sábado, janeiro 28, 2006

Mitos climáticos errou


Num post intitulado “aquecimento global ridículo” o blogue mitos climáticos critica um estudo publicado recentemente na revista “Nature”:

Trata-se de um artigo cómico-científico sobre a influência do designado aquecimento global na extinção das rãs! O ridículo é tanto que há quem considere extinta, sim, a credibilidade científica da Nature quanto ao tema do aquecimento global”.

A base para tal critica baseia-se no facto de a revista ter, alegadamente, publicado um artigo rejeitado por um dos avaliadores independentes do estudo:

Um peer-reviewer, a quem os editores da revista tinham solicitado um parecer sobre a proposta de publicação do artigo, tinha aconselhado a não incluí-lo na “Nature”.

Ultrajado pela decisão da revista o avaliador teria publicado o resultado da sua avaliação num blogue climático. Na dita avaliação independente, lê-se:

I presume that you will not publish this paper for the many reasons given above. If it does appear in Nature in anything close to its present form, the credibility of your journal may be beyond repair”.

Confesso que ao ler este “post” fiquei preocupado. É que a prática de rejeição de artigos na revista “Nature” (assim como na “Science”) é extremamente dura. Em geral basta que um dos três revisores independentes, a quem a revista solicita parecer, seja francamente negativo para que o artigo seja rejeitado. Portanto, a ser verdade o que diz o “post” dos “mitos climáticos”, esta seria uma excepção legitimando as interpretações feitas no blogue.

Acontece que o que está escrito nos “mitos climáticos” não corresponde à verdade. O artigo em que se baseia o “post” inclui, de facto, uma crítica feroz ao artigo da revista “Nature”. Mas o alegado relatório de avaliação do artigo nunca foi solicitado pela revista “Nature” nem sequer a ela enviado. Se o articulista dos mitos climáticos tivesse lido com atenção o que o autor da crítica escreveu teria reparado nesta frase que antecede a dita avaliação:

As a concrete example, assume that Nature’s editors had sent me this manuscript for peer-review. Here’s what I would have responded”.

Repararam no uso do condicional "would"? Quer isto dizer que a alegada revisão independente não passa de uma encenação e que o processo de avaliação da revista “Nature” decorreu com normalidade. Logo a alegada falta de credibilidade da revista “Nature” não foi manchada como proclama o articulista dos Mitos Climáticos nesta frase, no minimo, apressada:

Pois apesar do aviso dado pelo revisor científico, o artigo foi mesmo publicado e a credibilidade da revista ficou manchada”.

A ciência climática está em processo de ebulição. Todas as semanas apresentam-se novos avanços e descobertas que contribuem para consolidar conhecimento e ajudar a compreender o funcionamento global do clima e sua relevância para os sistemas que dele dependem. Concordo que existem incertezas importantes associadas à teoria do efeito de estufa. Estou convicto de que é essencial existirem cépticos motivados para re-interpretar as observações climáticas à luz de paradigmas alternativos. Assim funciona a ciência. Assim avança o conhecimento. Mas não vale a pena transformar a batalha das interpretações num jogo de manipulação fácil de informação.

5 comentários:

  1. Registo com agrado que Rui Moura acaba de publicar um "post" que corrige as afirmacoes menos correctas que foram proferidas num "post" anterior dos mitos climaticos.

    As questoes de substancia continuam em aberto para discussao mas nao vale a pena polui-las com imprecisoes.

    ResponderEliminar
  2. Anónimo29/1/06

    Estive a ler o que foi escrito no Mitos Climáticos, no Ambio e no Worl Climate Report.

    Bom, na verdade o Rui Moura, do blog Mitos Climáticos, cometeu um erro, diria talvez um lapso, que foi o de ter entendido que o autor do longo comentário no Worl Climate Report tinha sido um dos revisores científicos convidados pela Nature para apreciar o artigo de Alan Pounds sobre as rãs e o aquecimento global.

