Search

Subseasonal-to-seasonal (S2S) precipitation prediction in boreal spring and summer months, which contains a significant number of high-signal events, is scientifically challenging and prediction skill has remained poor for years. Tibetan Plateau (TP) spring observed surface ­temperatures show a lag correlation with summer precipitation in several remote regions, but current global land–atmosphere coupled models are unable to represent this behavior due to significant errors in producing observed TP surface temperatures. To address these issues, the Global Energy and Water Exchanges (GEWEX) program launched the “Impact of Initialized Land Temperature and Snowpack on Subseasonal-to-Seasonal Prediction” (LS4P) initiative as a community effort to test the impact of land temperature in high-mountain regions on S2S prediction by climate models: more than 40 institutions worldwide are participating in this project. After using an innovative new land state initialization approach based on observed surface 2-m temperature over the TP in the LS4P experiment, results from a multimodel ensemble provide evidence for a causal relationship in the observed association between the Plateau spring land temperature and summer precipitation over several regions across the world through teleconnections. The influence is underscored by an out-of-phase oscillation between the TP and Rocky Mountain surface temperatures. This study reveals for the first time that high-mountain land temperature could be a substantial source of S2S precipitation predictability, and its effect is probably as large as ocean surface temperature over global “hotspot” regions identified here; the ensemble means in some “hotspots” produce more than 40% of the observed anomalies. This LS4P approach should stimulate more follow-on explorations.

This study presents novel insight into the mechanisms of Atlantic Meridional Overturning Circulation (AMOC) reduction and its recovery under a warmer climate scenario. An one-thousand-year-long numerical simulation of a global coupled ocean-ice-atmosphere climate model, subjected to a stationary atmospheric radiative forcing, depict a coherent picture of the Arctic sea ice melting as a trigger for the initial AMOC reduction, along with decreases in the northward fluxes of salt and heat. Further atmospheric-driven ocean processes contribute to an erosion of the stable stratification of the fresher, yet colder waters in the surface layers of the North Atlantic, contributing to the recovery of a permanently altered AMOC.

An expressive number of scientific publications including the recent IPCC-AR6 report have warned about the effects of the ongoing and the projected climate change in the northern high latitudes as response to CO2 forcing. Here we investigate the response of the Arctic region to an increase in atmospheric CO2 concentration using the Brazilian Earth System Model (BESM-OA2.5) and other three state-of-the-art Global Climate Model from the CMIP5 project. We evaluated the Arctic climate sensitivity through the Polar amplification using two numerical experiments: (i) piControl numerical experiment and (ii) abrupt 4xCO2. Our results showed that the northern high latitudes are described as the most climatically sensitive areas of the world, with strongest warming occurring in winter (DJF) and autumn (SON). The Arctic climate sensitivity is linked to changes in sea ice extent and sea ice thickness. Considering this scenario, it is expected that the Arctic will become ice-free in summer time and covered only by first-year-sea ice in the remaining months. We suggest that the projected sea ice albedo feedback will reinforce the Arctic warming with lack of understanding effects beyond the Arctic region.

BackgroundMatch analysis has evolved exponentially over the past decades in team sports resulting in a significant number of published systematic reviews and meta-analyses. An umbrella review of the available literature is needed to provide an integrated overview of current knowledge and contribute to more robust theoretical explanations of team performance.MethodsThe Web of Science (all databases), PubMed, Cochrane Library (Cochrane Database of Systematic Reviews), Scopus, and SPORTDiscus databases were searched for relevant publications prior to 19 February 2021. Appraisal of the methodological quality of included articles was undertaken using the tool for Assessing the Methodological Quality of Systematic Reviews (AMSTAR-2). Twenty-four studies were reviewed that met the following criteria: (1) contained relevant data from match analyses in team ball sports; (2) were defined as systematic reviews or/and meta-analyses; and (3) were written in the English language.ResultsThe overall methodological quality of the 24 included reviews, obtained through the AMSTAR-2, revealed very low confidence ratings (Critically Low,n = 12) for the results of most systematic reviews of match analyses in team ball sports. Additionally, the results showed that research is focused mainly on four levels of analysis: (1) dyadic (microlevel); (2) individual (molecular level; predominant); (3) group (mesolevel), and (4) team dynamics (macrolevel). These levels of analysis included tactical, technical, physical, and psychosocial variables. Team performance was contextualized at two levels, with reference to: (1) match context (e.g. match status, match location, match period, quality of opposition) and (2) sociodemographic and environmental constraints (sex, age groups, competitive level, altitude, temperature, pitch surface).ConclusionsThe evolution of methods for match analysis in team ball sports indicates that: (1) an individual-level performance analysis was predominant; (2) the focus on intermediate levels of analysis, observing performance in dyadic and group interactions, has received less attention from researchers; (3) neglected areas of research include psychosocial aspects of team sports and women’s performance; and (4) analyses of match contexts need greater depth.Registration: The protocol was registered in the International Platform of Registered Systematic Review and Meta-Analysis Protocols with the number 202080067 and the DOI numberhttps://doi.org/10.37766/inplasy2020.8.0067.

