(29214)
(13458)
(12648)
(10503)
(9080)
(5981)
(5047)
(4348)
(4172)
(3326)
(3249)
(2790)
(2388)
(2365)
impactos mudança climática fim do ambientalismo revolução energética
2008-08-22
Warming warnings get overheated
Alarmist predictions of climate change like Oliver Tickell's are not just bad science – they stop us thinking rationally about solutions

Much of the global warming debate is perhaps best described as a constant outbidding by frantic campaigners, producing a barrage of ever-more scary scenarios in an attempt to get the public to accept their civilisation-changing proposals. Unfortunately, the general public – while concerned about the environment – is distinctly unwilling to support questionable solutions with costs running into tens of trillions of pounds. Predictably, this makes the campaigners reach for even more outlandish scares.

These alarmist predictions are becoming quite bizarre, and could be dismissed as sociological oddities, if it weren't for the fact that they get such big play in the media. Oliver Tickell, for instance, writes that a global warming causing a 4C temperature increase by the end of the century would be a "catastrophe" and the beginning of the "extinction" of the human race. This is simply silly.

His evidence? That 4C would mean that all the ice on the planet would melt, bringing the long-term sea level rise to 70-80m, flooding everything we hold dear, seeing billions of people die. Clearly, Tickell has maxed out the campaigners' scare potential (because there is no more ice to melt, this is the scariest he could ever conjure). But he is wrong. Let us just remember that the UN climate panel, the IPCC, expects a temperature rise by the end of the century between 1.8 and 6.0C. Within this range, the IPCC predicts that, by the end of the century, sea levels will rise 18-59 centimetres – Tickell is simply exaggerating by a factor of up to 400.

Tickell will undoubtedly claim that he was talking about what could happen many, many millennia from now. But this is disingenuous. First, the 4C temperature rise is predicted on a century scale – this is what we talk about and can plan for. Second, although sea-level rise will continue for many centuries to come, the models unanimously show that Greenland's ice shelf will be reduced, but Antarctic ice will increase even more (because of increased precipitation in Antarctica) for the next three centuries. What will happen beyond that clearly depends much more on emissions in future centuries. Given that CO2 stays in the atmosphere about a century, what happens with the temperature, say, six centuries from now mainly depends on emissions five centuries from now (where it seems unlikely non-carbon emitting technology such as solar panels will not have become economically competitive).

Third, Tickell tells us how the 80m sea-level rise would wipe out all the world's coastal infrastructure and much of the world's farmland – "undoubtedly" causing billions to die. But to cause billions to die, it would require the surge to occur within a single human lifespan. This sort of scare tactic is insidiously wrong and misleading, mimicking a firebrand preacher who claims the earth is coming to an end and we need to repent. While it is probably true that the sun will burn up the earth in 4-5bn years' time, it does give a slightly different perspective on the need for immediate repenting.

Tickell's claim that 4C will be the beginning of our extinction is again many times beyond wrong and misleading, and, of course, made with no data to back it up. Let us just take a look at the realistic impact of such a 4C temperature rise. For the Copenhagen Consensus, one of the lead economists of the IPCC, Professor Gary Yohe, did a survey of all the problems and all the benefits accruing from a temperature rise over this century of about approximately 4C. And yes, there will, of course, also be benefits: as temperatures rise, more people will die from heat, but fewer from cold; agricultural yields will decline in the tropics, but increase in the temperate zones, etc.

The model evaluates the impacts on agriculture, forestry, energy, water, unmanaged ecosystems, coastal zones, heat and cold deaths and disease. The bottom line is that benefits from global warming right now outweigh the costs (the benefit is about 0.25% of global GDP). Global warming will continue to be a net benefit until about 2070, when the damages will begin to outweigh the benefits, reaching a total damage cost equivalent to about 3.5% of GDP by 2300. This is simply not the end of humanity. If anything, global warming is a net benefit now; and even in three centuries, it will not be a challenge to our civilisation. Further, the IPCC expects the average person on earth to be 1,700% richer by the end of this century.

