Arquivo da tag: Emissões de carbono

One policy accounts for a lot of the decarbonisation in Joe Biden’s climate plans (The Economist)

As Democrats trim the legislation, they should focus on keeping it

Oct 12th 2021

TAKE A ROAD TRIP to Indianapolis, home to a certain two-and-a-half-mile race track, and you will find yourself in good company. A survey carried out before the pandemic found that about 85% of local commuters drive to work, alone. Standing on a bridge over 38th Street, which runs by the state fairground, you cannot escape the roar of six lanes of petrol-fired traffic below—and, reports a local, this is quiet compared with the noise on pre-virus days. Getting Americans to kick their addiction to fossil fuels will require many of these drivers to find another way of getting to work, and to move on from the flaming hydrocarbons celebrated at the city’s famous oval.

Joe Biden hopes to use what looks like a narrow window of Democratic control of Congress to encourage this transition. The last time lawmakers came close to writing climate legislation on anything like this scale was in 2009, when the Waxman-Markey bill, which would have established a trading system for greenhouse-gas emissions, was passed by the House. Since then, a Democratic White House has tried to nudge America to reduce emissions, by issuing new regulations, and a Republican White House has tried to undo them. That record illustrates what a delicate operation this is. Yet despite having a much weaker grip on Congress than Barack Obama had in the first year of his presidency, Mr Biden and his legislative allies have put forward a sweeping set of proposals for decarbonising America’s economy. These would promote everything from clean energy on the grid and electric vehicles on the road, to union jobs making green technologies and climate justice for left-behind communities.

Were this wish list passed in its entirety, which is unlikely, it would give a boost to Mr Biden’s pledge to reduce America’s emissions by roughly half from their 2005 level by 2030. A chart released by the office of Chuck Schumer, the Senate’s majority leader, suggests that implementing all of these provisions could reduce America’s emissions by 45% below 2005 levels by 2030, thus achieving almost all of Mr Biden’s goal of cutting them by roughly half in that period (see chart 1). Passing a law, even a less expansive one, would allow Mr Biden to travel to the UN climate summit in Glasgow in November representing a country that is making progress towards internationally agreed goals, rather than asking for the patience of poorer, less technologically sophisticated countries while America sorts itself out.

Some of the Democratic proposals are in a $1trn infrastructure bill with bipartisan support. But most are found in a $3.5trn budget bill that, on account of Senate rules, can only pass through a partisan parliamentary manoeuvre known as reconciliation. This requires the assent of all 50 Democratic senators. The likeliest outcome is a compromise between Democratic progressives and moderates that yokes together the agreed infrastructure bill with a much slimmer version of the $3.5trn proposal. Yet it is possible that neither bill will become law.

This raises two questions. First, how good on climate can a salami-sliced version of Mr Biden’s agenda, the result of a negotiation between 270 Democratic members of Congress each angling for their constituents’ interests, really be? Second, how bad would it be for America’s decarbonisation efforts were both bills to fail?

Happily even reconciliation-lite could bring meaningful progress if key bits of the current proposals survive the negotiations. Paul Bledsoe of the Progressive Policy Institute, a think-tank, is confident a deal “likely a bit under $2trn” will happen this month. The Rhodium Group, an analysis firm, reckons that just six proposals would cut America’s emissions by nearly 1bn tonnes in 2030 compared with no new policies (see chart 2), about a sixth of America’s total net emissions per year. That is roughly equivalent to the annual emissions from all cars and pickup trucks on American roads, or the emissions of Florida and Texas combined. The six include proposals related to “natural carbon removal” (which involves spending on forests and soil), fossil fuels (making it more expensive to emit methane) and transport (a generous credit for buyers of electric vehicles).

The big prize, though, is the power sector. Two proposals for decarbonising the grid account for the lion’s share of likely emissions reductions: a new Clean Electricity Performance Programme (CEPP) and more mundane reforms to the tax credits received by clean energy. The CEPP has been touted by Mr Biden’s cabinet officials and leading progressives as a linchpin of the climate effort. It is loosely based on the mandatory clean electricity standards imposed by over two dozen states which have successfully boosted adoption of low-carbon energy.