The numerical climate simulations from the Brazilian Earth System Model (BESM) are used here to investigate the response of the polar regions to a forced increase in CO2 (Abrupt-4×CO2) and compared with Coupled Model Intercomparison Project phase 5 (CMIP5) and 6 (CMIP6) simulations. The main objective here is to investigate the seasonality of the surface and vertical warming as well as the coupled processes underlying the polar amplification, such as changes in sea ice cover. Polar regions are described as the most climatically sensitive areas of the globe, with an enhanced warming occurring during the cold seasons. The asymmetry between the two poles is related to the thermal inertia and the coupled ocean–atmosphere processes involved. While at the northern high latitudes the amplified warming signal is associated with a positive snow– and sea ice–albedo feedback, for southern high latitudes the warming is related to a combination of ozone depletion and changes in the wind pattern. The numerical experiments conducted here demonstrated very clear evidence of seasonality in the polar amplification response as well as linkage with sea ice changes. In winter, for the northern high latitudes (southern high latitudes), the range of simulated polar warming varied from 10 to 39 K (−0.5 to 13 K). In summer, for northern high latitudes (southern high latitudes), the simulated warming varies from 0 to 23 K (0.5 to 14 K). The vertical profiles of air temperature indicated stronger warming at the surface, particularly for the Arctic region, suggesting that the albedo–sea ice feedback overlaps with the warming caused by meridional transport of heat in the atmosphere. The latitude of the maximum warming was inversely correlated with changes in the sea ice within the model's control run. Three climate models were identified as having high polar amplification for the Arctic cold season (DJF): IPSL-CM6A-LR (CMIP6), HadGEM2-ES (CMIP5) and CanESM5 (CMIP6). For the Antarctic, in the cold season (JJA), the climate models identified as having high polar amplification were IPSL-CM6A-LR (CMIP6), CanESM5(CMIP6) and FGOALS-s2 (CMIP5). The large decrease in sea ice concentration is more evident in models with great polar amplification and for the same range of latitude (75–90∘ N). Also, we found, for models with enhanced warming, expressive changes in the sea ice annual amplitude with outstanding ice-free conditions from May to December (EC-Earth3-Veg) and June to December (HadGEM2-ES). We suggest that the large bias found among models can be related to the differences in each model to represent the feedback process and also as a consequence of each distinct sea ice initial condition. The polar amplification phenomenon has been observed previously and is expected to become stronger in the coming decades. The consequences for the atmospheric and ocean circulation are still subject to intense debate in the scientific community.

The Brazilian Earth System Model (BESM-OA2.5), while simulating the historical period proposed by the fifth phase of the Coupled Model Intercomparison Project (CMIP5), detects an increasing trend in the sea surface height (SSH) on the southern hemisphere oceans relative to that of the pre-industrial era. The increasing trend is accentuated in the CMIP5 RCP4.5 and RCP8.5 future scenarios with higher concentrations of greenhouse gases in the atmosphere. This study sheds light on the sources of such trends in these regions. The results suggest an association with the thermal expansion of the oceans in the upper 700 m due to a gradual warming inflicted by those future scenarios. BESM-OA2.5 presents a surface height increase of 0.11 m in the historical period of 1850–2005. Concerning future projections, BESM-OA2.5 projects SSH increases of 0.14 and 0.23 m (relative to the historical 2005 value) for RCP4.5 and RCP8.5, respectively, by the end of 2100. These increases are predominantly in a band of latitude within 35–60°S in the Atlantic and Indian oceans. The reproducibility of the trend signal detected in the BESM-OA2.5 simulations is confirmed by the results of three other CMIP5 models.

We used climate models to assess the effects of 2 distinct anthropogenic forcings on the water budget in the Amazon basin: (1) increasing global greenhouse gases under the RCP8.5 scenario, and (2) land cover change caused by deforestation. The Eta regional climate model, driven by the Brazilian Earth System Model version 2.5 (BESM 2.5), was used to simulate the climate response under the RCP8.5 scenario and due to deforestation throughout the 21st century. Changes in energy and water budgets led to an increase in temperature that reached 5°C throughout the basin. In the RCP8.5 scenario, moisture convergence, precipitation and evapotranspiration all decreased. In this scenario, the positive feedback mechanism was predominant, as the reductions in evapotranspiration and moisture convergence acted in the same direction to reduce precipitation. In the future deforestation scenarios, reductions in precipitation were even stronger. In this case, the negative feedback mechanism predominated, in which the relative reduction in evapotranspiration was greater than the reduction in precipitation, leading to an increase in moisture convergence over the region. Changes in temperature and the water cycle were intensified in the future deforestation scenarios. These results show that the 2 anthropogenic factors can change the water budget and cause an imbalance in the climate-biome system in the Amazon basin, highlighting the need for public conservation policies to halt the increase in environmental degradation in the Amazon basin and to reduce greenhouse gases emissions due the burning of fossil fuels.

In this work, we report the ongoing implementation of online-coupled aerosol–cloud microphysical–radiation interactions in the Brazilian global atmospheric model (BAM) and evaluate the initial results, using remote-sensing data for JFM 2014 and JAS 2019. Rather than developing a new aerosol model, which incurs significant overheads in terms of fundamental research and workforce, a simplified aerosol module from a preexisting global aerosol–chemistry–climate model is adopted. The aerosol module is based on a modal representation and comprises a suite of aerosol microphysical processes. Mass and number mixing ratios, along with dry and wet radii, are predicted for black carbon, particulate organic matter, secondary organic aerosols, sulfate, dust, and sea salt aerosols. The module is extended further to include physically based parameterization for aerosol activation, vertical mixing, ice nucleation, and radiative optical properties computations. The simulated spatial patterns of surface mass and number concentrations are similar to those of other studies. The global means of simulated shortwave and longwave cloud radiative forcing are comparable with observations with normalized mean biases ≤11% and ≤30%, respectively. Large positive bias in BAM control simulation is enhanced with the inclusion of aerosols, resulting in strong overprediction of cloud optical properties. Simulated aerosol optical depths over biomass burning regions are moderately comparable. A case study simulating an intense biomass burning episode in the Amazon is able to reproduce the transport of smoke plumes towards the southeast, thus showing a potential for improved forecasts subject to using near-real-time remote-sensing fire products and a fire emission model. Here, we rely completely on remote-sensing data for the present evaluation and restrain from comparing our results with previous results until a complete representation of the aerosol lifecycle is implemented. A further step is to incorporate dry deposition, in-cloud and below-cloud scavenging, sedimentation, the sulfur cycle, and the treatment of fires.

The achievement of good productivity and quality of fruits is directly associated with a balanced fertilization, in which phosphate fertilizers have an important role in the agricultural production system. In this context, this work aimed to evaluate the effect of doses of monoammonium phosphate in ground fertilization and associated with the topdressing in the production of the Formosa “Tainung-01” papaya. The experimental design was in complete randomized blocks, in an split plots outline, having as main factor four fertilizer doses in ground fertilization (0; 80; 160, and 250 kg ha-1 of monoammonium phosphate [MAP]) and, as a sub-portion, two fertilizers in topdressing (20 kg ha-1 of Cosmofert® + 45 kg ha-1 of MAP” and “90 kg ha-1 of MAP). The harvesting began in the eighth month and extended until the 12th month after transplanting of the seedlings. All fruits of five plants per experimental unit were collected and classified. The number of fruits, the production per plant, the yield, and the percentage of marketable fruits were evaluated. The ground fertilization with the monoammonium phosphate did not influence the production of Formosa 'Tainung-01' papaya fruits exclusively destined to the domestic market. When the production is destined to the external market, a dosage of 74.0 kg ha-1 of monoammonium phosphate can be used in ground fertilization.

