Critical transitions in the Amazon forest system.

The possibility that the Amazon forest system could soon reach a tipping point, inducing large-scale collapse, has raised global concern1-3. For 65 million years, Amazonian forests remained relatively resilient to climatic variability. Now, the region is increasingly exposed to unprecedented stress from warming temperatures, extreme droughts, deforestation and fires, even in central and remote parts of the system1. Long existing feedbacks between the forest and environmental conditions are being replaced by novel feedbacks that modify ecosystem resilience, increasing the risk of critical transition. Here we analyse existing evidence for five major drivers of water stress on Amazonian forests, as well as potential critical thresholds of those drivers that, if crossed, could trigger local, regional or even biome-wide forest collapse. By combining spatial information on various disturbances, we estimate that by 2050, 10% to 47% of Amazonian forests will be exposed to compounding disturbances that may trigger unexpected ecosystem transitions and potentially exacerbate regional climate change. Using examples of disturbed forests across the Amazon, we identify the three most plausible ecosystem trajectories, involving different feedbacks and environmental conditions. We discuss how the inherent complexity of the Amazon adds uncertainty about future dynamics, but also reveals opportunities for action. Keeping the Amazon forest resilient in the Anthropocene will depend on a combination of local efforts to end deforestation and degradation and to expand restoration, with global efforts to stop greenhouse gas emissions.

AMOC decline and recovery in a warmer climate.

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.

Amazon Biobank: a collaborative genetic database for bioeconomy development.

Biodiversity is proposed as a sustainable alternative for the economic development of high-biodiversity regions. Especially in the field of biodiversity genomics, the development of low-cost DNA sequencing opens an opportunity for new actors beyond academia to engage in genomic sequencing. However, it is challenging to adequately compensate non-academic actors such as local populations for their contribution to the innovation process, preventing better bioeconomy development. Although many repositories register genomic data to support biodiversity research, they do not facilitate the fair sharing of economic benefits. In this work, we propose the creation of the Amazon Biobank, a community-based genetic database. We employed blockchain to build a transparent and verifiable log of transactions involving genomic data, and we used smart contracts to implement an internal monetary system for all participants who collect, insert, process, store, and validate genomic data. We also used peer-to-peer solutions to allow users with commodity computers to collaborate with the storage and distribution of DNA files. By combining emerging technologies, Amazon Biobank provides adequate benefit-sharing among all participants that collaborate with data, knowledge, and computational resources. It also provides traceability and auditability, allowing easy association between biotechnological research and DNA data. In addition, the solution is highly scalable and less dependent on the trust deposited in any system player. Therefore, Amazon Biobank can become an important stepping stone to unlock the potential of bioeconomy in rich ecosystems such as the Amazon Rainforest.

Human impacts outpace natural processes in the Amazon.

Amazonian environments are being degraded by modern industrial and agricultural activities at a pace far above anything previously known, imperiling its vast biodiversity reserves and globally important ecosystem services. The most substantial threats come from regional deforestation, because of export market demands, and global climate change. The Amazon is currently perched to transition rapidly from a largely forested to a nonforested landscape. These changes are happening much too rapidly for Amazonian species, peoples, and ecosystems to respond adaptively. Policies to prevent the worst outcomes are known and must be enacted immediately. We now need political will and leadership to act on this information. To fail the Amazon is to fail the biosphere, and we fail to act at our peril.

Projections of future forest degradation and CO2 emissions for the Brazilian Amazon.

In recent years, the area affected by forest degradation in the Brazilian Amazon has frequently been higher than deforestation. From August 2006 to July 2019, the degraded area totaled 194,058 km2, representing almost two times the 99,630 km2 deforested in the same period. The impacts of degradation include biodiversity loss and changes in the carbon stocks, affecting the CO2 balance and future climate changes. This paper aims to explore socioeconomic and environmental factors that influence forest degradation, project future scenarios, and assess the impact on the regional carbon balance, combining forest degradation and deforestation-related processes (clear-cut deforestation and secondary vegetation dynamics). We show that, while net CO2 emissions from 2020 to 2050 are 0.74 Gt CO2 in the Sustainable scenario, this value reached 22.63 Gt CO2 in the Fragmentation scenario, an increasingly plausible scenario given the recent trends in the region.

