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1.
Environ Res ; 216(Pt 3): 114666, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36328225

RESUMEN

This study analyzed the association between heatstroke incidence and daily maximum wet bulb globe temperature (WBGT) for all 47 prefectures in Japan by age group and severity using time-series analysis, controlling for confounders, such as seasonality and long-term trends. With the obtained association, the relative risk between the reference WBGT (defined as the value at which heatstroke starts to increase) and the daily maximum WBGT at 30 °C (RRwbgt30) of each prefecture were calculated. For the heatstroke data, the daily number of heatstroke patients transported by ambulance at the prefecture level, provided by the Fire and Disaster Management Agency, was utilized. The analysis was conducted for age groups of 7-17 y, 18-64 y, and ≥65 y, and for severity of Deceased, Severe, Moderate (combined as DSM), and Mild. The analysis period was set from May 1 to September 30, 2015-2019. Finally, the correlation between RRwbgt30 and the average daily maximum WBGT during the analysis period (aveWBGTms) of each prefecture was analyzed to examine the regionality of heatstroke incidence. The result showed that RRwbgt30 is negatively correlated with aveWBGTms for the age group 18-64 y and ≥65 y (except for the age group 7-17 y) and for severity. The natural logarithm of the RRwbgt30 of all 47 prefectures ranged from 2.0 to 8.2 for the age group 7-17 y, 1.1 to 4.0 for the age group 18-64 y, 1.8 to 6.0 for the age group ≥65 y, and 1.0 to 3.6 for DSM, and 0.9 to 4.0 for Mild. This regionality can be attributed to the effects of heat adaptation, where people in hotter regions are accustomed to implementing measures against hot environments and are more heat acclimatized than people in cooler regions.


Asunto(s)
Trastornos de Estrés por Calor , Golpe de Calor , Termotolerancia , Humanos , Temperatura , Ambulancias , Japón/epidemiología , Golpe de Calor/epidemiología , Golpe de Calor/etiología , Calor
2.
Environ Res ; 232: 116390, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37302741

RESUMEN

One of the negative consequences of increased air temperatures due to global warming is the associated increase in heat-related mortality and morbidity. Studies that focused on future predictions of heat-related morbidity do not consider the effect of long-term heat adaptation measures, nor do they use evidence-based methods. Therefore, this study aimed to predict the future heatstroke cases for all 47 prefectures of Japan, by considering long-term heat adaptation by translating current geographical differences in heat adaptation to future temporal heat adaptation. Predictions were conducted for age groups of 7-17, 18-64, and ≥65 years. The prediction period was set to a base period (1981-2000), mid-21st century (2031-2050), and the end of the 21st century (2081-2100). We found that the average heatstroke incidence (number of patients with heatstroke transported by ambulance per population) in Japan under five representative climate models and three greenhouse gas (GHG) emissions scenarios increased by 2.92- for 7-17 years, 3.66- for 18-64 years, and 3.26-fold for ≥65 years at the end of the 21st century without heat adaptation. The corresponding numbers were 1.57 for 7-17 years, 1.77 for 18-64 years, and 1.69 for ≥65 years with heat adaptation. Furthermore, the average number of patients with heatstroke transported by ambulance (NPHTA) under all climate models and GHG emissions scenarios increased by 1.02- for 7-17 years, 1.76- for 18-64 years, and 5.50-fold for ≥65 years at the end of 21st century without heat adaptation, where demographic changes were considered. The corresponding numbers were 0.55 for 7-17 years, 0.82 for 18-64 years, and 2.74 for ≥65 years with heat adaptation. The heatstroke incidence, as well as the NPHTA, substantially decreased when heat adaptation was considered. Our method could be applicable to other regions across the globe.