Purpose This study aims to exploit the abundance of solar energy resources for socioeconomic development in the semi -arid Northeastern Brazil as a potent adaptation tool to global climate change. It points out a set of conjuncture factors that allow us to foresee a new paradigm of sustainable development for the region by transforming the sun’s radiant energy into electricity through distributed photovoltaic generation. The new paradigm, as presented in this essay, has the transformative potential to free the region from past regional development dogma, which was dependent on the scarce water resource, and the marginal and predatory use of its Caatinga Biome. Design/methodology/approach The research uses a pre ante design, following the procedures of scenario building, as an adaptation mechanism to climate change in the sector of energy generation and socioeconomic inclusion. Findings The scenarios of socioeconomic resilience to climate change based on the abundance of solar radiation, rather than the scarcity of water, demonstrates its potential as a global adaptation paradigm to climate change. Research limitations/implications The developments proposed are dependent on federal legislation changes, allowing the small producer to be remunerated by the energy produced. Practical implications The proposed smart grid photovoltaic generation program increases the country's resiliency to the effect of droughts and climate change. Social implications As proposed, the program allows for the reversion of a pattern of long term poverty in semi-arid Northeast Brazil. Originality/value The exploitation of the characteristics of abundance of the semiarid climate, i.e. its very condition of semi-aridity with abundant solar radiation, is itself an advantage factor toward adaption to unforeseen drought events. Extensive previous research has focused on weighting and monitoring drought i.e. the paradigm of scarcity. The interplay between exploiting Northeast Brazil’s abundant factors and climate change adaptation, especially at the small farmer levels constitutes a discovery never before contemplated.

Here we respond to Jaramillo et al.’s recent critique of condensation-induced atmospheric dynamics (CIAD). We show that CIAD is consistent with Newton’s laws while Jaramillo et al.’s analysis is invalid. To address implied objections, we explain our different formulations of “evaporative force.” The essential concept of CIAD is condensation’s role in powering atmospheric circulation. We briefly highlight why this concept is necessary and useful.

Coastal ocean observing and modeling systems (coastal observatories), connected with regional and global ocean systems, improve the quality of information and forecasts for effective management of safe and sustainable maritime activities. The public availability of systematic and long-term information of the ocean is an engine for the Blue Economy, boosting economic growth, employment, and innovation. An overview of some Brazilian initiatives is presented in this paper, involving universities, private companies, federal and state agencies, covering institutions from south to north of Brazil. Although these initiatives focus mainly on ocean physics, integrated efforts can extend the scope to include biogeochemistry and marine biodiversity, helping to address interdisciplinary problems. Existing initiatives can be connected, and new ones fostered, to fill in the gaps of temporal and spatial coverage of ocean monitoring in the vast oceanic area under Brazilian jurisdiction (nationally referred to as the Blue Amazon, in reference to the similar richness of the Amazon Forest). The alignment among national and regional initiatives, as well as with international programs, can be promoted if coordinated by a national-level organization, maximizing the return of public investment and socioeconomic benefits. In light of international examples, possible future institutional arrangements are discussed, leveraging from existing national public policies and international cooperation that Brazil is taking part. The United Nations Decade of Ocean Science for Sustainable Development is a timely opportunity to encourage an institutional arrangement to support and articulate an integrated network of coastal observatories in Brazil.

Here we introduce a new tool, the Spectral Diagram (SD), for the comparison of time series in the frequency domain. The SD provides a novel way to display the coherence function, power, amplitude, phase, and skill score of discrete frequencies of two time series. Each SD summarises these quantities in a single plot for multiple targeted frequencies. The versatility of SDs is demonstrated through a series of sea-level comparisons between observations from tide gauges and the model results from a global eddy-permitting ocean general circulation model (MOM5) with explicit tidal forcing. Phase information for the eight principal lunisolar constituents (M2, S2, N2, K2, K1, O1, P1, Q1) is added to the default configuration of MOM5. Inaccurate estimation of phase information is an important source of barotropic errors in ocean modelling, thereby compromising the skill scores in regions where amplitudes are close to the tidal gauge datasets. The greatest contribution of SD analysis is the indication that some diurnal estimates can be improved by adjusting the phase lag in the model as severe underestimation of semidiurnal amplitudes is the main reason for lower skill scores despite higher coherence. Although the SD has been designed for tidal analysis, it is a powerful tool for detecting co-oscillating patterns in multi-scale analyses, and this approach might provide guidance in devising skill scores for inter-comparing model results.

Este volume pretende constituir-se como um espaço de debate sobre temas centrais à formação de professores, debatendo temas relativos à supervisão pedagógica e à importância que essa supervisão tem para a construção de uma profissionalidade docente. Mais do que encontrar receitas para a formação de professores, pretendemos suscitar o debate e proporcionar um espaço de reflexão sobre temas centrais da formação de professores para o século XXI. Os textos - da autoria de um leque de especialistas em ciências da educação e supervisão pedagógica, associados a um vasto conjunto de instituições de ensino superior do país – articulam-se em torno de três eixos de análise: i) Supervisão pedagógica e desenvolvimento profissional docente; ii) Ética e profissionalidade na formação inicial de professores e, iii) Supervisão na formação inicial de professores.

High ozone (O3) concentrations are a major concern about air quality in the Sao Paulo Metropolitan Area (SPMA). During 2016, the 8-hour state standard of 140 µg m–3 was exceeded on 32 days, whereas the 1-hour national standard of 160 µg m–3 was exceeded on 76 days. Exposure to such unhealthy O3 levels and other pollutants can lead to respiratory disease. The focus of this study is to determine the main O3 precursor in terms of the volatile organic compounds (VOCs) in order to provide a scientific basis for controlling this pollutant. In this work, 66 samples of hydrocarbons, 62 of aldehydes and 42 of ethanol were taken during the period from September 2011 to August 2012 from 7:00 to 9:00 a.m. The OZIPR trajectory model and SAPRC atmospheric chemical mechanism were used to determine the major O3 precursors. During the studied period, aldehydes represented 35.3% of the VOCs, followed by ethanol (22.6%), aromatic compounds (15.7%), alkanes (13.5%), ketones (6.8%), alkenes (6.0%) and alkadienes (less than 0.1%). Considering the concentration of VOCs and their typical reactivity, the simulation results showed that acetaldehyde contributed 61.2% of the O3 formation. The total aldehydes contributed 74%, followed by aromatics (14.5%), alkenes (10.2%), alkanes (1.3%) and alkadienes (e.g., isoprene; 0.03%). Simulation results for the SPMA showed that the most effective alternative for limiting the O3 levels was reducing the VOC emissions, mainly the aldehydes.

