¿El año en el que el mundo despertó?

Fuente: The Guardian
Comentario: Tenemos nuestras serias dudas de que realmente haya despertado. Ahora bien, es cierto que se habla cada día más del tema. ¿Serán los remordimientos de conciencia?

The year the world woke up

Climate change In 2006, the public, politicians and industry have all shown significant signs that tackling global warming is on the agenda after scientific studies showed the pace of change gathering speed. John Vidal reports

Not before time, the west awoke in 2006 to the vast economic, political and social implications of climate change - and twigged that it presented as many opportunities as threats to humanity. As temperature and rainfall records tumbled, and unseasonal, intense heatwaves, droughts and floods struck many countries, local and national politicians scrambled to beef up their green policies and credentials, some businesses found they could make a packet from trading carbon, and a broad-based global social and ecological movement emerged, linking climate change to social justice, as well as to poverty and lifestyles.

A plethora of scientific reports underpinned the global phenomenon throughout the year, which was officially the warmest ever recorded in Britain and the sixth warmest the world has known. It was, globally, a tad cooler than 2005, the hottest ever, but it continued a trend: the eight hottest years ever recorded have been in the last 10 years.

A succession of alarming reports came out. James Lovelock, the British scientist who devised the Gaia theory - that living organisms affect the environment - forecast planetary wipeout; government studies showed that Australia, in the middle of a "1,000-year" drought, would get even hotter and drier, and that worldwide crop yields would decrease. The Gulf Stream, which warms northern Europe, was found to be slowing, the tundra to be melting faster than previously thought, and satellite images showed that major rivers of Africa are carrying significantly less water than before. Monsoons were even more erratic across the Indian sub-continent, Arctic sea ice was predicted to disappear - along with polar bears - by 2040, and almost all the world's glaciers, in many cases providing water for cities, were confirmed to be in retreat.

As the decline of winter sports in Europe was being contemplated, scientists became increasingly confident about linking the evident warming to manmade emissions. Others, previously quiet, spoke loudly: Sir David Attenborough, bishops and celebrities all called on people to make climate change the great moral issue of our times. The few remaining contrarians in the scientific and political establishment became increasingly isolated.

Most serious issue

In Europe, polls showed climate change to be the second most important issue, behind unemployment, with 93% of people wanting action taken. Spurred by Tony Blair's insistence that it was the "most serious issue facing mankind", and chief scientist David King's warning that global warming was "more dangerous than terrorism", the Tory leader David Cameron launched an immediate and serious pitch for the mainstream green vote with a trip to the Arctic. Labour, worried, astutely appointed David Miliband as the new environment secretary in place of Margaret Beckett. Within months, he had called for a complete rethink of national politics, saying that the environment movement today was as significant as the unions had been to the rise of Labour 100 years ago.

As the political and lifestyle debate spilled into all areas of British life, the government was criticised for doing little. Latest UK carbon dioxide figures showed emissions rising in 2005 to the highest level they had ever been under Labour. Other figures showed that UK greenhouse gas emissions fell slightly by 0.3m tonnes to 656m tonnes of carbon dioxide equivalent between 2004 and 2005, but that net emissions of C02 increased - the third consecutive annual rise.

The long-awaited climate review in March talked of conservation and technological change, but was slammed for its perceived timidity. Meanwhile, the Department for Transport (DfT) was singled out for promoting a huge growth in airport and road capacity, and Gordon Brown was criticised for barely addressing the issue in successive budgets.

Only the Stern review of the economics of climate change brought the Treasury any respite. It broke fresh intellectual ground by arguing that the presumption of economic growth was no longer valid in view of climate change, and that not addressing it could lead to an economic upheaval on the scale of the 1930s' Depression. For the first time, a figure was put on the pollution costs of carbon emissions: £50 a tonne.

But the scale of what needed to be done was constantly ramped up. A report from the Tyndall Centre for Climate Change Research at Manchester University factored in aviation and shipping emissions for the first time and concluded that the UK needed a 90% cut in emissions, not 60%, by 2050. At current rates, the government will only just meet its mandatory Kyoto target of a 12% cut in greenhouse gas emissions by 2012.

On a global level, the situation was found to be worsening rapidly. Last month, the Global Carbon Project said a record 7.9bn tonnes of carbon passed into the atmosphere in 2005, compared with 6.8bn tonnes in 2000. Indeed, the growth rate of CO2 emissions from 2000 to 2005 was more than 2.5% a year - in the 1990s it was less than 1% a year. The finding parallelled figures released by the World Meteorological Organisation, showing that the rise in atmospheric concentrations of CO2 had accelerated in the last few years.

The US went ahead with plans for over 150 new coal-fired power plants, and China for some 550. The International Energy Agency forecast that China's expanding use of coal will lead it to surpass the US as the largest emitter of CO2 by 2009. China responded by announcing targets of 16% of all energy from renewables by 2020.