Asunto(s)
Gases de Efecto Invernadero , Golpe de Calor , Termotolerancia , Humanos , Anciano , Cambio Climático , Japón/epidemiología , Calor , Golpe de Calor/epidemiología , Golpe de Calor/etiología
3.
Environ Res ; 218: 114988, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36463996

RESUMEN

BACKGROUND: Climate change and its subsequent effects on temperature have raised global public health concerns. Although numerous epidemiological studies have shown the adverse health effects of temperature, the association remains unclear for children aged below five years old and those in tropical climate regions. METHODS: We conducted a two-stage time-stratified case-crossover study to examine the association between temperature and under-five mortality, spanning the period from 2014 to 2018 across all six regions in Malaysia. In the first stage, we estimated region-specific temperature-mortality associations using a conditional Poisson regression and distributed lag nonlinear models. We used a multivariate meta-regression model to pool the region-specific estimates and examine the potential role of local characteristics in the association, which includes geographical information, demographics, socioeconomic status, long-term temperature metrics, and healthcare access by region. RESULTS: Temperature in Malaysia ranged from 22 °C to 31 °C, with a mean of 27.6 °C. No clear seasonality was observed in under-five mortality. We found no strong evidence of the association between temperature and under-five mortality, with an "M-" shaped exposure-response curve. The minimum mortality temperature (MMT) was identified at 27.1 °C. Among several local characteristics, only education level and hospital bed rates reduced the residual heterogeneity in the association. However, effect modification by these variables were not significant. CONCLUSION: This study suggests a null association between temperature and under-five mortality in Malaysia, which has a tropical climate. The "M-" shaped pattern suggests that under-fives may be vulnerable to temperature changes, even with a small temperature change in reference to the MMT. However, the weak risks with a large uncertainty at extreme temperatures remained inconclusive. Potential roles of education level and hospital bed rate were statistically inconclusive.


Asunto(s)
Calor , Clima Tropical , Niño , Humanos , Preescolar , Temperatura , Estudios Cruzados , Clase Social , Cambio Climático , Mortalidad , Frío
4.
Yale J Biol Med ; 96(2): 189-196, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37396982

RESUMEN

Background: Relatively little attention has been paid to the potential effects of rising temperatures on changes in human behavior that lead to health and social consequences, including aggression. This study investigated the association between ambient temperature and aggression using assault death data from Seoul, South Korea (1991-2020). Methods: We conducted a time-stratified case-crossover analysis based on conditional logistic regression to control for relevant covariates. The exposure-response curve was explored, and stratified analyses were conducted by season and sociodemographic characteristics. Results: The overall risk of assault deaths significantly increased by 1.4% per 1°C increase in ambient temperature. A positive curvilinear relationship was observed between ambient temperature and assault deaths, which flattened out at 23.6°C during the warm season. Furthermore, risk increases were higher in males, teenagers, and those with the least education. Conclusion: This study highlighted the importance of understanding the impact of rising temperatures on aggression in the context of climate change and public health.


Asunto(s)
Agresión , Calor , Masculino , Adolescente , Humanos , Temperatura , Estaciones del Año , Exposición a Riesgos Ambientales
5.
J Environ Manage ; 299: 113550, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34438312

RESUMEN

Water quality monitoring programs have been widely implemented worldwide to monitor and assess water quality and to understand its trends. However, water quality analysis based on point-source field observations is difficult to perform at large spatial and temporal scales. In this paper, a fully automated Google Earth Engine (GEE) application algorithm was developed to estimate the total suspended solids (TSS) concentration in the Chesapeake Bay based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra imagery. Combining long-term archived satellite data (2002-2020) with field observations, the concentrations and spatiotemporal patterns of TSS in the bay water were evaluated. Time series analysis showed a statistically significant decreasing trend in TSS concentration between 2002 and 2020, suggesting that the sediment concentration in the bay has gradually been decreasing over the last two decades. The decreasing trend was observed in 49 out of 60 segments of the bay, implying that substantial progress has been made toward attaining the Chesapeake Bay water quality standards. Based on the monthly TSS analysis, 12 major peak events of TSS were identified in the Chesapeake Bay, which coincided with extreme winter blizzards and summer hurricane events. The GEE application and the results presented herein complement the existing monitoring program in attaining the water quality standards of the bay.


