Performance Study of Dynamic Intake and Exhaust Fa鏰des in Hot and Dry Climates:Iraq Case Study

This paper is part of a series addressing the urgent need for effective technologies to reduce energy demand and mitigate climate impact.This study focused on the implementation and development of dynamic insulation technology for a sustainable and energy-efficient future in the region,especially in Iraq.The study assessed the energy efficiency of dynamic insulation technology by analyzing three wallmodels(static,dynamic,and modified)during thewinter season.This paper expands the analysis to include a hot,dry summer scenario,providing valuable insights into the year-round performance of dynamic walls and enabling sustainable and energy-efficient solutions for Iraq’s climate.The study evaluates the thermal efficiency of the dynamic intake and exhaust facades during the cooling season for the city of Baghdad.The finding indicated that the dynamic intake facade reduces energy consumption by 16.3%for the dynamic wall and 17.2%for the modified dynamic wall.In addition,the dynamic exhaust front reduces energy consumption by 46%during the cooling season,with the maximum permissible exhaust air level.Dynamic insulation is suitable for hot and dry climates,improving energy consumption.

Tropical Climates May Be Suitable for Endangered Desert Tortoise Exhibits, Rescues, Adoptions

Governmental, educational, environmental and other nonprofit organizations have placed efforts on conservation action for the threatened Mojave desert tortoise (Gopherus agassizii). While federal and state institutions have focused on the desert tortoise in its native habitat of the southwestern United States, there are other conservation groups whose work has been dedicated to the rescue, rehabilitation, rescue, placement and adoption of the desert tortoise in civilian homes and neighborhoods as well as sanctuaries, reserves and exhibits. AWAKE Community (AWAKE), a nonprofit organization dedicated to natural wildlife habitats and endangered species, has focused its research on desert tortoises in captivity. The California Turtle and Tortoise Club (CTTC), the official adoption arm of California’s Department of Fish and Wildlife (CDFW), has provided instruction on methods of care for desert tortoises raised in captivity including housing, feeding, sexing, health and hibernation for both adults and hatchlings. AWAKE’s research has been aimed at benefiting and supplementing the guidelines provided by CTTC, specifically for coastal climates. AWAKE’s research has also aimed to provide insight to be considered for expanding adoption possibilities to other locations, specifically tropical climates, as adoption needs for desert tortoises have increased. This manuscript presents an analysis of one coastal and one tropical climate that can serve as a basis for: 1) understanding and evaluating climate in both existing and potential habitats for desert tortoise adoptions, rescues and exhibits, 2) providing insight and special instruction for desert tortoise adoptions in coastal communities, and 3) expanding awareness around desert tortoise needs in captivity.

A Spectrally Selective Window for Hot Climates

Rigorous coupled-wave analysis has been used to design a glazing for hot climates. The designed glazing is relatively simple and it transmits most of the visible light and reflects most of the infrared radiation. It does not need any external source of energy to control its optical properties. It consists of ITO and four periodic pairs of Si/SiO2, deposited on a glass sheet. The optimum thicknesses of ITO, Si and SiO2 are 0.1 μm, 0.15 and 0.4 μm, respectively. The glazing acts as an optically selective filter. It transmits about 80% of the visible light and reflects almost all the infrared radiation. The performance of the glazing is almost independent of the angle of incidence of solar radiation. This makes it suitable for all hours of the day. The fabrication of the glazing and the testing have been performed at the laboratories of the Faculty of Science, University of Witwatersrand, South Africa. Magnetron sputtering technique has been used for the fabrication. ITO, Si and SiO2 have been used as sputtering targets. The experimental results are almost identical to the simulation results.

Zero-Energy-Buildings in Different Climates： Design Strategies, Simulation and Prognosis METHOD for Energy Demand

The European Directive 2010/31 claims that by 2020 only （nearly-） ZEB （zero-energy-buildings） may be built. To reach this goal, it is pertinent for buildings to be energetically optimized first. The remaining energy demand must then be covered by on-site renewable energies （PV, geothermal, etc.）. With the area of use （energy demand） and the size of the building envelope/estate （renewable energy supply） in competition with each other, the maximum number of building stories will be most likely limited. For 15 different climatic locations worldwide, the energy demand of optimised office rooms has been simulated and compared with the possible renewable energy production on site. For every location, a good correlation has been found between the simulated energy demand and data like heating and cooling degree hours. Correspondent linear equations are given here. As another result, the maximum numbers of possible stories for ZEBS have been derived, being between 3 and 10 depending on the location.

