson distribution, controlling for time trend, relative humidity and holidays. The reference temperature (MMT) for the minimum response-exposure relationship was estimated and the harvesting effects of daily temperature (0-27 lag days) were investigated for daily respiratory mortality. Effects were also explored for different age groups, gender and time periods.Results: Cooler temperatures (8-15 °C) were significantly related to higher respiratory mortality. At 8.9 °C (1st percentile), the overall effect of daily mean temperature was related to respiratory deaths (RR 2.24, 95%CI 1.10-4.54). These effects were also found for males (95%CI 1.06-7.77) and males across different age groups (Males Over 65 years: RR 4.85, 95%CI 2.02-11.63 vs Males between 16 and 64 years: RR 5.00, 95%CI 2.08-12.03) but not for females. Interestingly, colder temperatures were related to respiratory deaths in the earliest time period (1992-2000), however, no strong cold effect was observed for later periods (2000-2017). In contrast, no heat effect was observed during the study period and across other groups.Conclusions: The higher risk for cold-related respiratory mortality observed in this study could be due to greater inter-annual variability in winter temperatures which needs further exploration after adjusting for potential physical and socio-demographic attributes. The study provides useful evidence for policymakers to improve local warning systems, adaptation, and intervention strategies to reduce the impact of cold temperatures. [ABSTRACT FROM AUTHOR]

We present our optical photometric observations of the 2022 eruption of the recurrent nova U Scorpii (U Sco) using 49152 data points over 70 d following the optical peak. We have also analyzed its soft X-ray (0.3–1 keV) light curve by the Neil Gehrels Swift Observatory. During the 2022 eruption, the optical plateau stage started 13.8–15.0 d and ended 23.8–25.0 d after the optical peak. The soft X-ray stage started 14.6–15.3 d and ended 38.7–39.5 d after the optical peak. Both stages started later and had shorter durations, and the soft X-ray light curve peaked earlier and was less luminous compared to those during the U Sco 2010 eruption. These points suggest that there were differences in the envelope mass between the different cycles of the nova eruption. Furthermore, we have analyzed the optical eclipses during the 2022 eruption. The primary eclipse was first observed 10.4–11.6 d after the optical peak, earlier than the beginning of the optical plateau stage. This sequence of events can be explained by the receding ejecta photosphere associated with the expanding nova ejecta. We have determined the ingress and egress phases of the primary eclipses and estimated the outer radius of the optical light source centered at the white dwarf (WD). During the optical plateau stage, the source radius remained ∼1.2 times larger than the Roche volume radius of the primary WD, being close to the L1 point. When the optical plateau stage ended, the source radius drastically shrank to the tidal truncation radius within a few orbital periods. This previously unresolved phenomenon can be interpreted as a structural change in U Sco where the temporarily expanded accretion disk due to the nova wind returned to a steady state. [ABSTRACT FROM AUTHOR]

This document is an erratum for an article titled "Optical and soft X-ray light-curve analysis during the 2022 eruption of U Scorpii: Structural changes in the accretion disk." The erratum corrects an error in the email address that was mistakenly typed during the production process. The PDF and HTML versions of the original article have been updated with the correct email address. The article is authored by a diverse group of individuals from various institutions. [Extracted from the article]

Seagrass meadow characteristics, including distribution, shape, size and within-meadow architectural features, may be influenced by various physical factors, including hydrodynamic forces. However, such influences have hardly been assessed for meadows of the ecologically important and endemic Mediterranean seagrass Posidonia oceanica. The distribution of P. oceanica meadows at five sites in the Maltese Islands was mapped to a depth of c. 15 m using a combination of aerial photography and SCUBA diving surveys. Estimates of wind-generated wave energy and energy attenuated by depth were computed using the hydrodynamic model WEMo (Wave Exposure Model). Metrics for P. oceanica landscape features were calculated using FRAGSTATS for replicate 2500 m2 subsamples taken from the seagrass habitat maps in order to explore the influence of wave dynamics at the landscape scale. Data on within-meadow architectural attributes were collected from five sites and analysed for relationships with wave energy. The results indicate that landscape and architectural features of P. oceanica meadows located within the 6-11 m depth range are significantly influenced by wave climate. Posidonia oceanica meadows tend to be patchier and have low overall cover, more complex patch shapes and reduced within-patch architectural complexity along a wave exposure gradient from low to high energy. The findings from the present study provide new insight into the influence of hydrodynamic factors on the natural dynamism of P. oceanica meadow landscape and architecture, which has implications for the conservation and management of the habitat. [ABSTRACT FROM AUTHOR]

We present optical photometry of six intermediate polars that exhibit transitions to a low-flux state. For four of these systems, DW Cnc, V515 And, V1223 Sgr, and RX J2133.7+5107, we are able to perform timing analysis in and out of the low states. We find that, for DW Cnc and V515 And, the dominant periodicities in the light curves change as the flux decreases, indicating a change in the sources’ accretion properties as they transition to the low state. For V1223 Sgr, we find that the variability is almost completely quenched at the lowest flux, but we do not find evidence for a changing accretion geometry. For RX J2133.7+5107, the temporal properties do not change in the low state, but we do see a period of enhanced accretion that is coincident with increased variability on the beat frequency, which we do not associate with a change in the accretion mechanisms in the system. [ABSTRACT FROM AUTHOR]

The urban environment is characterised by many pressures caused by population growth, transport (and its related emissions), and the damage to green areas. Yet, there is a variety of ecosystem services available in urban areas, which may be deployed to ameliorate the current problems and foster their sustainability. This paper reviews the role of ecosystem services as tools for sustainability, based on an urban setting. It also describes a series of multi-country case studies, where an assessment of their functions using a set of benefits valuation approaches such as health benefits, economic benefits, social benefits and benefits to climate resilience, are provided, along with an appraisal of their role in up-keeping the overall quality of the urban environment in the studied areas. Policy recommendations aimed at enhancing the role of ecosystem services, and fostering sustainability in the sampled sites -and beyond-are provided. [ABSTRACT FROM AUTHOR]