Lagged temperature effect with mosquito transmission potential explains dengue variability in southern Taiwan: Insights from a statistical analysis

The purpose of this study was to link meteorological factors and mosquito (Aedes aegypti) abundance to examine the potential effects of climate variations on patterns of dengue epidemiology in Taiwan during 2001-2008. Spearman's rank correlation tests with and without time-lag were performed to investigate the overall correlation between dengue incidence rates and meteorological variables (i.e., minimum, mean, and maximum temperatures, relative humidity (RH), and rainfall) and percentage Breteau index (BI) level > 2 in Taipei and Kaohsiung of northern and southern Taiwan, respectively. A Poisson regression analysis was performed by using a generalized estimating equations (GEE) approach. The most parsimonious model was selected based on the quasi-likelihood based information criterion (QICu). Spearman's rank correlation tests revealed marginally positive trends in the weekly mean (ρ = 0.28, p < 0.0001), maximum (ρ = 0.26, p < 0.0001), and minimum (ρ = 0.30, p < 0.0001) temperatures in Taipei. However, in Kaohsiung, all negative trends were found in the weekly mean (ρ = − 0.32, p < 0.0001), maximum (ρ = − 0.30, p < 0.0001), and minimum (ρ = − 0.32, p < 0.0001) temperatures. This study concluded that based on the GEE approach, rainfall, minimum temperature, and RH, all with 3-month lag, and 1-month lag of percentage BI level > 2 are the significant predictors of dengue incidence in Kaohsiung (QICu = − 277.77). This study suggested that warmer temperature with 3-month lag, elevated humidity with high mosquito density increased the transmission rate of human dengue fever infection in southern Taiwan.     

Climate variations and Salmonella infection in Australian subtropical and tropical regions

This study aims to quantify the relationship between climate variations and cases of Salmonella infection in subtropical and tropical areas in Australia. Brisbane in a subtropical area and Townsville in a tropical area of Queensland were selected as the study regions. Local meteorological variables and notified cases of Salmonella infection from January 1990 to July 2005 were provided by local authorities. Spearman correlation and time-series adjusted Poisson regression were applied controlling for autoregression, lag effects, seasonal variation and long-term trend. Natural cubic spline and Hockey Stick model were used to estimate a potential threshold temperature. Spearman correlation indicated that maximum and minimum temperatures, relative humidity at 9 am and 3 pm, and rainfall were all positively correlated with the number of cases in both Brisbane and Townsville, with the lag values of the effects up to 2 weeks in Brisbane and 2 months in Townsville. Only temperature and rainfall were significantly included in the regression models in both regions. The models suggested that a potential 1 °C rise in maximum or minimum temperature may cause a very similar increase in the number of cases in the two regions. No threshold for the effect of maximum or minimum temperature on Salmonella infection was detected in either region. The association between climate variations and Salmonella infection could be very similar in subtropical and tropical regions in Australia. Temperature and rainfall may be used as key meteorological predictors for the number of cases in both regions.     

Assessing the spatio-temporal climate variability in semi-arid Karamoja sub-region in north-eastern Uganda

Semi-arid areas show climatic variability on a spatio-temporal scale. There are few studies on the long-term trends and intensity of this variability from East Africa. We used National Ocean and Atmospheric Administration re-analysis climate data (1979–2009) in this study. Rainfall exhibited a non-significant long-term trend. The climate of the area is variable (coefficient of variation-CV?>35.0%) with spatio-temporal oddities in rainfall and temperature. A rise in minimum (0.9?°C), maximum (1.6?°C) and mean (1.3?°C) temperature occurred between 1979 and 2009. There were more months with climate variability indices below the threshold (<1.0) from 1979 to 1994 than between 1995 and 2009, with wetness intensity increasingly common after 2000, leading to the observed reduction in the recurrence of multi-year drought events. More extreme wet events (rainfall variability index?>2.6) were experienced between 2004 and 2009 than between 1984 and 2003. We consider that the use of spatio-temporal climatic information for timely adjustment to extreme climate variability events is essential in semi-arid areas.     