Spatial distribution of air temperature and relative humidity in the greenhouse as affected by external shading in arid climates

The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, Saudi Arabia. Two identical, evaporatively-cooled, single-span greenhouses were used in the experiment. One greenhouse was externally shaded(Gs) using a movable black plastic net(30% transmissivity), and the other greenhouse was kept without shading(Gc). Strawberry plants were cultivated in both greenhouses. The results showed that the spatial distribution of the Tin and RHin was significantly affected by the outside solar radiation and evaporative cooling operation. The regression analysis showed that when the outside solar radiation intensity increased from 200 to 800 W m–2, the Tin increased by 4.5℃ in the Gc and 2℃in the Gs, while the RHin decreased by 15% in the Gc and 5% in the Gs, respectively. Compared with those in the Gc, more uniformity in the spatial distribution of the Tin and RHin was observed in the Gs. The difference between the maximum and minimum Tin of 6.4℃ and the RHin of 10% was lower in the Gs than those in the Gc during the early morning. Around 2℃ difference in the Tin was shown between the area closed to the exhausted fans and the area closed to the cooling pad with the external shading. In an evaporatively-cooled greenhouse in arid regions, the variation of the Tin and RHin in the vertical direction and along the sidewalls was much higher than that in the horizontal direction. The average variation of the Tin and RHin in the vertical direction was 5.2℃ and 10% in the Gc and 5.5℃ and 13% in the Gs, respectively. The external shading improved the spatial distribution of the Tin and RHin and improved the cooling efficiency of the evaporative cooling system by 12%, since the transmitted solar radiation and accumulated thermal energy in the greenhouse were significantly reduced.

Projected changes in mean and extreme climates over Hindu Kush Himalayan region by 21 CMIP5 models

Based on the outputs from 21 CMIP5 (Coupled Model Intercomparison Project phase 5) models, future changes in the mean temperature, precipitation and four climate extreme indices (annual maximum of daily maximum temperature (TXx), minimum of daily minimum temperature (TNn), annual total precipitation when the daily amount exceeds the 95th percentile of wet-day precipitation (R95p), and maximum consecutive 5-day precipitation (RX5day)) over Hindu Kush Himalayan (HKH) region are investigated under the greenhouse gas concentration pathways of RCP4.5 and RCP8.5. Two periods of the 21st century, 2036e2065 and 2066e2095, are selected, with the reference period is considered as 1976e2005. Results show general increase of the mean temperature, TXx and TNn under both scenarios, with the largest increases found during 2066e2095 under RCP8.5. Future precipitation is projected to increase over most part of HKH, except for the northwestern part. Intensification of the precipitation extremes is projected over the region. The uncertainties of mean temperature, TXx and TNn over the HKH1 subregions are the largest compared to the other three subregions and the overall HKH. Besides RX5day during 2036e2065 over HKH1, the uncertainties of R95p and RX5day tend to be larger following the increase of greenhouse gas concentrations. The multimodel ensemble medians of temperature and four extreme indices under RCP8.5 are projected to be larger than those under RCP4.5 in each of the subregions.

Picea species from humid continental and temperate marine climates perform better in monsoonal areas of middle latitudes of China

Picea spp.are a prominent component of the boreal,montane,and sub-alpine forests in the Northern Hemisphere,and have substantial economic importance due to their high quality fibre.However,performance and wood properties of the genus have not been systematically evaluated in China.This study aimed to examine genetic variations in growth traits,phenology,and wood properties of 17 Picea species,(three from North America,two from Europe,and 12 from China),in response to specific climate factors using a randomized complete block design in a monsoonal,middle latitude area of China.Results show that all growth traits and wood properties significantly varied among species(P <0.00).Of the 17 species examined,P.abies and P.pungens were the tallest with heights of 2.5 and 1.9 m at 9 years old,respectively,90% and 50% greater than the average heights.Branch length,number,and angles of both P.abies and P.pungens were greater than those of the other species.Heights of P.glauca and P.omorika were20-33% greater than the average.Fast-growing species had high quantities of first lateral branches and large top whorl branch lengths.The taller species exhibited greater tracheid lengths and average tracheid lengths to radial central diameter ratios(TL/R_D2),but smaller cell wall thicknesses to tracheid radial lumen diameter ratios(WT/R_D1),which is favorable for pulp production.Correlation analysis revealed that height and ring width had significant positive correlations with latitude but strongly negative correlations with longitude.Height was positively correlated with average annual rainfalls,but negative correlations with average yearly sunshine.Due to the increased average annual sunshine at the China test site relative to the seed source,species such as P.abies,P.pungens,P.glauca,and P.omorika from wet,humid areas performed better than native species.Considering similar temperatures,precipitation may be the main factor affecting growth,which is beneficial for predicting the extent of spruce expansion.These results should encourage further testing and provide reference information for future exotic species studies in this part of China.