The accurate representation of the impacts of natural and anthropogenic aerosols in the climate system presents a challenge in General Circulation Models. This paper analyzes the performance of the aerosol component of two Atmospheric General Circulation Models (AGCM): the Europe Centre Hamburg Model - Hamburg Aerosol Model (ECHAM-HAM), and the Community Atmosphere Model - Modal Aerosol Model (CAM5-MAM3) and their comparison with aerosol observations. We analyzed the spatial distribution of aerosols over Brazil represented in terms of the aerosol optical depth (AOD) simulated by these models. The model results are compared to measurements from Aerosol Robotic Network (AERONET) ground station, and satellite observations provided by the Moderate Resolution Imaging Spectroradiometer (MODIS). While both the models provide AODs at 550 nm, only HAM provides the Angstrom exponent that is compared with AERONET measurements. The comparison between the model simulations and the satellite observations of AOD show that the models can reproduce the spatial and temporal distributions, however models underestimate AOD for the four cities and for almost every South American continent during all seasons. During the dry season, characterized by intense biomass burning, CAM5-MAM3 shows inconsistent, but comparatively better results that ECHAM-HAM, with negative biases over Northern and Northeastern regions of Brazil. The Angstrom parameter is reasonably reproduced by ECHAM-HAM, except for Cuiaba, indicating that the particle size distribution is correctly represented in most cities.

A propagação assexuada das Spondias pelo método de estaquia apresenta fortes limitações, não dispondo de tecnologias para a produção comercial de mudas, principalmente quanto ao uso de enraizadores e substratos que potencialize seu desenvolvimento. Diante disso, o objetivo deste trabalho foi avaliar o enraizamento de estacas de cajaraneira sob doses de ácido indolbutírico (AIB) e em diferentes substratos. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 3 × 5, três substratos (comercial - tropstrato; solo+esterco bovino [1v:1v]; esterco bovino+esterco de galinha [1v:1v]) e com cinco concentrações de AIB (0, 600, 1.200, 1.800 e 2.400 mg L-1), usando quatro repetições e 10 estacas por unidade experimental. Aos 115 dias após a montagem do experimento, foram avaliados: número de folhas, de folíolos, de brotos e de raízes; comprimento do broto, das folhas e da raiz; diâmetro do broto; número e comprimento de raízes; porcentagens de estacas calejadas, estacas vivas, estacas brotadas com raiz e estacas brotadas; massa seca das folhas (g), dos brotos (g), das raízes (g) e total (g). Diante dos resultados, observou-se que o regulador de crescimento (AIB) não influenciou o enraizamento de estacas lenhosas de cajaraneira e que o substrato comercial tropstrato proporcionou maior enraizamento de estacas, seguido do substrato solo+esterco bovino (1v:1v). O substrato esterco bovino+esterco de galinha (1v:1v) mostrou-se inadequado para a produção de mudas de cajaraneira propagadas por estaquia.

The numerical climate simulation from Brazilian Earth System Model (BESM) are used here to investigate the response of Polar Regions to a forced increase of CO2 (Abrupt-4xCO2) and compared with Coupled Model Intercomparison Project 5 (CMIP5) simulations. Polar Regions are described as the most climatically sensitive areas of the globe, with an enhanced warming occurring during the cold seasons. The asymmetry between the two poles is related to the thermal inertia and the coupled ocean atmosphere processes involved. While in the northern high latitudes the amplified warming signal is associated to a positive snow and sea ice albedo feedback, for southern high latitudes the warming is related to a combination of ozone depletion and changes in the winds pattern. The numerical experiments conducted here demonstrated a very clear evidence of seasonality in the polar amplification response. In winter, for the northern high latitudes (southern high latitudes) the range of simulated polar warming varied from 15 K to 30 K (2.6 K to 10 K). In summer, for northern high latitudes (southern high latitudes) the simulated warming varies from 3 K to 15 K (3 K to 7 K). The vertical profiles of air temperature indicated stronger warming at surface, particularly for the Arctic region, suggesting that the albedo-sea ice feedback overlaps with the warming caused by meridional transport of heat in atmosphere. The latitude of the maximum warming was inversely correlated with changes in the sea ice within the model’s control run. Three climate models were identified as having high polar amplification for cold season in both poles: MIROC-ESM, BESM-OA V2.5 and GFDL-ESM2M. We suggest that the large BIAS found between models can be related to the differences in each model to represent the feedback process and also as a consequence of the distinct sea ice initial conditions of each model. The polar amplification phenomenon has been observed previously and is expected to become stronger in coming decades. The consequences for the atmospheric and ocean circulation are still subject to intense debate in the scientific community.

This article describes the main features of the Brazilian Global Atmospheric Model (BAM), analyses of its performance for tropical rainfall forecasting, and its sensitivity to convective scheme and horizontal resolution. BAM is the new global atmospheric model of the Center for Weather Forecasting and Climate Research [Centro de Previsão de Tempo e Estudos Climáticos (CPTEC)], which includes a new dynamical core and state-of-the-art parameterization schemes. BAM’s dynamical core incorporates a monotonic two-time-level semi-Lagrangian scheme, which is carried out completely on the model grid for the tridimensional transport of moisture, microphysical prognostic variables, and tracers. The performance of the quantitative precipitation forecasts (QPFs) from two convective schemes, the Grell–Dévényi (GD) scheme and its modified version (GDM), and two different horizontal resolutions are evaluated against the daily TRMM Multisatellite Precipitation Analysis over different tropical regions. Three main results are 1) the QPF skill was improved substantially with GDM in comparison to GD; 2) the increase in the horizontal resolution without any ad hoc tuning improves the variance of precipitation over continents with complex orography, such as Africa and South America, whereas over oceans there are no significant differences; and 3) the systematic errors (dry or wet biases) remain virtually unchanged for 5-day forecasts. Despite improvements in the tropical precipitation forecasts, especially over southeastern Brazil, dry biases over the Amazon and La Plata remain in BAM. Improving the precipitation forecasts over these regions remains a challenge for the future development of the model to be used not only for numerical weather prediction over South America but also for global climate simulations.