Effects of climate change on the wash-off of volatile organic compounds from urban roads

The predicted changes in rainfall characteristics due to climate change could adversely affect stormwater quality in highly urbanised coastal areas throughout the world. This in turn will exert a significant influence on the discharge of pollutants to estuarine and marine waters. Hence, an in-depth analysis of the effects of such changes on the wash-off of volatile organic compounds (VOCs) from urban roads in the Gold Coast region in Australia was undertaken. The rainfall characteristics were simulated using a rainfall simulator. Principal Component Analysis (PCA) and Multicriteria Decision tools such as PROMETHEE and GAIA were employed to understand the VOC wash-off under climate change. It was found that low, low to moderate and high rain events due to climate change will affect the wash-off of toluene, ethylbenzene, meta-xylene, para-xylene and ortho-xylene from urban roads in Gold Coast. Total organic carbon (TOC) was identified as predominant carrier of toluene, meta-xylene and para-xylene in < 1 μm to 150 μm fractions and for ethylbenzene in 150 μm to > 300 μm fractions under such dominant rain events due to climate change. However, ortho-xylene did not show such affinity towards either TOC or TSS (total suspended solids) under the simulated climatic conditions.     

Determination of bioclimatic comfort in Erzurum–Rize expressway corridor using GIS

In this study, topographical and climatical conditions are prescinded all along Erzurum–Rize expressway corridors to appoint the areas which have bioclimatic comfort in summer season (June, July, August). For this purpose, the climate data (temperature, relative humidity, wind speed) from nine different stations was entered in the digital data base. By dint of ArcGIS 9.1 software, climatic data were analysed and numerological maps were produced by Inverse Distance Weighted (IDW) interpolation method. As a method, bioclimatically comfortable areas consists of: relative humidity between 30 and 65%, temperature between 15 and 20 °C, and wind speed up to 5 m/s. The maps were scored as 0 for uncomfortable and 1 for comfortable and superposed, and bioclimatic comfort area (temperature: 1–relative humidity: 1–wind speed: 1) were determined. Besides, topographic factors were appreciated. As a result of this study, it is concerned that the area (452749 ha. % 63); beginning from south of the Mountains Mescit which is started by Black Sea coastline to Mountain Mescit (3230 m) is out of bioclimatic comfort region; the Erzurum depression (1758 m) beginning from the Mountains Mescit has been determined that area has bioclimatic comfort conditions. As a consequence, it is confirmed that one of the ideal area which has bioclimatic comfort is the Erzurum depression area in Turkey.     

Global and regional analysis of climate and human drivers of wildfire

Identifying and quantifying the statistical relationships between climate and anthropogenic drivers of fire is important for global biophysical modelling of wildfire and other Earth system processes. This study used regression tree and random forest analysis on global data for various climatic and human variables to establish their relative importance. The main interactions found at the global scale also apply regionally: greatest wildfire burned area is associated with high temperature (> 28 °C), intermediate annual rainfall (350-1100 mm), and prolonged dry periods (which varies by region). However, the regions of highest fire incidence do not show clear and systematic behaviour. Thresholds seen in the regression tree split conditions vary, as do the interplay between climatic and anthropogenic variables, so challenges remain in developing robust predictive insight for the most wildfire-threatened regions.Anthropogenic activities alter the spatial extent of wildfires. Gross domestic product (GDP) density is the most important human predictor variable at the regional scale, and burned area is always greater when GDP density is minimised. South America is identified as a region of concern, as anthropogenic factors (notably land conversions) outweigh climatic drivers of wildfire burned area.     

Modeling the thermal performance of an aquaculture pond heating with greenhouse

A transient analytical model is presented to study the effectiveness of an even shape greenhouse used for heating the aquaculture pond during extreme winters. The model was solved for the climatic conditions of Delhi (Latitude: 28°35′N), representing the northern India (comprising the states of Haryana, Punjab, Uttarakhand and Himachal Padesh) for the typical day (20th January) of winter. A simple trapezoidal design of aquaculture pond is proposed. Parametric studies involved the effects of length, breadth, depth, inclination of lining of fishpond, depth of water and air change in the greenhouse on the water heating in the fishpond. The performance of fishpond was assessed in terms of temperature gain, mean thermal efficiency and thermal load leveling. The optimum parameters for fishpond were 30 m length, 16 m breadth, 1.25 m depth, 1.0 m water depth, 75° lining inclination, and 8 air changes per hour for maximum temperature gain, maximum thermal efficiency and minimum thermal load leveling. A 20 °C rise in water temperature could be achieved during the day and 11 °C in the month of January. The maximum heat gain and loss are at around 16:00 and 7:00 h of the days, respectively.     

