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1.
Front Public Health ; 10: 962377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091554

RESUMO

Malaria is the cause of nearly half a million deaths worldwide each year, posing a great socioeconomic burden. Despite recent progress in understanding the influence of climate on malaria infection rates, climatic sources of predictability remain poorly understood and underexploited. Local weather variability alone provides predictive power at short lead times of 1-2 months, too short to adequately plan intervention measures. Here, we show that tropical climatic variability and associated sea surface temperature over the Pacific and Indian Oceans are valuable for predicting malaria in Limpopo, South Africa, up to three seasons ahead. Climatic precursors of malaria outbreaks are first identified via lag-regression analysis of climate data obtained from reanalysis and observational datasets with respect to the monthly malaria case count data provided from 1998-2020 by the Malaria Institute in Tzaneen, South Africa. Out of 11 sea surface temperature sectors analyzed, two regions, the Indian Ocean and western Pacific Ocean regions, emerge as the most robust precursors. The predictive value of these precursors is demonstrated by training a suite of machine-learning classification models to predict whether malaria case counts are above or below the median historical levels and assessing their skills in providing early warning predictions of malaria incidence with lead times ranging from 1 month to a year. Through the development of this prediction system, we find that past information about SST over the western Pacific Ocean offers impressive prediction skills (~80% accuracy) for up to three seasons (9 months) ahead. SST variability over the tropical Indian Ocean is also found to provide good skills up to two seasons (6 months) ahead. This outcome represents an extension of the effective prediction lead time by about one to two seasons compared to previous prediction systems that were more computationally costly compared to the machine learning techniques used in the current study. It also demonstrates the value of climatic information and the prediction framework developed herein for the early planning of interventions against malaria outbreaks.


Assuntos
Clima , Malária , Surtos de Doenças , Humanos , Aprendizado de Máquina , Malária/epidemiologia , África do Sul/epidemiologia , Temperatura
2.
Proc Natl Acad Sci U S A ; 119(37): e2208629119, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067289

RESUMO

Insular woodiness (IW)-the evolutionary transition from herbaceousness toward woodiness on islands-is one of the most iconic features of island floras. Since pioneering work by Darwin and Wallace, a number of drivers of IW have been proposed, such as 1) competition for sunlight requiring plants with taller and stronger woody stems and 2) drought favoring woodiness to safeguard root-to-shoot water transport. Alternatively, IW may be the indirect result of increased lifespan related to 3) a favorable aseasonal climate and/or 4) a lack of large native herbivores. However, information on the occurrence of IW is fragmented, hampering tests of these potential drivers. Here, we identify 1,097 insular woody species on 375 islands and infer at least 175 evolutionary transitions on 31 archipelagos, concentrated in six angiosperm families. Structural equation models reveal that the insular woody species richness on oceanic islands correlates with a favorable aseasonal climate, followed by increased drought and island isolation (approximating competition). When continental islands are also included, reduced herbivory pressure by large native mammals, increased drought, and island isolation are most relevant. Our results illustrate different trajectories leading to rampant convergent evolution toward IW and further emphasize archipelagos as natural laboratories of evolution, where similar abiotic or biotic conditions replicated evolution of similar traits.


Assuntos
Ilhas , Madeira , Evolução Biológica , Clima , Oceanos e Mares , Plantas
3.
Science ; 377(6610): 1031, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36048930

RESUMO

Nearly complete specimen shows earliest dinosaurs needed a temperate climate.


Assuntos
Evolução Biológica , Clima , Dinossauros , Fósseis , Animais , Dinossauros/anatomia & histologia , Filogenia , Zimbábue
4.
Science ; 377(6611): 1135, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36074846

RESUMO

Scientists call for concerted effort to forecast points of no return for ice, weather patterns, and ecosystems.