But even as many environment groups said the world had only a decade or more to stabilise emissions before potential runaway climate change set in, those who could really influence change moved slowly; 160 countries meeting in Nairobi could not even agree what to do when the Kyoto agreement runs out in 2012.

However, the global financial community at last stirred. Wall Street investors, insurance companies and pension fund managers, who between them manage trillions of dollars in assets, were pushed throughout 2006 to re-evaluate their exposure to climate change and the risks of doing nothing. US insurance companies found that $2 trillion in real estate was at risk from future storms in the coastal communities of Florida alone.

Worsening poverty

Crucially, a popular movement emerged, driving the social and financial agenda in all developed countries. In the UK, most large anti-poverty and development groups finally grasped the implications of climate change for poor countries. As partner groups in Africa, Asia and Latin America reported that it was already worsening poverty, some of the traditional barriers between environment and development groups disappeared.

Meanwhile, many religions and faith groups discovered the environment. The Church of England took steps to reduce its footprint, and the powerful evangelical movement in the US pressured President Bush to address "creation care". Muslims, Jains, Buddhists, Catholics, the Greek Orthodox church and other faiths all urged their followers to take action.

The growing concern was reflected in Britain in early November when 20,000 people - possibly the largest environment protest ever staged in Britain - marched in London and elsewhere for action. Direct action groups such as Plane Stupid emerged and anti-airport expansion community groups began to work together. Britain's heaviest carbon polluters were identified and 4,000 people camped outside Drax power station in Yorkshire. Greenpeace stopped work at Didcot, and others stormed 4x4 car showrooms.

Increasing anger was directed at the government, which appeared to be following a business-as-usual agenda with transport, while arguing that emissions trading would suffice. In October, Oxford University's Environmental Change Institute warned that it would be impossible to meet the UK's 60% carbon reduction target by 2050 without curbing aviation growth - yet a few weeks later the DfT backed plans to massively expand most of Britain's airports.

By the end of the year, government was publicly more committed than ever to addressing climate change, but privately in semi despair at the mismatch between intention and reality and how long it was taking to achieve a low carbon economy.

Creciendo la temperatura y el nivel de los océanos

Fuente: IPS
Comentario: No se trata de algo muy distinto de lo que se viene diciendo frecuentemente...


Oceans Warming and Rising

BERLIN, Dec 21 (IPS/IFEJ) - Ocean levels will rise faster than expected if greenhouse gas emissions continue to rise, a leading German researcher warns.

Using data from the U.S. National Aeronautics and Space Administration (NASA), Stefan Rahmstorf, professor of physics of the oceans at the University of Potsdam near Berlin estimates that sea level could rise 140 cm by 2100.

Rahmstorf, member of the German Advisory Council on Global Change, is considered a leading European researcher on global warming and its effect on oceans.

"The semi-empirical model we used to process NASA data showed a proportional constant sea level rise of 3.4 mm per year per degree Celsius," Rahmstorf told IPS. "Then we applied this constant proportionality to future earth surface warming scenarios of the Intergovernmental Panel on Climate Change (IPPC), and came to estimate that by the year 2100, sea level could rise between 50 and 140 cm above the level measured in 1990."

Through the 20th century, global warming led to an average 20cm rise in sea level. But most computer models of climate change used at present significantly underestimate sea level rise, Rahmstorf said. "Future projections of sea level based on these climate models are therefore unreliable."

Currently, sea level is rising at three cm per decade, faster than projected in the scenarios of the IPCC Third Assessment Report, Rahmstorf added.

The IPCC, an intergovernmental team of scientists carrying out a wide range of research related to climate change, was established in 1988 by the World Meteorological Organisation and the United Nations Environmental Programme. The IPCC aims to assess scientific, technical and socio-economic information relevant for understanding of climate change, its potential impact, and options for adaptation and mitigation.

Scientific research has found that industrial activities have produced greenhouse gas emissions considerably higher than levels observed before the industrial revolution.

Concentration of carbon dioxide (CO2), the most potent of greenhouse gases, has risen from about 280 parts per million (ppm) in the atmosphere in the year 1750 to about 380 ppm today.

This rise is primarily due to the burning of fossil fuels, and to a lesser extent, deforestation. Scientists estimate that if the present emissions trend continues, the atmosphere could heat up by about five 5 degrees Celsius by 2100.

Studies by the Potsdam Institute for Climate Impact Research suggest that this would roughly be the temperature difference between an ice age and a warm stage. But while the rise of average temperatures by some five degrees between the last great ice age and today took 5,000 years, the new global warming would need only 100 years.

Rahmstorf acknowledged that forecasts of global warming and its effects on sea levels continue to be marked by uncertainty. "The fact that we get such different estimates using different methods shows how uncertain our sea level forecasts still are," Rahmstorf told IPS.

A major reason for the uncertainty is the behaviour of the large ice sheets in Greenland and Antarctica.