    De facto não foi. Apenas diz que, se tivesse sido convidado, teria emitido aquele comentário, desaconselhando a Nature a publicar o artigo de Alan Pounds. Portanto, no essencial, considero que o lapso do Mitos Climáticos não constitui um problema incontornável.

    Mas o putativo revisor científico, que não chegou a ser, diz algo de mais substancial. Diz que na Nature o processo de revisão pelos pares, no que respeita a artigos sobre o aquecimento global, "está morto", "foi-se", "kaput" ...

    Trata-se de uma apreciação duríssima que tem de ser levada em linha de conta. Porque, como se deprende, o que o autor quer dizer é que a Nature está a privilegiar os artigos que vêm no sentido de reforçar os efeitos perniciosos do aquecimento global. E se assim é, isso constitui um enviezamento perigosíssimo numa revista que publica artigos que se presumem científicos. Ora, por definição, a Ciência tem de ser imune a preconceitos. E a critérios enviezados.

    Jorge Oliveira

    jorge.oliveira@netcabo.pt

    ResponderEliminar
  3. O problema e' que existe um mundo de diferenca entre dizer que a revisao de um "referee" nao foi tomada em linha de conta por interesses politicos e discordar dos criterios editoriais de uma revista (que nao e' uma revista cientifica e' um "magazine").

    O autor do post do "World Climate Report" ilustra a alegada falta de credibilidade da revista Nature pelo facto de ter enviado um artigo seu a esta revista que foi rejeitado tendo depois este sido publicado numa revista da especialidade com "louvor e distincao".

    Bom mas isto nao prova nada nem sequer e' bom argumento. Eu proprio tive varias rejeicoes na revista Nature e Science e senti-me injusticado por elas. Mas como nao e' o autor que decide se o seu artigo e' publicado , paciencia. Um desses artigos, publicado noutra revista, foi depois escolhido pelos editores da Science na sua escolha mensal de artigos que constam da lista de "editors choice". Relativamente a outro foi-me dito, por um dos conselheiros editoriais da Science, que os editores operacionais erraram na decisao de rejeicao. E em relacao a outro poderia dizer o mesmo que foi dito pelo autor injusticado do World Climate Report. Os resultados nao eram positivos pelo que nao foram considerados interessantes.

    Tudo isto e' passivel de discussao. Isto e', pode-se discutir os criterios editoriais das revistas. Mas o passo entre fazer essa discussao e dizer que a revista esta' vendida a interesses politicos so' porque nao publica o nosso trabalho e' um passo de gigante.

    Note que nao estou a defender a revista Nature. Eu proprio ja' critiquei esta revista por ocasiao da publicacao de um artigo de elevado impacte sobre extincao de biodiversidade que, quanto a mim, nao tinha qualidade cientifica para ter sido publicada numa revista de tao grande impacte (Thomas et al. 2004).

    O problema e' que a revista, que e' um "magazine", nao e' indiferente a criterios de indole comercial e os editores fazem escolhas tendo presente o impacte mediatico dos artigos que escolhem. Se o artigo passa positivamente no processo de referee (que como disse no post e' duro) e se os editores julgam que o artigo pode ter impacte nos tabloides entao o artigo tem possibilidades de ser publicado.

    Se, por outro lado, o artigo e' de excelente qualidade mas os editores julgam que o impacte mediatico e' reduzido existe uma franca possibilidade que este seja recusado para ser depois publicado numa revista da especialidade.

    Estou de acordo com este criterio? Nao, nem eu nem muita gente. Ao ponto de se ter criado uma revista "Journal of Negative Results" para publicar todos os artigos que nao teem resultados atractivos para as revistas mais preocupadas com os "tabloids".

    Mas de ai a afirmar, categoricamente, que a revista Nature so' publica artigos que suportem uma determinada visao politica do mundo vai um passo que requer um pouco mais de evidencia do que aquela que foi apresentada nos blogs citados.