Asunto(s)
Tormentas Ciclónicas , Imágenes Satelitales , Bahías , Monitoreo del Ambiente , Calidad del Agua
6.
J Clin Biochem Nutr ; 67(3): 290-296, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33293770

RESUMEN

This study investigated the effects of a drink supplement containing Momordica charantia extract from bitter melon on physical fitness and levels of stress hormones during a four-week exercise training program in a hot environment. Ten male tennis players were orally administrated in a four-week (100 ml, 6 times a day), and the pre- and post-supplementation levels of different physical fitness variables and cortisol, and adrenocorticotropic hormone in plasma were measured at four time-points-before (baseline), during, and after the exercise, and on the next day of the supplementation. The findings showed that the supplementation has significant positive effects on enhancement of physical fitness parameters especially balance (d = 22.10, p = 0.013), flexibility (d = 4.83, p = 0.015), and cardiorespiratory fitness (d = 10.00, p = 0.030). Moreover, the adrenocorticotropic hormone levels were reduced during the exercise, and the cortisol levels showed the decreasing trend during and after the exercise, which was correlated with the change of cardiorespiratory fitness (r = 0.65, p<0.05). These results indicated the possible adaptogenic effects of Momordica charantia extract intake. Based on the findings, we suggest that Momordica charantia could be used as a source of adaptogenic supplement to alleviate the exercise- and environment-induced stress.

7.
Environ Health ; 18(1): 55, 2019 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-31200714

RESUMEN

BACKGROUND: Previous studies show that escalations in ambient temperature are among the risk factors for acute kidney injury (AKI). However, it has not been adequately studied in our location, Seoul, South Korea. In this study, we aimed to examine the association between ambient temperatures and AKI morbidity using emergency department (ED) visit data. METHODS: We obtained data on ED visits from the National Emergency Medical Center for 21,656 reported cases of AKI from 2010 to 2014. Time-stratified case-crossover design analysis based on conditional logistic regression was used to analyze short-term effects of ambient temperature on AKI after controlling for relevant covariates. The shape of the exposure-response curve, effect modification by individual demographic characteristics, season, and comorbidities, as well as lag effects, were investigated. RESULTS: The odds ratio (OR) per 1 °C increase at lag 0 was 1.0087 (95% confidence interval [CI]: 1.0041-1.0134). Risks were higher during the warm season (OR = 1.0149; 95% CI: 1.0065-1.0234) than during the cool season (OR = 1.0059; 95% CI: 1.0003-1.0116) and even higher above 22.3 °C (OR = 1.0235; 95% CI: 1.0230-1.0239). CONCLUSIONS: This study provides evidence that ED visits for AKI were associated with ambient temperature. Early detection and treatment of patients at risk is important in both clinical and economic concerns related to AKI.


Asunto(s)
Lesión Renal Aguda/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Calor/efectos adversos , Lesión Renal Aguda/etiología , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Estudios Cruzados , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , República de Corea/epidemiología , Factores de Riesgo , Estaciones del Año
8.
Int J Biometeorol ; 63(6): 787-800, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30798364

RESUMEN

Changes in the environmental heat stress need to be properly evaluated to manage the risk of heat-related illnesses, particularly in the context of climate change. The wet bulb globe temperature (WBGT) is a useful index for evaluating heat stress and anticipating conditions related to heat-related illness in the present climate, but projecting the WBGT with a sufficiently high temporal and spatial resolution remains challenging for future climate conditions. In this study, we developed a methodological framework for estimating the site-specific hourly resolution WBGT based on the output of general circulation models using only simple calculations. The method was applied to six sites in Japan and its performance was evaluated. The proposed method could reproduce the site-specific hourly resolution WBGT with a high accuracy. Based on the developed framework, we constructed future (2090s) projections under two different greenhouse gas emission pathways. These projections showed a consistent rise in the WBGT and thus the capacity to perform physically demanding activities is expected to decrease. To demonstrate the usefulness of the projected WBGT in planning adaptation measures, we identified the optimal working schedules which would minimize outdoor workers' exposure to heat at a specific site. The results show that a substantial shift in the working time is required in the future if outdoor workers are to compensate the effect of increased heat exposure only by changing their working hours. This methodological framework and the projections will provide local practitioners with useful information to manage the increased risk of heat stress under climate change.