The CEPP is flawed in a couple of ways, though. Because it has to be primarily a fiscal measure in order to squeeze through the reconciliation process it does not involve mandatory regulation, unlike those successful state energy standards. Rather, it uses (biggish) subsidies and (rather punier) penalty fees to try to nudge utilities to build more clean energy. It is politically vulnerable because it is seen as unfriendly to natural gas and coal (unless they have expensive add-on kit to capture and store related emissions). That has incurred the hostility of Senator Joe Manchin, a Democrat who represents coal-rich West Virginia, without whose approval the bill will fail. Some influential utility companies with coal assets, including Ohio-based American Electric Power, do not like it either.

Despite the attention paid to it, CEPP is actually less potent as a greenhouse-gas slayer than those boring tax credits, which are less controversial because they do not overtly penalise coal or gas. Two energy veterans, one at a top renewables lobbying outfit and the other at a fossil-heavy utility, agree that the tax credits would sharply boost investment in low-carbon technologies. That is because they improve the current set-up by replacing stop-go uncertainty with a predictable long-term tax regime, and make tax breaks “refundable” rather than needing to be offset against tax liabilities, meaning even utilities that do not have such tax liabilities can enjoy them as freely as cash in the bank.

Thus the obsession over the CEPP is overshadowing the real star proposal. The tax credits have “a huge impact potentially”, reckons Rhodium, accounting for over one-quarter of the greenhouse-gas emissions reductions in the legislation, at a cost of roughly $150bn over ten years. A former administrator of the Environmental Protection Agency (EPA) puts it bluntly: “Take the wind and solar tax credits at ten years if you had to choose—and let everything else go.”

What if Democrats fail, the negotiations fall apart and Mr Biden is left empty handed? That would be embarrassing. And it would perhaps make it difficult to pursue ambitious federal climate policies through Congress for years, just as the failure of Waxman-Markey in 2009 haunted lawmakers. However it would not mean America can do nothing at all about climate change.
First of all, as Mr Biden’s officials have already made clear, they stand ready to use regulations to push ahead on decarbonisation efforts, just as the Obama administration did. Last month the EPA issued rules cracking-down on emissions of hydrofluorocarbons, an especially powerful greenhouse gas. The administration also has plans for loan guarantees for energy innovations and for speeding-up approvals for offshore wind farms. Yet this is tinkering compared with the federal law being discussed, especially as new regulations will likely encounter legal challenges.

Even if the federal government fails again, states and cities have climate policies too. Drawing on analysis funded by Bloomberg Philanthropies, Leon Clarke of the University of Maryland calculates that decentralised policies emulating the current best efforts of states like California could achieve roughly one-quarter of Mr Biden’s objective. But this is a bad deal: such efforts would fall a long way short of the federal proposal in terms of emissions reduction, and what reductions they achieve would be more expensive than if done at the federal level. Still, it is not nothing. Last month, Illinois passed the country’s boldest climate-change law. Democratic states such as New York and California have green policies, but Republican states such as Texas and Indiana have big wind industries too.

While Mr Clarke says Congress has to act if America is to achieve Mr Biden’s targets, he believes that progress will continue even if Congress falters, because there is now a deeper sense of ownership of climate policy among local and state governments. “The Trump years really changed the way that subnationals in the US view climate action,” he says. “They can’t rely on the federal government.”

Change is happening in surprising places. Take that flyover in Indianapolis. The city’s officials have made it into a bike path that will be connected to 55 miles of commuter-friendly trails traversing the city. $100m has been allocated for building a bus-rapid transit system, which is a cheap and efficient substitute for underground rail, with more such rapid bus lines on the cards. Bloated 38th Street will undergo a “lane diet” with car and lorry traffic yielding two lanes to the buses. Come back in a few years and the view from the bridge will be quieter.

We’re Finally Catching a Break in the Climate Fight (The Crucial Years/Bill McKibben)

As a new Oxford paper shows, the incredibly rapid fall in the cost of renewables offers hope–but only if movements can push banks and politicians hard enough

Bill McKibben – Sep 19, 2021

This is one of the first solar panels and batteries ever installed, in the state of Georgia in 1955. At the time it was the most expensive power on earth; now it’s the cheapest, and still falling fast.