    ResponderEliminar
  4. Um post da lista ambio:

    bjserrano:
    "Quando se tem a obsessão de zurzir o "inimigo" ao menor pretexto e
    se procura a vitória e não a verdade, dão-se tiros nos pés ou vê-se os ditos saírem pela culatra como Rui Moura admite. Mas a possível mancha na Nature não deriva de ter ou não tido conhecimento da crítica ou mesmo de rejeitar opiniões abalizadas.
    Deriva daquilo que publica. Tinha lido o Abstract do artigo e,
    salvaguardando a minha igorância, pareceu-me um tanto pobre para
    tirar conclusões de tal forma globais. Rui Moura e o revisor não
    terão alguma razão? O assunto já veio à Ambio: não estão os
    "baluartes" da imprensa científica a aceitar cada vez mais o
    "politicamente conveniente" e a baixar de nível e de credibilidade?"

    E' certo que os criterios editoriais da Nature nao sao, infelizmente, imunes a
    apreciacoes de indole comercial. Isto e', a revista quer publicar artigos que vendam noticia. Portanto parece-me saudavel a critica e a discussao publica dos criterios editoriais da revista. Porque publica constantemente
    noticias que corroboram uma tese e - ao que parece - nao publica artigos que oferecem leituras alternativas?

    Ora tendo em conta que 1) o debate climatico esta' altamente politizado e 2) a maior parte do financiamento para investigacao climatica faz-se em torno de equipas que investigam a hipotese do efeito de estufa, e' estatisticamente esperavel que os referees da Nature estejam
    maioritariamente afectos a' corrente dominante. Ou seja, nao e' necessario que os editores sejam ostis a uma dada visao do mundo para que um artigo
    oferecendo uma interpretacao alternativa nao seja publicado. Basta que os referees o sejam.

    Isto pode parecer injusto mas e' normal em ciencia. A destruicao de um paradigma dominante faz-se com o acumular de evidencia incontornavel de sentido contrario. Na pratica isto quer dizer que para chegar a revistas
    como a Nature ou Science o nivel de evidencia de um artigo de sentido oposto a' corrente dominante tem de ser muito mais solido do que a maior parte dos artigos que professam uma visao consensual dos factos.

    Por este motivo a maior parte das ideias revolucionarias na ciencia nao sao publicadas na nature mas em artigos de revistas especializadas ou livros. So' depois de ganharem uma certa maturidade e' que passam ao clube
    do "mainstream" que e' representado por estas duas revistas.

    E' discutivel mas nao e' o fim do mundo pois existem outras revistas,
    tecnicamente muito mais crediveis, onde se podem publicar os resultados. Nao tem o mesmo impacte mediatico mas com o acumular dos anos e das
    evidencias uma ideia marginal pode tornar-se dominante.

    Finalmente e para responder a' frase final de bjserrano, e' verdade que a ultima frase do "abstract" do artigo" e' forcada e desnecessaria. Alan
    Pounds e colegas estudaram o efeito de modificacoes climaticas observadas sobre patoogenees que afectam umas determinadas ras. Nao estudaram os ciclos climaticos, nem
    fizeram modelos causais expliquem estes ciclos pelo que sentencas
    pseudo-politicas sobre a origem das alteracoes climaticas e as medidas politicas necessarias para os resolver estavam claramente fora do ambito do trabalho.

    Penso que este genero de sentencas e' mais comum entre investigadores
    norte-americanos (ainda que os Europeus nao lhes sejam imunes) em virtude da polarizacao do debate que existe em materia de alteracoes climaticas nos EUA. No dia em que Hilary Clinton chegar ao poder e os EUA assinarem
    Quioto antevejo uma reducao de tom militante nos artigos cientificos.
    Pelo menos assim espero.

    ResponderEliminar
  5. Penso que este artigo pode interessar a muitos que se interessaram por ler este post:

    Global Environmental Change Part A
    Volume 16, Issue 1 , February 2006, Pages 1-3

    Are we missing the point? Global environmental change as an issue of human
    security

    Karen O’Brien
    Department of Sociology and Human Geography, University of Oslo, Norway

    Available online 27 December 2005.

