Equatorial Climate Research Articles

Rainfall Variability and Trends over the African Continent Using TAMSAT Data (1983–2020): Towards Climate Change Resilience and Adaptation

This study reveals rainfall variability and trends in the African continent using TAMSAT data from 1983 to 2020. In the study, a Mann–Kendall (MK) test and Sen’s slope estimator were used to analyze rainfall trends and their magnitude, respectively, under monthly, seasonal, and annual timeframes as an indication of climate change using different natural and geographical contexts (i.e., sub-regions, climate zones, major river basins, and countries). The study finds that the highest annual rainfall trends were recorded in Rwanda (11.97 mm/year), the Gulf of Guinea (river basin 8.71 mm/year), the tropical rainforest climate zone (8.21 mm/year), and the Central African region (6.84 mm/year), while Mozambique (−0.437 mm/year), the subtropical northern desert (0.80 mm/year), the west coast river basin of South Africa (−0.360 mm/year), and the Northern Africa region (1.07 mm/year) show the lowest annual rainfall trends. There is a statistically significant increase in the rainfall in the countries of Africa’s northern and central regions, while there is no statistically significant change in the countries of the southern and eastern regions. In terms of climate zones, in the tropical northern desert climates, tropical northern peninsulas, and tropical grasslands, there is a significant increase in rainfall over the entire timeframe of the month, season, and year. This implies that increased rainfall will have a positive effect on the food security of the countries in those climatic zones. Since a large percentage of Africa’s agriculture is based only on rainfall (i.e., rain-fed agriculture), increasing trends in rainfall can assist climate resilience and adaptation, while declining rainfall trends can badly affect it. This information can be crucial for decision-makers concerned with effective crop planning and water resource management. The rainfall variability and trend analysis of this study provide important information to decision-makers that need to effectively mitigate drought and flood risk.

Trends and Rhythms in Climate Change During the Early Permian Icehouse

AbstractLate Paleozoic deglaciation is the first icehouse‐to‐greenhouse transition in a world with expansive tropical forests, but the detailed process of this climatic upheaval is still debated due to lack of high‐precision global correlation. Here, based on the cyclostratigraphic analysis of a deep‐marine succession of Naqing in South China, chronostratigraphic correlation was achieved between Paleo‐Tethyan deep‐marine carbonate cyclicity and U‐Pb zircon age‐calibrated cyclothems from the Pangaean paleotropics. Refining the global chronostratigraphy indicates ages of 294.1 ± 0.2 Ma and 290.1 ± 0.2 Ma for the base of the Sakmarian and Artinskian stages, respectively. We juxtapose the climatic proxies and indicators across blocks and latitudes to decipher the trends and rhythms in climate change during a period from the apex of the Late Paleozoic ice age (LPIA) to the initial deglaciation. On the multiple‐million‐year time scale, the polar and equatorial climates were linked through the atmospheric pCO2 control. A rise in pCO2 promoted Gondwanan deglaciation and tropical aridification. The disparity in the inferred polarity of tropical climate changes during glacials and interglacials has been confirmed on the million‐year time scale. The meridional flux of moisture was enhanced during the minima of the ∼1.2 Myr obliquity cycle, periodically resulting in Gondwanan glaciation, glacio‐eustatic sea‐level lowerings, and reduced moisture availability in the tropical Pangaean and Paleo‐Tethyan regions. Our study provides an improved temporal resolution and understanding of the apex of the LPIA.

Quality reference values for trace metals in Podzols, Ferralsols, and Acrisols of Brazilian Atlantic rainforest