Asunto(s)
Trastornos de Estrés por Calor , Exposición Profesional , Cambio Climático , Calor , Humanos , Japón , Temperatura
9.
Glob Chang Biol ; 24(11): 5391-5410, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30053344

RESUMEN

Myanmar is one of the mangrove-richest countries in the world, providing valuable ecosystem services to people. However, due to deforestation driven primarily by agricultural expansion, Myanmar's mangrove forest cover has declined dramatically over the past few decades, while what remains is still under pressure. To support management planning, accurate quantification of mangrove forest cover changes on a national scale is needed. In this study, we quantified Myanmar's mangrove forest cover changes between 2000 and 2014 using remotely sensed data, examined the environmental impacts of such changes, and estimated the changes in the economic values of mangrove ecosystem services in the country. Results indicate that Myanmar had a net mangrove loss of 191,122 ha over the study period. Since 2000, Myanmar has been losing mangrove forest cover at an alarming rate of 14,619 ha/year (2.2%/year). The loss was predominant in Rakhine and Ayeyarwady. The observed mangrove forest cover loss has resulted in decreased evapotranspiration, carbon stock, and tree cover percentage. Due to deforestation, Myanmar also suffered a net loss of 2,397 million US$/year in its mangrove ecosystem service value (i.e. 28.7% decrease from 2000), in which maintenance of fisheries nursery populations and habitat and coastal protection were among those services that were greatly affected. We suggest that intensive reforestation and mangrove protection programs be implemented immediately. Agroforestry and community forestry programs are encouraged in areas that are under immense pressure from paddy field expansion, fuelwood extraction, charcoal production, and fish and shrimp farming activities. Potential alternative sustainable solutions should include intensive government-led private forest plantations or community-owned forest plantations to be developed with care by local farmers, nongovernmental organizations, and business owners.


Asunto(s)
Conservación de los Recursos Naturales , Humedales , Agricultura , Ecosistema , Agricultura Forestal , Bosques , Árboles
10.
Environ Health Prev Med ; 19(1): 56-63, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23928946

RESUMEN

OBJECTIVES: We previously developed a model for projection of heat-related mortality attributable to climate change. The objective of this paper is to improve the fit and precision of and examine the robustness of the model. METHODS: We obtained daily data for number of deaths and maximum temperature from respective governmental organizations of Japan, Korea, Taiwan, the USA, and European countries. For future projection, we used the Bergen climate model 2 (BCM2) general circulation model, the Special Report on Emissions Scenarios (SRES) A1B socioeconomic scenario, and the mortality projection for the 65+-year-old age group developed by the World Health Organization (WHO). The heat-related excess mortality was defined as follows: The temperature-mortality relation forms a V-shaped curve, and the temperature at which mortality becomes lowest is called the optimum temperature (OT). The difference in mortality between the OT and a temperature beyond the OT is the excess mortality. To develop the model for projection, we used Japanese 47-prefecture data from 1972 to 2008. Using a distributed lag nonlinear model (two-dimensional nonparametric regression of temperature and its lag effect), we included the lag effect of temperature up to 15 days, and created a risk function curve on which the projection is based. As an example, we perform a future projection using the above-mentioned risk function. In the projection, we used 1961-1990 temperature as the baseline, and temperatures in the 2030s and 2050s were projected using the BCM2 global circulation model, SRES A1B scenario, and WHO-provided annual mortality. Here, we used the "counterfactual method" to evaluate the climate change impact; For example, baseline temperature and 2030 mortality were used to determine the baseline excess, and compared with the 2030 excess, for which we used 2030 temperature and 2030 mortality. In terms of adaptation to warmer climate, we assumed 0 % adaptation when the OT as of the current climate is used and 100 % adaptation when the OT as of the future climate is used. The midpoint of the OTs of the two types of adaptation was set to be the OT for 50 % adaptation. RESULTS: We calculated heat-related excess mortality for 2030 and 2050. CONCLUSIONS: Our new model is considered to be better fit, and more precise and robust compared with the previous model.


Asunto(s)
Cambio Climático/mortalidad , Calor/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Modelos Teóricos , Medición de Riesgo , Adulto Joven
11.
Temperature (Austin) ; 11(1): 92-106, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577294