Quantifying the effect of persistent dryer climates on forest productivity and implications for forest planning:a case study in northern Germany

Background: Forest management decisions are based on expectations of future developments. For sound decisions it is essential to accurately predict the expected values in future developments and to account for their inherent uncertainty,for example the impact of climate change on forests. Changing climatic conditions affect forest productivity and alter the risk profile of forests and forest enterprises. Intensifying drought stress is seen as one major risk factor threatening forest management in the north German lowlands. Drought stress reduces tree growth and vitality and might even trigger mortality. But so far, it is not possible to quantify effects of a persistent dryer climate on forest productivity at a level suitable for forest management.Methods: We apply a well-established single-tree forest growth simulator to quantify the effect of persistent dryer climates on future forest productivity. We analyse the growth of Scots pine(Pinus sylvestris L.), European beech(Fagus sylvatico L.) and oak(Quercus robur L. and Quercus petraea(Matt.) Liebl.) in two forest regions in the north German lowlands for a time interval of 60 years until 2070. The growth response under three different climate projections is compared to a baseline scenario.Results: The results show clear differences in volume increment to persistent dryer climates between tree species. The findings exhibit regional differences and temporal trends. While mean annual increment at biological rotation age of Scots pine and oak predominantly benefits from the projected climate conditions until 2070, beech might suffer losses of up to 3 m^3·ha^(-1)yr^(-1) depending on climate scenario and region. However, in the projection period2051 to 2070 the uncertainty ranges comprise positive as well as negative climatic effects for all species.Conclusions: The projected changes in forest growth serve as quantitative contributions to provide decision support in the evaluation of, for example, species future site suitability and timber supply assessments. The analysis of productivity changes under persistent dryer climate complements the drought vulnerability assessment which is applied in practical forestry in northwestern Germany today. The projected species' productivity has strong implications for forest management and the inherent uncertainty needs to be accounted for.

Modeling nonstationary extreme wave heights in present and future climates of Greek Seas

In this study the generalized extreme value （GEV） distribution function was used to assess nonstationarity in annual maximum wave heights for selected locations in the Greek Seas, both in the present and future climates. The available significant wave height data were divided into groups corresponding to the present period （1951-2000）, a first future period （2001-2050）, and a second future period （2051-2100）. For each time period, the parameters of the GEV distribution were specified as functions of time-varying covariates and estimated using the conditional density network （CDN）. For each location and selected time period, a total number of 29 linear and nonlinear models were fitted to the wave data, for a given combination of covariates. The covariates used in the GEV-CDN models consisted of wind fields resulting from the Regional Climate Model version 3 （RegCM3） developed by the International Center for Theoretical Physics （ICTP） with a spatial resolution of 10 km ×10 km, after being processed using principal component analysis （PCA）. The results obtained from the best fitted models in the present and future periods for each location were compared, revealing different patterns of relationships between wind components and extreme wave height quantiles in different parts of the Greek Seas and different periods. The analysis demonstrates an increase of extreme wave heights in the first future period as compared with the present period, causing a significant threat to Greek coastal areas in the North Aegean Sea and the Ionian Sea.

Effect of contrasting climates on antioxidant and bioactive constituents in five medicinal herbs in Western Himalayas

To understand the effect of climate change on constitutive antioxidant and biochemical metabolites in Western Himalayas, five medicinal herbs were selected and grown at two altitudes in Jammu(305 m) and Srinagar(1730 m) with subtropical and temperate climates, respectively.Significant variations were observed in phenols and flavonoids in Hypericum perforatum L., Matricaria chamomilla L., Thymus vulgaris L., Cynara cardunculus L. and Echinacea purpurea L. growing at two locations. High altitude temperate site show variable(up to 13 fold) increase in their content.Proteins(1.3- 1.8 times), sugars(2.8- 4.1 times) and free amino acid(1.04- 1.22 times) were also higher at Srinagar(1730 m). Within these plants, H.perforatum and M. chamomilla have shown higher accumulation of phenols, xanthophylls and proline even at subtropical environment in Jammu(305 m)suggesting potential for increasing their geographical area. The results demonstrate that changing environmental conditions significantly affect the bioactive constituents, which accumulate as a defence strategy by these temperate plants. Their medicinal significance during climate change scenario has also been discussed.