A likely consequence of a massive melting of the ice masses on the North Pole could be the breakdown of the North Atlantic Current (NAC). The NAC is the northern extension of the Gulf Stream, and constitutes a warm water current flowing between Britain and Iceland. This has considerable impact in moderating the North European and Scandinavian climate.

"One critical factor for the continuation of this current is the amount of fresh water that enters the Northern Atlantic region in the future," Rahmstorf said. "This will depend in large part on the speed at which Greenland's ice sheet melts."

Rahmstorf, who earlier this year co-authored a research paper titled 'The Future Oceans -- Warming Up, Rising High, Turning Sour' said that reliable prediction on the risk of a total stoppage of deepwater formation in the Northern Atlantic is not possible given present knowledge.

But he pointed out that experts have evaluated that risk at more than 50 percent if global warming is between three and five degrees.

Rahmstorf said greenhouse gases emissions are also increasing the acidity of oceans. "In the atmosphere carbon dioxide does not react with other gases, but in the ocean it dissolves, contributing to the acidification of seawater," Rahmstorf said. This acidity is a serious threat to marine biodiversity.

"There is a good chance to avoid such dangerous climate change if global warming caused by human activities is limited to two degrees in the coming decades," Rahmstorf said.

(*This story is part of a series of features on sustainable development by IPS - Inter Press Service and IFEJ - International Federation of Environmental Journalists.)

¿Vamos hacia una nueva era glaciar?

Fuente: Teleobjetivo
Comentario: ¿Quedará todo ésto en tablas al final?

Eso es lo que afiman muchos investagores; el último, Khabibullo Abdusamatov, responsable de investigaciones especiales en el Observatorio Astronómico de Pulkvo. Este investigador afirma que en el 2012 comenzará un descenso de las temperaturas que desembocará en una nueva era glaciar.

En este artículo, el investigador ruso afirma que empezaremos a observar un descenso de temperatura entre el 2012 y el 2015, que culminará entre el 2050 y el 2060 dando paso a una era glaciar que prevee durará unos 60 años. La causa de este descenso de temperatura será un cambio en el ciclo solar, que no tendría nada que ver con la actividad humana

Teorías sobre el cambio climático hay muchas; el atribuirlo a un ciclo solar no es una idea nueva; de hecho, es una de las principales bazas de los opositores al protocolo de Kioto. La evidencia mas importante la tenemos en la llamada pequeña edad de hielo; un periodo que se extiende desde mediados del S.XIV hasta mediados del S.XIX, durante el cual las temperaturas fueron anormalmente bajas. No hubo ninguna explicación para este fenómeno hasta que el astrónomo Edward Maunder, tras estudiar los archivos históricos de las observaciones del sol, detectó que durante la pequeña edad del hielo el Sol había presentado un número anormalmente bajo de manchas solares, destacando el periodo 1645 a 1715, durante el cual no había observado ninguna mancha (este periodo se conoce como el mínimo de Maunder); da la casualidad de que uno de los años mas fríos de la pequeña edad de hielo fue 1650.

De todas formas, la teoría de la actividad solar no es la única que predice una próxima era glaciar; en los últimos años se ha formulado una teoría que, por paradojico que parezca, predice que el efecto del calentamiento global será una era glaciar. La respuesta a esta aparente contradicción hay que buscarla en las corrientes marinas.

Como podemos observar en el dibujo, las corrientes llevan las aguas cálidas del trópico a latitudes mas elevadas, evitando así que estas zona se congelen; en las zonas polares, el agua se enfría y eso la empuja de nuevo hacia el sur (las corrientes cálidas van por la superficie, las frías por el fondo marino). Como hemos dicho, una de las funciones básicas de esta corriente es calentar las latitudes mas elevadas, por lo que si dejara de fluir, estas zonas se congelarían; de hecho, muchos climatólogos atribuyen las eras galciares a un mal funcionamiento de estas corrientes.

¿Como puede el calentamiento global provocar una era glaciar? Muy simple; el calentamiento está provocando que los hielos polares se derritan, liberando una gran cantidad de agua dulce que interfiere en el funcionamiento de las corrientes y les hace perder fuerza. De momento no notamos su efecto, porque el calentamiento también provoca que la temperatura de estas corrientes sea mayor, lo que compensa la pérdida de fuerza; pero cuando los hielos polares hayan retrocedido lo suficiente, las corrientes se detendrán, lo que provocará una repentina caida de las temperaturas.

¿Quien tiene razón? Lo mas probable es que todos tengan una parte de razón; los efectos de la acción humana sobre el entorno saltan a la vista, como también son obvios los efectos de las corrientes marinas y el Sol; la clave está en determinar los porcentajes de responsabilidad de cada uno de estos elementos; en cualquier caso, una cosa está clara, nuestro conocimiento de como funciona el planeta es aún muy pequeño.