In tropical coastal forest ecosystems, human activities spread rapidly. It is, therefore, necessary to define soil quality. For this, the determination of the natural content of trace metals is an essential step. This study aims to understand the distribution of trace metals in the main soils of tropical coastal rainforest ecosystems: Ferralsols, Acrisols, and Podzols, in Bahia state, Brazil. After morphological, chemical, and physical characterization and classification of the soils, the concentration of trace metals was investigated both in soil profiles and in surface composite samples (national guideline recommendation), in five locations for each soil class. The soils were classified as Geric Ferralsol, Haplic Acrisol, Chromic Acrisol, and Ortsteinic Carbic Albic Endogleyic Podzol. Concentrations of metals differed significantly between soil classes. Even under tropical rainforest climate during soil formation, the parent rock material still influences geochemistry. Al, Fe, Mo, Ni, V, and Zn accumulate in Ferralsols, while Ba, Co, Cr, Cu, and Mn accumulate in Acrisols. In the Podzols, metals highly accumulate in B spodic horizon. The data highlights that composite sampling strictly based on soil layers and not horizons (as the national guideline recommends) can cause significant misinterpretations. Instead, the multivariate regression models provided consistent data, accurately predicting the pseudo-total concentrations of trace metals in individual soil samples. The regression method is fast and low cost and provides a reliable geochemical baseline for the definition of reference values.

Deriving a denudation index for terrestrial meteorite impact craters using drainages as proxies

Meteorite impact craters are morphologic features that can develop characteristic radial, centripetal, and concentric drainage patterns. With age, fluvial activity denudes this morphologic feature, thereby erasing the evidence of a prominent geologic event. Apart from morphology and age, the target lithology and climate also influence crater denudation. In this study, we derive an index, called the Denudation Index (DI), which is a measure of rim degradation caused by fluvial activity. DI was derived by summing the average of first order drainages that retains radial and centripetal patterns to the total number of streams. DI was obtained through the extraction of drainages from digital elevation models (DEM) for 71 craters formed since the Phanerozoic eon. The DI was correlated with the morphology, age, lithology and paleoclimate. Paleoclimatic data corresponding to each crater was generated by reconstructing the crater paleo-positions through GPlates and superimposing the same to the Scotese's Global Climate Model with an interval of 1 Ma. The study revealed that denudation is more prominent in a complex crater's formation on a crystalline target rock than in simple crater on a sedimentary target. Craters in the equatorial rainy climate are more denudating than other climates. Thus, this study provides a new, rather novel, method of expressing the denudation of a crater. Furthermore, this study shows that the drainage network is a unique signature that can be used for depicting the denudation of morphologic features, especially a prominent one like the meteorite impact crater.

Occurrence of some campanian-maastrichtian organic-walled microfossils from Enugu Shale, Anambra Basin, Southeastern nigeria: Implications for age and paleoenvironments

Detailed geological field mapping and sampling of the Enugu Formation in the Anambra Basin has been carried out in order to re-examine the age of sediments and reconstruct their paleoenvironments of deposition. A total of ten (10) outcrop samples of shale were subjected to palynological laboratory examination, using conventional method of acid demineralization and maceration techniques for recovering acid-insoluble organic-walled microfossils from sediments. Two main lithological units were distinguished: - carbonaceous fissile shale and siltstone. A late Campanian - Earliest Maastrichtian age was assigned based on index palynomorphs marker taxa Longapertites marginatus (overwhelming abundance), Monocolpites marginatus, Zlivisporis blanensis, and Echitriporites trianguliformis. The age designation was strengthened by the occurrence of a well-known stratigraphic age-diagnostic organic-walled microplankton Coronifera tubulosa, Senegalinium spp. and Andalusiella polymorpha. Palynomorphs of environmental value include Cyathidites minor, (a tree fern of wet, forested, tropical to temperate regions, usually most developed in mountainous / highland terrains under moist and equable climate); Spinizonocolpites baculatus/echinatus, Longapertites marginatus, Mauritidites crassibaculatus and Moncolpites marginatus, which are palm pollen that inhabit similar brackish water as the mangrove. A non-marine to marginal marine depositional setting has therefore been proposed for the Enugu Formation.

