Hot-summer Mediterranean Climate Research Articles

The impacts of urban canyons morphology on daylight availability and energy consumption of buildings in a hot-summer Mediterranean climate

Proper sunlight access has a positive impact on the physical and mental health of citizens, as well as on reducing energy consumption. This capacity may be limited by inappropriate urban morphology, and urban canyons and buildings are deprived of proper daylight. The purpose of this research is to study the current solar potential on the surface of the canyons and buildings and the effect of urban morphology parameters on the amount of each of the main variables of the research in Ilam, Iran. First, solar radiation, daylight illuminance, and air temperature were measured at different points of the studied canyons for three days. After that, the studied area was modeled with Rhino-Grasshopper software, and simulation was done using Ladybug Tools and UMI plugin. The results showed that the amount of daylight available in most canyons is low. Less than 30 % of the canyon’s surfaces benefited from 6 h of direct sunlight during the measurement. The simulation results for the 62 studied buildings showed that the highest amount of daylight is related to buildings with a height of more than 10 m. 56 % of the buildings had an annual solar radiation of less than 500 mw/m2. The roofs of the buildings received the most radiation, accounting for 72 % of the total radiation. By examining the parameters of urban morphology, it was found that the most influential parameter on the amount of solar radiation was the floor area, and the height of the buildings had the most influence on energy consumption.

Investigation of the effectiveness of top-down natural ventilation of a poultry building in a hot-summer mediterranean climate

In this study, computational fluid dynamics (CFD) was used to examine the efficiency of ventilation and airflow patterns in a multi-level layer hen house. The utilization of windcatchers as a natural ventilation system was the main area of focus. By comparing CFD simulations with experimental data using ANSYS Fluent, the results were validated. The findings showed good agreement in airflow velocity within the windcatchers and throughout the entire building between the CFD calculations and the experimental tests, resulting in uniform airflow distribution and the absence of turbulence in the area where the chickens were kept. This setup provided the layer hens with an acceptable level of comfort by maintaining a consistent and steady temperature profile. The windcatcher-based model demonstrated better temperature uniformity than mechanical window ventilation. The study also emphasized the importance of maintaining appropriate humidity levels throughout the building to ensure the comfort and productivity of layer hens. The advantages of the windcatcher-based system in terms of temperature distribution and airflow control were highlighted by comparison with an alternative ventilation model. These results underscore the importance of using natural ventilation systems, such as windcatchers, to create optimal ventilation conditions and provide layer hens with a comfortable and productive environment (resulting in a temperature reduction from 29°C to 19.85°C with a low and uniform air velocity ranging from 0 m/s to 0.7 m/s at cage level). Practical application An effective and eco-friendly approach to enhance animal health and productivity in poultry farms is to install a natural ventilation system with wind collectors. This setup creates optimal conditions for the animals by improving air quality, regulating temperature, and fine-tuning ventilation. Additionally, it promotes overall sustainability in poultry facilities by lowering energy costs and advocating for environmentally friendly management, aligning agricultural practices with stringent environmental standards.

Example-based dynamic façade design using the facade daylighting performance improvement (FDPI) indicator

It remains challenging to conduct an efficient dynamic façade design. In this article authors try to address this issue introducing the façade daylighting performance improvement (FDPI) indicator aimed to evaluate the performance of a dynamic (adaptive) façade from its daylighting performance point of view. To illustrate the FDPI application the authors introduced the preliminary dynamic façade concept for an office building located in Tel Aviv (Hot-summer Mediterranean Climate Csa) with further shape modification based on the daylighting performance analysis compared to the three alternatives representative of different typologies of dynamic facades. Al Bahr, One Ocean and The University of Southern Denmark façade systems were simulated under the same weather and building conditions of the preliminary dynamic façade concept and were considered as a benchmark for the study. The final dynamic façade concept elaborated by the authors in the preliminary comparative workflow showed noticeable daylight performance improvement with respect to the case studies comparative scenarios. The FDPI metric allowed to estimate a daylighting performance improvement of 43% of the final dynamic façade concept over the case study dynamic façade that showed the best performance in the daylighting simulations.