Outdoor measurements and temperature comparisons of seven monitoring stations: Preliminary studies in Curitiba,Brazil

Urbanization brings several changes to the natural environment. First, vegetation is supressed and natural scenery is modified, in order to accommodate manmade buildings and streets. Consequences bring a direct effect on fauna and flora and, due to a modified environment, with heat fluxes having a different pattern from that of the original site, on climatic features, such as on air temperature and humidity, radiative and convective heat exchanges. Thus, one of the factors that can contribute directly to the creation of urban climate is land use. The present study investigates how land use influences local temperatures in Curitiba, Brazil (25°31′S, 917 m elevation). For that purpose, seven different locations of the city were analyzed during a 1-month period by monitoring air temperature and humidity. Also, land use patterns around each location were quantified, according to five different categories established for that purpose: water area, built area, free area, paved area and green area. The monitoring of climatic data occurred in winter (June/July) of 2002. Comparisons were made regarding averages of the minimum, average and maximum temperatures for each location, qualitatively and quantitatively. As a final step of this study, formulas were developed expressing the local temperatures as a function of air temperatures, solar radiation and the wind speed of the meteorological station, which was used as reference station.     

High temperature effects on out-patient visits and hospital admissions in Chiang Mai, Thailand

Objectives

This study investigated the short-term effects of temperature on out-patient visits and hospital admissions in Chiang Mai, Thailand. While mortality outcomes in the literature have been reported, there is less evidence of morbidity effects with very few studies conducted in developing countries with subtropical or tropical climate.

Methods

Time-series regression analysis was employed using generalized negative binomial regression to model the short-term relationships between temperature and morbidity after controlling for seasonal patterns and other potential confounders. Lag effects up to 13 days and effect modification by age (0-14 years, 15-64 years, ≥ 65 years) were examined.

Results

Temperature effects with wide confidence intervals were found, with an increase in diabetic visits of 26.3% (95% CI: 7.1%-49.0%), and circulatory visits of 19.2% (95% CI: 7.0%-32.8%) per 1 °C increase in temperature above an identified threshold of 29 °C. Additionally, there was a rise of both visits (3.7% increase, 95% CI: 1.5%-5.9%) and admissions (5.8% increase, 95% CI: 2.3%-9.3%) due to intestinal infectious disease in association with each 1 °C increase across the whole temperature range. The effects of temperature were stronger in the elderly though not statistically significant.

Conclusions

Daily morbidity in Chiang Mai was positively associated with temperature with a lag effect of up to 2 weeks, which was longer than lag effects previously reported. Public health preparedness and interventions should be considered to minimise possible increased hospital visits and admissions during hot weather.     

Quantification of climate change effects on extreme precipitation used for high resolution hydrologic design

Design of urban drainage structures should include the climatic changes anticipated over the technical lifetime of the system. In Northern Europe climate changes implies increasing occurrences of extreme rainfall. Three approaches to quantify the impact of climate changes on extreme rainfall are studied, all based on output from historical rain series of the present climate and output from Regional Climate Models. Two models are applied, one being based on an extreme value model, the Partial Duration Series Approach, and the other based on a stochastic rainfall generator model. Finally an approach is based on identification of areas, where the present climate resembles the anticipated future climate for the region in question. The results indicate that design intensities in Denmark are likely to be increased by 10–50% within the next 100 years. The increase in design intensities depend on the duration and the return period in question.     

Thermal and health outcomes of energy efficiency retrofits of homes of older adults

Mitigation of thermal stress and adverse indoor climatic conditions is important to older low‐income populations whose age, health, and economic circumstances make them vulnerable to indoor environmental conditions. This research examines whether energy retrofits in affordable housing for older adults can also improve indoor climatic (i.e., temperature, humidity, air infiltration) conditions and whether such improvements correspond with improved health and comfort of residents. An apartment complex for low‐income older adults in Phoenix was the study site. In 2010, renovations were undertaken to make it more energy efficient and to replace interior cabinetry, flooring, and paint with materials that had low or no volatile organic compounds (VOCs). Fifty‐seven residents from 53 apartment units participated in both baseline (pre‐renovation) and 1 year post‐renovation data collection trials. Environmental measures included temperature, relative humidity, and air infiltration. Health measures included general health, emotional distress, and sleep. Four questions addressed residents' perceptions of temperature quality. Results demonstrated a 19% reduction in energy consumption following the retrofit. In addition, fixed effects statistical models of the panel data showed significant stabilization of unit temperature from pre‐retrofit to 1 year post‐retrofit. Reductions in an apartment's temperature extremes of 27.2°C (81°F) and above also corresponded with improvement in occupant's reported health over the same time period, although not with occupant's perceptions of thermal comfort.     

