Geo-engenharia: nós todos queremos mudar o mundo

quarta-feira, março 31, 2010


We all want to change the world

Dealing with climate change might mean tinkering with the oceans and the atmosphere. Those who could do so would like the regulations to be clear

Mar 31st 2010 | ASILOMAR | From The Economist print edition

IN 1975 scientists expert in a new and potentially world-changing technology, genetic engineering, gathered at Asilomar, on the Monterey peninsula in California, to ponder the ethics and safety of the course they were embarking on. The year before, they had imposed on themselves a voluntary moratorium on experiments which involved the transfer of genes from one species to another, amid concerns about the risk to human health and to the environment which such “transgenic” creations might pose. That decision gave the wider world confidence that the emerging field of biotechnology was taking its responsibilities seriously, which meant that the Asilomar conference was able to help shape a safety regime that allowed the moratorium to be lifted. That, in turn, paved the way for the subsequent boom in molecular biology and biotechnology.

Another bunch of researchers, accompanied by policy experts, social scientists and journalists, gathered in Asilomar between March 22nd and 26th, hoped for a similar outcome to their deliberations. This time the topic under discussion was not genetic engineering but geoengineering—deliberately rather than accidentally changing the world’s environment.

Geoengineering is an umbrella term for large-scale actions intended to combat the climate-changing effects of greenhouse-gas emissions without actually curbing those emissions. Like genetic engineering was in the 1970s, the very idea of geoengineering is controversial. Most of those who fear climate change would prefer to stop it by reducing greenhouse-gas emissions. Geoengineers argue that this may prove insufficient and that ways of tinkering directly with the atmosphere and the oceans need to be studied. Some would like to carry out preliminary experiments, and wish to do so in a clear regulatory framework so that they know what is allowed and what is not.
Ruled in or ruled out?

Like the biotechnology of the 1970s, geoengineering cannot be treated just as science-as-usual. There are, however, important differences between the subjects. One is that in the 1970s it was clear that the ability to move genes between creatures was going to bring about a huge change in the practice of science itself, and biologists were eager for that to happen. Modern climate scientists, by contrast, usually see geoengineering research as niche, if not fringe, stuff. Many wish it would go away completely. Another difference is that in the 1970s there was a worry that DNA experiments could in themselves present dangers. With geoengineering the dangers are more likely to be caused by large-scale deployment than by any individual scientific experiment.

There are two broad approaches to geoengineering. One is to reduce the amount of incoming sunlight that the planet absorbs. The other is to suck carbon dioxide out of the atmosphere and put it somewhere else. The second of these approaches is not particularly in need of new regulation. Whether the carbon dioxide is captured by real trees, as some would like, or by artificial devices, environmental problems caused by the process would be local ones at the site of the sucking. Underground storage of the captured carbon would be regulated in the same way that carbon dioxide sequestered from power stations might be—again, for the most part, a local matter. Even the most potentially disturbing suggestion, which involves fertilising the oceans with iron in order to promote the growth of planktonic algae (in the hope that they would sink to the seabed, taking their carbon with them), can be covered by the London Convention on marine pollution, which regulates dumping at sea, and has already addressed itself to research in the area.

Read more here/Leia mais aqui: The Economist