RESUMEN

Thermal safety guidelines with upper thresholds aim to protect athletes' health, yet evidence-based sport-specific thresholds remain unestablished. Experimenting with athletes in severely hot conditions raises ethical concerns, so we used a thermo-physiological model to validate the thresholds of guidelines for outdoor sports. First, the reproducibility of the joint system thermoregulation model (JOS-3) of core temperature has been validated for 18 sports experiments (n = 213) and 11 general exercise experiments (n = 121) using the Bland - Altman analysis. Then, core temperatures were predicted using the JOS-3 in conditions corresponding to the upper thresholds, and if the 90th-99.7th percentile core temperature value (corresponding to 0.3%-10% of the participants) exceeded 40°C, the thresholds were judged as potentially hazardous. Finally, we proposed revisions for sports with potentially hazardous thresholds. As a result, the JOS-3 could simulate core temperature increases in most experiments (27/29) for six sports and general exercises with an accuracy of 0.5°C. The current upper thresholds for marathons, triathlons, and football are potentially hazardous. Suggested revisions, based on specified percentiles, include: Football: revise from wet bulb globe temperature (WBGT) 32°C to 29-31°C or not revise. Marathon: revise from WBGT 28°C to 24-27°C. Triathlon: revise from WBGT 32.2°C to 23-26°C. If conducting sports events under the revised upper thresholds proves difficult, taking measures for a possible high incidence of heat illness becomes crucial, such as placing additional medical resources, assisting heat acclimatization and cooling strategies for participants, and rule changes such as shorter match times and increased breaks.

12.
Environ Health Perspect ; 131(5): 57005, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37172196

RESUMEN

BACKGROUND: The health effects of heat are well documented; however, limited information is available regarding the health risks of hot nights. Hot nights have become more common, increasing at a faster rate than hot days, making it urgent to understand the characteristics of the hot night risk. OBJECTIVES: We estimated the effects of hot nights on the cause- and location-specific mortality in a nationwide assessment over 43 y (1973-2015) using a unified analytical framework in the 47 prefectures of Japan. METHODS: Hot nights were defined as days with a) minimum temperature ≥25°C (HN25) and b) minimum temperature ≥95th percentile (HN95th) for the prefecture. We conducted a time-series analysis using a two-stage approach during the hot night occurrence season (April-November). For each prefecture, we estimated associations between hot nights and mortality controlling for potential confounders including daily mean temperature. We then used a random-effects meta-analytic model to estimate the pooled cumulative association. RESULTS: Overall, 24,721,226 deaths were included in this study. Nationally, all-cause mortality increased by 9%-10% [HN25 relative risk (RR)=1.09, 95% confidence interval (CI): 1.08, 1.10; HN95th RR=1.10, 95% CI: 1.09, 1.11] during hot nights in comparison with nonhot nights. All 11 cause-specific mortalities were strongly associated with hot nights, and the corresponding associations appeared to be acute and lasted a few weeks, depending on the cause of death. The strength of the association between hot nights and mortality varied among prefectures. We found a higher mortality risk from hot nights in early summer in comparison with the late summer in all regions. CONCLUSIONS: Our findings support the evidence of mortality impacts from hot nights in excess of that explicable by daily mean temperature and have implications useful for establishing public health policy and research efforts estimating the health effects of climate change. https://doi.org/10.1289/EHP11444.


Asunto(s)
Calor , Mortalidad , Estudios Retrospectivos , Japón/epidemiología , Temperatura , Estaciones del Año
13.
Sci Total Environ ; 836: 155569, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35490818

RESUMEN

Climate change and anthropogenic activities are affecting the hydrological conditions of rivers and may have altered nutrient and suspended sediments released into coastal seas. However, testing this hypothesis is difficult, confounded by the lack of observational data and the unavailability of globally accepted suspended sediment concentration (SSC) algorithms. Here, we analyzed the trends in SSC (2000-2020) at the mouths of 10 major Asian rivers using 10 available satellite-SSC algorithms. We identified spatially distinct trends, with SSC decreasing at the mouths of the Yellow, Pearl, and Indus rivers, and increasing trends at the mouths of the Narmada and Ganges-Brahmaputra rivers, while there were no significant trends at the mouths of the remaining rivers. River discharge, dams, and land use changes in basins individually did not suffice, but reproduced the observed SSC trends when used together. Our results imply that anthropogenic activities threaten the marine ecosystem more than climate forcing on Asian coasts.


Asunto(s)
Estuarios , Sedimentos Geológicos , Ecosistema , Monitoreo del Ambiente , Hidrología , Ríos
14.
Sci Rep ; 12(1): 4010, 2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-35256734

RESUMEN

There are concerns about the impact of climate change on Olympic Games, especially endurance events, such as marathons. In recent competitions, many marathon runners dropped out of their races due to extreme heat, and it is expected that more areas will be unable to host the Games due to climate change. Here, we show the feasibility of the Olympic marathon considering the variations in climate factors, socioeconomic conditions, and adaptation measures. The number of current possible host cities will decline by up to 27% worldwide by the late twenty-first century. Dozens of emerging cities, especially in Asia, will not be capable of hosting the marathon under the highest emission scenario. Moving the marathon from August to October and holding the Games in multiple cities in the country are effective measures, and they should be considered if we are to maintain the regional diversity of the Games.