*Autor correspondente 1 Unidade Academica de Ciencias Agrarias, CCTA/UFCG, Caixa Postal 1770, CEP 58840-000, Pombal (PB); fernanda_boka24@hotmail.com; fhppereira@hotmail.com; fernandanunes.araujo27@gmail.com. 2 Departamento de Ciencias Ambientais e Tecnologicas, UFERSA, Caixa Postal 137, CEP 59625-900, Mossoro (RN); vanies-agronomia@hotmail.com. 3 Departamento de Ciencias Vegetais, UFERSA, Caixa Postal 137, CEP 59625-900, Mossoro (RN); emanuelappaiva@hotmail.com; joaopaulonobre@yahoo.com.br

Important international reports and a significant number of scientific publications have reported on the abrupt decline of Arctic sea ice and its impact on the Global Climate System. In this paper, we evaluated the ability of the newly implemented Brazilian Earth System Model (BESM-OA) to represent Arctic sea ice and sensitivity to CO2 forcing, using decadal simulations (1980-2012) and future scenarios (2006-2100). We validated our results with satellite observations and compared them to Coupled Model Intercomparison Project, Phase 5 (CMIP5) for the same numerical experiment. BESM results for the seasonal cycle are consistent with CMIP5 models and observations. However, almost all models tend to overestimate sea ice extent in March compared to observations. The correct evaluation of minimum record of sea ice, in terms of time, spatial and area remains a limitation in Coupled Global Climate Models. Looking to spatial patterns, we found a systematic model error in September sea ice cover between the Beaufort Sea and East Siberia for most models. Future scenarios show a decrease in sea ice extent in response to an increase in radiative forcing for all models. From the year 2045 onwards, all models show a dramatic shrinking in sea ice and ice free conditions at the end of the melting season. The projected future sea ice loss is explained by the combined effects of the amplified warming in northern hemisphere high latitudes and feedbacks processes.

During the Younger Dryas (YD), paleoceanographic proxies indicate a weakening of the Atlantic Meridional Overturning Circulation (AMOC) resulting in a widespread surface cooling of the North Atlantic and a southward displacement of the Intertropical Convergence Zone (ITCZ). In the western tropical Atlantic, competing ocean and atmospheric processes may result in contrasting surface hydrography scenarios north and south of the equator during the YD. Based on new and compiled data, we provide an up-to-date model-data comparison of changes in western tropical Atlantic surface hydrography during the YD. We show that both transient model simulations and proxy results indicate warming of sea surface temperatures (SST) in the western tropical South Atlantic, but disagree for the SST in the western tropical North Atlantic. Proxies also reveal a complex spatial pattern in surface salinity in the western tropical Atlantic, while a broad negative anomaly is observed in the model output. By comparing planktonic foraminiferal Ba/Ca records from different records in the western tropical Atlantic we constrain ITCZ shifts from the YD to the early Holocene. Based on the Ba/Ca records, the ITCZ reached its southernmost position between 13 and 11.8 ka and started to move northward reaching its northernmost position between 10.8 and 9.7 ka.

Important features of the Atlantic meridional mode (AMM) are not fully understood. We still do not know what determines its dominant decadal variability or the complex physical processes that sustain it. Using reanalysis datasets, we investigated the influence of the North Atlantic Ocean variability on the dominant decadal periodicity that characterizes the AMM. Statistical analyses demonstrated that the correlation between the sea surface temperature decadal variability in the Atlantic Ocean and the AMM time series characterizes the Atlantic multidecadal oscillation (AMO). This corroborates previous studies that demonstrated that the AMO precedes the AMM. A causal inference with a newly developed rigorous and quantitative causality analysis indicates that the AMO causes the AMM. To further understand the influence of the subsurface ocean on the AMM, the relationship between the ocean heat content (0&ndash, 300 m) decadal variability and AMM was analyzed. The results show that although there is a significant zero-lag correlation between the ocean heat content in some regions of the North Atlantic (south of Greenland and in the eastern part of the North Atlantic) and the AMM, their cause-effect relationship on decadal time scales is unlikely. By correlating the AMO with the ocean heat content (0&ndash, 300 m) decadal variability, the former precedes the latter, however, the causality analysis shows that the ocean heat content variability drives the AMO, corroborating several studies that point out the dominant role of the ocean heat transport convergence on AMO.

Amburana cearensis, conhecida como cumaru, é uma espécie presente em todo bioma caatinga, sendo recomendada para recuperação de áreas degradadas e usos fitoterápicos. O objetivo do presente trabalho foi determinar os níveis de tolerância ao estresse hídrico na germinação e no crescimento de plântulas de cumaru em função da massa das sementes. Inicialmente as sementes foram pesadas e separadas em três classes (leves, médias e pesadas), sendo estas submetidas ao estresse hídrico, utilizando soluções de Polietilenoglicol 6000, em diferentes potenciais (0,0; -0,2; -0,4; - 0,6; -0,8 e -1,0 MPa) e colocadas para germinar na temperatura de 30 °C em câmaras de germinação. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3 x 6 (classes de massa x potencial hídrico). Para a avaliação da germinação, foram determinados a primeira contagem, porcentagem final e índice de velocidade de germinação, enquanto para a avaliação do crescimento das plântulas determinou-se o comprimento e massa seca do epicótilo e do eixo raiz + hipocótilo e a razão parte aérea/raiz. Os dados foram submetidos ao teste de normalidade e quando se apresentaram normais, realizou-se análise de variância, comparação de médias e regressão. O decréscimo do potencial hídrico prejudica a germinação e o crescimento de plântulas oriundas de sementes médias e pesadas em relação às leves, sendo a partir do potencial -0,6 MPa uma condição estritamente limitante na formação de plântulas normais de A. cearensis. Amburana cearensis, known locally as Cumaru, is a species found throughout the caatinga biome, being recommended in the reclamation of degraded areas and for use in phytotherapy. The aim of the present work was to determine the levels of tolerance to water stress at germination and on seedling growth in seedlings of the cumaru, as a function of seed weight. The seeds were initially weighed and separated into three classes (light, medium and heavy), then subjected to water stress using solutions of polyethylene glycol 6000 at different potentials (0.0, -0.2, -0.4, -0.6, -0.8 and -1.0 MPa) and left to germinate at 30 °C in germination chambers. The experimental design was a completely randomised 3 x 6 factorial scheme (weight class x water potential). To evaluate germination, first count, final percentage and rate of germination index were determined, while to evaluate seedling growth, the length and dry weight of the epicotyl and of the root axis plus hypocotyl, and the shoot to root ratio were all determined. Data were tested for normality, and if normal, variance analysis, means comparison and regression were carried out. A decrease in water potential impairs the germination and growth of seedlings derived from medium and heavy seeds in relation to light seeds, with potentials of -0.6 MPa or more strictly limiting the formation of normal seedlings of A. cearensis.