A low-cost monitoring system of stem water content: Development and application to Brazilian forest species

The storage of water in the plant and its impacts on eco-hydrological processes are not commonly considered in the models for estimating plant transpiration and evapotranspiration. The high costs required for a wide monitoring network are major obstacles to obtain more consistent results. The aim of the present study is to build and evaluate a low-cost system for the continuous monitoring of stem moisture content (SM). After constructing and calibrating the stem moisture sensors, they were used to monitor plants of the paricá (Schizolobium amazonicum) and catingueira (Caesalpinia pyramidalis Tul.). The paricá was studied in equatorial climate conditions while the study with the catingueira was carried out in a tropical semiarid condition. Three individuals of the paricá and four of the catingueira were selected for monitoring the SM. The stem moisture sensor probe that was developed showed a small error (less than 4.8% in 95% of measurements) compared to the gravimetric method, and can be used to monitor SM in other species as well as those under study, as long as prior calibration is carried out. In a field experiment, the probe enabled the SM response to be studied in two species with fairly different wood densities and moisture content, in environments of contrasting soil and climate characteristics.

Simultaneous investigation of surface and canopy urban heat islands over global cities

Interpreting the similarities and dissimilarities in spatiotemporal variations and various controls between surface and canopy urban heat islands (UHIs) is critical for a better understanding of their vertical structure. Preceding comparisons of the surface UHI (SUHI) and canopy UHI (CUHI), however, remain mostly restricted either in a single city or over a few cities within limited background climates; therefore, the associated similarities and dissimilarities between the SUHI and CUHI under different climates, especially at a global scale, remain largely unknown. Based on both satellite and in situ data, we simultaneously investigated the spatiotemporal patterns of the SUHI intensity (SUHII) and CUHI intensity (SUHII) of 366 global cities within various background climates. We further investigated the different impacts of several controls (e.g., vegetation coverage, population size, precipitation) on SUHII and CUHII. Our results indicate the following: (1) For the selected 366 cities, the annual mean SUHII is higher than CUHII by 1.1 ± 1.9 °C (mean ± Std) during the day and 0.3 ± 1.5 °C (mean ± Std) at night. The SUHII and CUHII in the equatorial, warm temperate, and snow climates are generally consistent with the above characteristics (i.e., SUHII > CUHII), however, in arid regions SUHII is lower than CUHII by 0.8 °C during the day. (2) The annual mean day–night difference in SUHII is positive (i.e., 0.6 ± 1.8 °C (mean ± Std)), while the difference in CUHII becomes negative (i.e., −0.2 ± 1.6 °C (mean ± Std)), indicating that urbanization increases the diurnal temperature range (DTR) based on land surface temperature, but it decreases the DTR based on surface air temperature. (3) Despite the high correlation between vegetation coverage and impervious surface percentage (ISP), their impacts on SUHII and CUHII were not consistent. The urban–rural difference in ISP exerts an insignificant impact on both SUHII and CUHII during the day and a greater impact on CUHII than on SUHII at night, whereas the urban–rural difference in vegetation coverage has a greater impact on SUHII than on CUHII during the day, while the opposite occurs at night. The impacts of population size on SUHII and CUHII are much greater during the night than on the day in which their impacts can be minimal. The relationship between annual mean precipitation and SUHII is positive during the day but negative at night, while for CUHII, their relationship is insignificantly negative both during the day and at night. These results can improve our understanding of the spatiotemporal patterns and controls of these two types of UHIs under various climates.

A framework for the development of hemp (Cannabis sativa L.) as a crop for the future in tropical environments

Hemp (Cannabis sativa L.) is a multipurpose industrial crop which is mainly cultivated in temperate regions. With its high potential for economic returns for its seeds and fiber, there is growing interest in cultivating hemp in many territories including Malaysia and other Asian countries, where its cultivation is currently illegal. To date, no comprehensive study on the suitability of this crop under Malaysian conditions has been conducted. In this paper, we propose an assessment framework as a roadmap to develop the hemp industry in Malaysia and possibly other Asian countries with equatorial climates. This framework includes suitability assessment (climate and soil), crop modelling (current and future yields under climate change) and economic analysis (net present value (NPV), NPV benefit (NPVB) and benefit-cost ratio (BCR). The land suitability assessment classified hemp as an adaptable crop for most of the land in the country. The AquaCrop model, parameterised from secondary data collected from literature was used in simulations and potential yield mapping. The estimated average potential seed and fiber yield at six locations between 2010 and 2019 was 1.61 ± 0.25 and 2.78 ± 0.39 t ha–1 respectively. Using five general circulation model (GCM) simulations, yields under future climates in Malaysia showed an increase in most of the locations. The highest NPVB of 1641 USD ha–1 (BCR of 1.33) for seed was estimated under current climate conditions. Yields of 1.38 t ha–1 (seed) and 3.62 t ha–1 (fiber) are the minimum economically feasible yields with a Benefit-Cost Ratio of 1.00 suggesting a potential for hemp cultivation in comparison to countries with established hemp industries. The present framework could be used to develop a pathway for adoption of hemp as a crop for the future in tropical countries.