Climatic change in Western North America during the last 15,000 years:The role of changes in the relative strengths of air masses in producing the changing climates

In the Cordillera of western North America, the influence of the Pacific Interdecadal Oscillation only affects coastal areas west of the Coast Range and the lowlands of western and southern Alaska. The rest of the area is subject to a climate controlled by the relative strengths of three distinct air masses, viz., the cold cA/cP air that is dominant in winter, the mP air bringing cool moist air over the mountains throughout the year, and the dry hot cT air from the deserts of the southwestern United States. The Arctic Front marks the boundary between the cA/cP air mass and the other two. Changes in the relative strengths of these air masses appear to explain the climatic changes documented throughout the region. Thus, in the last 30 years, the average position of the Arctic Front has moved north from about 53°N to 58°N, causing the warming in northern British Columbia and cooling south of Calgary, Alberta. This concept of changing positions of the air masses also appears to explain the mechanism behind the past climatic changes in this region. During the last Neoglacial event （c.1400-1900 A.D.）, it appears that the cA/cP air mass had strengthened enough to push the Arctic Front south of the 49th parallel. Incursions of mP air increased with localized areas of short-term heavy snowfalls resulting in small-scale advances of glaciers in these regions. This accounts for the variability in timing and extent of these glacial advances, while the resulting increased Chinook activity produced the development of a sand sea between Medicine Hat and Regina on the southern Prairies. The cT air mass was relatively weak, permitting these changes. During the maximum of the Altithermal/Hysithermal warm event （6,000 years B.P.）, the Arctic Front had retreated into the southern Yukon Territory as the cT air mass became stronger. The mP air could not move inland as easily, resulting in drier climates across the region. Prairie plants mi- grated into the southern Yukon Territory, and land snails from the eastern United States were able to migrate up the Saskatchewan River system as far as Lake Louise, Alberta. On the southern Prairies, the many small sloughs and lakes dried up. During the maximum of the Late Wisconsin Glacial event （15,000 years B.P.）, the Arctic Front had moved south to the vicinity of 30°N, while there had been a southward movement of the Zone of Intertropical Convergence from the equator to about 10°S. The mP air was also very strong and dumped enormous quantities of snow in the glaciated Canadian Cordillera, but it does not appear to have moved south any distance into the northern United States, witness the limited glaciation and widespread permafrost that developed there. Instead, there is evidence for buffering of the climatic changes in the closed basins in the northern Cordillera of the contiguous United States. The source of the cT air mass had moved south into the northern part of South America, permitting an exchange of savannah biota between the two continents. An extensive area of white dune sands inundated both savannah and forest along the inland hills in Guyana. This parallels the massive changes in African climatology during the last Ice Age （Fairbridge, 1964）. If these changes occurred each time there was a major glaciation in the Northern Hemisphere, this would explain the movement of biota from all terrestrial environments between the two American continents in the last 2 million years. A similar northward movement of climatic belts occurred in South America, with the cA air from Antarctica expanding northwards into southern Argentina and Chili. However paucity of data and the potential effects of El Ni o and the Southern Oscillation make it difficult toprovide details of the changes there in the present state of knowledge. This technique of studying the mechanisms of present-day climatic changes and applying the results to past climatic events has considerable potential for elucidating past climatic changes elsewhere in continental regions. This may prove particularly valuable in studying the Siberian anticyclone that is the main cause of the distribution of permafrost, but this will need international cooperation to be successful.