Assuntos
Clima , Ecossistema , Mudança Climática , Previsões
5.
Zootaxa ; 5154(4): 454-468, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-36095610

RESUMO

The presence of cryptic species is one of the important problems in systematics. To deal with this systematic issue, certain approaches have been utilized. DNA sequencing is one of the common techniques for estimating biodiversity, such as DNA barcoding, which might reveal cryptic species. In this study, we explore how to identify two cryptic saproxylic species using a combination of general and aedeagus morphologies, distributional patterns (in provinces and altitude), specimen abundance, ecological niche modeling (ENM), and mtDNA sequencing data (for the endemic species Ampedus platiai and A. samedovi). The close relationship and validity of these species based on classical systematics was confirmed by the available literature and by Neighbor-Joining (NJ) analysis in Mega Software. Additionally, the DNA barcoding data acquired in this study also confirmed the species status of these species within the genus Ampedus. This also provides insights into classical systematics. ENMs for possible current and future distributional scenarios of endemic A. platiai and A. samedovi are created by Maxent Software. Possible suitable habitats in 2050 and 2070 for the species are calculated according to IPCC5 Climate scenarios. Precipitation seasonality (coefficient of variation) has the highest percentage contribution to the resulting prediction pattern for A. platiai (52.3), the mean temperature of the wettest quarter has the highest percentage contribution to the resulting prediction pattern for A. samedovi (42.7) respectively among used bioclimatic variables in ENM. Depending on the temperature increase in 2050 and 2070, the distributions of A. platiai and A. samedovi could decrease gradually.


Assuntos
Besouros , Animais , Biodiversidade , Clima , Besouros/genética , DNA/genética , Código de Barras de DNA Taxonômico , Ecossistema
8.
BMJ ; 378: o2238, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104066

Assuntos
Clima , Humanos , Reino Unido
9.
Sci Rep ; 12(1): 15322, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097009

RESUMO

Using semen data from 1271 ejaculates (79 different bulls, 11 different breeds) we have investigated the variability of semen quality in cattle living in sub-tropical conditions. Modelling shows definitive evidence of seasonal variation. Semen quality from the same bulls had a 90% "pass rate" for cryopreservation purposes in winter, dropping to less than 50% in summer. Notably, individual bulls could be classified as either "heat-tolerant" (produce good quality spermatozoa all year regardless of temperature) or "heat-sensitive" (only produce good quality sperm in summer). Nominal logistic regression demonstrated when temperatures reach 30.5 °C, 40% of heat-sensitive bulls fail a semen analysis 17 days later. At 34 °C, the proportion of bulls failing reached 63%. Ratifying this, the purposeful heating of bulls to 40 °C for 12 h showed that individual animals had different degrees of heat-sensitivity. Using historical temperature data, we then modelled how many days/decade bulls would be subject to heat-events. Beginning from 1939 to 1949, on average, the area in which bulls were kept recorded 19, 7 and 1 day over 38 °C, 39 °C and 40 °C respectively. This number steadily increases and of last decade (2010-2010), the numbers of days per decade over 38 °C, 39 °C and 40 °C jumped to a staggering 75, 39 and 15 respectively. These data show the urgent need to identify heat-tolerant bulls as future sires. Such variation likely explains why the veterinary bull breeding test often fails to accurately predict bull breeding potential.


Assuntos
Análise do Sêmen , Sêmen , Animais , Bovinos , Clima , Temperatura Alta , Masculino , Estações do Ano , Análise do Sêmen/veterinária
10.
Sci Rep ; 12(1): 15320, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097179

RESUMO

The detection of cause-effect relationships from the analysis of paleoclimatic records is a crucial step to disentangle the main mechanisms at work in the climate system. Here, we show that the approach based on the generalized Fluctuation-Dissipation Relation, complemented by the analysis of the Transfer Entropy, allows the causal links to be identified between temperature, CO[Formula: see text] concentration and astronomical forcing during the glacial cycles of the last 800 kyr based on Antarctic ice core records. When considering the whole spectrum of time scales, the results of the analysis suggest that temperature drives CO[Formula: see text] concentration, or that are both driven by the common astronomical forcing. However, considering only millennial-scale fluctuations, the results reveal the presence of more complex causal links, indicating that CO[Formula: see text] variations contribute to driving the changes of temperature on such time scales. The results also evidence a slow temporal variability in the strength of the millennial-scale causal links between temperature and CO[Formula: see text] concentration.