So far in the global warming era, we’ve caught precious few breaks. Certainly not from physics: the temperature has increased at the alarming pace that scientists predicted thirty years ago, and the effects of that warming have increased even faster than expected. (“Faster Than Expected” is probably the right title for a history of climate change so far; if you’re a connoisseur of disaster, there is already a blog by that name). The Arctic is melting decades ahead of schedule, and the sea rising on an accelerated schedule, and the forest fires of the science fiction future are burning this autumn. And we haven’t caught any breaks from our politics either: it’s moved with the lumbering defensiveness one would expect from a system ruled by inertia and vested interest. And so it is easy, and completely plausible, to despair: we are on the bleeding edge of existential destruction.

            But one trend is, finally, breaking in the right direction, and perhaps decisively. The price of renewable energy is now falling nearly as fast as heat and rainfall records, and in the process perhaps offering us one possible way out. The public debate hasn’t caught up to the new reality—Bill Gates, in his recent bestseller on energy and climate, laments the “green premium” that must be paid for clean energy. But he (and virtually every other mainstream energy observer) is already wrong—and they’re all about to be spectacularly wrong, if the latest evidence turns out to be right.

            Last Wednesday, a team at Oxford University released a fascinating paper that I haven’t seen covered anywhere. Stirringly titled “Empirically grounded technology forecasts and the energy transition,” it makes the following argument: “compared to continuing with a fossil-fuel-based system, a rapid green energy transition will likely result in overall net savings of many trillions of dollars–even without accounting for climate damages or co-benefits of climate policy.” Short and muscular, the paper begins by pointing out that at the moment most energy technologies, from gas to solar, have converged on a price point of about $100 per megawatt hour. In the case of coal, gas, and oil, however, “after adjusting for inflation, prices now are very similar to what they were 140 years ago, and there is no obvious long-range trend.” Sun, wind, and batteries, however, have dropped exponentially at roughly ten percent a year for three decades. Solar power didn’t exist until the late 1950s; since that time it has dropped in price about three orders of magnitude.

            They note that all the forecasts over those years about how fast prices would drop were uniformly wrong, invariably underestimating by almost comic margins the drop in costs for renewable energy. This is a massive problem: “failing to appreciate cost improvement trajectories of renewables relative to fossil fuels not only leads to under-investment in critical emission reduction technologies, it also locks in higher cost energy infrastructure for decades to come.” That is, if economists don’t figure out that solar is going to get steadily cheaper, you’re going to waste big bucks building gas plants designed to last for decades. And indeed we have (and of course the cost of them is not the biggest problem; that would be the destruction of the planet.)

            Happily, the Oxford team demonstrates that there’s a much easier and more effective way to estimate future costs than the complicated calculations used in the past: basically, if you just figure out the historic rates of fall in the costs of renewable energy, you can project them forward into the future because the learning curve seems to keep on going. In their model, validated by thousands of runs using past data, by far the cheapest path for the future is a very fast transition to renewable energy: if you replace almost all fossil fuel use over the next twenty years, you save tens of trillions of dollars. (They also model the costs of using lots of nuclear power: it’s low in carbon but high in price).

            To repeat: the cost of fossil fuels is not falling; any technological learning curve for oil and gas is offset by the fact that we’ve already found the easy stuff, and now you must dig deeper. But the more solar and windpower you build, the more the price falls—because the price is only the cost of setting up the equipment, which we get better at all the time. The actual energy arrives every morning when the sun rises. This doesn’t mean it’s a miracle: you have to mine lithium and cobalt, you have to site windmills, and you have to try and do those things with as little damage as possible. But if it’s not a miracle, it’s something like a deus ex machina—and the point is that these machines are cheap.

            If we made policy with this fact in mind—if we pushed, as the new $3.5 trillion Senate bill does, for dramatic increases in renewable usage in short order, then we would not only be saving the planet, we’d be saving tons of money. That money would end up in our pockets—but it would be removed from the wallets of people who own oil wells and coal mines, which is precisely why the fossil fuel industry is working so hard to gum up the works, trying to slow down everything from electric cars to induction cooktops and using all their economic and political muscle to prolong the transition. Their economically outmoded system of energy generation can only be saved by political corruption, which sadly is the fossil fuel industry’s remaining specialty. So far the learning curve of their influence-peddling has been steep enough to keep carbon levels climbing.