Tickell's hellfire and damnation sermon also misinforms us of the solutions to global warming: panicking is rarely the right state of mind for finding smart solutions. In essence, Tickell says that because the outlook is so frightening, we need to cut much, much more than the Kyoto protocol called for. Now, all peer-reviewed, published economic models demonstrate that such an effort is a colossal waste of money – one of the leading models shows that, for every pound spent, Tickell's solution would do about 13p-worth of good.

Tickell finds that current climate efforts like Kyoto have been "miserable failures", which is true, but makes it seem rather odd that he thinks much-more-of-the-same will suddenly be great policy. He claims that the reason these policies are not realised is because our governments are "craven to special interests". While this is convenient to believe, it is, of course, incorrect; the real reason is that no one in the electorate wants to pay £2, £3 or even £4 for a litre of petrol.

If we are to find a workable and economically smart solution, we would do well to look at the best climate solution from the top economists from the Copenhagen Consensus. They found that, unlike even moderate CO2 cuts, which cost more than they do good, we should focus on investing in finding cheaper low-carbon energy. This requires us to invest massively in energy research and development (R&D). Right now, we don't – because the climate panic makes us focus exclusively on cutting CO2.

R&D has been dropping worldwide since the early 1980s. If we increased this investment ten-fold, it would still be ten times cheaper than Kyoto, and probably hundreds to thousands of times cheaper than Tickell's proposal. The literature indicates that for every pound invested, we would do £11-worth of good. The reason: because when we all talk about cutting CO2, we might get some well-meaning westerners to put up a few inefficient solar panels on their roof-tops. While it costs a lot, it will do little and have no impact on Chinese and Indian emissions. But if we focus on investing in making cheaper solar panels, they will become competitive sooner, making everyone, including the Chinese and Indians, switch.

Such a proposal is efficient, politically feasible and will actually fix climate change in the medium term. Being panicked by incorrect data and suggesting outlandish policies might create a splash, but it will stall our prospects of achieving real change.

Let's not be silly – let's choose the best solution.

(By Björn Lomborg, The Guardian, 15/08/2008)

desmatamento da amazônia (2116) emissões de gases-estufa (1872) emissões de co2 (1815) impactos mudança climática (1528) chuvas e inundações (1498) biocombustíveis (1416) direitos indígenas (1373) amazônia (1365) terras indígenas (1245) código florestal (1033) transgênicos (911) petrobras (908) desmatamento (906) cop/unfccc (891) etanol (891) hidrelétrica de belo monte (884) sustentabilidade (863) plano climático (836) mst (801) indústria do cigarro (752) extinção de espécies (740) hidrelétricas do rio madeira (727) celulose e papel (725) seca e estiagem (724) vazamento de petróleo (684) raposa serra do sol (683) gestão dos recursos hídricos (678) aracruz/vcp/fibria (678) silvicultura (675) impactos de hidrelétricas (673) gestão de resíduos (673) contaminação com agrotóxicos (627) educação e sustentabilidade (594) abastecimento de água (593) geração de energia (567) cvrd (563) tratamento de esgoto (561) passivos da mineração (555) política ambiental brasil (552) assentamentos reforma agrária (552) trabalho escravo (549) mata atlântica (537) biodiesel (527) conservação da biodiversidade (525) dengue (513) reservas brasileiras de petróleo (512) regularização fundiária (511) rio dos sinos (487) PAC (487) política ambiental dos eua (475) influenza gripe (472) incêndios florestais (471) plano diretor de porto alegre (466) conflito fundiário (452) cana-de-açúcar (451) agricultura familiar (447) transposição do são francisco (445) mercado de carbono (441) amianto (440) projeto orla do guaíba (436) sustentabilidade e capitalismo (429) eucalipto no pampa (427) emissões veiculares (422) zoneamento silvicultura (419) crueldade com animais (415) protocolo de kyoto (412) saúde pública (410) fontes alternativas (406) terremotos (406) agrotóxicos (398) demarcação de terras (394) segurança alimentar (388) exploração de petróleo (388) pesca industrial (388) danos ambientais (381) adaptação à mudança climática (379) passivos dos biocombustíveis (378) sacolas e embalagens plásticas (368) passivos de hidrelétricas (359) eucalipto (359)
- AmbienteJá desde 2001 -