The effect of forest area change in tropical islands towards baseflow and streamflow

Baseflow is a very important component in maintaining river flow. Baseflow is generated from groundwater flow. Baseflow is very important role in water conservation. Indonesia is located in a tropical climate. Based on the Koppen climate classification, Indonesia is included in the tropical rainforest climate (type Af), so that the characteristics of the climate, soil, flora and fauna are unique. About 70% of Indonesia’s territory consists of water. Baseflow in the tropical island region has a unique characteristic. This research aimed to obtain the knowledge on the effect of forest area change in tropical islands towards the characteristics of baseflow and streamflow that involved RDF filter parameter calibration, baseflow contribution towards streamflow based on the Baseflow Index (BFI) and Q90 on Q50 ratio, rain contribution on the total baseflow, baseflow stream domination, and discharge stability of streamflow. This research was conducted in three sub watersheds with forest area percentage of ±18% Bango Sub watershed, ±23% Brantas Hulu Sub watershed, and ±59% Cobanrondo Sub watershed. The results showed that One Parameter Algorhitm method satisfied the application of baseflow separation. There was a positive correlation between rain and baseflow. Baseflow dominated the streamflow in the research location. The greater the forest area, the more stable the flow condition from year to year.

Modelling of solar thermal energy for household use in equatorial latitude by using the F-Chart model

The Andean Equatorial Region, due to its geographic location, shows great potential for using solar energy. Solar thermal energy is of interest in the residential sector in Ecuador and other Andean countries as a method to avoid fossilderived fuels consumption. However, previous learnings of the operation of solar water heating systems in other latitudes cannot be used in the conditions of Ecuador. Thus, the performance of the solar thermal energy systems in this geographic region deserves further study that consider typical high levels of cloudiness and fast climate oscillations. The objective of this work was to investigate the effect of the orientation of solar thermal plates on their energy efficiency and model the behaviour of these systems to predict their operation under Equatorial Andean climate conditions. For the F-Chart calibration different slopes angles were used, according to the typical roofs slopes in Cuenca, Ecuador. Results showed a monthly solar fraction, contributed by an evacuated tube collector is 26% higher than the flat plate collectors. The results also depict that, in the conditions of Cuenca, the greater solar water heating occurs when the collector is inclined 14° and facing towards the south. These findings can be used to predict the best operational conditions for using solar thermal energy collectors to produce hot water in the residential sector under equatorial highland altitude conditions.

Variables of influence on thermal performance of buildings under transient conditions

Residential buildings significantly increase electricity demand, especially in developing countries. In this case, the requirements addressed by the standards can ensure the climatic adequacy of the envelope, enhance thermal performance, and promote thermal comfort conditions while reducing energy consumption. However, the criteria for evaluating the thermal performance of a building’s envelope that is commonly adopted in energy performance standards and codes have proved to be inefficient in hot climates. The heat exchanges within buildings are dependent on solar radiation and ventilation. The purpose of this article is to establish the variables with the greatest influence on the thermal performance of naturally ventilated dwellings in hot climates (equatorial, tropical and subtropical). For this investigation, a factorial design was adopted for sensitivity analysis. The structure of the factorial experiment defined the simulations of four patterns of single-family and multifamily residential buildings. We varied the thermophysical properties of the external walls and roofs, the heat gain coefficient of the openings, and natural ventilation. Brazil was adopted as a basis for climate analysis, including equatorial, tropical and subtropical climates. The analyses were based on comfort hours in an adaptive model and statistically evaluated using Analysis of Variance (ANOVA) tests. In general, the absorption of the walls and cover, the thermal transmittance of the cover and the natural ventilation were the variables of greatest influence on thermal comfort in a hot climate.