Asunto(s)
Calor Extremo , Carrera , Estudios de Factibilidad , Carrera de Maratón , Factores Socioeconómicos
15.
Sci Total Environ ; 824: 153697, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35143798

RESUMEN

Climate change has the potential to cause forest range shifts at a broad scale and consequently can alter crucial forest functions, including carbon sequestration. However, global-scale projections of future forest range shifts remain challenging because our knowledge of the physiological responses of plants to climatic stress is limited to particular species and is insufficient for wide-range projections, in addition to the uncertainties in the impacts of non-climatic factors, such as wildfire, wind, and insect outbreaks. To evaluate the vulnerability and resilience of forests to climate change, we developed a new empirical approach using climatic indices reflecting physiological stressors on plants. We calculated the global distributions of seven indices based on primary climatic stressors (drought, solar radiation, and temperature) at high resolution. We then modeled the relationship between the seven indices and global forest extent. We found two key stressors driving climate-induced forest range shifts on a global scale: low temperature under high radiation and drought. At high latitudes of the Northern Hemisphere, forest establishment became difficult when the mean temperature was less than approximately 7.2 °C in the highest radiation quarter. Forest sensitivity to drought was more pronounced at mid-latitudes. In areas where the humidity index (ratio of precipitation to potential evapotranspiration) was below 0.45, shrubland and grassland became more dominant than forests. Our results also suggested that the impacts of climate change on global forest range shifts will be geographically biased depending on the areas affected by the key climatic stressors. Potential forest gain was remarkable in boreal regions due to increasing temperature. Potential forest loss was remarkable in current tropical grassland and temperate forest/grassland ecoregions due to increasing drought. Our approach using stress-reflecting indices could improve our ability to detect the roles of climatic stressors on climate-induced forest range shifts.


Asunto(s)
Bosques , Árboles , Cambio Climático , Sequías , Temperatura , Árboles/fisiología
16.
Sci Total Environ ; 845: 157312, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35839873

RESUMEN

BACKGROUND: Environmental factors have been associated with adverse health effects in epidemiological studies. The main exposure variable is usually determined via prior knowledge or statistical methods. It may be challenging when evidence is scarce to support prior knowledge, or to address collinearity issues using statistical methods. This study aimed to investigate the importance level of environmental variables for the under-five mortality in Malaysia via random forest approach. METHOD: We applied a conditional permutation importance via a random forest (CPI-RF) approach to evaluate the relative importance of the weather- and air pollution-related environmental factors on daily under-five mortality in Malaysia. This study spanned from January 1, 2014 to December 31, 2016. In data preparation, deviation mortality counts were derived through a generalized additive model, adjusting for long-term trend and seasonality. Analyses were conducted considering mortality causes (all-cause, natural-cause, or external-cause) and data structures (continuous, categorical, or all types [i.e., include all variables of continuous type and all variables of categorical type]). The main analysis comprised of two stages. In Stage 1, Boruta selection was applied for preliminary screening to remove highly unimportant variables. In Stage 2, the retained variables from Boruta were used in the CPI-RF analysis. The final importance value was obtained as an average value from a 10-fold cross-validation. RESULT: Some heat-related variables (maximum temperature, heat wave), temperature variability, and haze-related variables (PM10, PM10-derived haze index, PM10- and fire-derived haze index, fire hotspot) were among the prominent variables associated with under-five mortality in Malaysia. The important variables were consistent for all- and natural-cause mortality and sensitivity analyses. However, different most important variables were observed between natural- and external-cause under-five mortality. CONCLUSION: Heat-related variables, temperature variability, and haze-related variables were consistently prominent for all- and natural-cause under-five mortalities, but not for external-cause.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Exposición a Riesgos Ambientales/análisis , Calor , Malasia/epidemiología , Mortalidad , Material Particulado/análisis , Tiempo (Meteorología)
17.
Nat Food ; 2(8): 587-595, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37118168

RESUMEN

Climate change is expected to increase the frequency, intensity and spatial extent of extreme climate events, and thus is a key concern for food production. However, food insecurity is usually analysed under a mean climate change state. Here we combine crop modelling and climate scenarios to estimate the effects of extreme climate events on future food insecurity. Relative to median-level climate change, we find that an additional 20-36% and 11-33% population may face hunger by 2050 under a once-per-100-yr extreme climate event under high and low emission scenarios, respectively. In some affected regions, such as South Asia, the amount of food required to offset such an effect is triple the region's current food reserves. Better-targeted food reserves and other adaptation measures could help fill the consumption gap in the face of extreme climate variability.