The tetrazolium test is a quick and effective method for evaluating viability in seeds. The aim of this study was to determine a methodology for using the tetrazolium test, and its efficiency in verifying viability in seeds of the gherkin (Cucumis anguria L.). Consequently, five batches of gherkin seed were initially evaluated by the tests for germination, first count and speed of germination. The batches were then subjected to treatments in order to adjust the methodology for the tetrazolium test, evaluating three concentrations of tetrazolium solution (0.100, 0.075 and 0.050%), kept in the dark for two, four and six hours, under temperatures of 35 °C and 40 °C, with four replications of 25 seeds per treatment. At the end of the staining period, the seeds were washed in running water, split lengthways between the cotyledons, and classified as viable and non-viable. Evaluation of viability in seeds of the gherkin by tetrazolium test is efficient when carried out at a concentration of 0.050%, either for six hours at 35 °C or four hours at 40 °C. RESUMO O teste de tetrazólio é um método rápido e eficaz para avaliar a viabilidade das sementes. Este trabalho teve como objetivo determinar a metodologia de execução do teste de tetrazólio e a sua eficiência para verificar a viabilidade em sementes de maxixe (Cucumis anguria L.). Para isso, cinco lotes de sementes de maxixe foram inicialmente avaliados pelo teste de germinação, primeira contagem e velocidade de germinação. Posteriormente os lotes foram submetidos aos tratamentos para adequação da metodologia do teste de tetrazólio, sendo avaliadas três concentrações da solução de tetrazólio (0,100; 0,075 e 0,050%), mantidas no escuro, por duas, quatro e seis horas, sob temperaturas de 35 e 40 °C, com quatro repetições de 25 sementes para cada tratamento. Decorridos os períodos de coloração, as sementes foram lavadas em água corrente, seccionadas longitudinalmente entre os cotilédones e classificados em viáveis e não viáveis. A avaliação da viabilidade de sementes de maxixe pelo teste de tetrazólio é eficiente quando realizada sob concentração de 0,050% por seis horas a 35 °C ou quatro horas a 40 °C.

The use of natural bio-stimulant in the early development of rootstock acerola, along with the use of mycorrhizal association, represents an alternative to supplement the nutritional demands of plants and consequently stimulates the growth of seedlings. Marine algae have been recognized as excellent natural fertilizer and bio-stimulants for plants. Arbuscular mycorrhizal fungi can be used as natural biofertilizers on seedling production. The objective of this study was to evaluate the initial growth and the doses of seaweed (Ascophyllum nodosum) in the production of rootstocks Malpighia emarginata inoculated with the fungus Glomus fasciculatum. The experiment was distributed in a completely randomized design in corresponding to two treatments involving arbuscular mycorrhizal fungi (0.0 and 1.0 g of inoculum per 10 g seed) and four treatments factorial (2 × 4) extract applications involving seaweed (doses 2, 4 and 6 mL L-1) and control (no application), with five replications. Data were subjected to normality test and, when presented normal, there was analysis of variance and comparisons of means and polynomial regression. The use of seaweed at a dose of 6.0 mL L-1 of the extract, together with the association of mycorrhizal fungus Glomus fasciculatum, can provide increased productivity in the nursery and shorter production rootstock acerola

To provide long-term simulations of climate change at higher resolution, Regional Climate Models (RCMs) are nested in global climate models (GCMs). The objective of this work is to evaluate the Eta RCM simulations driven by three global models, the HadGEM2-ES, BESM, and MIROC5, for the present period, 1961-1990. The RCM domain covers South America, Central America, and Caribbean. These simulations will be used for assessment of climate change projections in the region. Maximum temperatures are generally underestimated in the domain, in particular by MIROC5 driven simulations, in summer and winter seasons. Larger spread among the simulations was found in the minimum temperatures, which showed mixed signs of errors. The spatial correlations of temperature simulations against the CRU observations show better agreement for the MIROC5 driven simulations. The nested simulations underestimate precipitation in large areas over the continent in austral summer, whereas in winter overestimate occurs in southern Amazonia, and underestimate in southern Brazil and eastern coast of Northeast Brazil. The annual cycle of the near-surface temperature is underestimated in all model simulations, in all regions in Brazil, and in most of the year. The temperature and precipitation frequency distributions reveal that the RCM and GCM simulations contain more extreme values than the CRU observations. Evaluations of the climatic extreme indicators show that in general hot days, warm nights, and heat waves are increasing in the period, in agreement with observations. The Eta simulations driven by HadGEM2-ES show wet trends in the period, whereas the Eta driven by BESM and by MIROC5 show trends for drier conditions.

The response of the global climate system to atmospheric CO2 concentration increase in time is scrutinized employing the Brazilian Earth System Model Ocean–Atmosphere version 2.3 (BESM-OA2.3). Through the achievement of over 2000 yr of coupled model integrations in ensemble mode, it is shown that the model simulates the signal of recent changes of global climate trends, depicting a steady atmospheric and oceanic temperature increase and corresponding marine ice retreat. The model simulations encompass the time period from 1960 to 2105, following the phase 5 of the Coupled Model Intercomparison Project (CMIP5) protocol. Notwithstanding the accurate reproduction of large-scale ocean–atmosphere coupled phenomena, like the ENSO phenomena over the equatorial Pacific and the interhemispheric gradient mode over the tropical Atlantic, the BESM-OA2.3 coupled model shows systematic errors on sea surface temperature and precipitation that resemble those of other global coupled climate models. Yet, the simulations demonstrate the model’s potential to contribute to the international efforts on global climate change research, sparking interest in global climate change research within the Brazilian climate modeling community, constituting a building block of the Brazilian Framework for Global Climate Change Research.