            That’s why we need to pay attention to the only other piece of good news, the only other virtuous thing that’s happened faster than expected. And that’s been the growth of movements to take on the fossil fuel industry and push for change. If those keep growing—if enough of us divest and boycott and vote and march and go to jail—we may be able to push our politicians and our banks hard enough that they actually let us benefit from the remarkable fall in the price of renewable energy. Activists and engineers are often very different kinds of people—but their mostly unconscious alliance offers the only hope of even beginning to catch up with the runaway pace of global warming.

So if you’re a solar engineer working to drop the price of power ten percent a year, don’t you dare leave the lab—the rest of us will chip in to get you pizza and caffeine so you can keep on working. But if you’re not a solar engineer, then see you in the streets (perhaps at October’s ‘People vs Fossil Fuels’ demonstrations in DC). Because you’re the other half of this equation.

COVID-19 crisis causes 17 percent drop in global carbon emissions (Science Daily)

Date: May 19, 2020

Source: University of East Anglia

Summary: The COVID-19 global lockdown has had an ‘extreme’ effect on daily carbon emissions, but it is unlikely to last, according to a new analysis.

Coronavirus and world | Credit: © Photocreo Bednarek /

Coronavirus and world concept illustration (stock image). Credit: © Photocreo Bednarek /

The COVID-19 global lockdown has had an “extreme” effect on daily carbon emissions, but it is unlikely to last — according to a new analysis by an international team of scientists.

The study published in the journal Nature Climate Change shows that daily emissions decreased by 17% — or 17 million tonnes of carbon dioxide — globally during the peak of the confinement measures in early April compared to mean daily levels in 2019, dropping to levels last observed in 2006.

Emissions from surface transport, such as car journeys, account for almost half (43%) of the decrease in global emissions during peak confinement on April 7. Emissions from industry and from power together account for a further 43% of the decrease in daily global emissions.

Aviation is the economic sector most impacted by the lockdown, but it only accounts for 3% of global emissions, or 10% of the decrease in emissions during the pandemic.

The increase in the use of residential buildings from people working at home only marginally offset the drop in emissions from other sectors.

In individual countries, emissions decreased by 26% on average at the peak of their confinement.

The analysis also shows that social responses alone, without increases in wellbeing and/or supporting infrastructure, will not drive the deep and sustained reductions needed to reach net zero emissions.

Prof Corinne Le Quéré of the University of East Anglia, in the UK, led the analysis. She said: “Population confinement has led to drastic changes in energy use and CO2 emissions. These extreme decreases are likely to be temporary though, as they do not reflect structural changes in the economic, transport, or energy systems.

“The extent to which world leaders consider climate change when planning their economic responses post COVID-19 will influence the global CO2 emissions paths for decades to come.

“Opportunities exist to make real, durable, changes and be more resilient to future crises, by implementing economic stimulus packages that also help meet climate targets, especially for mobility, which accounts for half the decrease in emissions during confinement.

“For example in cities and suburbs, supporting walking and cycling, and the uptake of electric bikes, is far cheaper and better for wellbeing and air quality than building roads, and it preserves social distancing.”

The team analysed government policies on confinement for 69 countries responsible for 97% of global CO2 emissions. At the peak of the confinement, regions responsible for 89% of global CO2 emissions were under some level of restriction. Data on activities indicative of how much each economic sector was affected by the pandemic was then used to estimate the change in fossil CO2 emissions for each day and country from January to April 2020.

The estimated total change in emissions from the pandemic amounts to 1048 million tonnes of carbon dioxide (MtCO2) until the end of April. Of this, the changes are largest in China where the confinement started, with a decrease of 242 MtCO2, then in the US (207 MtCO2), Europe (123 MtCO2), and India (98 MtCO2). The total change in the UK for January-April 2020 is an estimated 18 MtCO2.

The impact of confinement on 2020 annual emissions is projected to be around 4% to 7% compared to 2019, depending on the duration of the lockdown and the extent of the recovery. If pre-pandemic conditions of mobility and economic activity return by mid-June, the decline would be around 4%. If some restrictions remain worldwide until the end of the year, it would be around 7%.