The Adaptive Value of Chromosomal Inversions and Climatic Change-Studies on the Natural Populations of Drosophila subobscura from the Balkans.

The adaptive value of the Drosophila subobscura chromosomal inversion polymorphism with regard to environmental effects is well-known. However, the specific details of the inversion adaptations to the global warming scenario deserve to be analyzed. Toward this aim, polymorphism and karyotypes were studied in 574 individuals from Petnica (Serbia) in annual samples taken in June for the period 2019-2022. Comparing the results of Petnica (Cfa: humid subtropical climate) with those from Avala (Serbia: Cfb, temperate oceanic climate) and Font Groga (Barcelona, Spain; Csa: hot-summer Mediterranean climate), significant differences were observed for their chromosomal polymorphism. In Petnica, inversions from U and E chromosomes mainly reacted significantly with regard to temperature, humidity, and rainfall. Moreover, the inversion polymorphism from Petnica (2019-2022) was compared with that from 1995. In this period, a significant increase in mean and maximum temperature was observed. However, to properly explain the observed variations of inversions over time, it was necessary to carefully analyze annual seasonal changes and particular heat wave episodes. Interestingly, yearly fluctuations of U chromosome 'warm'-adapted inversions corresponded with opposite changes in 'non-thermal' inversions. Perhaps these types of inversions were not correctly defined with regard to thermal adaptation, or these fluctuations were also due to adaptations to other physical and/or biological variables. Finally, a joint study of chromosomal inversion polymorphism from many Balkan populations of D. subobscura indicated that different climatic regions presented distinct composition, including thermal-adapted inversions.

Outdoor Thermal Comfort Integrated with Energy Consumption for Urban Block Design Optimization: A Study of the Hot-Summer Mediterranean City of Irbid, Jordan

With an increasing awareness of urban health and well-being, this study highlights the growing importance of considering environmental quality in urban design beyond mere energy performance. This study integrates outdoor and indoor quality by investigating the effect of design parameters at an urban block scale (building form restricted to width and length as rectangular and square, building orientation, block orientation, building combination, building height, facade length, built-up percentage, setbacks, and canyon aspect ratio) on outdoor thermal comfort and energy use intensity. In addition, it explains the different correlations between outdoor thermal comfort and energy use intensity in different urban block designs in a hot-summer Mediterranean climate in Jordan. The study adopts a performance-driven approach using simulation tools of Ladybug, Honeybee, Dragonfly, and Eddy3d plugins across the grasshopper interface and evaluates 59 different urban block designs with nine different orientations (0°, 1°, 45°, 85°, 87°, 90°, 355°, 358°, and 359°). The results show that there is a positive correlation between the canyon aspect ratio and the environmental performance of the urban block designs. North–south street canyons are more effective at enhancing microclimates. Negatively increasing the street aspect ratio by more than four affected outdoor thermal comfort by increasing longwave radiation. Further results suggest a positive correlation between the compactness of urban blocks and their environmental performance, with north–south street canyons found to be more effective in enhancing microclimates. The study emphasizes the need to understand the distribution of open spaces formed by buildings and to strike a balance between day and night, as well as summer and winter conditions in outdoor spaces.