18.
Sci Total Environ ; 731: 139012, 2020 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-32388159

RESUMEN

Human life comes to a standstill as many countries shut themselves off from the work due to the novel coronavirus disease pandemic (COVID-19) that hit the world severely in the first quarter of 2020. All types of industries, vehicle movement, and people's activity suddenly halted, perhaps for the first time in modern history. For a long time, it has been stated in various literature that the increased industrialization and anthropogenic activities in the last two decades polluted the atmosphere, hydrosphere, and biosphere. Since the industries and people's activities have been shut off for a month or more in many parts of the world, it is expected to show some improvement in the prevailing conditions in the aforementioned spheres of environment. Here, with the help of remote sensing images, this work quantitatively demonstrated the improvement in surface water quality in terms of suspended particulate matter (SPM) in the Vembanad Lake, the longest freshwater lake in India. The SPM estimated based on established turbidity algorithm from Landsat-8 OLI images showed that the SPM concentration during the lockdown period decreased by 15.9% on average (range: -10.3% to 36.4%, up to 8 mg/l decrease) compared with the pre-lockdown period. Time series analysis of satellite image collections (April 2013 - April 2020) showed that the SPM quantified for April 2020 is the lowest for 11 out of 20 zones of the Vembanad lake. When compared with preceding years, the percentage decrease in SPM for April 2020 is up to 34% from the previous minima.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Lagos , Pandemias , Neumonía Viral , Calidad del Agua , COVID-19 , Monitoreo del Ambiente , Humanos , India , SARS-CoV-2
19.
Ambio ; 49(12): 1972-1981, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32378037

RESUMEN

The conceptualization of the Shared Socioeconomic Pathways (SSPs) framework represented a major leap in scenario development in the context of global environmental change and sustainability, providing significant advances from the previous scenario frameworks-especially the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios. It is highly likely that the SSP concept, along with its scenario narratives and their respective results, including land-use change projections, will play a substantial role in the forthcoming Sixth Assessment Report by the IPCC. Here, we offer some insights that could make the SSPs' projected future changes in global land use more comprehensive and also help improve the interpretability of such projections. For example, instead of focusing on the quantity of each land-use class at various time points which results only in a net change when change is detected between time points, we recommend that the projected gross gains and gross losses in each land-use class across all scenarios should also be considered. Overall, the insights presented could also help pave the way for stronger collaboration between the SSP-climate science community and the land system science community; such collaboration is much needed in addressing the challenges of global environmental change towards a climate-resilient sustainable development pathway.


Asunto(s)
Cambio Climático , Predicción , Factores Socioeconómicos
20.
Nat Commun ; 11(1): 1581, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32221303

RESUMEN

More than half of the world's population currently live in urban areas and are particularly at risk from the combined effects of the urban heat island phenomenon and heat increases due to climate change. Here, by using remotely sensed surface temperature data and social-ecological indicators, focusing on the hot dry season, and applying the risk framework of the Intergovernmental Panel on Climate Change, we assessed the current heat health risk in 139 Philippine cities, which account for about 40% of the country's total population. The cities at high or very high risk are found in Metro Manila, where levels of heat hazard and exposure are high. The most vulnerable cities are, however, found mainly outside the national capital region, where sensitivity is higher and capacity to cope and adapt is lower. Cities with high levels of heat vulnerability and exposure must be prioritized for adaptation. Our results will contribute to risk profiling in the Philippines and to the understanding of city-level heat health risks in developing regions of the Asia-Pacific.


Asunto(s)
Fenómenos Ecológicos y Ambientales , Calor , Tecnología de Sensores Remotos , Medición de Riesgo , Ciudades , Geografía , Humanos , Filipinas , Riesgo
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