Limiting the high impacts of Amazon forest dieback with no-regrets science and policy action.

Large uncertainties still dominate the hypothesis of an abrupt large-scale shift of the Amazon forest caused by climate change [Amazonian forest dieback (AFD)] even though observational evidence shows the forest and regional climate changing. Here, we assess whether mitigation or adaptation action should be taken now, later, or not at all in light of such uncertainties. No action/later action would result in major social impacts that may influence migration to large Amazonian cities through a causal chain of climate change and forest degradation leading to lower river-water levels that affect transportation, food security, and health. Net-present value socioeconomic damage over a 30-year period after AFD is estimated between US dollar (USD) $957 billion (×109) and $3,589 billion (compared with Gross Brazilian Amazon Product of USD $150 billion per year), arising primarily from changes in the provision of ecosystem services. Costs of acting now would be one to two orders of magnitude lower than economic damages. However, while AFD mitigation alternatives-e.g., curbing deforestation-are attainable (USD $64 billion), their efficacy in achieving a forest resilience that prevents AFD is uncertain. Concurrently, a proposed set of 20 adaptation measures is also attainable (USD $122 billion) and could bring benefits even if AFD never occurs. An interdisciplinary research agenda to fill lingering knowledge gaps and constrain the risk of AFD should focus on developing sound experimental and modeling evidence regarding its likelihood, integrated with socioeconomic assessments to anticipate its impacts and evaluate the feasibility and efficacy of mitigation/adaptation options.

Brazilian Scientific Mobility Program - Science without Borders - Preliminary Results and Perspectives.

The Brazilian Scientific Mobility Program - Science without Borders (SwB) - saw the concession of over 101 thousand scholarships for Brazilian STEM students and education professionals to attend universities worldwide. As the first phase of this program ends, it is time to take a first look at its impacts, mainly on the undergraduate student body (79% of total scholarships implemented). Benefits included a 6-month language course (optional), a one year undergraduate course and optional 2 month internship in a university, government laboratory or technology company. Positive impacts have been seen on entrance into post-graduate programs (>20% of SwB students compared to <5% of the overall student body of similar fields), as well as high representation of lower income families (>50% from families with less than 6 minimum wages per month). The impact of the program will need to be evaluated over the next years, but innovation on the part of the students is already apparent. Any new SwB program needs to take into account the lessons learned from this first experience and therefore recommendations are presented.

Brazilian Scientific Mobility Program - Science without Borders - Preliminary Results and Perspectives

ABSTRACT The Brazilian Scientific Mobility Program - Science without Borders (SwB) - saw the concession of over 101 thousand scholarships for Brazilian STEM students and education professionals to attend universities worldwide. As the first phase of this program ends, it is time to take a first look at its impacts, mainly on the undergraduate student body (79% of total scholarships implemented). Benefits included a 6-month language course (optional), a one year undergraduate course and optional 2 month internship in a university, government laboratory or technology company. Positive impacts have been seen on entrance into post-graduate programs (>20% of SwB students compared to <5% of the overall student body of similar fields), as well as high representation of lower income families (>50% from families with less than 6 minimum wages per month). The impact of the program will need to be evaluated over the next years, but innovation on the part of the students is already apparent. Any new SwB program needs to take into account the lessons learned from this first experience and therefore recommendations are presented.

Land-use and climate change risks in the Amazon and the need of a novel sustainable development paradigm.