The significance of shade provision in reducing street-level summer heat stress in a hot Mediterranean climate

The rise in air temperature in urban areas has been attracting the attention of urban climate researchers for years now, focusing on the intensity of the so-called Urban Heat Island (UHI) phenomenon. Recently, though, it has been rightly questioned whether the concept of UHI intensity is helpful in assessing mitigation of urban heat stress, especially since the concept does not reflect the spatial and temporal microscale climatic differences between adjacent intra-urban locations and the much lower magnitude of the UHI effect during daytime. Moreover, while UHI research is focused on near-surface air temperature levels, the existing evidence makes it clear that air temperature does not fully describe the intensity of street-level daytime heat stress during the hot season.This study attempted to evaluate the correlation between exposure to shortwave radiation and significant increases in heat stress under summer conditions through extensive monitoring. Using a mobile measurement setup we monitored summer daytime outdoor conditions in 148 unique locations in Tel Aviv-Yafo, a coastal city with a hot-summer Mediterranean climate. Analysis of the resulting dataset showed the decisive effect of solar exposure on significantly increased heat stress according to three common thermal comfort indices. A much weaker correlation was observed between comfort levels and air temperature, relative humidity, and wind speed levels. These findings support the conclusion that under summer daytime conditions in similarly hot climates the provision of shade has a far stronger positive effect on reducing heat stress than, for example, feasible reductions in air temperatures or increases in wind speed.

Impact of nano‐enhanced phase change material on thermal performance of building envelope and energy consumption

Using phase change material (PCM) in the building envelope can provide energy saving advantages by shaving peak heating and cooling loads. However, the poor thermal conductivity of PCMs limits their application and potential benefits because of inadequate heat storage/release rates. Increasing effective thermal conductivity by adding metal nanoparticles with high thermal conductivity to PCM (NPCM) could be a promising method to accelerate the phase change process, thereby exploiting latent heat more effectively. The potential impact of the utilization of NPCM technology has not yet been adequately explored for building external walls. This study aimed to reveal whether the dispersal of highly conductive nanoparticles in PCM in external building walls helps conserve energy or not. PCM enriched with aluminium oxide nanoparticles (Al2O3) with a content of 1, 2, and 3 vol% was used. The outputs showed that the nanoparticle addition decreased the energy-saving performance of PCM since the reduction in the thermal resistance and latent heat capacity caused by the nanoparticles loading was more profound than the enhancement provided by the improvement of latent heat exploitation caused by the increased thermal conductivity. For example, heating energy saving was reduced by 0.6% when a 3-cm PCM with 1 vol% Al2O3 was used instead of a pure PCM. The negative impact increased to 1.7% by increasing the nanoparticle concentration to 3 vol%. Thus, augmenting the thermal conductivity for higher latent heat activation by adding nanoparticles was not beneficial for building wall applications in a hot-summer Mediterranean climate. Highlights Effect of nanoparticle-enhanced PCM on building energy saving. PCM with Al2O3 content of 0, 1, 2, and 3 vol% embedded in external wall. Yearly energy saving of 20.7% was achieved with pure PCM in the wall. Adding 3 vol% Al2O3 to PCM reduced heating energy saving by 1.7%. Negative effect on energy saving increased with increasing nanoparticle concentration.

Physiological and Transcriptional Responses to Saline Irrigation of Young 'Tempranillo' Vines Grafted Onto Different Rootstocks.

The use of more salt stress-tolerant vine rootstocks can be a sustainable strategy for adapting traditional grapevine cultivars to future conditions. However, how the new M1 and M4 rootstocks perform against salinity compared to conventional ones, such as the 1103-Paulsen, had not been previously assessed under real field conditions. Therefore, a field trial was carried out in a young ‘Tempranillo’ (Vitis vinifera L.) vineyard grafted onto all three rootstocks under a semi-arid and hot-summer Mediterranean climate. The vines were irrigated with two kinds of water: a non-saline Control with EC of 0.8 dS m–1 and a Saline treatment with 3.5 dS m–1. Then, various physiological parameters were assessed in the scion, and, additionally, gene expression was studied by high throughput sequencing in leaf and berry tissues. Plant water relations evidenced the osmotic effect of water quality, but not that of the rootstock. Accordingly, leaf-level gas exchange rates were also reduced in all three rootstocks, with M1 inducing significantly lower net photosynthesis rates than 1103-Paulsen. Nevertheless, the expression of groups of genes involved in photosynthesis and amino acid metabolism pathways were not significantly and differentially expressed. The irrigation with saline water significantly increased leaf chloride contents in the scion onto the M-rootstocks, but not onto the 1103P. The limitation for leaf Cl– and Na+ accumulation on the scion was conferred by rootstock. Few processes were differentially regulated in the scion in response to the saline treatment, mainly, in the groups of genes involved in the flavonoids and phenylpropanoids metabolic pathways. However, these transcriptomic effects were not fully reflected in grape phenolic ripeness, with M4 being the only one that did not cause reductions in these compounds in response to salinity, and 1103-Paulsen having the highest overall concentrations. These results suggest that all three rootstocks confer short-term salinity tolerance to the scion. The lower transcriptomic changes and the lower accumulation of potentially phytotoxic ions in the scion grafted onto 1103-Paulsen compared to M-rootstocks point to the former being able to maintain this physiological response in the longer term. Further agronomic trials should be conducted to confirm these effects on vine physiology and transcriptomics in mature vineyards.