Weathering profiles developed on gneisses from Batchenga and Doua areas, central Cameroon: Climate and topography controls

Two weathering profiles from Batchenga and Doua areas in Central Cameroun developed under contrasting equatorial climate conditions and located in different morphological units have been selected to constraint the variability of their morphology, mineralogy, and geochemistry. The parent rock is a biotite and amphibole gneiss with a heterogranular granoblastic texture. The weathering profiles are typical lateritic materials formed in a humid tropical climate zone. They comprise, from bottom to top, coarse saprolite, fine saprolite, nodular horizon and loose clayey horizon. The Doua weathered materials are more clay-rich as a result of intense chemical weathering (CIA: 95.0–99.5%) than those of Batchenga (CIA: 51.3–87.8%). The weathering profile of Doua is thicker (12.00 m) than that of Batchenga (6.30 m). The intense chemical weathering and the total leaching of mobile elements as a consequence of good drainage led to the formation of a hard nodular horizon in the Doua weathering profile. The mineral composition is dominated by quartz, kaolinite, muscovite, illite, hematite/goethite, gibbsite and anatase. Illite is particularly abundant in the Batchenga weathering profile. Among trace elements, Ba, V, Zr, Sr, and Cr have high contents while REE show moderate contents with the highest contents in the Batchenga weathering profile. The oxidizing conditions favor positive Ce anomalies while positive Eu anomalies are due to the resistance of Eu mineral bearers. Geochemical mass balance results suggest that climate and topographic position which influence the quality of drainage greatly influence the distribution patterns of major, trace and rare earth elements in the weathering profiles. Apart from Al, Fe, and P, major elements have been much leached than trace elements during chemical weathering. Thus, the important variations are explained by the variation in the annual rainfall and topographic conditions.

MODIS high-resolution MAIAC aerosol product: Global validation and analysis

This paper attempt to verify the accuracy of the Multi-Angle Implementation of Atmospheric Correction (MAIAC) aerosol optical depth (AOD) product on a global scale using AOD measurements during 2000–2019 at 332 Aerosol Robotic Network (AERONET) sites. The results indicate that MAIAC AOD retrievals are highly correlated with ground-based AOD measurements. The correlation coefficients (R) are greater than 0.8 at more than 68% of AERONET sites. Meanwhile, the performance of MAIAC AOD retrievals in different climate zones is also investigated. The accuracy of MAIAC AOD retrievals is high (within expected error (EE) = 87.49% and 83.15%) in the regions of tropical rainforest climate and tropical open forest climate. Then, the uncertainties and estimation deviation of MAIAC AOD retrievals in various land-cover-types are analyzed. The results find that the MAIAC AOD retrievals show high correlation with aerosol measurements in the forest (within EE > 95%), while the poor accuracy is always observed in the barren areas (within EE = 62.56%, RMSE = 0.12). The uncertainty of the MAIAC AOD retrievals is not only related to the satellite and solar geometries, but also depends on the aerosol conditions, which become larger with the increase of aerosol loading and Ångstrom exponent (AE). Finally, the spatial variations of AOD values over the world are investigated. High AOD values are mainly distributed in Central Africa, Saudi Arabia, Southern Asia and China.

Case Study Comparing Effects of Microplastic Derived from Bottle Caps Collected in Two Cities on Triticum aestivum (Wheat)

As plastic has become an integral component of daily life, microplastic has become a ubiquitous, unavoidable constituent of nearly all ecosystems. Besides monitoring the amount and distribution of microplastic in the environment, it is necessary to understand the possible direct effects, especially toxicity and how it is affected by environmental factors where it is discarded. The present study investigated how microplastic derived from high-density polyethylene bottle caps collected in two climatically different cities, i.e., Singapore (tropical rainforest climate) and Lahti, Finland (continental climate), affected the essential agricultural grain crop, Triticum aestivum (L.). Wheat seedlings were exposed to microplastic derived from these collected bottle caps, as well as new and artificially aged caps, for seven days. Morphological parameters, such as root and shoot length and oxidative stress development, were measured. Exposure to microplastic derived from the caps resulted in reduced seedling root and shoot lengths compared to the controls, as well as enhanced lipid peroxidation and catalase activity. With all parameters tested, microplastic derived from Lahti bottle caps exhibited more severe effects than Singapore, which was similar to that elicited by new microplastic. The Singapore microplastic had possibly leached its toxic substances before collection due to accelerated degradation promoted by the prevailing warmer climate conditions.