Assuntos
Clima , Regiões Antárticas , Causalidade , Temperatura
11.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(7): 777-781, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36100422

RESUMO

With global warming and frequent heat waves, the incidence of heat-related-illness has gradually increased, and heatstroke is the most serious clinical syndrome, with high mortality and incidence of sequelae. Effective heatstroke warning aims to reduce the incidence and the harm of heatstroke by monitoring certain parameters and forecasting the possibility of suffering heat illness, however, there is no unified summary of the heatstroke early warning system at present. The occurrence of heatstroke involves two key aspects: climate environment and individual susceptibility, and individual susceptibility is manifested as the difference in heat tolerance ability. This article represents the current early warning system of heatstroke from climate environment, such as effective temperature, heat index, wet bulb globe temperature (WBGT) index, somatosensory temperature, etc., and individual susceptibility, for the reference of research and development in this field.


Assuntos
Transtornos de Estresse por Calor , Golpe de Calor , Clima , Transtornos de Estresse por Calor/complicações , Golpe de Calor/complicações , Temperatura Alta , Humanos , Temperatura
12.
Artigo em Inglês | MEDLINE | ID: mdl-36078825

RESUMO

Since the COVID-19 outbreak, the scientific community has been trying to clarify various problems, such as the mechanism of virus transmission, environmental impact, and socio-economic impact. The spread of COVID-19 in the atmospheric environment is variable and uncertain, potentially resulting in differences in air pollution. Many scholars are striving to explore the relationship between air quality, meteorological indicators, and COVID-19 to understand the interaction between COVID-19 and the atmospheric environment. In this study, we try to summarize COVID-19 studies related to the atmospheric environment by reviewing publications since January 2020. We used metrological methods to analyze many publications in Web of Science Core Collection. To clarify the current situation, hotspots, and development trends in the field. According to the study, COVID-19 research based on the atmospheric environment has attracted global attention. COVID-19 and air quality, meteorological factors affecting the spread of COVID-19, air pollution, and human health are the main topics. Environmental variables have a certain impact on the spread of SARS-CoV-2, and the prevalence of COVID-19 has improved the atmospheric environment to some extent. The findings of this study will aid scholars to understand the current situation in this field and provide guidance for future research.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , COVID-19/epidemiologia , Clima , Humanos , Pandemias , SARS-CoV-2
13.
Sci Rep ; 12(1): 15064, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36065006

RESUMO

Food systems (FSs) emit ~ 20 GtCO2e/y (~ 35% of global greenhouse gas emissions). This level tends to raise given the expected increases in food demands, which may threaten global climate targets. Through a rapid assessment, evaluating 60+ scenarios based on existing low-emission and carbon sequestration practices, we estimate that intensifying FSs could reduce its emissions from 21.4 to - 2.0 GtCO2e/y and address increasing food demands without relying on carbon offsets (e.g., related to afforestation and reforestation programs). However, given historical trends and regional contexts, a more diverse portfolio of practices, including diet shifts and new-horizon technologies, will be needed to increase the feasibility of achieving net-zero FSs. One likely pathway consists of implementing practices that shift food production to the 30th-percentile of least emission-intensive FSs (~ 45% emissions reduction), sequester carbon at 50% of its potential (~ 5 GtCO2e/y) and adopt diet shifts and new-horizon technologies (~ 6 GtCO2e/y). For a successful transition to happen, the global FSs would, in the next decade (2020s), need to implement cost-effective mitigation practices and technologies, supported by improvements in countries' governance and technical assistance, innovative financial mechanisms and research focused on making affordable technologies in the following two decades (2030-2050). This work provides options and a vision to guide global FSs to achieving net-zero by 2050.