This annual drop is comparable to the amount of annual emission reductions needed year-on-year across decades to achieve the climate objectives of UN Paris Agreement.

Prof Rob Jackson of Stanford University and Chair of the Global Carbon Project who co-authored the analysis, added: “The drop in emissions is substantial but illustrates the challenge of reaching our Paris climate commitments. We need systemic change through green energy and electric cars, not temporary reductions from enforced behavior.”

The authors warn that the rush for economic stimulus packages must not make future emissions higher by delaying New Green Deals or weakening emissions standards.

‘Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement’, Corinne Le Quéré, Robert B. Jackson, Matthew W. Jones, Adam J. P. Smith, Sam Abernethy, Robbie M. Andrew, Anthony J. De-Gol, David R. Willis, Yuli Shan, Josep G. Canadell, Pierre Friedlingstein, Felix Creutzig, Glen P. Peters, is published in Nature Climate Change on May 19.

The research received support from the Royal Society, the European Commission projects 4C, VERIFY and CHE, the Gordon and Betty Moore Foundation, and the Australian National Environmental Science Program.

Story Source:

Materials provided by University of East Anglia. Note: Content may be edited for style and length.

Journal Reference:

  1. Corinne Le Quéré, Robert B. Jackson, Matthew W. Jones, Adam J. P. Smith, Sam Abernethy, Robbie M. Andrew, Anthony J. De-Gol, David R. Willis, Yuli Shan, Josep G. Canadell, Pierre Friedlingstein, Felix Creutzig, Glen P. Peters. Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement. Nature Climate Change, 2020; DOI: 10.1038/s41558-020-0797-x

Brasil tem de modernizar pecuária para combater mudança do clima (Folha de S.Paulo)

Marcelo Leite

30/10/2016  02h00

As emissões de carbono aumentaram 3,5% enquanto o PIB atrofiava 3,8%O As emissões de carbono aumentaram 3,5% enquanto o PIB atrofiava 3,8%. Apu Gomes/Folhapress

Brasil deu uma rasteira no clima do planeta em 2015. No ano em que se aprovou o Acordo de Paris para conter o aquecimento global, o país aumentou, em vez de diminuir, a produção de gases do efeito estufa. A maior parte da culpa cabe à agropecuária.

Não poderia ser pior a notícia divulgada na quarta-feira (26) pelo Sistema de Estimativa de Emissão de Gases do Efeito Estufa, da rede de ONGs Observatório do Clima.

As emissões de carbono aumentaram 3,5% enquanto o PIB atrofiava 3,8%. Em geral, essas coisas andam juntas: para produzir mais, gasta-se mais energia, que no mundo todo é a principal fonte de gases que, como o CO2, ajudam a aquecer a atmosfera por impedir a dissipação de radiação de origem solar.

Não no Brasil. Aqui a atividade que mais contribui para agravar o efeito estufa é a mudança do uso da terra. Grosso modo, desmatamento, com a Amazônia à frente.

A destruição de florestas responde, sozinha, por 46% de toda a poluição climática lançada pelos brasileiros em 2015. Segundo o Seeg, o desmatamento emitiu o equivalente a 875 milhões do total de 1,9 bilhão de toneladas de CO2.

Quando a floresta é derrubada para abrir espaço a campos e pastos, toda a biomassa que havia ali –troncos, folhas, raízes etc.– acaba chegando à atmosfera na forma de compostos de carbono que agravam o aquecimento global. Queimadas e apodrecimento são os principais processos.

Isso não é tudo. As plantações e o gado, além de provocar desmatamento, também originam emissões na própria atividade, como o famigerado “arroto da vaca” (metano proveniente da fermentação entérica ou digestão de celulose).

Noves fora, a agropecuária representa 69% –mais de dois terços– de todas as emissões nacionais. É muita coisa para um setor que empregava menos de 17 milhões de pessoas em 2006 (último censo do setor) e, em 2015, respondeu por 21% do PIB brasileiro.

Só agricultura e pecuária tiveram produção em alta no ano passado. Indústria e serviços recuaram, atrofiando a demanda por energia e transporte, outras fontes importantes de gases do efeito estufa. Com isso, cresceu a participação relativa das mudanças no uso da terra.