For half a century, the process of economic integration of the Amazon has been based on intensive use of renewable and nonrenewable natural resources, which has brought significant basin-wide environmental alterations. The rural development in the Amazonia pushed the agricultural frontier swiftly, resulting in widespread land-cover change, but agriculture in the Amazon has been of low productivity and unsustainable. The loss of biodiversity and continued deforestation will lead to high risks of irreversible change of its tropical forests. It has been established by modeling studies that the Amazon may have two "tipping points," namely, temperature increase of 4 °C or deforestation exceeding 40% of the forest area. If transgressed, large-scale "savannization" of mostly southern and eastern Amazon may take place. The region has warmed about 1 °C over the last 60 y, and total deforestation is reaching 20% of the forested area. The recent significant reductions in deforestation-80% reduction in the Brazilian Amazon in the last decade-opens up opportunities for a novel sustainable development paradigm for the future of the Amazon. We argue for a new development paradigm-away from only attempting to reconcile maximizing conservation versus intensification of traditional agriculture and expansion of hydropower capacity-in which we research, develop, and scale a high-tech innovation approach that sees the Amazon as a global public good of biological assets that can enable the creation of innovative high-value products, services, and platforms through combining advanced digital, biological, and material technologies of the Fourth Industrial Revolution in progress.

Variability of carbon and water fluxes following climate extremes over a tropical forest in southwestern Amazonia.

The carbon and water cycles for a southwestern Amazonian forest site were investigated using the longest time series of fluxes of CO2 and water vapor ever reported for this site. The period from 2004 to 2010 included two severe droughts (2005 and 2010) and a flooding year (2009). The effects of such climate extremes were detected in annual sums of fluxes as well as in other components of the carbon and water cycles, such as gross primary production and water use efficiency. Gap-filling and flux-partitioning were applied in order to fill gaps due to missing data, and errors analysis made it possible to infer the uncertainty on the carbon balance. Overall, the site was found to have a net carbon uptake of ≈5 t C ha(-1) year(-1), but the effects of the drought of 2005 were still noticed in 2006, when the climate disturbance caused the site to become a net source of carbon to the atmosphere. Different regions of the Amazon forest might respond differently to climate extremes due to differences in dry season length, annual precipitation, species compositions, albedo and soil type. Longer time series of fluxes measured over several locations are required to better characterize the effects of climate anomalies on the carbon and water balances for the whole Amazon region. Such valuable datasets can also be used to calibrate biogeochemical models and infer on future scenarios of the Amazon forest carbon balance under the influence of climate change.

Modeling the impact of net primary production dynamics on post-disturbance Amazon savannization.

Amazon tropical forests are being replaced by pasturelands and croplands, but they sometimes revert to regrowth forest when abandoned after a period of agricultural use. Research suggests that this secondary regrowth is limited by climate and nutrient availability and, using a coupled biosphere-atmosphere model, we investigated patterns in the regrowth of the Amazon rainforest after a full deforestation event, considering different types of nutrient stress. We found that, over a 50 year regrowth period, the reduction of precipitation caused by large-scale deforestation was not sufficient to prevent secondary forest regrowth, but this decrease in precipitation combined with nutrient limitation, due to logging and frequent fires, did indeed prevent forest regrowth in central and southern Amazonia, leading to a savannization. These results are concerning, as the northern Mato Grosso region has the highest clearing rate in Amazonia. The low resilience of the forest under nutrient stress indicates that a large scale disturbance could greatly expand the area suitable for cropland, accelerating forest disappearance.

Global environmental change research: empowering developing countries.

This paper discusses ways to reconcile the United Nations Millennium Development Goals with environmental sustainability at the national and international levels. The authors argue that development and better use of sustainability relevant knowledge is key, and that this requires capacity building globally, and especially in the less developed regions of the world. Also essential is stronger integration of high-quality knowledge creation and technology--and policy--development, including, importantly, the creation of centers of excellence in developing regions which effectively use and produce applications-directed high quality research and bring it to bear on decision making and practices related to environmental change and sustainable management of natural resources. The authors argue that Southern centers of excellence are a necessary first step for bottom-up societal transformation towards sustainability, and that such centers must help design innovative ways to assess and place value on ecosystem services.