Assuntos
Sequestro de Carbono , Gases de Efeito Estufa , Carbono , Clima , Alimentos , Efeito Estufa
14.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080866

RESUMO

The novel concept of local climate zones (LCZs) provides a consistent classification framework for studies of the urban thermal environment. However, the development of urban climate science is severely hampered by the lack of high-resolution data to map LCZs. Using Gaofen-6 and Sentinel-1/2 as data sources, this study designed four schemes using convolutional neural network (CNN) and random forest (RF) classifiers, respectively, to demonstrate the potential of high-resolution images in LCZ mapping and evaluate the optimal combination of different data sources and classifiers. The results showed that the combination of GF-6 and CNN (S3) was considered the best LCZ classification scheme for urban areas, with OA and kappa coefficients of 85.9% and 0.842, respectively. The accuracy of urban building categories is above 80%, and the F1 score for each category is the highest, except for LCZ1 and LCZ5, where there is a small amount of confusion. The Sentinel-1/2-based RF classifier (S2) was second only to S3 and superior to the combination of GF-6 and random forest (S1), with OA and kappa coefficients of 64.4% and 0.612, respectively. The Sentinel-1/2 and CNN (S4) combination has the worst classification result, with an OA of only 39.9%. The LCZ classification map based on S3 shows that the urban building categories in Xi'an are mainly distributed within the second ring, while heavy industrial buildings have started to appear in the third ring. The urban periphery is mainly vegetated and bare land. In conclusion, CNN has the best application effect in the LCZ mapping task of high-resolution remote sensing images. In contrast, the random forest algorithm has better robustness in the band-abundant Sentinel data.


Assuntos
Clima , Redes Neurais de Computação , Algoritmos , Armazenamento e Recuperação da Informação
15.
Lancet ; 400(10354): 719-720, 2022 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-36058212
16.
Ying Yong Sheng Tai Xue Bao ; 33(7): 1975-1982, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36052802

RESUMO

In recent decades, extreme climate occurred frequently on the Loess Plateau. It is thus particularly important to study and predict the occurrence of extreme climate. Available researches on extreme climate mainly focus on the changing characteristics of the event itself, but ignore the correlation between average temperature and its changing trend. We used linear trend estimation, Mann-Kendall test, sliding t test and Pearson correlation analy-sis to study the variation trend of extreme temperature and its correlation with average temperature on the Loess Plateau based on the daily maximum temperature, minimum temperature and average temperature data of 79 meteo-rological stations from 1986 to 2019. The results showed that the extreme warmth index in the Loess Plateau region showed a significant upward trend, the extreme cold index showed a significant downward trend, and the frequency of extreme high temperature events increased. Most of the extreme temperature indices had abrupt changes in the middle and late 1990s and in 2012, and the extreme temperature showed a downward trend from 1998 to 2012, which better responded to the phenomenon of global warming hiatus. The increasing trend of mean temperature in the gully region, the rocky mountain region and the valley plain region was more obvious than that in other regions. The stations with large trend of extreme temperature index almost all occurred in the region with large increases of mean temperature. The increases of average temperature in small increments increased the frequency of extreme high temperature event, with the change range of extreme low temperature and its rate being greater than the extreme high temperature. Climate warming on extreme temperature index had a different effect, small changes in the average temperature in the Loess Plateau made the climate transfer towards the direction of more frequent heat.


Assuntos
Mudança Climática , Clima , China , Aquecimento Global , Temperatura
17.
Nat Commun ; 13(1): 5153, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36055986

RESUMO

Seasonal biases (the warm-season contribution) of Holocene mean annual temperature (MAT) reconstructions from geological records were proposed as a possible cause of the mismatch with climate simulated temperature. Here we analyze terrestrial mollusk assemblages that best reflect seasonal signals and provide quantitative MAT and four-season temperature records for northern China during the past 20,000 years. The MAT estimated from the seasonal temperatures of a four-season-mean based on mollusks shows a peak during ~9000-4000 years ago, followed by a cooling trend. In general, the contribution of summer and winter temperature to MAT is significantly greater than that of spring and autumn temperatures. The relative contribution of each season varies over time and corresponds roughly with the seasonal insolation in each season. This independent evidence from mollusk records from the mid-latitudes of East Asia does not support the Holocene long-term warming trend observed in climate simulations and the seasonal bias explanation.


