Hot Wind Research Articles

Effect of hot wind on insects in longan (Dimocarpus longan Lour.) orchard during off-season production in the Chao Phraya Delta

Effect of hot wind on insects in longan (<i>Dimocarpus longan</i> Lour.) orchard during off-season production in the Chao Phraya Delta

Study on the Influence of Mounting Dimensions of PV Array on Module Temperature in Open-Joint Photovoltaic Ventilated Double-Skin Façades

In building integrated photovoltaics (PV), it is important to solve the heat dissipation problem of PV modules. In this paper, the computational fluid dynamics (CFD) method is used to simulate the flow field around the open-joint photovoltaic ventilated double-skin façades (OJ-PV-DSF) to study the influence of the mounting dimensions (MD) of a PV array on the module temperature. The typical summer afternoon meteorological parameters, such as the total radiation (715.4 W/m2), the outdoor temperature (33.1 °C), and the wind speed (2.0 m/s), etc., are taken as input parameters. With the DO (discrete ordinates) model and the RNG (renormalization-group) k − ε model, a steady state calculation is carried out to simulate the flow of air in and around the cavity under the coupling of hot pressure and wind pressure, thereby obtaining the temperature distribution of the PV array and the wall. In addition, the simulation results are compared with the onsite experimental data and thermal imaging to verify the accuracy of the CFD model. Then three MD of the open joints are discussed. The results show that when the a value (represents the distance between PV modules and wall) changes from 0.05 to 0.15, the temperature drop of the PV module is the most obvious, reaching 2.0 K. When the b value (representing the distance between two adjacent PV modules in the vertical direction) changes from 0 to 0.1, the temperature drop of the PV module is most obvious, reaching 1 K. When the c value (represents the distance between two adjacent PV modules in the horizontal direction) changes from 0 to 0.1, the temperature of the PV module is lowered by 0.8 K. Thus, a = 0.1–0.15, b = 0.1 and c = 0.1 are recommended for engineering applications to effectively reduce the module temperature.

Blow-away in the Extreme Low-mass Starburst Galaxy Pox 186

Abstract Pox 186 is an exceptionally small dwarf starburst galaxy hosting a stellar mass of ∼105 M ⊙. Undetected in H i (M &lt; 106 M ⊙) from deep 21 cm observations and with an [O iii]/[O ii] (5007/3727) ratio of 18.3 ± 0.11, Pox 186 is a promising candidate Lyman continuum emitter. It may be a possible analog of low-mass reionization-era galaxies. We present a spatially resolved kinematic study of Pox 186 and identify two distinct ionized gas components: a broad one with σ &gt; 400 km s−1 and a narrow one with σ &lt; 30 km s−1. We find strikingly different morphologies between the two components and direct evidence of outflows as seen in the high-velocity gas. Possible physical mechanisms driving the creation of high-velocity gas seen in [O iii] are discussed, from outflow geometry to turbulent mixing between a hot (106 K) star-cluster wind and cooler (104 K) gas clouds. We find a modest mass-outflow rate of 0.022 M ⊙ yr−1 with a small mass-loading factor of 0.5, consistent with other low-mass galaxies. Finally, we compare the mass-loading factor of Pox 186 with extrapolations from numerical simulations and discuss possible reasons for the apparent discrepancy between them.