Installation Season May Significantly Impact Time Required for Subterranean Termites to Find and Feed on In-Ground Baits.

Simple SummaryInsecticide baits for use against subterranean termites have been shown to be highly effective, but the time required for termites to find and feed on baits may be a barrier to adoption in some areas. One explanation for this “time-to-attack” problem is that termite foraging near the soil surface may be limited during inhospitable periods. In California, characterized by a hot-summer Mediterranean climate, western subterranean termites have mostly been observed near the surface during the wet season, suggesting that baits installed in summer may sit uninvestigated for many months. To test this hypothesis, we established research plots in areas of known termite incidence, installing baits on four different dates over a one-year period and then recording termite activity every 60 days for two years. As expected, most foraging in these stations was observed in winter and spring. Time-to-attack for stations installed at the beginning of winter was significantly less than for stations installed at the beginning of summer (194 d vs. 296 d). These findings may help pest control operators in regions with pronounced dry periods to optimize their use of bait station systems by targeting specific installation seasons.Rhinotermitid termites, serious pests of wooden structures throughout the world, are commonly controlled with chitin synthesis inhibitor bait systems. Seasonal termite foraging patterns in some regions may prolong bait interception time, however, significantly decreasing colony elimination speed. We hypothesized that installing baits immediately prior to the season of highest foraging activity will minimize interception time when baiting for Reticulitermes spp. in California, a region characterized by a hot-summer Mediterranean climate. To test this theory, we installed three different bait systems on four dates corresponding to the major seasons (spring, summer, autumn, winter) at five field locations known to harbor the target species. We then recorded initial termite discovery events every 60 days for two years, considering effects of installation season, bait system, site, and distance from previously observed termite incidence on bait interception time. Observed foraging activity in bait stations was highest during late winter and spring. Baits installed during winter exhibited interception times more than 100 days shorter than those of baits installed during summer. From these findings, we conclude that colony elimination speed and perceived CSI bait utility may be increased in Mediterranean climate regions when baits are installed immediately prior to the wet season.

Enhanced pilot bioremediation of oily sludge from petroleum refinery disposal under hot-summer Mediterranean climate

Large pilot scale bioremediation approaches were implemented for the treatments of oily sludge (OS) characterised by alkaline pH (pH > 9), high concentration of metals (3% dry weight) and high total petroleum hydrocarbons content (TPH) rangingbetween 22,000 and 67,300 mg kg −1 from a Tunisian petroleum refinery. The treatments included bioaugmentation and biostimulation approaches with autochthonous isolated bacterial strains and consortia. Chemical, microbial, and ecotoxicological analyses were performed over a period of 180 days incubation. The bioremediation treatments favoured the development of Proteobacteria , Firmicutes and Bacteroidetes following an ecological succession of specialist bacterial groups, first associated to hydrocarbon degradation (e.g. Marinobacter and Alcanivorax ) that resulted in a greater extent of TPH-degradation (up to 80%), and the selection of metal resistant bacteria including Hyphomonas , Phaeobacter , and Desulfuromusa . The best performances were obtained when bioaugmentation and biostimulation were combined. Over 90% of the TPH initial concentration was degraded over 180 days, which was accompanied with a 3-fold reduction of ecotoxicity. Our study demonstrates the efficacy of large pilot scale bioremediation of highly contaminated oily sludge, providing the evidence that the management of autochthonous microbial communities is of paramount importance for the success of the bioremediation process. • Effective oil sludge bioremediation by managing bacterial community. • Optimal treatment combining bioaugmentation and biostimulation. • Bacterial community plasticity evidenced through ecological succession.

