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The advance of human activities in a disorderly way has accelerated in recent decades, intensifying the environmental impacts directly linked to these practices. The atmosphere, essential for the maintenance of life, is increasingly saturated with pollutants, offering risks to practically all the inhabitants of the planet, a process that, in addition to causing illness and early mortality, is related to serious financial losses (including in the production of goods), dangerous temperature increase and severe natural disasters. Although this perception is not recent, the global initiative to control the different mechanisms that trigger the commitment of biodiversity and irreversible climate changes arising from pollution is still very incipient, given that global initiatives on the subject emerged just over 50 years ago. Brazil is a territory that centralizes many of these discussions, as it still faces both political and economic obstacles in achieving a sustainable growth model as it was agreed through the United Nations 2030 Agenda. Even though there is little time left for the completion of these goals, much remains to be done, and despite the fulfillment of this deadline, the works will certainly need to be extended for much longer until an effective reorientation of consciousness occurs. Scientific researches and discussions are fundamental tools to the understanding of issues still little explored in this field. [ABSTRACT FROM AUTHOR]

Frequent heat waves and mass mortality events on marine biota are positively correlated to ocean warming. Although literature has indicated some species of marine sponges, and some oceanic regions, like the Brazilian Exclusive Economic Zone, may be less affected or seem to be more resilient under future scenarios of climate changes, few studies have focused on the species responses on the climate change issue along Brazilian coast. This paradigm was undone throughout 2019 after an exceptional average increase of 2 °C in the sea surface temperature (SST) and on precipitation values since 2015 at Ilha Grande Bay (IGB, SE Brazil). The combination of SST and precipitation average increase possibly favored an environmental context for the unprecedented strong population decline and mass mortality rate of the marine sponge species Desmapsamma anchorata in the austral spring. The species used to be one of the most frequent benthic species at IGB however it was only recorded in 41.7% sites (n = 12). From 162 individuals recorded at Abraãozinho along 180 m rocky shore, 83 individuals (51.2%) were healthy, 74 (45.7%) were intensively covered by cyanobacteria and locally bleached, and five (3.1%) were completely bleached or died. Desmapsamma anchorata population deterioration in a biogeographic transition zone (Rio de Janeiro state) may reflect a shift in the marine community of IGB, opening space for opportunistic species establishment and coverage increase, since IGB has a high species turnover. The three-dimensionality, the shelter for several species, the high competitive ability and the potential to indicate polluted or not polluted areas make D. anchorata a key species for IGB monitoring in a climate change scenario. [ABSTRACT FROM AUTHOR]

Temperature record-breaking events, such as the observed more intense, longer-lasting, and more frequent heat waves, pose a new global challenge to health sectors worldwide. These threats are of particular interest in low-income regions with limited investments in public health and a growing urban population, such as Brazil. Here, we apply a comprehensive interdisciplinary climate-health approach, including meteorological data and a daily mortality record from the Brazilian Health System from 2000 to 2015, covering 21 cities over the Metropolitan Region of Rio de Janeiro. The percentage of absolute mortality increase due to summer extreme temperatures is estimated using a negative binomial regression modeling approach and maximum/minimum temperature-derived indexes as covariates. Moreover, this study assesses the vulnerability to thermal stress for different age groups and both genders and thoroughly analyzes four extremely intense heat waves during 2010 and 2012 regarding their impacts on the population. Results showed that the highest absolute mortality values during heat-related events were linked to circulatory illnesses. However, the highest excess of mortality was related to diabetes, particularly for women within the elderly age groups. Moreover, results indicate that accumulated heat stress conditions during consecutive days preferentially preceded by persistent periods of moderate-temperature, lead to higher excess mortality rather than sporadic single hot days. This work may provide directions in human health policies related to extreme climate events in large tropical metropolitan areas from developing countries, contributing to altering the historically based purely reactive response. [ABSTRACT FROM AUTHOR]

Extreme temperatures have caused various damages to society around the world. In Brazil, an example of that is the impact of cold and heat waves on public health. In order to analyse the temporal and spatial variability of such events, this study applied a single criterion to identify cold and heat waves. The study collected data on the events from daily temperature records from 264 weather stations over 56 years (1961–2016). The following parameters were used to describe each event: frequency, duration, severity, and intensity. The results showed that in all the Brazilian regions the frequency of heat waves increased and that of cold waves decreased between the years 1961 and 2016. The number of heat waves per year, notably, was greater than that of cold waves, and the mean duration of heat waves was about 1 day longer than that of cold waves. Additionally, it was found that cold waves were more severe and intense in areas often reached by cold air masses with temperatures below zero in most of Southern Brazil. In terms of severity and intensity of heat waves, two different configurations were observed: They were more severe in the Southern region and more intense in the Midwestern region of the country, and not so expressive in the Northern and Northeastern regions. Those findings justify the need for continuous updating of public policies focused on sectors often affected by cold and heat. [ABSTRACT FROM AUTHOR]