Global environmental change research: empowering developing countries

This paper discusses ways to reconcile the United Nations Millennium Development Goals with environmental sustainability at the national and international levels. The authors argue that development and better use of sustainability relevant knowledge is key, and that this requires capacity building globally, and especially in the less developed regions of the world. Also essential is stronger integration of high-quality knowledge creation and technology-and policy-development, including, importantly, the creation of centers of excellence in developing regions which effectively use and produce applications-directed high quality research and bring it to bear on decision making and practices related to environmental change and sustainable management of natural resources. The authors argue that Southern centers of excellence are a necessary first step for bottom-up societal transformation towards sustainability, and that such centers must help design innovative ways to assess and place value on ecosystem services.

Este artigo discute caminhos para conciliar os objetivos do desenvolvimento das Nações Unidas para o milênio (United Nations Millennium Development Goals) com sustentabilidade ambiental em níveis regionais e globais. Os autores argumentam que o desenvolvimento e melhor uso do conhecimento, com relevantes aspectos que facilitam a sustentabilidade, é crucial e que isto demanda investimentos na capacitação científica/tecnológica, fundamentalmente nas regiões menos desenvolvidas do mundo. É essencial também uma forte integração da tecnologia com a criação do conhecimento de alto nível e a estruturação de uma política pró-desenvolvimento que incluiria a criação de centros de excelência nas regiões em desenvolvimento do mundo, as quais efetivamente produziriam pesquisas de alta qualidade com foco e aplicabilidade direta para questões regionais, com potencial efetivo de influenciar diretamente nas decisões políticas e práticas com relação às mudanças ambientais e ao manejo sustentável dos recursos naturais. Os autores argumentam também que estes centros de excelência são um primeiro passo necessário para uma transformação a partir da sociedade em direção à sustentabilidade ambiental, e que estes centros devem contribuir ao desenho de caminhos inovadores na compreensão, utilização e valorização de serviços ambientais prestados pelos ecossistemas.

A new world natural vegetation map for global change studies

We developed a new world natural vegetation map at 1 degree horizontal resolution for use in global climate models. We used the Dorman and Sellers vegetation classification with inclusion of a new biome: tropical seasonal forest, which refers to both deciduous and semi-deciduous tropical forests. SSiB biogeophysical parameters values for this new biome type are presented. Under this new vegetation classification we obtained a consensus map between two global natural vegetation maps widely used in climate studies. We found that these two maps assign different biomes in ca. 1/3 of the continental grid points. To obtain a new global natural vegetation map, non-consensus areas were filled according to regional consensus based on more than 100 regional maps available on the internet. To minimize the risk of using poor quality information, the regional maps were obtained from reliable internet sources, and the filling procedure was based on the consensus among several regional maps obtained from independent sources. The new map was designed to reproduce accurately both the large-scale distribution of the main vegetation types (as it builds on two reliable global natural vegetation maps) and the regional details (as it is based on the consensus of regional maps).

Elaborou-se um novo mapa global de vegetação natural naresolução horizontal de 1 grau para uso em modelos climáticos de circulação geral. Utilizou-se a classificação de vegetação de Dorman e Sellers com a inclusão de um novo bioma: floresta tropical estacional, que compreende as florestas tropicais decíduas e semidecíduas. Para este novo tipo de bioma, apresentaram-se os valores de parâmetros biogeofísicos domodelo de processos à superfície SSiB. Sob essa nova classificação de vegetação, obteve-se um mapa de consenso entre dois mapas globais de vegetação natural amplamente utilizados em estudos climáticos. Mostrou-se que esses dois mapas alocam biomas diferentes em cerca de 1/3 dos pontos de grade continentais. Para obter um novo mapa global de vegetação natural, as áreas de não-consenso foram preenchidas utilizando-se um conjunto de mais de 100 mapas regionais disponíveis na Internet. Para minimizar os riscos de se usar informação de baixa qualidade, os mapas regionais foram obtidos de sítios confiáveis da Internet, e o procedimento de preenchimento baseou-se no consenso entre vários mapas regionais obtidos de fontes independentes. Elaborou-se o novo mapa de modo a reproduzir em grande escala a distribuição dos principais tipos de vegetação (uma vez que se pauta em dois mapas globais de vegetação natural confiáveis) e também detalhes regionais (uma vez que se baseia em consenso de mapas regionais) com precisão.