A STUDY ON THE ECOLOGICAL CLIMATES OF SOME FAMOUS TEA GROWING AREAS IN HIGH MOUNTAINOUS REGIONS OF CHINA

The tea tree [Camellia sinensis (L) Kuntze] is one of the world’s economic crops. It is an especially important crop for southern China. Environmental factors related to the tea yield and quality in some high mountain areas of China are identified in this paper. These factors are: geology, topography, climate, hydrology, soil and vegetation. Climatological factors are the most important. Using data collected from meteorological stations which are situated at the summit and the base of high mountains, this paper discusses ecological climatic problems in growing tea in China. The ecological climatic characteristics of the famous tea areas mainly included are as follows: more . amounts of clouds and fog, less percentage of sunshine, abundant rainfall and high relative humidity in the air, temperatures that rise and fall slowly, daily and annual temperature ranges that are smaller, more days that are suitable for tea growing and low wind speeds in the lee-sides and valleys of mountains. All of these

The Anomalous European Climates Linked to Different Euro-Atlantic Blocking

The impact on temperature and precipitation anomalies over the European continent of the different action centers of blocking events in the Euro-Atlantic sector was investigated. It was found that the position of the blocking action center in the Euro-Atlantic region seems to dominate European climates. When the center of the blocking action is in the Greenland region, there is a strong negative temperature anomaly over Central and Northern Europe, as well as a strong positive precipitation anomaly over southern Europe. However, there tends to be a strong negative temperature anomaly in the west(east) part of Europe when the center of the blocking action is shifted to the Eastern Atlantic and west Europe(east Europe). In particular, when the blocking action center is closer to the European continent, the fall in temperature becomes more evident over Central and south Europe than over other regions. Moreover, it was found that when the region where the blocking action center exists changes from the Eastern Atlantic and west Europe region to the east Europe region, the existing region of dominant positive precipitation anomalies varies from southwest Europe to southeast Europe and the Middle East.

METHODS OF ENHANCING ETHICAL CLIMATES IN THE ORGANIZATION AND A CASE STUDY OF BUSINESS IN TAIWAN

This study involves the compilation of related Chinese and Western literature to complement an initial understanding of the enhancing methods of ethical climate in the organization. Six companies are selected as the objects of the measurements, in order to understand their responses to the methods.

About A New Complex Method of Climates Reconstruction and Forecasting of Climate Changes in the Future

This paper deals with a new integrated method of reconstruction and forecasting of climatic changes in future. The method is based on proxy data pollen-spore analysis method, 14C analysis method, nowadays meteorological data, and data about of solar activity expressed in numbers of W （Wolf）. Here we present the results of investigation of sediments of the 2nd Fomich River terrace, Taymyr Peninsula, Russia. The formation of the peat bog started 10500 ± 140 years BP and continued during the entire Holocene. The pollen analysis of the sediment samples of the 2nd Fomich River terrace and the analysis of surface samples from a larch forest, typical of this region, reveals two phytochrones： both climatically preconditioned--tundra phytochrone （I1-4） and forest phytochrone （Ⅱ1-4）. The techniques of reconstruction and forecasting of basic elements of climate are presented and discussed in details.

Planetary Layer Lapse Rate Comparison of Tropical, Montane and Hot Semi-Arid Climates of Nigeria

This study assessed the pattern of planetary layer lapse rate across the major climate belts of Nigeria.Six years’data(2010-2015)for air temperature values between 1000 mbar and 850 mbar atmospheric pressure levels was acquired from Era-Interim Re-analysis data centre.The data was retrieved at 6-hourly synoptic hours:00:00 Hr,06:00 Hr.at 0.125o grid resolution.Results showed that the lower tropospheric layers throughout the various climate belts has a positive lapse rate.Findings also revealed that the average annual lapse rate condition were:Tropical wet zone(Port Harcourt)-5.6 oC/km;Bi-modal Tropical continental zone(Enugu)-5.8 oC/km;Montane zone(Jos)-6.5 oC/km;Mono-modal Tropical continental zone(Kano)-6.6 oC/km;and Hot semi-arid zone(Maiduguri)-6.6 oC/km.This average values presents the lapse rates to be near the Saturated Adiabatic Lapse Rate(SALR).Average diurnal results for the climate belts showed that lapse rate is higher during the afternoon and transition periods than the rest periods and increases from the coastal areas northward.The seasonal periods of highest lapse rates during the day time are from December-May(i.e.-5.8-9.5 oC/km)with slight decrease from June-November.The positive lapse rates of range-1.8 to 5.9 oC/km observed during the period of dawn across the entire region showed that infrared radiation was still being released and modified by less energetic mechanical turbulence that characterizes the surface layer across Nigeria.This also indicate that global warming is real and in substantial effect.The study findings imply that conditional instability prevailed over the entire region,therefore,the planetary layer environment will be of slow to moderate dispersive potential and will require forceful mechanism to lift emissions introduced into it.It is recommended that industrial stacks should be above 50 m to enhance the dispersion of emissions aloft.