Evaluation of NASA POWER Reanalysis Products to Estimate Daily Weather Variables in a Hot Summer Mediterranean Climate

This study aims to evaluate NASA POWER reanalysis products for daily surface maximum (Tmax) and minimum (Tmin) temperatures, solar radiation (Rs), relative humidity (RH) and wind speed (Ws) when compared with observed data from 14 distributed weather stations across Alentejo Region, Southern Portugal, with a hot summer Mediterranean climate. Results showed that there is good agreement between NASA POWER reanalysis and observed data for all parameters, except for wind speed, with coefficient of determination (R2) higher than 0.82, with normalized root mean square error (NRMSE) varying, from 8 to 20%, and a normalized mean bias error (NMBE) ranging from –9 to 26%, for those variables. Based on these results, and in order to improve the accuracy of the NASA POWER dataset, two bias corrections were performed to all weather variables: one for the Alentejo Region as a whole; another, for each location individually. Results improved significantly, especially when a local bias correction is performed, with Tmax and Tmin presenting an improvement of the mean NRMSE of 6.6 °C (from 8.0 °C) and 16.1 °C (from 20.5 °C), respectively, while a mean NMBE decreased from 10.65 to 0.2%. Rs results also show a very high goodness of fit with a mean NRMSE of 11.2% and mean NMBE equal to 0.1%. Additionally, bias corrected RH data performed acceptably with an NRMSE lower than 12.1% and an NMBE below 2.1%. However, even when a bias correction is performed, Ws lacks the performance showed by the remaining weather variables, with an NRMSE never lower than 19.6%. Results show that NASA POWER can be useful for the generation of weather data sets where ground weather stations data is of missing or unavailable.

Estimation of Reference Evapotranspiration during the Irrigation Season Using Nine Temperature-Based Methods in a Hot-Summer Mediterranean Climate

The FAO-56 Penman–Monteith (PM) equation is regarded as the most accurate equation to estimate reference evapotranspiration (ETo). However, it requires a broad range of data that may not be available or of reasonable quality. In this study, nine temperature-based methods were assessed for ETo estimation during the irrigation at fourteen locations distributed through a hot-summer Mediterranean climate region of Alentejo, Southern Portugal. Additionally, for each location, the Hargreaves–Samani radiation adjustment coefficient (kRs) was calibrated and validated to evaluate the appropriateness of using the standard value, creating a locally adjusted Hargreaves–Samani (HS) equation. The accuracy of each method was evaluated by statistically comparing their results with those obtained by PM. Results show that the calibration of the kRs, a locally adjusted HS method can be used to estimate daily ETo acceptably well, with RMSE lower than 0.88 mm day−1, an estimation error lower than 4% and a R2 higher than 0.69, proving to be the most accurate model for 8 (out of 14) locations. A modified Hargreaves–Samani method also performed acceptably for 4 locations, with a RMSE of 0.72–0.84 mm day−1, a slope varying from 0.95 to 1.01 and a R2 higher than 0.78. One can conclude that, when weather data is missing, a calibrated HS equation is adequate to estimate ETo during the irrigation season.