Impacts of droughts and floods on croplands and crop production in Southeast Asia – An application of Google Earth Engine

While droughts and floods have intensified in recent years, only a handful of studies have assessed their impacts on croplands and production in Southeast Asia. Here, we used the Google Earth Engine to assess the droughts and floods and their impacts on croplands and crop production over 40 years from 1980 to 2019. Using the Palmer Drought Severity Index (PDSI) as the basis for determining the drought and flood levels, and crop damage levels, crop production loss in both the Monsoon Climate Region (MCR) and the Equatorial Climate Region (ECR) of Southeast Asia was assessed over 47,192 grid points with 10 × 10-kilometer resolution. We found that rainfed crops were severely affected by droughts in the MCR and floods in the ECR. About 9.42 million ha and 3.72 million ha of cropland was damaged by droughts and floods, respectively. We estimated a total loss of 20.64 million tons of crop production between 2015 and 2019. Rainfed crops in Thailand, Cambodia, and Myanmar were strongly affected by droughts, whereas Indonesia, the Philippines, and Malaysia were more affected by floods over the same period. Accordingly, four levels of policy interventions were prioritized by considering the geolocated crop damage levels.

ESTIMATING FINE DEAD FUEL MOISTURE CONTENT UNDER EQUATORIAL CLIMATE CONDITIONS

The measurement of the fine dead fuel moisture content (FDFMC) is extremely important for forest fire prevention and suppression activities, as it has a great influence on the ignition probability and fire behavior. The Fine Fuel Moisture Code (FFMC) from the Fire Weather Index (FWI), is one of the most used models to estimate the FDFMC. Nevertheless, studies that assess the efficiency of this model in Brazil or in low latitude regions are rare. The present study aimed to evaluate the efficiency of the FFMC in an equatorial climate area and to develop a new model capable of estimating the FDFMC with greater precision. For this purpose, 861 random samples of fine dead fuel had their moisture content determined through oven drying. The obtained values were compared with those estimated by the FFMC and correlated with meteorological parameters to build a regression model. The results obtained show that the FDFMC was overestimated by the FFMC. The independent variables with the greatest influence on the FDFMC were, in decreasing order of significance: air relative humidity, air temperature, amount of rainfall in the last 24 hours and number of days without rainfall. The developed model presented good statistical parameters (r2 = 0.86; p <0.0001; RMSE = 0.22) and can be used, in areas with similar characteristics of the study area, to estimate the daily fire risk and to determine ideal conditions for prescribed burns.

ENSO phase-locking biases from the CMIP5 to CMIP6 models and a possible explanation

The El Niño-Southern Oscillation (ENSO) system is the most significant equatorial interannual climate variability pattern and has enormous global climate impacts. The ability to forecast ENSO accurately is crucially important to human livelihoods worldwide. ENSO is characterized by strong winter-peaking sea surface temperature (SST) anomalies in the central-eastern tropical Pacific during the mature phase. However, the bias in simulating ENSO phase-locking behavior persists in climate models. In this study, the ENSO seasonal phase-locking behaviors simulated in 42 Coupled Model Intercomparison Project Phase 6 (CMIP6) models are evaluated by comparing 43 CMIP5 models and observations. Only a few models (12 CMIP5 and 15 CMIP6) simulated ENSO with a majority proportion of winter-peaking events, which indicates that reasonable ENSO seasonal phase-locking is still a challenge for state-of-the-art climate models. Furthermore, the seasonal cycle of the zonal SST gradient along the equator can explain approximately 24% and 27% of the variance in the ENSO phase-locking for CMIP5 and CMIP6, respectively. In particular, the strengths of the zonal SST gradient in the central-eastern Pacific during boreal spring and autumn are crucial. The biases in simulating the seasonal changes in the zonal SST gradient influence the zonal advective feedback's strengths that respond to the anomalous SST of ENSO, therefore disturbing the simulation of ENSO phase-locking. Improvement of the simulated ENSO phase-locking should be realized by focusing on the zonal SST gradient's seasonal cycle.

