Monzones en la India

Vie, 26/08/2005

Increasing air pollution and forest conversion in South Asia could potentially lead to a failure of the Indian summer monsoon, suggest researchers at the Potsdam Institute for Climate Impact Research (PIK) in a study exploring the stability of the Indian monsoon. The results of the study appeared in the current issue of Geophysical Research Letters.

Yearly monsoon rains have a huge impact on the lives of people in India. A weak summer monsoon, for example, can lead to poor harvests and food shortages among the rural population – two-thirds of India’s almost 1.1 billion people. Heavier than usual monsoon downpours can also have devastating consequences, as the inundation in India’s capital Mumbai showed in recent weeks.

PIK researchers flagged a mechanism which could lead to a failure of the Indian summer monsoon. The culprit is increasing air pollution with airborne particles (aerosols) over India which is caused by fires, increasing fossil fuel consumption, and alarming evidence of forest clearance. Together, they could lead to intensification of the Earth's brightness, or ‘planetary albedo’, in the region. Odd as it sounds, this would mean less sunlight reaches the surface, causing the temperature over land to decrease. The supply of moist air which feeds the monsoon rains would effectively be cut and, as a result, precipitation would decrease dramatically.

The researchers are cautious about using the model as it is to make any climate predictions. For this, they say, further analysis is needed which considers realistic projections – so-called ‘scenarios’ – of the air pollution, as well as of land-use change in South Asia. Another factor would also have to be considered: rising concentrations of greenhouse gases (GHG).

Rising GHGs in the atmosphere could have the opposite effect on the summer monsoon because they lead to higher temperatures over land and, hence, heavier rainfall. But, without better tools and more research, they cannot determine which one of these two effects will dominate in the end.

Climate change under the EU umbrella
What is the European Union’s take on climate change? For decades, the Union has been an active partner in the world’s battle against negative climate change. Most recently, during the UN Conference on Climate Change in December last year, the EU presented its Emissions Trading System (ETS) which was to be launched the following month. The ETS was heralded as a concrete step towards implementing EU commitments under the Kyoto protocol – to lower greenhouse gas emissions in as cost-efficient a manner as possible.

Leaders discussed how developing countries, including those in South Asia, need support to deal with the effects of climate change. These discussions were followed up at the EU-hosted Green Week last Spring, which was a week of meetings, exhibitions and awareness-raising exercises dedicated to helping Europe ‘Get to grips with climate change’.

On both occasions, the EU committed itself to helping developing countries cope with climate change, which includes support for policies to help mitigate the devastating impacts of floods, desertification and other phenomena hindering development in the poorer regions of the planet. At the UN Conference, the EU said it was keen to start the ball rolling for informal discussions on a future international framework for fighting climate change, especially since the emission reductions envisaged by Kyoto only run until 2012.

The EU’s current Framework Research Programme (FP6, 2002-2006) has set aside a significant sum towards better understanding climate change and air pollution, on the one hand, and desertification and natural disasters, on the other. Numerous projects have been completed in previous research programmes – and are ongoing in FP6 – which help scientists understand more about the environment.