Background: The Brazilian Amazon faces overlapping socio-environmental, sanitary, and climate challenges, and is a hotspot of concern due to projected increases in temperature and in the frequency of heat waves. Understanding the effects of extreme events on health is a central issue for developing climate policies focused on the population's health., Objectives: We investigated the effects of heat waves on mortality in the Brazilian Amazon, examining effect modification according to various heat wave definitions, population subgroups, and causes of death., Methods: We included all 32 Amazonian municipalities with more than 100,000 inhabitants. The study period was from 2000 to 2018. We obtained mortality data from the Information Technology Department of the Brazilian Public Healthcare System, and meteorological data were derived from the ERA5-Land reanalysis dataset. Heat waves were defined according to their intensity (90th; 92.5th; 95th; 97.5th and 99th temperature percentiles) and duration (≥2, ≥3, and ≥4 days). In each city, we used a time-stratified case-crossover study to estimate the effects of each heat wave definition on mortality, according to population subgroup and cause of death. The lagged effects of heat waves were estimated using conditional Poisson regression combined with distributed lag non-linear models. Models were adjusted for specific humidity and public holidays. Risk ratios were pooled for the Brazilian Amazon using a univariate random-effects meta-analysis., Results: The pooled relative risks (RR) for mortality from total non-external causes varied between 1.03 (95% CI: 1.01-1.06), for the less stringent heat wave definition, and 1.18 (95% CI: 1.04-1.33) for the more stringent definition. The mortality risk rose as the heat wave intensity increased, although the increase from 2 to 3, and 3-4 days was small. Although not statistically different, our results suggest a higher mortality risk for the elderly, this was also higher for women than men, and for cardiovascular causes than for non-external or respiratory ones., Conclusions: Heat waves were associated with a higher risk of mortality from non-external causes and cardiovascular diseases. Heat wave intensity played a more important role than duration in determining this risk. Suggestive evidence indicated that the elderly and women were more vulnerable to the effects of heat waves on mortality., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

Understanding how weather impacts health is critical, especially under a changing climate; however, relatively few studies have investigated subtropical regions. We examined how mortality in São Paulo, Brazil, is affected by cold, heat, and heat waves over 14.5 years (1996-2010). We used over-dispersed generalized linear modeling to estimate heat- and cold-related mortality, and Bayesian hierarchical modeling to estimate overall effects and modification by heat wave characteristics (intensity, duration, and timing in season). Stratified analyses were performed by cause of death and individual characteristics (sex, age, education, marital status, and place of death). Cold effects on mortality appeared higher than heat effects in this subtropical city with moderate climatic conditions. Heat was associated with respiratory mortality and cold with cardiovascular mortality. Risk of total mortality was 6.1 % (95 % confidence interval 4.7, 7.6 %) higher at the 99th percentile of temperature than the 90th percentile (heat effect) and 8.6 % (6.2, 11.1 %) higher at the 1st compared to the 10th percentile (cold effect). Risks were higher for females and those with no education for heat effect, and males for cold effect. Older persons, widows, and non-hospital deaths had higher mortality risks for heat and cold. Mortality during heat waves was higher than on non-heat wave days for total, cardiovascular, and respiratory mortality. Our findings indicate that mortality in São Paulo is associated with both cold and heat and that some subpopulations are more vulnerable. [ABSTRACT FROM AUTHOR]

According to IPCC predictions for 2100, increasing CO concentrations and global mean temperature could lead to a future scenario of increased incidence and duration of periods with exceptionally high temperatures and duration of drier seasons in some locations like Central Brazil. This extreme weather can affect fragile environments which are already suffering from anthropogenic disturbance that eventually culminate in biological invasions. One of these environments is the Brazilian Savanna (Cerrado), a biome with high levels of endemism, being considered an extremely important area for conservation. The present study aimed to investigate whether elevated CO and temperature could modify protoplasmic tolerance to induced water deficit and acute heat shock in three species of invasive African grasses that are gradually replacing the Cerrado landscape. Results obtained from leaf tissues showed that elevated CO and temperature had no effect on protoplasmic tolerances of Urochloa brizantha and that Megathyrsus maximus showed decreased thermotolerance. Urochloa decumbens showed improved tolerance responses to both types of these constraints undergone in vitro. Such adaptations to climate changes would probably represent an advantage in competition with other species. The results indicate that elevated CO and temperature could cause modifications to protoplasmic responses of invasive grasses. The effects caused, however, depend on the species investigated. This ability to adapt or not to a changing environment may affect species distribution in natural and anthropized environments, especially in a future with predicted extreme weather. [ABSTRACT FROM AUTHOR]

Given the increase in the frequency, intensity, and persistence of heat waves since the 1970s, and in view of the impacts that extreme temperatures may cause for society and the economy, this study aims to characterize heat waves in the subtropical region of Brazil and compare findings with the criterion defined by the World Meteorological Organization (WMO). Daily maximum temperature data was used. By using the percentile methodology, the subtropical region was divided into two regions: region 1 and region 2. We identified 54 heat waves in region 1 and 34 in region 2, which occurred more frequently in winter and spring, and less frequently in summer. A close relationship was observed between the Pacific Decadal Oscillation (PDO) and El Niño–Southern Oscillation (ENSO), both of which are able to modulate the heat waves in each of the different regions. Region 1 presented the highest number of heat waves during the warm (cold) phase of the PDO. As for ENSO, heat waves were more frequent in the neutral phase in both regions. Finally, there was shown to be an increase in the frequency and persistence of heat waves since the 1980s, especially in region 2. The methodology used in this study allows the identification and characterization of heat waves in several regions of different climates. [ABSTRACT FROM AUTHOR]