    The time has come to reframe global environmental change first and
    foremost as an issue of human security. For years, the global
    environmental change research, policy, and activist communities have been
    pointing to a long list of potential negative outcomes from human-induced
    environmental changes. The premise for concern has been that we are
    altering key components of the Earth System, changing climate and
    hydrological systems, carrying out dramatic land cover changes,
    undermining ecosystem services, and reducing genetic, ecosystem, and
    species diversity (MEA, 2005; Steffen et al., 2004). A substantial effort
    has been made to document, understand, and explain the science behind
    these issues, in order to support policies and actions that address the
    driving forces of environmental change. This science-based approach has
    produced powerful arguments for reconsidering current strategies of
    economic growth and development, in favor of what can be considered
    sustainable development. Nevertheless, the approach has maintained
    environmental change as an issue of “science” rather than of human
    security, and it has consequently failed to engage society in creating the
    transformations that will lead to sustainability.

    Human security goes beyond the traditional understanding of security as a
    state-centered concept related to threats and conflict. In terms of
    environmental change, human security can be considered the condition when
    and where individuals and communities have the options necessary to end,
    mitigate, or adapt to risks to their human, environmental, and social
    rights; have the capacity and freedom to exercise these options; and
    actively participate in attaining these options (GECHS, 1999). This is a
    people-centered concept that focuses on enabling individuals and
    communities to respond to change, whether by reducing vulnerability or by
    challenging the drivers of environmental change. More than a measurable
    and objective state, human security is something that is felt and
    experienced, and it is fundamental to every individual's well-being.

    The emphasis on “science” over “security” is evident in popular debates
    about climate change. For example, the media in Norway (as in many other
    countries) seems to be obsessed with the question, “Is this climate change
    or not?” Every extreme hurricane, storm, or heat wave raises the spectre
    of human-induced climate change. Following each major event, the Norwegian
    media gathers groups of scientists to defend their research and the strong
    scientific consensus that increased greenhouse gas emissions are changing
    the climate. Sceptical positions and scientific uncertainties are then
    equally highlighted, and anyone who has not taken graduate level
    meteorology classes is thrown into deep confusion.

    Watching the media debate the relationship between Hurricane Katrina and
    climate change in September 2005, I could not help but think that this is
    simply missing the point. The debate should not be about whether or not
    this is evidence of climate change, but about whether human society has
    the capacity to respond to these types of shocks. Focusing on scientific
    uncertainty diverts attention away from the factors that generate
    vulnerability and create human insecurities. Indeed, uncertainty about
    human impacts on the climate system is inevitable, and the more scientific
    knowledge we gain, the more uncertain we are likely to be: “Richness of
    representation and computational power only make us more aware of the
    range and variety of established uncertainties, and challenge us to
    integrate new ones” (Longley et al., 2005, p. 152). Meanwhile, evidence
    accumulates that dramatic changes are underway around the globe, including
    in the Arctic region (Stroeve et al., 2005). These changes have profound
    implications for human security, as many of the readers of this journal
    are undoubtedly aware.

    If we are confident about our ability to respond to long-term trends and
    discrete events such as Hurricane Katrina, intense rainfall in Mumbai,
    heat waves in Paris, or drought in Africa, then perhaps we can cope with
    the anticipated consequences of climate change. Unfortunately, there is
    little positive evidence of our ability to cope with these events. In
    fact, land use changes, biodiversity loss, and other environmental changes
    are undermining our ability to cope with change. It seems clear that we
    are not only failing to address current human insecurities, but we are
    adding to them in ways that few people can fully comprehend.