Além do mais, o desmatamento cresceu também em termos absolutos. Segundo o Instituto Nacional de Pesquisas Espaciais (Inpe), na Amazônia –onde estão as maiores florestas do Brasil– o aumento foi de 24%. Partimos de 5.012 km2 em 2014 para 6.207 km2 de floresta perdida em 2015 (área correspondente a quatro municípios de São Paulo).

A pecuária bovina sozinha, com seus 215 milhões de cabeças, foi a causa do equivalente a 240 milhões de toneladas de CO2, em 2015, só com a fermentação entérica. Isso dá 12,6% das emissões brasileiras.

Na média a pecuária de corte no Brasil utiliza uma cabeça por hectare. Dobrando ou triplicando essa baixíssima produtividade, sobretudo por meio da recuperação de pastos, dá para reduzir a emissão de carbono a quase zero.

Criar bois “verdes” é a bola da vez. O Brasil é capaz de fazer isso, com regulação, tecnologia e crédito, assim como aumentou a produtividade no cultivo de grãos e derrubou a taxa de desmatamento de 2005 para cá (ainda que ela esteja subindo de novo).

66% das emissões brasileiras de CO2 vêm de atividade agropecuária (Folha de S.Paulo)

Phillippe Watanabe


O desmatamento, de modo isolado, libera as emissões de gases

A agropecuária é a responsável pela maior parte da emissão de gases estufa no Brasil. Quando considerados desmatamento para atividade agropecuária e o exercício direto dela, a porcentagem das emissões chega a cerca de 66%.

Os dados são do Seeg (Sistema de Estimativa de Emissão de Gases Estufa), realizado pelo OC (Observatório do Clima). O relatório, lançado nesta terça (6), na sede do SOS Mata Atlântica, analisa a evolução histórica das emissões brasileiras.

Considerando dados referentes ao ano de 2014, de forma direta, 23% das emissões de CO2 no Brasil são provenientes da agropecuária. Dentro desse universo, 76% das emissões estão relacionadas à pecuária, sendo 64% derivados do consumo de carne (bovinos de corte), segundo dados da Imaflora, parte do OC.

A mudança de uso da terra é líder de emissões no país, com cerca 42%. O termo, de forma geral, se refere aos desmatamentos, normalmente associados à atividade agropecuária. Esse tipo de emissão somado aos 23% emitidos diretamente pela ação agropecuária alcançam o valor aproximado de 66%.

Segundo dados do Imazon, também parte do OC, com uma melhor aplicação da legislação ambiental atual seria possível aumentar a arrecadação em mais de R$ 1 bilhão por ano.

A energia é a segunda colocada entre as fontes dos gases estufa, com 26%. Essas emissões vêm crescendo anualmente, em parte por conta da crise na produção de energia hidrelétrica.

Segundo o Instituto de Energia e Meio Ambiente, que também faz parte do OC, quase metade (46%) das emissões relacionadas à energia estão associadas ao transporte, tanto de carga quanto de passageiros.


Os dados levantados pelo OC mostram que o Brasil, caso cumpra os compromissos firmados no Acordo de Paris, como restauração e reflorestamento de matas, recuperação de pastos, entre outros, conseguirá reduzir as emissões de gases estufa mais do que o planejado no INDC (Contribuições Nacionalmente Determinadas Pretendidas).

“O nosso estudo aponta que dá para ser mais ambicioso”, afirma Tasso de Azevedo, coordenador do Seeg.