Winter AOD trend changes over the Eastern Mediterranean and Middle East region

AbstractThe present study documents the winter aerosol optical depth (AOD) trends over the Eastern Mediterranean and Middle East (EMME) region using MERRA‐2 and moderate‐resolution imaging spectroradiometer (MODIS) collection 6.1 data. A significant upward AOD trend was identified during the years 2000–2010, whereas the AOD followed a significant downward trend during the years 2010–2017. Our analysis indicates that aeolian dust is the main contributor to AOD changes. The winter AOD changes are related to meteorological factors over the EMME region. During the early period (2000–2010), a significant decrease in sea level pressure induced dry and hot southeasterly winds blowing from the desert regions in the Middle East toward the EMME, which increased the temperature and reduced the relative humidity, thus enhancing evaporation and promoting soil drying. In contrast, during the late period (2010–2017), a significant increase in sea level pressure, accompanied by an increase in the North Atlantic Oscillation (NAO) index, induced northwesterly winds from higher latitudes, which decreased the temperature and increased the relative humidity, reducing dust mobilization in the EMME, in particular, in Iraq and Egypt. This shows to what extent AOD trends in the EMME region are controlled by changing meteorological weather conditions.

The characteristic momentum of radiatively cooling energy-driven galactic winds

ABSTRACT Energy injection by supernovae may drive hot supersonic galactic winds in rapidly star-forming galaxies, driving metal-enriched gas into the circumgalactic medium and potentially accelerating cool gas. If sufficiently mass-loaded, such flows become radiative within the wind-driving region, reducing the overall mass outflow rate from the host galaxy. We show that this sets a maximum on the total outflow momentum for hot energy-driven winds. For a spherical wind of Solar metallicity driven by continuous star formation, $\dot{p}_\mathrm{max} \simeq 1.9\times 10^4\ M_\odot \ \mathrm{yr}^{-1}\ \mathrm{km\ s}^{-1}(\alpha /0.9)^{0.86}\left[R_\star /(300\ \mathrm{pc})\right]^{0.14}[\dot{M}_\star /(20\ M_\odot \ \mathrm{yr}^{-1})]^{0.86},$ where α is the fraction of supernova energy that thermalizes the wind, and $\dot{M}_\star$ and R⋆ are the star formation rate and radius of the wind-driving region. This maximum momentum for hot winds can also apply to cool, ionized outflows that are typically observed in starburst galaxies, if the hot wind undergoes bulk radiative cooling or if the hot wind transfers mass and momentum to cool clouds within the flow. We show that requiring the hot wind to undergo single-phase cooling on large scales sets a minimum on the total outflow momentum rate. These maximum and minimum outflow momenta have similar values, setting a characteristic momentum rate of hot galactic winds that can become radiative on large scales. We find that most observations of photoionized outflow wind momentum fall below the theoretical maximum and thus may be signatures of cooling hot flows. On the other hand, many systems fall below the minimum momentum required for bulk cooling, indicating that perhaps the cool material observed has instead been entrained in or mixed with the hot flow.

Climate shifts vs. edaphic humidity and the difficulty of palaeoreconstructions – a malacological study on stable isotopes in Quaternary dune sequences of Fuerteventura

ABSTRACTDune palaeosurface sequences on the Eastern Canary Islands were investigated for stable isotope records in gastropod shells of the genus Theba. Due to the ecology of the taxon and the special oceanic insularity of the study site, we assume that δ18Oshell signals in our case mainly reflect shifts in δ18O signals of sea surface water. We found that a rapid decrease in δ18Oshell signals is associated with significant changes in gastropod associations. We suggest that these faunal changes were caused by strong (hot) winds at the end of glacial phases, that were described previously by Moreno et al. In addition, we assume that rapid declines in δ18Oshell signals due to marine transgressions were followed by geomorphologically stable phases, dominated by dust enrichment. Such palaeosurfaces correlate with maxima of gastropod biodiversity and with more negative δ13Cshell signals indicating a higher proportion of C3 plants. Based on our results, we also assume that these silty palaeosurfaces were associated with increased soil moisture conditions due to a higher water storage capacity of the finer substrate, independent of climatic moisture conditions.