    What does it mean to reframe environmental change as an issue of human
    security? The framing of an issue influences the questions that are asked,
    the research that is prioritized, and the solutions and policies that are
    proposed (Forsyth, 2003). To reframe environmental change as an issue of
    human security involves asking some very relevant questions about equity,
    justice, vulnerability, power relations, and in particular, questions
    about whose security is actually threatened by environmental change. This
    demands research that analyzes environmental change within the wider
    context of the co-occurring economic, social, institutional, political,
    cultural, and technological changes taking place in the world today. It
    requires that we consider environmental issues, including climate change,
    not as isolated problems that can be cast off as a low priorities in
    relation to pressing concerns about poverty, health, and war (see Lomborg,
    2005), but as integrally connected to these concerns. The objective of
    this reframing must be to transform global environmental change into a
    fundamentally relevant human security issue that is at the core of
    decisions taken by societies that are confronted by multiple processes of
    change. This relevance will not exclude scientific research on the
    processes, impacts, and policies of global environmental change, but
    instead create a greater urgency for understanding the complexities.

    The recent catastrophe in New Orleans serves as an excellent illustration
    of the problems associated with framing global environmental change as an
    issue of science, rather than as an issue of human security (O’Brien et
    al., 2005). The disaster that occurred in late August 2005, when Hurricane
    Katrina hit the southern coast of the United States and damaged the levees
    that protect New Orleans from inundation, was not simply a natural
    disaster. Instead, it was created by years of environmental changes to the
    Mississippi Delta region linked to coastal development and flood
    management schemes. These changes were caused by river dredging and the
    construction of levees, navigation channels, and pipeline canals for oil
    development. A Scientific American article published in 2001 emphasized
    that “human activities along the Mississippi River have dramatically
    increased the risk, and now only massive reengineering of southeastern
    Louisiana can save the city” (Fischetti, 2001, p. 77). It referred the
    Mississippi Delta as the “poster child” for problems threatening the
    world's deltas, coastal wetlands, and cities on the sea.

    The media did not emphasize the role that land use changes played in the
    disaster, but instead tried to link the Category 4 hurricane to
    anthropogenic climate change. The disaster that unfolded in New Orleans
    may or may not have been linked to climate change. In any case, scientists
    studying extreme weather and climate change are increasingly able to
    “fingerprint” these events and determine attribution, at least
    probabilistically, and we may soon learn that, like the intense Paris heat
    wave of 2003 that killed thousands, Katrina reflects the impacts of human
    activities (Schär et al., 2004; Stott et al., 2004). The real issue in New
    Orleans was the disregard for human security despite a scientific
    consensus that the region constituted a “disaster waiting to happen”.

    Scientists were absolutely correct in their predictions of the
    environmental disaster that would result from a hurricane hitting New
    Orleans. What they underestimated, however, was the scale of the human
    disaster that would follow. The human disaster in Louisiana was triggered
    by vulnerabilities and inequities that have increased over the past
    decade, as social safety nets have been dismantled and institutions have
    been weakened. Neoliberal policies that emphasize personal responsibility
    and self-reliance provided little support to the most vulnerable people or
    groups. A country with a high GDP, high technological capacity, advanced
    early warning systems, and a Federal Emergency Management Agency (FEMA)
    created to manage natural disasters was expected to take appropriate
    anticipatory and response measures to secure the lives of citizens,
    residents, and visitors. The lack of an organized evacuation, and the
    chaotic rescue and relief efforts in the aftermath of the storm, suggest
    that the implications of an environmental disaster for human security had
    hardly been considered, let alone prioritized.

    As is the case with most climate hazards, Hurricane Katrina did not affect
    everybody equally. Issues of race, age, gender, and economic class
    influenced who was able to respond, both in anticipation or reaction, to
    the storm (Cutter, 2005). Among the estimated 1000 who died during or
    after the hurricane, a majority were poor, black residents who lacked the
    transportation and resources to evacuate. Elderly residents also had
    difficulty responding to the hurricane, and many of them died in hospitals
    or homes that were supposed to be responsible for their security; this
    also occurred in the 2003 heatwave in France. Finally, as Seager (2005)
    points out, there are clear gender dimensions to vulnerability in New
    Orleans, not the least because of the close association between gender and
    poverty.