A Simple Procedure to Estimate Reference Evapotranspiration during the Irrigation Season in a Hot-Summer Mediterranean Climate

The Food and Agricultural Organization of the United Nations (FAO) Penman–Monteith (PM) method is widely regarded as the most effective reference evapotranspiration (ETo) estimator; however, it requires a wide range of data that may be scarce in some rural regions. When feasible relative humidity, solar radiation and wind speed data are unavailable, a temperature-based method may be useful to estimate ETo and provide suitable data to support irrigation management. This study has evaluated the accuracy of two ETo estimations methods: (1) a locally and monthly adjusted Hargreaves–Samani (HS) equation; (2) a simple procedure that only uses maximum temperature and a temperature adjustment coefficient (MaxTET). Results show that, if a monthly adjusted radiation adjustment coefficient (kRs) is calibrated for each site, acceptable ETo estimations (RMSE and R2 equal to 0.79 for the entire region) can be achieved. Results also show that a procedure to estimate ETo based only on maximum temperature performs acceptably, when compared with ETo estimation using PM equation (RMSE = 0.83 mm day−1 and R2 = 0.77 for Alentejo). When comparing these results with the ones attained when adopting a monthly adjusted HS method, the MaxTET procedure proves to be an accurate ETo estimator. Results also show that both methods can be used to estimate ETo when weather data are scarce.

Determination of heavy metals in the territory of contaminated areas of Greece and their restoration through hyperaccumulators

Phytoremediation is an effective technique for the processing of contaminated soil and for sequestering environmental contaminants such as heavy metals. This kind of pollution is ubiquitous in mines and similar excavation sites. This mini-review aims to provide an overview of the alternative forms of restoring contaminated soils (phytoremediation) highlighting the areas of Kozani (Agios Dimitrios) and Chalkidiki (Stratoni) in Greece characterized by exorbitant metallurgical activities. Firstly, a literature search in databases such as ScienceDirect, SciFinder, PubMed, Google Scholar, and Scopus was conducted, using the following keywords to identify relevant articles: "utilization", "plants", "phytoremediation", "sustainability", "environment", and "restoration". Two case studies have subsequently been chosen in Northern Greece, one characterized by metal mining (Pb, Zn, Ag) and hot summer Mediterranean climate and another one involving lignite mining and concomitant Cr, Zn, Cu, and Ni pollution under subtropical climate. Based on the literature search some possible, non-invasive plant species were proposed, focusing on the most efficient hyperaccumulators.

The Importance of High Resolution Digital Elevation Models for Improved Hydrological Simulations of a Mediterranean Forested Catchment

Eco-hydrological models can be used to support effective land management and planning of forest resources. These models require a Digital Elevation Model (DEM), in order to accurately represent the morphological surface and to simulate catchment responses. This is particularly relevant on low altimetry catchments, where a high resolution DEM can result in a more accurate representation of terrain morphology (e.g., slope, flow direction), and therefore a better prediction of hydrological responses. This work intended to use Soil and Water Assessment Tool (SWAT) to assess the influence of DEM resolutions (1 m, 10 m and 30 m) on the accuracy of catchment representations and hydrological responses on a low relief forest catchment with a dry and hot summer Mediterranean climate. The catchment responses were simulated using independent SWAT models built up using three DEMs. These resolutions resulted in marked differences regarding the total number of channels, their length as well as the hierarchy. Model performance was increasingly improved using fine resolutions DEM, revealing a bR2 (0.87, 0.85 and 0.85), NSE (0.84, 0.67 and 0.60) and Pbias (−14.1, −27.0 and −38.7), respectively, for 1 m, 10 m and 30 m resolutions. This translates into a better timing of the flow, improved volume simulation and significantly less underestimation of the flow.