El cambio climático en los andes y su impacto en la agricultura: una revisión sistemática

In recent years, agriculture in the Andes has shown greater sensitivity to climate change, favoring processes of soil erosion, retreat of glaciers, loss of vegetation cover, increased intensity of rainfall and alteration in the dynamics of crops in the region such as: potato, quinoa, corn, among others. This motivated many authors to develop regional model simulations to estimate the vulnerability index of these agricultural systems to these climatic events, allowing them to provide a more reliable climatological data in the presence of hot and dry winds. In this review article, the main contributions provided by various researchers regarding the impact of climate change on Andean agriculture are detailed. According to the collected information, it is concluded that climate change in the Andes will cause countries such as Brazil, Bolivia, Ecuador, Venezuela, Guyana and Colombia, to increase their local temperature, potential for evapotranspiration and water scarcity, causing the loss of important crops such as rice. In contrast, countries such as Peru, Argentina, Chile, Bolivia and Uruguay will register lower temperatures that will affect their production and yield in crops such as quinoa, potatoes, tarwi, among others.

Unravelling the physics of multiphase AGN winds through emission line tracers

ABSTRACT Observations of emission lines in active galactic nuclei (AGNs) often find fast (∼1000 km s−1) outflows extending to kiloparsec scales, seen in ionized, neutral atomic and molecular gas. In this work we present radiative transfer calculations of emission lines in hydrodynamic simulations of AGN outflows driven by a hot wind bubble, including non-equilibrium chemistry, to explore how these lines trace the physical properties of the multiphase outflow. We find that the hot bubble compresses the line-emitting gas, resulting in higher pressures than in the ambient interstellar medium or that would be produced by the AGN radiation pressure. This implies that observed emission line ratios such as [O iv]$_{25 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, [Ne v]$_{14 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, and [N iii]$_{57 \, \rm {\mu m}}$ / [N ii]$_{122 \, \rm {\mu m}}$ constrain the presence of the bubble and hence the outflow driving mechanism. However, the line-emitting gas is under-pressurized compared to the hot bubble itself, and much of the line emission arises from gas that is out of pressure, thermal and/or chemical equilibrium. Our results thus suggest that assuming equilibrium conditions, as commonly done in AGN line emission models, is not justified if a hot wind bubble is present. We also find that ≳50 per cent of the mass outflow rate, momentum flux, and kinetic energy flux of the outflow are traced by lines such as [N ii]$_{122 \, \rm {\mu m}}$ and [Ne iii]$_{15 \, \rm {\mu m}}$ (produced in the 10$^{4} \, \rm {K}$ phase) and [C ii]$_{158 \, \rm {\mu m}}$ (produced in the transition from 10$^{4} \, \rm {K}$ to 100 K).

Air temperature forecasting using artificial neural network for Ararat valley

The air temperature is a critical factor in many societal challenges to protect human health and the environment. Moreover, a vital climatic parameter, the temperature has a direct impact on evaporation, frost, and snow melting. Temperature predictions are based mainly on numerical and statistical models. Sometimes it is a challenge to improve the weather forecast accuracy. The article aims to implement a weather prediction technique based on machine learning methods and approaches to improve the hourly air temperature prediction for up to 24 hours in the Ararat valley (Armenia). Due to intense heat and low relative humidity, the high temperatures and hot winds occur between 120 and 160 days per year in Ararat valley, as one of the aridest regions of Armenia. The approach utilizes the earth observation data received from several meteorological stations and the large satellite analysis-ready datasets at different frequencies and resolutions. The experiments have been conducted with multiple neural networks to forecast air temperatures for 24 hours that happened over the Ararat valley. The suggested model has 87.31% and 75.57% accuracies to predict the temperature for the next 3 and 24 hours, which is sufficient to be used alongside the current state-of-the-art techniques.