Changing climate and endangered high mountain ecosystems in Colombia

High mountain ecosystems are among the most sensitive environments to changes in climatic conditions occurring on global, regional and local scales. The article describes the changing conditions observed over recent years in the high mountain basin of the Claro River, on the west flank of the Colombian Andean Central mountain range. Local ground truth data gathered at 4150 m, regional data available at nearby weather stations, and satellite info were used to analyze changes in the mean and the variance, and significant trends in climatic time series. Records included minimum, mean and maximum temperatures, relative humidity, rainfall, sunshine, and cloud characteristics. In high levels, minimum and maximum temperatures during the coldest days increased at a rate of about 0.6 degrees C/decade, whereas maximum temperatures during the warmest days increased at a rate of about 1.3 degrees C/decade. Rates of increase in maximum, mean and minimum diurnal temperature range reached 0.6, 0.7, and 0.5 degrees C/decade. Maximum, mean and minimum relative humidity records showed reductions of about 1.8, 3.9 and 6.6%/decade. The total number of sunny days per month increased in almost 2.1 days. The headwaters exhibited no changes in rainfall totals, but evidenced an increased occurrence of unusually heavy rainfall events. Reductions in the amount of all cloud types over the area reached 1.9%/decade. In low levels changes in mean monthly temperatures and monthly rainfall totals exceeded + 0.2 degrees C and - 4% per decade, respectively. These striking changes might have contributed to the retreat of glacier icecaps and to the disappearance of high altitude water bodies, as well as to the occurrence and rapid spread of natural and man-induced forest fires. Significant reductions in water supply, important disruptions of the integrity of high mountain ecosystems, and dramatic losses of biodiversity are now a steady menu of the severe climatic conditions experienced by these fragile tropical environments.     

Impact of wind-driven rain on historic brick wall buildings in a moderately cold and humid climate: Numerical analyses of mould growth risk, indoor climate and energy consumption

This paper gives an onset to whole building hygrothermal modelling in which the interaction between interior and exterior climates via building enclosures is simulated under a moderately cold and humid climate. The focus is particularly on the impact of wind-driven rain (WDR) on the hygrothermal response, mould growth at interior wall surfaces, indoor climate and energy consumption. First the WDR load on the facades of a 4 m × 4 m × 10 m tower is determined. Then the hygrothermal behaviour of the brick walls is analysed on a horizontal slice through the tower. The simulations demonstrate that the impact of WDR loads on the moisture contents in the walls is much larger near the edges of the walls than at the centre. The obtained relative humidity and temperature at the interior wall surfaces are combined with isopleths of generalised spore germination time of fungus mould. The results show that WDR loads can have a significant impact on mould growth especially at the edges of the walls. Finally, for the case analysed, the WDR load causes a significant increase of indoor relative humidity and energy consumption for heating.     

Assessment of the thermal environment effects on human comfort and health for the development of novel air conditioning system in tropical regions

This research shows the result of a brainstorming by medical experts in the first ranking university medical school and hospital of Thailand. It was based on Delphi technique. The objective of this research was to study both direct and indirect effects of humidity and temperature on human health in air-conditioned buildings in Thailand. Afterwards, the result was used to design and develop split type air conditioner (conventional air conditioner) which could control relative humidity and temperature with precision air conditioning system to comply with the climate and the suitability of the people living in Thailand building. The result of operation with precision inverter air conditioning system showed that the temperature inside the room changed from the default value around ±0.2 °C (Case 1) and around ±0.35 °C (Case 2) and it could control relative humidity as a desired condition between 50-60% (both cases) which was the appropriate range for Thai climate. Moreover, energy consumption of precision inverter air conditioning system was still less than conventional air conditioning system for about 7.5%. This research could provide people living in Thailand air conditioned building with human thermal comfort and health.     

The effect of precipitation and air temperature on land‐cover change in the Sahel

Vegetation changes in the Sahel region are strongly affected by variation in rainfall, but air temperature has been considered a relatively minor climatic factor in previous studies. However, soil moisture, the major water source for vegetation in arid and semiarid regions, is generally dependent on temperature‐controlled evaporation. Therefore, we can hypothesize that air temperature modifies the sensitivity of vegetation greenness to rainfall because water loss in soil is critically vulnerable to temperature, although Sahel plants can tolerate high temperatures. In this study, the annual mean of daily maximum air temperature was used as a constraint in analyzing the relationships between annual changes in the cumulative enhanced vegetation index (EVI) and total rainfall. We found that rainfall increase in hotter years could not well induce land greening, and decreased rainfall in cooler years did not necessarily cause vegetation degradation. This presents the importance of temperature as a climatic component in understanding the mechanism of rainfall‐induced land‐cover changes in the Sahel region.     