Köppen’s climate classification projections for the Iberian Peninsula

Projections of Köppen-Geiger climate classifications under future climate change for the Iberian Peninsula are investigated using a 7-ensemble mean of regional climate models obtained from EURO-CORDEX. Maps with predicted future scenarios for temperature, precipitation and Köppen-Geiger classification are analyzed for RCP4.5 and RCP8.5 in Iberia. Widespread statistically significant shifts in temperature, precipitation and climate regimes are projected in the 2041-2070 period, with greater shifts occurring under RCP8.5. An overall increase in temperature and a decrease in precipitation in the south-southeast is predicted. Of the two climate types, dry (B) and temperate (C), the dominant one was C in 86% of Iberia for 1961-1990, predicted to decrease by 8.0% by 2041-2070 under RCP4.5 (9.5% under RCP8.5). The hot-summer Mediterranean climate (CSa) will progressively replace CSb (warm-summer climate) in the northwestern half of Iberia until 2070. This shift, depicted by the SSIM index, is particularly noticeable in Portugal, with the projected establishment of the CSa climate by 2041-2070. The predicted retreat of humid subtropical (Cfa) and temperate oceanic (Cfb) areas in the northeast towards the Pyrenees region is noteworthy, as is the increase of desert (BW) and semi-desert (BS) climates (7.8 and 9%) in the southeast (between Granada and Valencia). Climate types BSh and BWh (hot semi-desert and hot desert, respectively), non-existent in the 1961-1990 period, are projected to represent 2.8% of the territory in 2041-2070 under RCP4.5 (5% under RCP8.5). The statistically significant projected changes hint at the disappearance of some vegetation species in certain regions of Iberia, with an expected increase in steppe, bush, grassland and wasteland vegetation cover, typical of dry climates in the southeast.

The degree of adaptive thermal comfort in office workers in a hot-summer Mediterranean climate

This study aims to investigate occupants’ perception of feeling comfortable over different seasons in offices located in Amman, Jordan, to determine the comfort temperature zones, and to compare the results developed from this study with other adaptive models and standards. It is based on longitudinal field surveys, which were conducted in three office buildings, two mixed mode buildings and a free running building, during four seasons: April 2016 (spring), July/August 2016 (summer), October 2016 (autumn) and January/February 2017 (winter). A total of 119 occupants participated in the thermal comfort surveys and completed 659 questionnaires. The free running building experienced a variation in operative temperature during the four seasons, while median temperatures in the mixed-mode buildings stayed almost the same during all seasons. Occupants felt comfortable in a broad range of thermal sensations from ‘cool’ to ‘warm’. Thermal comfort was expressed by a high proportion of the occupants. Occupants changed their clothing insulation with season, whereby compared to winter some occupants showed a changed clothing insulation already in the spring survey and others only in the summer and autumn survey. A Loess analysis between the temperatures at which the occupants felt comfortable and the running mean outdoor temperature indicated independency between the two variables in case of the mixed-mode buildings at running mean outdoor temperatures below 22 °C, but a trend towards decreasing comfort temperature above 22 °C. The comfort temperature in both mixed mode buildings was around 23.5 °C. In the free running building, a monotonically increasing linear relation between the two variables was found at running mean outdoor temperatures below appr. 24 °C, but a constant comfort temperature of about 26 °C above this value. Compared to the adaptive comfort models in ASHRAE Standard 55 and EN 15251 the gradient in the adaptive comfort equation resulting from the free running building in Amman was higher. Although the occupants adjusted their clothing insulation level, the gradient in the comfort equation was close to zero in the mixed mode buildings.