Sequestro de CO2 (Pesquisa Fapesp)

Reunimos o que já publicamos sobre o processo de captura de dióxido de carbono da atmosfera, que se dá sobretudo em florestas e oceanos e ajuda a manter equilibrados os níveis de CO2 na atmosfera

Edição Online 13:10 27 de junho de 2016


mini Florestas secundárias podem contribuir para mitigar as mudanças climáticas
Se protegido adequadamente, esse tipo de vegetação neutralizaria as emissões da América Latina e do Caribe acumuladas entre 1993 e 2014 |Junho/2016|
MAR_Abre-Boletim Fundo do mar teve estoque de carbono
Circulação de água no Oceano Atlântico pode explicar baixos níveis de CO2 atmosférico no Último Máximo Glacial |Junho/2016|
Árvores da Amazônia geram novas folhas mesmo durante a seca
Estocagem de água no solo no período de chuvas é crucial nesse processo, segundo estudo publicado na revista Science |Fevereiro/2016|
Extinção de animais pode agravar efeito das mudanças climáticas
Ausência de espécies frugívoras de grande porte pode interferir no processo de sequestro de CO2 da atmosfera |Dezembro/2015|
Florestas em transformação
Trepadeiras estão remodelando a Amazônia, e os bambus, a mata atlântica |Outubro/2014|
068-069_Algas_222 Microalgas transformadas
Membrana que filtra meio de cultura permite selecionar biomassa com proteínas, ácidos graxos ou carboidratos |Agosto/2014|
022-027_Entrevista_217 Entrevista: Luciana Vanni Gatti
Química explica estudo sobre o balanço de carbono na Amazônia |Março/2014|
036-041_Manguezais_216 Rede de proteção
Manguezais ganham importância diante de alterações no clima |Fevereiro/2014|
brown_river_small Emissão desequilibrada
Floresta amazônica pode estar enviando mais CO2 à atmosfera durante período de seca |Fevereiro/2014|
030-033_cana_159 Balanço sustentável
Estudo da Embrapa atualiza as vantagens do etanol no combate aos gases causadores do efeito estufa |Maio/2009|
chuva As poderosas águas dos rios
Turbinadas pelo aquecimento global, variações no regime de chuvas na bacia do Prata podem tumultuar a circulação marinha no Sul e Sudeste |Janeiro/2008|
Castanheira da amazônia Abrindo o guarda-chuva verde
As cidades precisam de mais árvores, mas há prós e contras em plantar mais exemplares no meio urbano |Outubro/2007|
art3269img1 Tecnologia contra o aquecimento global
Brasil sai na frente com etanol, biodiesel e plantio direto |Junho/2007|
art3179img1 O dia depois de amanhã
Pesquisadores unem-se para esmiuçar os efeitos do aquecimento global no Brasil|Março/2007|
botanica O jatobá contra a poluição
Árvores tropicais podem ser opção para limpar atmosfera caso o efeito estufa aumente|Outubro/2002|
Castanheira da amazônia Impactos irreversíveis do desmatamento
Mata recuperada absorve menos gás carbônico do que até agora se pensava |Abril/2000|

EUA apresentam programa mais ambicioso de sua História contra as mudanças climáticas (O Globo)

Obama anuncia o Plano Energia Limpa, para reduzir emissões em usinas termelétricas e incentivar uso de fontes renováveis


03/08/2015 6:00

Alvo. Usina termelétrica em Nova York: projeto apresentado por Obama obrigará instalações a acelerarem desenvolvimento em fontes de energia renováveis, como a eólica e a solar; – LUKE SHARRETT / NYT

WASHINGTON – Na investida mais forte já tomada pelos EUA para combater as mudanças climáticas, o presidente Barack Obama apresentará hoje o Plano de Energia Limpa, uma série de medidas concebidas para reduzir drasticamente as emissões de usinas termelétricas, substituindo o uso de combustíveis fósseis por fontes renováveis, como a eólica e a solar.

O plano será uma visão final e mais ambiciosa dos regulamentos esboçados em 2012 e 2014 pela Agência de Proteção Ambiental (EPA, na sigla em inglês) do país. O novo regulamento pode culminar no fechamento de usinas de energia movidas a carvão, que ainda movimentam uma fatia significativa da economia americana.

Obama elegeu o combate às mudanças climáticas como uma prioridade em seu segundo mandato à frente da Casa Branca. Em um vídeo postado na madrugada de domingo na conta da Casa Branca no Facebook, ele avaliou que o clima afeta a “economia, a segurança e a saúde”.

“Todos os desastres estão se tornando mais frequentes, caros e perigosos. As mudanças climáticas não são um problema para outra geração. Não mais”, ressaltou, enquanto o vídeo exibia uma foto de sua família.