Chandra grating spectroscopy of embedded wind shock X-ray emission from O stars shows low plasma temperatures and significant wind absorption

ABSTRACT We present a uniform analysis of six examples of embedded wind shock (EWS) O star X-ray sources observed at high resolution with the Chandra grating spectrometers. By modelling both the hot plasma emission and the continuum absorption of the soft X-rays by the cool, partially ionized bulk of the wind we derive the temperature distribution of the shock-heated plasma and the wind mass-loss rate of each star. We find a similar temperature distribution for each star’s hot wind plasma, consistent with a power-law differential emission measure, $\frac{{\rm d}\log EM}{{\rm d}\log T}$, with a slope a little steeper than −2, up to temperatures of only about 107 K. The wind mass-loss rates, which are derived from the broadband X-ray absorption signatures in the spectra, are consistent with those found from other diagnostics. The most notable conclusion of this study is that wind absorption is a very important effect, especially at longer wavelengths. More than 90 per cent of the X-rays between 18 and 25 Å produced by shocks in the wind of ζ Pup are absorbed, for example. It appears that the empirical trend of X-ray hardness with spectral subtype among O stars is primarily an absorption effect.

Old-Russian Stribog and his Ancient Greek Brother Astray

The essay analyses the name of a pagan God of the Ancient Rus Stribog, who was mentioned in “The Russian Primary Chronicle” and “The Tale of the Igor’s Campaign” and its connection with the ancient Greek mythology. The article suggests that an old-Russian god Stribog is similar to the ancient Greek god Astray, the father of the famous gods of winds, Boreas — the god of cold northern wind, Zephyr — the god of warm western wind, Anemoi — the god of hot southern wind and Eurus — the god of unstable eastern or south-eastern wind, who are often associated with the winds they symbolize in Russian poetry. The similarity of Stribog and Astray lays not only in their origins, but in the common root str-. The article concludes that because god Astray is not only the farther of the gods of the winds, but also the father of Venus and other stars, it is arguable that Stribog is both the grandfather of the winds and the Slavic god of the night sky.

Hot Wind to the Body Can Facilitate Vection Only When Participants Walk Through a Fire Corridor Virtually

Vection has been reported to be enhanced by wind, as long as the wind is a normal temperature and not hot. However, here we report that a hot wind can facilitate vection, as long as it is natural and consistent with the visual stimulus. We created a fire-corridor stimulus that was consistent with a hot wind and a control stimulus composed of cubes, which were irrelevant to a hot wind. We compared the vection strength induced by a fire-corridor (fire condition) visual stimulus with that induced by geometric cubes (no-fire condition) visual stimulus. There were three wind type conditions: a normal temperature wind, hot wind, and no wind. The results showed that a normal temperature wind facilitated vection and that a hot wind (but not a normal wind) highly enhanced vection when a fire-corridor stimulus was presented. These results suggest that vection is highly affected and modulated by high-level cognitive processes.

What We Can Learn from Vernacular House and COVID-19 Infection? A Review of Mbaru Niang, Flores, Indonesia

The COVID-19 pandemic has shown that the current ventilation design, especially in residential buildings, may not provide healthy air exchange. Since current buildings in tropical climate only focused on cooling, its have become sites of rapid COVID-19 transmission. In order to avoid indoor SARS-Cov-2 transmission, some studies recommended an increase in air supply with a higher air exchange rate and to reduce the usage of the air conditioner. Flores has been designated one of the top Indonesian tourism destinations. However, access to transportation is still tricky. Analysis of local materials, culture, and weather can reduce the building cost and preserved local value to become the area's identity. Vernacular housing in Indonesia has adapted well to climatic conditions in different locations by using natural ventilation that ensures thermal comfort. We propose a ventilation design with natural ventilation from Mbaru Niang's traditional house. It was found that raised floor, verandah, and sun shading can reduce the hot temperature from solar radiation and hot wind from the sea breeze. This modern building concept can become a practical, healthy, and environmentally friendly solution for building in Flores, Indonesia. Introduction