Classification of Malaysian Architecture Revisited

This paper attempts to portray the classification of Malaysian architecture according to the trends and changes along with the advancement of the economy, technology and growth of architecture schools in Malaysia. The faces of Malaysian architecture are very much influenced by graduates in architecture returning from overseas and the establishment of the Malaysian Institute of Architects. Malaysia is blessed with natural beauty and resources that enable it to be independent. The hot-wet equatorial climate of Malaysia and its high humidity together with the abundance of timber and other cheap building materials enable builders and architects alike to experiment with the built forms. The traditional and vernacular architecture that has been crystallized in the colonial style by the pioneer British architects who designed the government quarters and other government buildings in Malaysia revealed the attention towards the climatic factors and the style that later developed into modern and post-modern style that appear in the residential design of the Malaysian landscape today. This paper employs an exploratory technique from earlier writings and longitudinal historical evidences of Malaysian architecture, visual surveys from the digital media and verbal comments from the practising Architects interviewed. The finding shows that the Malaysian Architecture can be classified according to era, style and contemporary trends influenced by the changes in the world.

Comfortable Liveable Space: Shipping Container and Bamboo as Sustainable Building Materials in Equatorial Climate Perspective?

The development of liveable space made from shipping containers becomes a trend even in Malaysia with the hot and humid climate persisting throughout the year. For sustaining the indoor comfort, building insulation is well adapted to increase thermal resistance and reduce the dependency on the mechanical cooling systems. The prospective of a shipping container as an efficient construction material and bamboo as a sustainable insulation material is well documented but basic information on the internal environment that has an impact on a person, particularly risk potential towards sick building syndrome (SBS) has been absent. Therefore, the measurements of both indoor and outdoor temperatures, relative humidity and CO2 concentration with two different conditions were done by using different sets of data loggers for at least 70 days under each condition. The first condition is a bare unit of the shipping container and followed by the installation of untreated bamboo as insulation for the second condition. This research reveals that high temperatures were recorded up to 40°C in both conditions and untreated bamboo as insulation increased the relative humidity levels up to the maximum, 100%. The mean values of CO2 concentration are in the range of 1,869 ppm to 2,938 ppm and they reach up to 5,000 ppm at the most of the intervals, indicating a significant contribution to SBS. The condition of the equatorial climate denies the compatibility of the shipping container to be used as the building material of liveable space. The quality and treatment of the bamboo must be the ultimate priority

Effect of Phase Change Materials on the Thermal Performance of Residential Building Located in Different Cities of a Tropical Rainforest Climate Zone

This study aims to investigate the thermal performance of PCM and PCM combined with nighttime natural (NV) and mechanical ventilation (MV) applied to a residential building located in eight cities of tropical rainforest climate zone (Af). The analysis was accomplished using numerical simulations and developing a unique methodology for selecting the PCM melting temperature based on the thermal comfort limits. The thermal performance of the PCM integrated building was quantitatively evaluated using the concept of peak temperature drop. Additionally, a novel indicator of Total Temperature Drop (TTD) was introduced to determine the overall impact of the PCM and PCM combined with NV/MV on the thermal comfort conditions inside the building. The results showed that PCM 28 was the most efficient in improving the thermal performance of the building located in the Af climate zone, achieving a TTD of up to 356 °C per year. The usage of PCM 28 combined with nighttime natural ventilation improved the TTD values by up to 15%, whereas the integration of PCM 28 combined with mechanical ventilation resulted in a TTD values increase of up to 45%. Conclusively, mechanical ventilation showed its superiority over natural ventilation in the tropical rainforest climate, and PCM 28 applied together with mechanical ventilation could be used as the optimum combination for the whole climate zone.