A new world natural vegetation map for global change studies.

We developed a new world natural vegetation map at 1 degree horizontal resolution for use in global climate models. We used the Dorman and Sellers vegetation classification with inclusion of a new biome: tropical seasonal forest, which refers to both deciduous and semi-deciduous tropical forests. SSiB biogeophysical parameters values for this new biome type are presented. Under this new vegetation classification we obtained a consensus map between two global natural vegetation maps widely used in climate studies. We found that these two maps assign different biomes in ca. 1/3 of the continental grid points. To obtain a new global natural vegetation map, non-consensus areas were filled according to regional consensus based on more than 100 regional maps available on the internet. To minimize the risk of using poor quality information, the regional maps were obtained from reliable internet sources, and the filling procedure was based on the consensus among several regional maps obtained from independent sources. The new map was designed to reproduce accurately both the large-scale distribution of the main vegetation types (as it builds on two reliable global natural vegetation maps) and the regional details (as it is based on the consensus of regional maps).

Increasing risk of Amazonian drought due to decreasing aerosol pollution.

The Amazon rainforest plays a crucial role in the climate system, helping to drive atmospheric circulations in the tropics by absorbing energy and recycling about half of the rainfall that falls on it. This region (Amazonia) is also estimated to contain about one-tenth of the total carbon stored in land ecosystems, and to account for one-tenth of global, net primary productivity. The resilience of the forest to the combined pressures of deforestation and global warming is therefore of great concern, especially as some general circulation models (GCMs) predict a severe drying of Amazonia in the twenty-first century. Here we analyse these climate projections with reference to the 2005 drought in western Amazonia, which was associated with unusually warm North Atlantic sea surface temperatures (SSTs). We show that reduction of dry-season (July-October) rainfall in western Amazonia correlates well with an index of the north-south SST gradient across the equatorial Atlantic (the 'Atlantic N-S gradient'). Our climate model is unusual among current GCMs in that it is able to reproduce this relationship and also the observed twentieth-century multidecadal variability in the Atlantic N-S gradient, provided that the effects of aerosols are included in the model. Simulations for the twenty-first century using the same model show a strong tendency for the SST conditions associated with the 2005 drought to become much more common, owing to continuing reductions in reflective aerosol pollution in the Northern Hemisphere.

Climate change, deforestation, and the fate of the Amazon.

The forest biome of Amazonia is one of Earth's greatest biological treasures and a major component of the Earth system. This century, it faces the dual threats of deforestation and stress from climate change. Here, we summarize some of the latest findings and thinking on these threats, explore the consequences for the forest ecosystem and its human residents, and outline options for the future of Amazonia. We also discuss the implications of new proposals to finance preservation of Amazonian forests.

O balanço de carbono da Amazônia brasileira / The carbon balance of the brazilian amazon

Globalmente, a biota terrestre é um sumidouro significativo de dióxido de carbono (CO2) atmosférico. Estudos recentes do IPCC para a década de 1990 estimam a biota terrestre como sendo um sumidouro líquido de aproximadamente 1,4 gigatonelada de carbono por ano (assimilação líquida pela biota terrestre menos as emissões devidas às mudanças dos usos da terra). É provável que a maior parte desse suposto sumidouro aconteça nas florestas das latitudes médias e dos trópicos. Estudos do ciclo do carbono do Experimento LBA estão mostrando que as florestas não-perturbadas da Amazônia comportam-se com um forte sumidouro de carbono, com taxas na faixa de 1 a 7 toneladas por hectare por ano, ao passo que as áreas inundadas e os rios podem estar agindo como fonte de carbono de até 1,2 tonelada por hectare por ano. O desmatamento e a queima de biomassa representam uma emissão líquida de aproximadamente 0,2 gigatonelada de carbono por ano na Amazônia brasileira. Ainda que se leve em conta as grandes incertezas existentes sobre essas medidas, o balanço das evidências observacionais aponta para a possibilidade de que as florestas tropicais da América do Sul estejam funcionando como sumidouros de carbono da atmosfera.