Scientists set forth proposals to tame climate

Scientists from 12 academies round the world have met in Tokyo to issue a statement on the inevitable long-term rise in temperature. Their forecast is that in the next 20 years, global temperatures will rise by 0.2-0.4 degree centigrade. The consequences of global warming will be felt worldwide. Polar icecaps will continue to melt and the world's oceans will erode coastlines still further. The academics assessed the scientific aspects of global climate change, due to be discussed by the upcoming G8 summit in Toyako, Hokkaido. This will be a G-8 plus 5 summit involving China, India, South Africa, Brazil and Mexico. Representatives of these five nations participated in drafting the statement on climate change. The decision to expand the summit format was logical as China now ranks second after the United States in industrial emissions, and the other four countries are also notorious for their high pollution levels. The scientists called on world leaders to minimise the threat of climate change, stressed the need for urgent action to clarify the causes of this process and set forth proposals to "tame" the climate.Yury Izrael, director of the Institute of Global Climate and Ecology at the Russian Academy of Sciences, who co-authored the statement, told RIA Novosti that the document mostly aimed at enhancing climate-stabilisation measures, outlined ways of adapting to the situation and stipulated a transfer to a low-carbon society. He said less carbon-intensive energy sources and the energy-preservation principle had to be introduced. Japan, which will host the G-8 summit, has invented a production process making it possible to cut toxic emissions by 70 per cent by 2050. However, Mr. Izrael said this would not solve the climate change problem even if all industrial giants followed suit."To stabilise the climate, we must reduce toxic emissions down to the Earth's natural absorbing capacity. The planet can now absorb less than 50% of toxic emissions," he said. "This means that we cannot achieve any short-term results in this sphere." Mr. Izrael said direct efforts to fight greenhouse emissions held little promise. Scientists have not yet assessed the impact of greenhouse gases on the global climate. At any rate, state-of-the-art industrial technologies are not the only way to fight global warming. This costly programme will take several hundred years and many millions of dollars to implement. The G-8 plus 5 academic meeting also focussed on other factors influencing global climate change. "We must have different 'weapons' for fighting climate change and stabilising the climate, and have to use the most effective ones," Mr. Izrael said. For instance, geo-engineering technologies can alter the Earth's albedo, or reflecting power. According to scientists, young and old trees have different albedo levels. Young trees actively detonate carbon needed for their growth and development, while older trees either absorb little or no carbon at all. Consequently, new forests must be planted regularly to preserve a stable climate. Moreover, we must care for old forests, protecting them from wildfires and implementing well-thought-out tree felling programmes.The Tokyo statement said it was necessary to intensify biological processes in the world's oceans. For instance, plankton, the perennial inhabitant of the seven seas, requires huge amounts of carbon dioxide for further growth and should therefore be planted en masse with special biotechnologies.It is also possible to build orbital solar-ray reflectors. This project may eventually prove less expensive than the costs of global warming. The statement called for developing and promoting Carbon Content Sequestering (CCS) technologies for accumulating, storing and extracting (sequestering) fossil-fuel carbon. This primarily concerns coal, which will remain a major source of energy for the next 50 years. All surplus carbon could be stored under the ground or dumped into the sea.Mr. Izrael is an active supporter of the so-called optimal scenario aiming to change the meteorological solar constant by spraying fine dispersed aerosols of sulphuric acid and other substances into the lower atmosphere at 12-16 km altitudes. This will decrease sunshine reaching the Earth's surface and reduce the temperature in the troposphere by the required number of degrees, serving as an instrument of climate change. In 1974, Mikhail Budyko, member of the Soviet Academy of Sciences and author of the global-warming theory, proposed the aerosol-spraying method for increasing natural atmospheric layers. It is a well-known fact that after volcanic eruptions, surface temperature is reduced over vast areas because natural aerosols block sunshine and bring temperature down.Sulphuric acid aerosols could be sprayed from specially-equipped planes. According to Mr. Izrael, this is an optimal and inexpensive scenario in case of fast global warming. It would be possible to change the situation in 12 months or several years at most. Right now, a group of climatologists headed by Mr. Izrael is preparing to conduct an experiment to assess the impact of sulphuric acid aerosols on temperature fluctuations in some Russian areas.However, the method has some drawbacks. For example, the stratosphere must be sprayed regularly because sulphuric acid aerosols will eventually drift to the ground.But their amount is a thousand times smaller than current greenhouse gas emissions. According to Mr. Izrael, international agreements and joint projects are needed to introduce the aerosol-spraying method. "We have to accomplish this objective because climate remains a major problem and a hard-to-solve social phobia." — RIA Novosti

The Hindu, 6^th July,2008