    What do we need to do in order to move the debate beyond scientific
    uncertainties and towards critical reflections about how we are affecting
    human security? First, we have to recognize that we already have a good
    scientific understanding of how human-induced environmental changes
    influence the biophysical environment. For example, it is known that the
    loss of the low-lying Mississippi Delta marsh—disappearing at a rate of
    25–30 square miles a year, clears the path for storm surges to wash over
    the delta and pour into the depression that is home to New Orleans
    (Fischetti, 2001). It is also known that warmer sea-surface temperatures
    provide energy that strengthens the intensity of hurricanes (Emanuel,
    2005). The Earth is a complex system, and there are certainly many areas
    that need further study. But we do understand many of the key processes
    and their implications for human society, and using scientific uncertainty
    as a reason for inaction is simply no longer a credible excuse.

    Second, we need to realize that the context in which these changes occur
    really does matter. The context includes social, economic, technological,
    political and institutional conditions, as well as biophysical factors.
    Understanding the dynamic changes taking place in the world today, whether
    as the result of globalization, the spread of infectious diseases,
    militarism and warfare, urbanization, or other processes, is critical to
    understanding the implications of environmental change for human security
    (Leichenko and O’Brien, 2006). These changes interact with changes to the
    biophysical environment and create negative outcomes for some, and
    opportunities for others (O’Brien and Leichenko, 2003). Ironically, in
    many cases, we are eroding capacities to respond to change, at the same
    time as we are accelerating the speed and magnitude of change. The
    situation should be reversed, such that we should be enhancing the
    capacity to respond while controlling the speed and magnitude of change,
    particularly when it comes to something as comprehensive and complex as
    global systems.

    Finally, it is time to admit that current approaches to addressing
    environmental change are grossly insufficient because they are incomplete.
    Many of these approaches seek to “solve” environmental problems by
    treating them as isolated issues, external to the contexts within which we
    live. Climate change, for example, is being addressed as a pollution
    problem, divorced from its relationship to contemporary economic
    structures, development paths, and powerful interests. Consequently, we
    get the Copenhagen Consensus arguing that the costs of dealing with
    climate change will exceed the benefits, and that we are better off
    focusing on preventing the spread of HIV/AIDS, policies to attack hunger
    and malnutrition, and various proposals for trade reform (Lomborg, 2005).
    These issues may indeed be very important, but again the main point is
    missed: climate change, the loss of wetlands, forests and biodiversity,
    water pollution, and other “environmental issues” interact with social,
    economic, technological, political, and institutional dynamics and create
    new challenges for human security.

    Environmental change cannot be considered an isolated problem that can be
    addressed through better science alone. The loss of wetlands and marshes
    must be framed as an issue of human security—the 2004 Tsunami should have
    made this clear. Human security is, in fact, integrally related to the
    conditions that we create in society—conditions that are shaped by
    multiple processes of change, and that satisfy different objectives and
    represent diverse and often powerful interests. This was clear in New
    Orleans after Katrina, just as it was clear in Central America after
    Hurricane Mitch in 1998. Instead of questioning the science surrounding
    environmental change, we should perhaps begin to evaluate the visible and
    potential outcomes. This will inevitably lead us to addressing
    vulnerabilities, and to challenging the processes that are undermining
    human security.

    Framing environmental change as an issue of human security raises
    sensitive questions about justice, equity, and power. It raises questions
    of who benefits, who loses, who has power and why, and how inequities can
    be justly resolved. Perhaps this is the very reason that we are stuck
    watching endless debates focused on the state of the science, including
    “Is this climate change or not?” The truth is that our science is
    sound—our security is not. By changing the way we frame issues of
    environmental change, we can begin to see different motivations and means
    for addressing them. As the saying goes, “change the way you look at
    things, and the things you look at will change.”


    Karen O’Brien is Chair of the Global Environmental Change and Human
    Security (GECHS) project, a core project of the International Human
    Dimensions Programme (IHDP). She would like to thank Jon Barnett, Siri
    Eriksen, Robin Leichenko, Maureen Woodrow and Mike Hulme for comments on
    this editorial.


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