Estimation of soil temperature profile in Hong Kong from climatic variables

A correlation study of the ground temperatures up to a soil depth of 3 m (for lawn condition) with the weather parameters has been performed making use of the observed data in the 4-year period 2006-2009. It is found that within the soil depth of 3 m, which belongs to the surface and shallow zones, the ground temperature is strongly correlated to the dry bulb air temperature whereas its dependence on the relative humidity, rainfall, global solar radiation or wind speed is weak. A multivariable nonlinear regression model was then developed based on the soil temperature and weather data within the same four-year period. This model can be utilized to predict soil temperature at various depths underground. The required inputs of the model are the day number of the year, soil depth and dry bulb air temperature. The model has been validated by the data records of the same site in the previous years, as well as the data record from another site in more recent years. This regression model provides a simple, fast and accurate alternative method for the estimation of natural ground temperature.     

The effect of air-conditioning parameters and deposition dust on microbial growth in supply air ducts

To investigate the effect of air-conditioning parameters (including temperature, relative humidity and air velocity) and deposition dust on microbial growth in supply air duct, a complete test facility according to ASHRAE Standard 62.1-2007 was constructed. A series of experiments for testing microbial concentration (including bacteria and fungus) were conducted under different working conditions (such as different temperatures and relative humidity). The air velocity was constantly kept at 2.0 m/s. Orthogonal design was employed for the analysis of test data. The results indicated that air velocity attenuation down the direction of the supply air affected dust distribution at the bottom of duct, to some extent, and the number of microorganisms was positively correlated with the quantity of dust. In the range of temperature 22-32 °C and relative humidity (RH) 40-90%, microbial growth significantly accelerated with higher temperature and RH increasing. The organic compounds composing the dust also had great impact on microbial growth. The basic researches are contributed to control the growth of microorganism and improve the indoor microenvironment in the air-conditioning room.     

A new approach to regenerating heat and moisture in ventilation systems

For countries with a cold climate the large difference (30–60 °C) in winter between indoor and outdoor temperatures leads to (a) large heat losses in ventilation systems; (b) moisture freezing at the systems exit; (c) great reduction in the indoor humidity. Here we present a new approach for regenerating heat and moisture in ventilation systems in cold climates which allows resolution of these problems. The method has been tested under climatic conditions of West Siberia (winter 2005–2006). The prototype system requires very little maintenance, has a low capital cost, is compact and energy efficient. Technical, economic and social aspects of this method are discussed.     

Impacts of day versus night warming on soil microclimate: Results from a semiarid temperate steppe

One feature of climate warming is that increases in daily minimum temperature are greater than those in daily maximum temperature. Changes in soil microclimate in response to the asymmetrically diurnal warming scenarios can help to explain responses of ecosystem processes. In the present study, we examined the impacts of day, night, and continuous warming on soil microclimate in a temperate steppe in northern China. Our results showed that day, night, and continuous warming (approximately 13 W m^− 2 with constant power mode) significantly increased daily mean soil temperature at 10 cm depth by 0.71, 0.78, and 1.71 °C, respectively. Night warming caused greater increases in nighttime mean and daily minimum soil temperatures (0.74 and 0.99 °C) than day warming did (0.60 and 0.66 °C). However, there were no differences in the increases in daytime mean and daily maximum soil temperature between day (0.81 and 1.13 °C) and night (0.81 and 1.10 °C) warming. The differential effects of day and night warming on soil temperature varied with environmental factors, including photosynthetic active radiation, vapor-pressure deficit, and wind speed. When compared with the effect of continuous warming on soil temperature, the summed effects of day and night warming were lower during daytime, but greater at night, thus leading to equality at daily scale. Mean volumetric soil moisture at the depth of 0-40 cm significantly decreased under continuous warming in both 2006 (1.44 V/V%) and 2007 (0.76 V/V%). Day warming significantly reduced volumetric soil moisture only in 2006, whereas night warming had no effect on volumetric soil moisture in both 2006 and 2007. Given the different diurnal warming patterns and variability of environmental factors among ecosystems, these results highlight the importance of incorporating the differential impacts of day and night warming on soil microclimate into the predictions of terrestrial ecosystem responses to climate warming.     

Experimental research on physiological index at the heat tolerance limits in China

In this study, the heat stress and heat tolerance of 148 male volunteers were examined under different climatic conditions in a stainless steel climatic chamber. The conditions were 30 to 42° dry bulb temperature and 40 to 80 percent relative humidity. The subjects, aged from 19 to 26 years old, performed various activities at the metabolic heat of 175, 349 and 580 W, respectively. The exposure durations and resulting heat stress were determined by measuring oral temperature, skin temperature, heart rates, blood pressure and sweating responses. The study proposed physiological limit values at exposure limits. Moreover, the study suggested that physiological measures from the experiments should be applied to evaluate the classification of extreme heat working environments in China.