Archivo de la etiqueta: Mitigación

Iron Dumping In The Pacific Ocean Stirs Controversy Over Geoengineering

[Visto: 1038 veces]

Este artículo del Hufftington Post aporata algunasideas al debate sobre el controversial tema de la geoingeniería. En este caso el objetivo es recuperar la presncia del salmón en las costas occidentales de Canadá, sin embargo el experimento tiene implicancias mayores si se lo ve como una forma de capturar CO2 de la atmósfera.

From Stephanie Pappas, LiveScience Senior Writer:

A controversial experiment in which more than 200,000 pounds of iron sulfate were dumped into the Pacific Ocean west of Canada has scientists calling for more transparency in geoengineering.

Geoengineering is any deliberate and large-scale manipulation of environmental processes in order to impact Earth’s climate. Some geoengineering projects, like the recent one, can have other impacts like boosting fish populations.

20121128-o-iron-dumping-pacific-ocean-570.jpg

The project was conducted by a local group, the Haida Salmon Restoration Corporation, under the scientific advice of American businessman Russ George, formerly the CEO of a company called Planktos, Inc. The goal, according to Haida Salmon Restoration Corporation, was to trigger plankton blooms to restore salmon and other fish populations. Phytoplankton, teensy floating plants at the base of the ocean food chain, need iron to grow.

Similar ocean-fertilization schemes have been proposed as a way to lessen climate change, as phytoplankton take up carbon dioxide on the ocean’s surface and sink to the bottom, removing carbon from the atmosphere.

This geoengineered approach to solving climate change is controversial, but even researchers who think it has promise said the Canadian experiment went about it the wrong way.

“It should have been done by a group of neutral scientists,” said Victor Smetacek, a researcher at the Alfred Wegener Institute in Germany who conducted a small-scale ocean-fertilization experiment in 2009. Smetacek added, “The thing is, it’s going to give iron fertilization a bad name.”

Chlorophyll levels off Canada’s west coast in August, 2011, before the controversial fertilization project. This Giovanni data portal provides standard and evaluation ocean color radiometric data products from SeaWiFS and MODIS. These data products are in support of the NASA Water Quality for Coastal and Inland Waters project, and the National Oceanographic and Atmospheric Administration

20121128-o-chlorophyll-570.jpg

Sigue leyendo

14 medidas para disminuir la contaminación, salvar vidas y frenar el calentamiento global – New study urges smart targeting of pollution sources to save lives..

[Visto: 2141 veces]

13 January 2012

A new international study published in Science has shown that implementing 14 key air pollution control measures could slow the pace of global warming, save millions of lives and boost agricultural production.

The study was led by Drew Shindell of NASA’s Goddard Institute for Space Studies and included scientists from the Stockholm Environment Institute (SEI) at the University of York, King’s College London and the UK Centre for Ecology & Hydrology. Researchers identified 14 measures targeting methane and black carbon emissions that could slow global mean warming by approximately 0.5ºC by 2050. The measures could also prevent between 700,000 and 4.7 million premature deaths each year and increase global crop yields by between 30 million and 135 million tonnes per season.

While all regions of the world would benefit, avoided warming is greatest in central and northern Asia, southern Africa and around the Mediterranean, total numbers of avoided premature deaths are greatest in Asia and Africa and the greatest total tonnage gains in crop production are estimated to occur in China, India and the US, followed by Pakistan and Brazil. Countries in South Asia and the Sahel region of Africa could see considerable reduction in the disruption of rainfall patterns.

Black carbon, a product of the incomplete combustion of fossil fuels or biomass such as wood or agricultural crop residues, damages human health by entering the lungs and exacerbating a number of respiratory diseases. It also absorbs radiation from the sun causing the atmosphere to warm and rainfall patterns to shift and reduces the reflectivity of bright surfaces, such as ice and deserts, a process that hastens global warming. Methane is a precursor to ground-level or lower atmosphere ozone, a component of health-sapping smog, and is also a potent greenhouse gas. Ground level ozone at current levels also damages plants and reduces agricultural yields in sensitive areas.

Dr Johan Kuylenstierna, the Director of SEI at York, said: “All 14 measures are based on existing technologies and can be implemented immediately, so do not require long development processes.”

Another co-author of the study, Professor Martin Williams from the Environmental Research Group at King’s College London, said: “Measures taken now to reduce carbon dioxide emissions will not have any effect on the global climate for another 40-50 years. We have shown that there are things we can do to begin to mitigate the temperature increases already being seen.’’

“The combination of methane and black carbon measures along with substantial carbon dioxide emissions reductions has a high probability of limiting global mean warming to <2ºC during the next 60 years, something which neither set of emissions reductions achieves on its own.”

Professor David Fowler of the Centre for Ecology & Hydrology, added: “These control measures represent many win–win options with benefits for human health and climate as well as reducing waste, for example with the methane controls.”

Black carbon and methane pollutants come from a wide variety of sources and the 14 measures identified by the study have all been successfully applied in different parts of the world.

“These control measures represent many win–win options with benefits for human health and climate as well as reducing waste, for example with the methane controls.”
Professor David Fowler, Centre for Ecology & Hydrology

For methane, the key strategies the scientists considered in their analysis were capturing gas that would otherwise escape from coal mines and oil rigs, reducing leakage from long-distance gas pipelines, preventing methane emissions in city landfills, updating city wastewater treatment plants, aerating rice paddies more frequently, and limiting emissions on farms from manure.

For black carbon, the strategies analyzed include installing particle filters in diesel vehicles, keeping high-emitting vehicles off the road, upgrading cook stoves and boilers to cleaner burning types, installing more efficient kilns for brick production, upgrading coke ovens and banning agricultural burning.

The research team used sophisticated emission, air quality and climate models (e.g. IIASA GAINS, NASA GISS and ECHAM) to estimate the impact of emissions reductions. The modelling shows that the benefits from the methane reductions would be widespread because methane is evenly distributed throughout the atmosphere. The methane measures if fully implemented will to large global climate and agriculture benefits and relatively small human health benefits, all with high confidence and worldwide distribution.

The black carbon measures are likely to provide substantial global climate benefits, but uncertainties are much larger. There is more certainty for the black carbon measures concerning the large regional human health benefits as well as reductions in regional rainfall disruptions, ice melting in both the Arctic and the Himalayas and improvements in regional agricultural yields.

Additional information

The Stockholm Environment Institute (SEI) at the University of York issued a press release for this story.

Read the paper, “Simultaneously Mitigating Near-Term Climate and Improving Human Health and Food Security” in Science.

Staff page and research interests of Professor David Fowler

Sigue leyendo

La eficiencia energética es el camino más rápido contra el calentamiento, según EE UU

[Visto: 1285 veces]

El secretario de Energía de Obama insta a todos los países a invertir en edificios ecológicos

Steven Chu, ministro de Energía estadounidense y premio Nobel de física, ha instado a todos los países a invertir en el diseño de edificios ecológicos para lograr una drástica reducción del consumo de energía tanto de los hogares como de las empresas.

En un artículo que publica hoy en el diario The Times, Chu defiende la “eficiencia energética” como “la manera más rápida y fácil de reducir nuestra huella de carbono”. Ése será, continúa, el elemento central de la estrategia de la administración estadounidense contra el cambio climático. Asegura, asimismo, que la eficiencia energética es tan importante para reducir las emisiones de CO2 como las energías alternativas y más fácil de lograr a corto plazo.

Sigue leyendo