A Fast Drying Machine Based On Semiconductor Heat Pump

The new latent heat recovery type semiconductor heat pump ground fast dryer is a kind of integrated semiconductor refrigeration module on the traditional dryer. We simulated the process of the wind being heated by the hot end of the semiconductor refrigeration module under different working conditions through ANSYS software, so as to obtain the best solution for the semiconductor refrigeration module. Using the principles of drying and air condensation, we calculated the influence of the drying rate, drying time, and the condensation effect of the cold end when the air at different hot end inlet wind speeds, ambient temperature and moisture content blows the same amount of moisture on the ground. Through energy-saving analysis, our design saves about 60% energy compared with traditional electric heating style hair dryers. In the case of the same input power, the outlet air temperature of the semiconductor heat pump ground rapid dryer is significantly higher than that of the electric heating hair dryer. Therefore, when the ground is dry with the same amount of moisture, the use of the new semiconductor heat pump ground rapid dryer can significantly shorten drying time, the best drying time shortening rate is as high as 70%.

Violation of the structure of the forest biocenosis under the action of stem pests and methods of controlling their numbers

The study of the forest ecosystem as an integral part of the erosion system is associated with a number of issues. The forest is the most powerful and effective tool in the fight against soil erosion, droughts and hot winds, as well as an environmental stabilising factor in general. Human forestry activities in the fight against the drying of coniferous plantations from an outbreak of mass reproduction and spread to large areas of stem pests under the influence of a complex of ecological and climatic factors, is one of the serious factors disrupting the structure of the forest biocenosis. The search for alternative solutions to the localisation of this problem requires a detailed study of the behaviour of the most common bark beetles of coniferous trees in climatic and environmental conditions that developed during 2011-2020. During the period of active temperatures in 2019, namely from the second decade of April to the third decade of October, work on stationary supervision and laboratory field work was carried out to solve the problem of localisation of stem pests of Polissya and Forest-Steppe pine plantations. Methods of laying out hunting trees and pheromone traps were used. In practice, the pest did not inhabit hunting trees and only a few representatives and very small entomophagous traps fell into the traps. Instead, it inhabited healthy stands of trees, where the catchers were located. It is established that from the scientific and practical standpoint, the studied regularity of pine drying centres is clearly confined to highways and timber roads, as well as the area of distribution of relevant species of trunk pests and weakening zones of pine stands in some areas for other reasons. It is proved that to preserve the ecological potential of coniferous plantations and reduce the negative impact of xylophagous insects, it is necessary to design preventive and biological methods of control of the main trunk pests of coniferous trees

CAUSES AND CONTROL OF FRUIT CRACKING IN POMEGRANATE: A REVIEW

Pomegranate is an ancient fruit and is under cultivation through prehistoric times. Ancient and modern medical sciences have acknowledged and utilized the medicinal capabilities of pomegranate. One of the major factors limiting yield in pomegranate production is fruit splitting/cracking, losses due to fruit cracking could be as high as 40-60 percent in a given production year. Appearance of splits/cracks on fruit skin greatly reduce the yield and quality of produce. Cracked skin exposes arils to severity of environment, inset/pests, birds, microorganisms and bacterial/fungal pathogens. Stage of cracking is also an important factor as premature cracking greatly reduces yield and cracking at harvest stage reduces fruit quality, post-harvest life. This review highlights causes of fruit cracking in pomegranate and attempt is made for suggesting the best possible control for fruit cracking. In pomegranate environmental, genetic, diseases, physiological, and nutritional factors influence cracking. Varieties show variant intensity of cracking in same environmental and cultural conditions, genes responsible for cracking are reported in many fruit crops. Improper cultural practices and severity in environmental conditions, increased air temperature, moisture imbalance, hot dry winds, heavy rainfall following a dry spell and difference in day and night temperature also influence cracking. It can be reduced by selecting best suitable plants, using good orchard management and advanced production technology. This review addresses both researchers and growers as it provides necessary information about recent studies and points out the areas that need to be explored. For growers it suggests the best possible control and awareness about selection of right cultivars.