O presidente destacou que, até agora, o governo americano nunca impôs limites para a quantidade de carbono emitida pelas usinas termelétricas.

O plano exige que as usinas termelétricas reduzam em 32% suas emissões até 2030, em relação aos níveis medidos em 2005. No rascunho do plano, este índice era de 30%.

Outra novidade é a imposição de que as usinas acelerem a transição para energias renováveis, aumentando de 22% para 28% o uso das fontes que não emitem carbono na atmosfera.

Os climatologistas alertam que a atual emissão de gases-estufa está levando o planeta à escalada da temperatura média global para mais de 2 graus Celsius, deixando-o vulnerável à ocorrência de eventos extremos, como a elevação do nível do mar, tempestades devastadoras e estiagens.


Os novos mandamentos de Obama não serão suficientes para tirar o planeta do caos climático. Os cientistas, no entanto, avaliam que é possível evitar uma catástrofe. Para isso, regras semelhantes às propostas pelo presidente americano devem ser adotadas por governantes de outros grandes países poluidores, como a Índia e a China. E o sucessor de Obama deve ser ainda mais intolerante com os gases-estufa, aprimorando o projeto divulgado hoje.

Obama pretende usar seu novo plano para pressionar outros países a assumirem metas ambiciosas para reduzir suas emissões de carbono. De acordo com o Painel Intergovernamental de Mudanças Climáticas, todas as nações devem apresentar compromissos voluntários sobre seus cortes de emissões nos próximos meses. Os documentos, então, serão discutidos em dezembro na Conferência do Clima de Paris, um encontro de chefes de Estado de todo o mundo que discutirão um acordo global contra as mudanças do clima.

Os primeiros passos do presidente americano foram traçados ainda no ano passado, em Pequim. Obama anunciou que os EUA cortariam a emissão de gases-estufa em 28% até 2025, em relação aos níveis de 2005. Já o mandatário chinês, Xi Jinping, afirmou que o país atingiria o pico da liberação de carbono até, no máximo, 2030. Somados, os países são responsáveis por 45% das emissões de poluentes no planeta.

— (O Plano de Energia Limpa) é um sinal do esforço interno do governo e de seu esforço internacional contra as mudanças climáticas — avaliou Durwood Zaelke, presidente do Instituto para Governança e Desenvolvimento Sustentável. — É um passo diplomático relevante dos EUA nos últimos meses antes da Conferência de Paris. Isso pode servir como alavanca para as outras grandes economias: China, Índia, Brasil, África do Sul, Indonésia.

Opositores do projeto o classificam como um instrumento que aumentará o desemprego, o preço do consumo de energia e a pressão sobre a credibilidade das usinas de energia. Governadores republicanos classificam o plano como uma intromissão do governo federal em assuntos econômicos que não estão em sua esfera.

A Casa Branca rebate as acusações. Segundo o governo, o novo plano levará a uma economia familiar anual de US$ 85 no consumo de energia e trará benefícios à saúde, como a redução dos poluentes que causam asma — cuja incidência mais do que duplicou nos últimos 30 anos — e doenças pulmonares. Obama assegura que considerou os argumentos de seus adversários políticos e, por isso, aumentou em dois anos, até 2022, o prazo para o corte almejado das emissões.


Em um encontro na Alemanha em junho, os líderes do G7 concordaram que as emissões de gases de efeito estufa devem ser zeradas até o fim do século. Para isso, a liberação de poluentes deveria ser reduzida de 40% a 70% até 2050, em relação aos níveis de 2010.

Os chefes de Estado das sete nações mais ricas do mundo também garantiram que doarão US$ 100 bilhões por ano, até 2020, para ajudar as nações mais pobres do planeta a desenvolver tecnologia para mitigação e adaptação contra as mudanças climáticas — a prioridade seria os países africanos e insulares, que receberiam US$ 400 milhões para criar sistemas de alerta precoce que prevenissem sua população de eventos extremos. A iniciativa, porém, não é nova. O Fundo Verde, como atende o programa, foi criado em 2009, mas jamais saiu do papel.

O Brasil também já anunciou sua primeira ação. Em visita à Casa Branca em julho, a presidente Dilma Rousseff analisou a restauração de 12 milhões de hectares degradados até 2030.