Pollution killed the radio star

Signs of climate change can also come through mute radios

Published: Thursday 30 September 2004

-- SOMETIMES, no news is worse than bad news. You can ask millions of old-fashioned citizens in south Asia -- mostly from the lower strata of the consumer ladder and some others who can't give up an old habit -- who still tune in to BBC Radio or Radio Sri Lanka (Radio Ceylon, if you were around in the heyday of this brand). Their archaic radio instruments are capable of catching shortwave signals; they are yet to catch on the FM radio potpourri. These people are in a jam because shortwave signals are gettig increasingly unclear. They are yet to get an important bad news.

We don't know if Guglielmo Marconi, the Italian who made radio transmission possible back in 1895, will pardon us for failing him so miserably. Since his first trans-Atlantic radio transmission in 1902, the operating principle has remained unaffected by the media revolution: the ionosphere reflects radio frequencies below 10 megacycles. A team at the Indian Instutute of Tropical Meteorology spent five years studying the ionosphere. After analysing records of global temperature and weather patterns of the past 30 years, they concluded that the ionosphere's shrinking, and this is inhibiting reflection of shortwave radio frequencies. (see Fading out) Why is it thinning down? Due to a rapid temperature decrease (15C in 30 years) in the ionosphere.

To visualise the implications, think of a mime artist suffocating from an imaginary contraction of space. Then tell yourself: "Our atmosphere's shrinking." In real time, this shrinking will create an 'atmosphere drag', pulling our satellites earthwards. It is bound to affect lower atmospheric behaviour and, hence, weather. Blame rising levels of air pollution and increasing emissions of greenhouse gases. In the months and years to come, we are likely to come across studies that negate this finding with vehemence. Be prepared.

Bad news is actually pouring in from all directions. The ordinary people can't make sense of the terms statesmen and scientists use. Global warming? Climate change? Call it what you may, things are changing. And they are affecting us. Elsewhere in this issue of our magazine, readers will find our request for their perception of how the weather's changed in their region. It's a bit tricky. The signal could be early flowering or late rain, short winter or repeated crop failure, a sudden increase in boat production or the need to buy additional winter clothing. In the intricate world of climate change, somebody's loss can be somebody else's gain. If Marconi's signal is getting weakened by a thinned ionosphere, what's happening to televisions signals?

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