Impacts of major volcanic eruptions over the past two millennia on both global and Chinese climates:A review

Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific community.Previous studies have explored the climatic impact of MVEs over the past two millennia.However,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to MVEs.Here,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future research.We reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 CE.After tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and simulations.In the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is observed.In reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of China.Decadal drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal variability.MVEs affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction disagreements.Moreover,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction disagreements.Knowledge gaps and directions for future research are also discussed.

ENVIRONMENTAL IMPACT OF COURTYARDS-A REVIEW AND COMPARISON OF RESIDENTIAL COURTYARD BUILDINGS IN DIFFERENT CLIMATES

Purpose-This paper tries to clarify the environmental impacts of a traditional building form which was developed more than 5000 years ago,under the force of harsh hot climates:courtyard building.A courtyard is an outdoor space which is entirely surrounded by buildings or walls.The main purpose is to show if this building form can reduce the energy demand of low-rise residential buildings in order to reduce CO_(2) emission which generally considered is the main root of climate change.Methodology-From a literature review on courtyard buildings several climatic aspects of this building form can be extracted.In this step,the paper focuses on the climatic impact(s)in the context of hot-arid,snow,temperate and tropical climates.Findings-Results for different configuration of courtyard building,natural elements used in it,and the situation of openings in different facades are the most important findings of this review paper.Research limitations-The research is limited to considering residential courtyard buildings in four climates;hot-arid,snow,temperate,and tropical(based on Koppen-Geiger climate classification).Practical implications-The results of the paper are general climatic characteristics of courtyard buildings.These characteristics can be used for designing new courtyard dwellings.Innovation-Although the background information of the paper is based on literature,the innovation is the comprehensive consideration and comparison of environmental characteristics in different climates which has never been done before.

EVALUATING WINDOW INSULATION FOR COLD CLIMATES

INTRODUCTION In cold climates,a large amount of heat is lost through windows during the winter.For instance,a double-pane window might allow as much as 10 times the amount of heat to leave a house compared to the same area of a typical 2×6 wall.It makes sense to upgrade or insulate windows in order to improve the thermal envelope of a home,especially in an area with a long heating season;however,windows are a very expensive component of the building envelope to replace.Replacing a single window can cost several hundred to more than a thousand dollars;therefore,people often resort to cheaper methods to reduce heat loss,such as shutters or curtains.Others may already have high-performance windows,but want to reduce heat loss even further by placing movable insulation over their windows during the cold winter nights.To help guide these decisions,the Cold Climate Housing Research Center(CCHRC)in Fairbanks,Alaska,conducted a study of common window insulation methods and compared them in terms of thermal effectiveness,affordability,ease of installation,durability,functionality,and condensation resistance.The purpose of the study was to inform homeowners about the various advantages and disadvantages of different window treatments.As part of the research,CCHRC studied a variety of methods and windows in volunteers’homes to understand how the methods work in real-life situations.CCHRC also modeled the retrofit window treatments with Therm 6.3,a modeling program,to help explain more generally how they can help homeowners.

EFFECT OF BUILDING PLAN FORM ON HUMAN THERMAL COMFORT IN NATURALLY VENTILATED OPEN-PLAN ENCLOSURES LOCATED IN HOT CLIMATES

This study aims to examine the effect of building plan form on internal thermal comfort conditions in naturally ventilated open-plan buildings located in hot climates.The study examined the square and the rectangular plan forms in relation to several values of wind direction,building plan depth,and climatic conditions.The study utilised CFD for ventilation prediction,DesignBuilder for thermal modelling,and the Tropical Summer Index(TSI)for thermal comfort assessment.These three tools were integrated in a quantitative approach to fulfil the study aim.The study concluded that the use of area-weighted average velocity magnitude is more accurate in the assessment of natural ventilation performance,as it accounts for both internal velocity magnitude and distribution.The study confirmed the common observation that the use of shallow building plans is more effective to increase internal air velocity and improve internal thermal comfort.At some point of increased plan depth,the internal air velocity magnitude dramatically decreases.In the three examined wind directions,this occurred when the plan depth exceeded 3H in the square cases and 2.5H in the rectangular ones,where H is the building height.This value is much less than the commonly recommended maximum value of 5H.The study also concluded that reducing building depth in the square cases has generally more potential to improve thermal comfort conditions when compared with the rectangular cases.The gross increase in Percentage of People Comfortable,PPC,in all the examined cases was 23%in the square cases,compared to 11%in the rectangular cases.