Assuntos
Clima , Moluscos , Animais , Extremo Oriente , Estações do Ano , Temperatura
18.
Nat Commun ; 13(1): 5158, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36055993

RESUMO

The tropical West Pacific hosts the warmest part of the surface ocean and has a considerable impact on the global climate system. Reconstructions of past temperature in this region can elucidate climate connections between the tropics and poles and the sensitivity of tropical temperature to greenhouse forcing. However, existing data are equivocal and reliable information from terrestrial archives is particularly sparse. Here we constrain the magnitude and timing of land temperature change in the tropical West Pacific across the last deglaciation using an exceptionally precise paleothermometer applied to a well-dated stalagmite from Northern Borneo. We show that the cave temperature increased by 4.4 ± 0.3 °C (2 SEM) from the Last Glacial Maximum to the Holocene, amounting to 3.6 ± 0.3 °C (2 SEM) when correcting for sea-level induced cave altitude change. The warming closely follows atmospheric CO2 and Southern Hemisphere warming. This contrasts with hydroclimate, as reflected by drip water δ18O, which responds to Northern Hemisphere cooling events in the form of prominent drying, while temperature was rising. Our results thus show a close response of tropical temperature to greenhouse forcing, independent of shifts in the tropical circulation patterns.


Assuntos
Atmosfera , Clima , Altitude , Temperatura , Água
19.
Nat Commun ; 13(1): 5176, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056010

RESUMO

Atlantic multidecadal variability is a coherent mode of natural climate variability occurring in the North Atlantic Ocean, with strong impacts on human societies and ecosystems worldwide. However, its periodicity and drivers are widely debated due to the short temporal extent of instrumental observations and competing effects of both internal and external climate factors acting on North Atlantic surface temperature variability. Here, we use a paleoclimate database and an advanced statistical framework to generate, evaluate, and compare 312 reconstructions of the Atlantic multidecadal variability over the past millennium, based on different indices and regression methods. From this process, the best reconstruction is obtained with the random forest method, and its robustness is checked using climate model outputs and independent oceanic paleoclimate data. This reconstruction shows that memory in variations of Atlantic multidecadal variability have strongly increased recently-a potential early warning signal for the approach of a North Atlantic tipping point.


Assuntos
Clima , Ecossistema , Oceano Atlântico , Humanos , Oceanos e Mares , Temperatura
20.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2347-2355, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36131649

RESUMO

We established 340-year chronologies of total ring width, early wood width, and late wood width with tree-ring samples of Pinus taiwanensis at high altitude collected from the western Tianmu Mountain in northern Zhejiang Province. According to the criterion that subsample signal strength (SSS) should be larger than 0.8, the reliable period was from 1810 to 2019. Through the correlation analysis between chronologies and climatic factors, we examined the responses of tree ring growth to climate. The results showed that radial growth of P. taiwanensis was more sensitive to temperature than to precipitation. Comprehensively considering the correlation analysis results for the raw and first-order difference series, early wood width was significantly correlated with the early growing season mean and maximum temperatures of the prior year, while late wood width with prior May and current September mean and maximum temperatures. The correlation pattern of total ring width was similar to that of early wood width, although at a low level. The optimal correlation was between early wood width and prior April-July mean temperature. Based on this relationship, April-July mean temperature of the Tianmu Mountain, East China was reconstructed for the period of 1809-2018 with an explained variance of 61.5%. Both the raw and first-order difference series passed the split sample calibration-verification test. The warm periods were 1809-1833 and 1965-2018, with a cold period in 1834-1964. Temperature had risen rapidly since the 1960s. From the standpoint of low frequency, it reached an unprecedented level since the 1980s over the past 210 years. Spatial correlation analysis showed that the reconstructed temperature series could represent temperature variations of East China, which had a good agreement with a reconstructed regional temperature series from East China. Our results showed that P. taiwanensis had a great potential for paleoclimate reconstruction in East China.


Assuntos
Pinus , Árvores , China , Clima , Temperatura
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