Summary The coastal zone of northeastern Brazil is characterized by intense human activities and by large settlements and also experiences high soil losses that can contribute to environmental damage. Therefore, it is necessary to build an integrated modeling-forecasting system for rainfall-runoff erosion that assesses plans for water availability and sediment yield that can be conceived and implemented. In this work, we present an evaluation of an integrated modeling system for a basin located in this region with a relatively low predictability of seasonal rainfall and a small area (600 km 2 ). The National Center for Environmental Predictions – NCEP’s Regional Spectral Model (RSM) nested within the Center for Weather Forecasting and Climate Studies – CPTEC’s Atmospheric General Circulation Model (AGCM) were investigated in this study, and both are addressed in the simulation work. The rainfall analysis shows that: (1) the dynamic downscaling carried out by the regional RSM model approximates the frequency distribution of the daily observed data set although errors were detected in the magnitude and timing (anticipation of peaks, for example) at the daily scale, (2) an unbiased precipitation forecast seemed to be essential for use of the results in hydrological models, and (3) the information directly extracted from the global model may also be useful. The simulated runoff and reservoir-stored volumes are strongly linked to rainfall, and their estimation accuracy was significantly improved at the monthly scale, thus rendering the results useful for management purposes. The runoff-erosion forecasting displayed a large sediment yield that was consistent with the predicted rainfall.

Resumen pt: O objetivo do presente trabalho foi estudar o desenvolvimento inicial de dois acessos de mamoeiro (Carica papaya L.) inoculando suas sementes com diferen...

In order to create the necessary scientific knowledge for Brazil to understand and deal with the causes and consequences of climate change, the federal government created, in 2007, the Brazilian Network on Global Climate Change Research (Rede CLIMA). Rede CLIMA needs to discuss issues, pose questions, develop methodologies and technological products, find answers, and suggest solutions that are relevant to society. In its first phase, it focused mainly on providing infrastructure and consolidating the sub-networks. Several scientific advances were also achieved, a selection of which are presented in sections focusing on climate modelling, agriculture, energy and water, human development and mobility, biodiversity and ecosystem services, and human health. Now, in its second phase, the objective is to straighten collaboration between sub-networks by means of interdisciplinary projects. It is argued that in order to succeed the Network needs to foster research whose merit is measured not exclusively by academic production., A fim de criar o conhecimento científico necessário para o Brasil entender e lidar com as causas e consequências das mudanças climáticas, o governo federal criou, em 2007, a Rede Brasileira de Pesquisa em Mudanças Climáticas Globais (Rede CLIMA). A Rede CLIMA precisa discutir questões, fazer perguntas, desenvolver metodologias e produtos tecnológicos, encontrar respostas e sugerir soluções que sejam relevantes para a sociedade. Em sua primeira fase, a Rede concentrou-se em fornecer infraestrutura e consolidar suas sub-redes. Houve também vários avanços científicos, alguns dos quais são apresentados em seções focadas em modelagem climática, agricultura, energia e água, desenvolvimento e mobilidade humana, biodiversidade e serviços dos ecossistemas, e saúde humana. Agora, em sua segunda fase, o objetivo é estabelecer colaborações entre sub-redes por meio de projetos interdisciplinares. Argumenta-se que, para que tenha sucesso, a Rede precisa fomentar pesquisas de longo-prazo cujo mérito não seja medido apenas pela produção acadêmica.

The biogeochemical dynamics of carbon in the ocean is a subject of fundamental interest to environmental studies. In this context, we have implemented a ten year run of the Brazilian Earth System Coupled Ocean-Atmosphere Model (BESM-OA2.3) integrated with TOPAZ biogeochemical model for the Atlantic basin. The modeled ΔpCO2 for the tropical Atlantic shows very clearly a high dominance of positive fluxes, that is, the CO2 fluxes are sea-to-air throughout the tropical region and for both winter and summer periods. In the mid-latitudes regions negatives fluxes (air-to-sea) were observed for both seasons. An exception to this pattern is an extensive negative tongue on the latitude 10N. The occurrence of this negative ΔpCO2 tongue region in the Tropical Atlantic is highly correlated to negative Evaporation-Precipitation values during this season. In the northern hemisphere (NH) summer the negative values of ΔpCO2 in the tropical Atlantic region are concentrated in the adjacent zone of the Amazon river mouth due to the North Equatorial Counter Current intensification. This process favors the formation of a carbon sink in the adjacent region of the Amazon river mouth. Model results show lowest values of dissolved inorganic carbon (DIC) in a surface layer (100 - 150 m). Highest DIC values are observed in deeper layers and concentrated in an equatorial band. The chlorophyll bloom in equatorial zones was well represented by the model. These blooms are the result of equatorial upwelling that brings the high concentration tongues of DIC present in the equatorial band towards the euphotic zone. This is the first published paper about the BESM-OA2.3 integrated with TOPAZ. The presented results suggest that this modeling system is able to reproduce the main regional carbon dynamics features of the mid-latitude/tropical Atlantic.

Resumen pt: O uso da agua de rejeito na agricultura pode ser considerado uma alternativa importante na preservacao dos recursos naturais. Com este objetivo foi insta...

