Clouds sprayed with chemicals to cause rain

PORTUGAL’S drought has become so serious that the authorities have been spraying clouds with chemicals in a bid to bring rain. Two Hercules C-130 planes belonging to the Portuguese Air Force (FA) released two chemical agents into the atmosphere above Coimbra, Castelo Branco and Évora, recently.

Portuguese meteorologists had predicted that the north and central regions of the country were to have experienced rain last week, but, despite gathering clouds, the rain was insufficient.

It wasn’t until Saturday night that substantial rain fell over much of the country, following what has been termed as Portugal’s “worst drought in the past 50 years” and “the driest January in 100 years”.

In fact, rainfall for the entire Iberian peninsular was 20 per cent down on the average rainfall for January.

The planes dropped silver iodide and calcium chlorite, which help atmospheric water vapour condense and fall as rain. The project was a joint venture between the FA and the Institute of Environmental and Meteorological Studies in Lisbon.

Environmentalists from the Portuguese Nature Protection League (LPN) and Quercus stated recently that the chemicals would not have an adverse effect on the environment or pose a hazard to human health. Eugénio Sequeira, a soil specialist and member of the LPN, told Lusa news agency that the chemicals “didn’t cause rain”, but “helped make the clouds heavier by causing water condensation”. The scientist added that “this type of project is not always effective”. C.G.