Scenario for Summer: Verses for Broadcasting

Scenario for SummerVerses for Broadcasting Paul Kane Notes for production 1. The verses spoken slowly onto a tape-recorder take approx. 20 minutes without allowance being made for music. 2. The only Section which can be omitted without destroying continuity is that entitled Flashback. 3. Titles of Sections in capital letters in the margin are not intended to be included in the broadcast reading, but are given as guide to change of voices and to voice mood. Where they occur in the text for the same reason, they are not intended to be unduly emphasised. 4. Short lines should be given their full value, although it will be found that they compose into regular, if protracted, metres. 5. Distinct preference is felt by the author for male voices in the speaking of the two parts. 6. Suggestions for Background Music: As Overture, and at end of page 2 … "En Bateaux" Debussy At beginning of Entr'acte (page 5) and at end of Afternoon (Page 6) "Golliwog's Cakewalk" Debussy Fade-out (page 9) … … … … "Clair de Lune" Debussy. Overture (First Voice) The towns where the boats come liltingly with sails to the brown wharves of Spain or the enamelled bays of Italy— they are a pale embroidery stitched in squares of rose and apricot and pearl silky in the mild sun, gathering thickly down to the tame strand of the old locked Sea. Their beauty is too rich to be taken quickly into bemused memory. Beauty wreathes [End Page 169] in vine, is ballustraded, adorned with fountain and urn and gushing grotto, lies lolling on a shallow stair and feeds on wine and gazes with warm eyes from walls stained with legend. Beauty breathes the dark pervasive scent of history. Prelude (Second Voice) That was a dream, receding. This is Australia: the plain but cheerful face, self-satisfied and unconcerned with wonders, that yelled "So long!" to the mad wanderer: and this is going back—to Summertown by the sea and knowing it stays: that blue blares like a band, blind summer feels you with dust, and a banner of wind spells Home. Welcome is a slow flat voice that calls from the boxy fibro shacks set thoughtlessly on the burnt verge of the main street like a game with faded blocks left to the sun und ruin by a bored child. This paraphernalia of wire-drums-bottles-cartons-tins tipped on the cliff proclaims with rugged ease that nature ends where civic right begins and this is a beauty-spot, the Look-Out. To help the view municipal pride has cemented a cairn of stones and gilded the dates of the great battles and the names of the brave slouching sons who fought them and died so surprisingly for the R.S.L., the Progress Association and Summertown's liberty to dump. (First Voice) You have to belong to a childhood here, to have paddled this sea when school was an iron-roofed shadow on February; or to wartime leave, days like a tender fruit found in a desert: you must have seen your firstborn make his first discovery of sand [End Page 170] on this shore: and then the eye will be lenient and affectionate as the pines that sigh like uncles reluctantly accepting the new Bar stuck like a monstrous scab on the face of bluestone. For beauty does abide here, in verandahed farms peeling in a hot wind; or stirs the gold pasture above the dune where grey sheep streal and a huge and native sky forgives our ugliness. The heart must be loving to set the small town against the dramatic bay, to see one's fellows like rustic actors shoving in the wings, and the slow play moving as sea-mist lifts the veil from a glittering day. (Music) Morning (Second Voice) The jetty's the life of the town and all the holiday boys go down at a canter on the spanking air of morning—Oh sing morning!— once there, stop, frown solemnly through the fearful yawning cracks of the jetty where green water slops, slap in the blackened hollow teeth of mussels, and great yellow strops of weed flick out, withdraw, like...