Multiple factors influence the consistency of cropland datasets in Africa

Accurate geo-information of cropland is critical for food security strategy development and grain production management, especially in Africa continent where most countries are food-insecure. Over the past decades, a series of African cropland maps have been derived from remotely-sensed data, existing comparison studies have shown that inconsistencies with statistics and discrepancies among these products are considerable. Yet, there is a knowledge gap about the factors that influence their consistency. The aim of this study is thus to estimate the consistency of five widely-used cropland datasets (MODIS Collection 5, GlobCover 2009, GlobeLand30, CCI-LC 2010, and Unified Cropland Layer) in Africa, and to explore the effects of several limiting factors (landscape fragmentation, climate and agricultural management) on spatial consistency. The results show that total cropland area for Africa derived from GlobeLand30 has the best fitness with FAO statistics, followed by MODIS Collection 5. GlobCover 2009, CCI-LC 2010, and Unified Cropland Layer have poor performances as indicated by larger deviations from statistics. In terms of spatial consistency, disagreement is about 37.9 % at continental scale, and the disparate proportion even exceeds 50 % in approximately 1/3 of the countries at national scale. We further found that there is a strong and significant correlation between spatial agreement and cropland fragmentation, suggesting that regions with higher landscape fragmentation generally have larger disparities. It is also noticed that places with better consistency are mainly distributed in regions with favorable natural environments and sufficient agricultural management such as well-developed irrigated technology. Proportions of complete agreement are thus located in favorable climate zones including Hot-summer Mediterranean climate (Csa), Subtropical highland climate (Cwb), and Temperate Mediterranean climate (Csb). The level of complete agreement keeps rising as the proportion of irrigated cropland increases. Spatial agreement among these datasets has the most significant relationship with cropland fragmentation, and a relatively small association with irrigation area, followed by climate conditions. These results can provide some insights into understanding how different factors influence the consistency of cropland datasets, and making an appropriate selection when using these datasets in different regions. We suggest that future cropland mapping activities should put more effort in those regions with significant disagreement in Sub-Saharan Africa.

Shade maps for prioritizing municipal microclimatic action in hot climates: Learning from Tel Aviv-Yafo

This article presents a methodology for evaluating microclimatic summer conditions across an entire city, focusing on the provision of outdoor shade as a primary comfort indicator. Based on high-resolution 2.5D and 3D mapping of buildings, ground surfaces, and tree canopies in Tel Aviv-Yafo, a city of hot-summer Mediterranean climate, we employed a detailed calculation of solar exposure of streets and open spaces (public and private) using commonly available GIS algorithms. The raw results of these calculations were used for calculating summer Shade Index values for every street segment and neighbourhood of the city, which were then plotted to a comprehensive 'shade maps' reflecting the city's spatial hierarchy of shade. The shade maps, combined with analysis of tree canopy cover on similar scales, enabled to relate building and tree morphologies to outdoor shade conditions. For prioritizing intervention of local planning authorities in improving poor shade conditions or conserving highly-shaded locations, we related the climatic analysis to space-syntax classification of streets according to their potential to attract pedestrian movement, and produced a city-wide map that highlighted streets that have high pedestrian movement potential while requiring high levels of shade intensification or conservation.

Building and environmental factors that influence bacterial and fungal loading on air conditioning cooling coils.

We investigated bacterial and fungal concentrations on cooling coils of commercial AC units and quantified associations between microbial loads and AC unit or building operational parameters. A field campaign was conducted to sample 25 AC units in the humid, subtropical climate of Southern CT, USA and 15 AC units in the hot-summer Mediterranean climate of Sacramento, CA, USA. Median concentrations (with interquartile range) of bacteria and fungi on the cooling coils were 1.2×107 (5.1×106 -3.9×107 ) cells/m2 and 7.6×105 (5.6×104 -4.4×106 ) spore equivalents (SE)/m2 , respectively. Concentrations varied among units with median unit concentrations ranging three orders of magnitude for bacteria and seven orders of magnitude for fungi. Controlled comparisons and multivariable regressions indicate that dominant factors associated with AC coil loading include the nominal efficiency of upstream filters (P=.008 for bacteria and P<.001 for fungi) and coil moisture, which was reflected in fungal loading differences between top and bottom halves of the AC coils in Southern CT (P=.05) and the dew points of the two climates considered (P=.04). Environmental and building characteristics explained 42% (P<.001) of bacterial concentration variability and 66% (P<.001) of fungal concentration variability among samples.