The impact of ocean–atmosphere interactions on summer rainfall over the South Atlantic Ocean is explored through the use of coupled ocean–atmosphere models. The Brazilian Center for Weather Forecast and Climate Studies (CPTEC) coupled ocean–atmosphere general circulation model (CGCM) and its atmospheric general circulation model (AGCM) are used to gauge the role of coupled modes of variability of the climate system over the South Atlantic at seasonal time scales. Twenty-six years of summer [December–February (DJF)] simulations were done with the CGCM in ensemble mode and the AGCM forced with both observed sea surface temperature (SST) and SST generated by the CGCM forecasts to investigate the dynamics/thermodynamics of the two major convergence zones in the tropical Atlantic: the intertropical convergence zone (ITCZ) and the South Atlantic convergence zone (SACZ). The results present both numerical model and observational evidence supporting the hypothesis that the ITCZ is a thermally direct, SST-driven atmospheric circulation, while the SACZ is a thermally indirect atmospheric circulation controlling SST variability underneath—a consequence of ocean–atmosphere interactions not captured by the atmospheric model forced by prescribed ocean temperatures. Six CGCM model results of the Ensemble-based Predictions of Climate Changes and their Impacts (ENSEMBLES) project, NCEP–NCAR reanalysis data, and oceanic and atmospheric data from buoys of the Prediction and Research Moored Array in the Tropical Atlantic (PIRATA) Project over the tropical Atlantic are used to validate CPTEC’s coupled and uncoupled model simulations.

Seasonal prediction is based on changes in the probability of weather statistics due to changes in slowly varying forcings such as sea-surface temperature anomalies, most notably those associated with El Niňo–Southern Oscillation (ENSO). However, seasonal weather can be perturbed by many factors, and is very much influenced by internal variability of the atmosphere, so comprehensive models are needed to identify what can be predicted. The predictability and probabilistic nature of seasonal forecasts is explained with suitable examples. Current capabilities for seasonal prediction that have grown out of work done in the research community at both national and international levels are described. Dynamical seasonal prediction systems are operational or quasi-operational at a number of forecasting centres around the world. Requirements for seasonal prediction include initial conditions, particularly for the upper ocean but also other parts of the climate system; high quality models of the ocean-atmosphere-land system; and data for verification and calibration. The wider context of seasonal prediction and seamless forecasting is explained. Recommendations for the future of seasonal prediction and climate services are given.

The effects of Amazon deforestation on climate change are investigated using twin numerical experiments of an atmospheric general circulation model (AGCM) with prescribed global sea surface temperature and the same AGCM coupled to an ocean GCM (CGCM) over the global tropics. An ensemble approach is adopted, with 10-member ensemble averages of a control simulation compared with perturbed simulations for three scenarios of Amazon deforestation. The latest 20 yr of simulation from each experiment are analyzed. Local surface warming and rainfall reduction are simulated by both models over the Amazon basin. The coupled model presented a rainfall reduction that is nearly 60% larger compared to its control run than those obtained by the AGCM. The results also indicated that both the fraction of the deforested area and the spatial continuity of the vegetated area might be important for modulating global climate variability and change. Additionally, significant remote atmospheric responses to Amazon deforestation scenarios are detected for the coupled simulations, which revealed global ocean and atmosphere circulation changes conducive to enhanced ocean–atmosphere variability over the Pacific Ocean. This, in turn, is interpreted as a manifestation of enhanced El Niño–Southern Oscillation (ENSO) activity over the Pacific and a positive feedback contributing to the extra rainfall reduction over the Amazon on the coupled simulations.

This study investigates long-term climate trends in Pernambuco, Northeast Brazil (Nordeste), and in the Tropical Atlantic islands of Fernando de Noronha and Cape Verde. The study is based on meteorological station time series and model simulations of present and future climates. Past trends are compared with numerical simulations of present and future climate scenarios for the periods of 1960-2000 and 2010-2050. Both the station data analyses and numerical simulations revealed trends of increasing temperature maxima and diminishing precipitation. While station data analyses showed modest warming in Fernando de Noronha they revealed strong warming and drying trends in Cape Verde similar to the trends detected over the semiarid Nordeste. The water-balance calculations for the study sites showed reduced soil moisture availability and total rainfall in all areas. The observed temperature and precipitation trends are indicative that aridification processes are underway in Pernambuco and Cape Verde. The atmospheric model simulations were consistent with the station data regarding the present warming; the climate change scenarios for 2010-2050 indicated a faster increase of daily temperature maxima over Nordeste compared to that simulated for the recent past.

Os testes de germinacao e de vigor sao componentes essenciais do processo de controle de qualidade das empresas produtoras de sementes. Diante disso, nesta pesquisa o objetivo foi estudar a metodologia do teste de condutividade eletrica, verificando sua eficiencia na identificacao de diferentes niveis de vigor de lotes de sementes de coentro. Para tanto, utilizaram-se quatro cultivares (Portugues, Super Verdao, Tabocas e Verdao), cada uma representada por quatro lotes de sementes, que inicialmente foram submetidas as avaliacoes do grau de umidade, germinacao, primeira contagem de germinacao e emergencia de plântulas. O teste de condutividade eletrica foi realizado com 25 e 50 sementes embebidas em 50 e 75 mL de agua destilada, a 25 oC, por 2, 8 e 24 horas. O teste de condutividade eletrica e eficiente para a avaliacao do potencial fisiologico de sementes de coentro quando conduzido com 50 sementes imersas em 50 mL de agua destilada, a 25 oC, apos duas horas de embebicao.

The dynamical basis for seasonal to decadal climate predictions and predictability over South America is reviewed. It is shown that, while global tropical SSTs affect both predictability and predictions over South America, the current lack of SST predictability over the tropical Atlantic represents a limiting factor to seasonal climate predictions over some parts of the continent. The model’s skill varies with the continental region: the highest skill is found in the “Nordeste” region and the lowest skill over southeastern Brazil. It is also suggested that current two-tier approaches to predict seasonal climate variations might represent a major limitation to forecast coupled ocean–atmosphere phenomena like the South Atlantic convergence zone. Also discussed are the possible effects of global climate change on regional predictability of seasonal climate.

Este artigo mostra os resultados de pesquisa para o semiárido pernambucano utilizando séries temporais diárias de temperatura e de precipitação com mais de 40 anos, com cenários futuros de mudanças do clima para o período de 2010 a 2050. Para determinar as tendências de mudanças do clima, presente e futuro, foram utilizadas tendências de mudanças climáticas, resultados de balanço hídrico e saídas do modelo atmosférico regional aninhado ETA, em cenário global do modelo climático aninhado em dois modelos climáticos globais, HadCM3 e BESM. Os resultados indicaram tendência de aumento das temperaturas máximas, redução das temperaturas mínimas, redução da pluviosidade, média anual, indicando tendência à aridização na região.