Indoor and Outdoor Particulate Matter Concentrations in the Vicinity of Plastic Waste Processing Industries

While plastic recycling has gained conclusive acceptance by various stakeholders as a preferable products’ end-of-life management, plastic waste processing industries may contribute to serious air pollutants emission and impair human health, especially if it is in uncontrolled conditions. Apart from toxic gas pollutants, this industry may also emit significant concentration of particulates matter or dust, notably via physical (shredding, sorting, and washing) and melt (re-granulation and reprocessing) processes. Meanwhile, in Sungai Petani, Kedah, Malaysia, public anguish is increasing in recent years due to mushrooming plastic waste recycling industries in its residential area. Thus, a study was conducted to analyse the day- and night-time ambient air PMio levels and their relationship with selected meteorological parameters (ambient temperature, relative humidity and wind speed) at two different locations (Cinta Sayang Resort Villa, CSRV and Metro Specialist Hospital, HM) in Sungai Petani, Kedah, Malaysia. The mean ambient PMio levels of Cinta Sayang Resort Villa (CSRV) and Metro Specialist Hospital (HM) were found exceeding the New Malaysia Ambient Air Quality Standard at 150 (μg/m3 (24-hours), which were 568.082 + 266.441 (μg/m3 615.046 + 355.672 (μg/m3, respectively. Distribution of PMio concentrations betwen day and night-time were found to be statistically insignificant at both sites. Meteorological parameters have also contributed to the trend of PMio concentrations at both sites especially at HM. Inverse correlation with PMio at CSRV was explained by the absence of moisture (or rain) at the site while the positive correlation observed at HM was due to the hot temperature-strong wind association at the site. Temperature was found to be the manipulating factor for PMio at HM, via linear regression model developed at PMouth = - 4352.426 + 170.557 x Th with F(1, 8) = 15.224 at p < .005, accounting for 65.6% of the variation Thus, proper attention should be given to the particulates matter emitted in Sungai Petani, believed to be influenced by the uncontrolled emission from the plastic recycling industries.

First record of Lichtenstein’s Sandgrouse Pterocles lichtensteinii in Lebanon, 2020

Abstract The Lichtenstein’s Sandgrouse (Pterocles lichtensteinii) is a nomadic, mostly nocturnal species. Its world range includes several countries in Africa, as far south as Kenya, and Asia as far east as Pakistan, but within the Middle East, it is a resident in Egypt, Southern Israel and Jordan, Saudi Arabia, Yemen, Oman and Southern Iran. Like other members of its family, it is found in very dry habitats including wadis and stony deserts. Seeing a flock of them in Lebanon is extraordinary. They were sighted for the first time in the country. The dry hot wind in that time of the year might have brought them there. A poacher shot the flock and killed six birds during night hunting.

Urban Overheating and Cooling Potential in Australia: An Evidence-Based Review

Cities in Australia are experiencing unprecedented levels of urban overheating, which has caused a significant impact on the country’s socioeconomic environment. This article provides a comprehensive review on urban overheating, its impact on health, energy, economy, and the heat mitigation potential of a series of strategies in Australia. Existing studies show that the average urban heat island (UHI) intensity ranges from 1.0 °C to 13.0 °C. The magnitude of urban overheating phenomenon in Australia is determined by a combination of UHI effects and dualistic atmospheric circulation systems (cool sea breeze and hot desert winds). The strong relation between multiple characteristics contribute to dramatic fluctuations and high spatiotemporal variabilities in urban overheating. In addition, urban overheating contributes to serious impacts on human health, energy costs, thermal comfort, labour productivity, and social behaviour. Evidence suggest that cool materials, green roofs, vertical gardens, urban greenery, and water-based technologies can significantly alleviate the UHI effect, cool the ambient air, and create thermally balanced cities. Urban greenery, especially trees, has a high potential for mitigation. Trees and hedges can reduce the average maximum UHI by 1.0 °C. The average maximum mitigation performance values of green roofs and green walls are 0.2 °C and 0.1 °C, respectively. Reflective roofs and pavements can reduce the average maximum UHI by 0.3 °C. In dry areas, water has a high cooling potential. The average maximum cooling potential using only one technology is 0.4 °C. When two or more technologies are used at the same time, the average maximum UHI drop is 1.5 °C. The mitigation strategies identified in this article can help the governments and other stakeholders manage urban heating in the natural and built environment, and save health, energy, and economic costs.