The acid test

It is inescapable that the global climate is likely to be one of – if not the biggest – shaping force on our lives over the next century. Though the debates rumble on between environmentalists and sceptics over whether the change in global weather patterns are man made, governments around the world are already investing huge sums of money in a hope of counteracting the effects. In decades prior to this however, the full extent of the threat of climate change had yet to be realised. Certain signs though had already started to manifest that something was clearly wrong.

One of the prominent early signs of climate change was acid rain. The acid rain effect is formed when gases, such as sulphur dioxide and nitrogen oxides that occur through the burning of fossil fuels, pass through and combine with water vapour in the atmosphere. When this occurs the vapour gains a weak acidic pH level. The vapour eventually turns to rain and falls to the ground with ill effect, raising the pH level of ponds and lakes killing fish, ruining crops, eroding rocks and damaging buildings.

One of the worst repercussions of acid rain is that the most erroneous polluters rarely bear the brunt of the effect. Much of the acid rain that resulted from the UK’s dirty emissions during the 1970s for example fell on Norway rather than here at home. As such, legislation was drawn up across Europe to endeavour in reducing emissions and enforce fossil fuel burning power stations to scrub sulphur emissions from their exhaust fumes. As a result sulphur dioxide outputs have fallen from around four tonnes a year in the UK at the end of the 1970s to around half a tonne this time around.

As a reflection on the improvements made, a report in July given to Defra by the Acid Waters Monitoring Network has examined the impact of acid rain and the results on the whole where not promising. Though the survey of 22 sites across the UK determined that the acid levels of water supplies prone to the effect of acid rain had dropped by 85 percent compared to readings taken 20 years ago. Plant and animal life are however enduring a slow recovery rate. The UK is at least beginning to turn the corner.

This situation will be of some relief to the UK’s property stock. The effect of acid rain on eloquent stone such as marble, limestone and granite is disastrous. Though the pH is only weakly acidic, the repeated effect of rain over the years wears down the rock. Detailed statues become worn while ornate carvings on the side of buildings literally melt away. As a result, many of the UK’s historic buildings have faced costly repair bills to bring details back to prominence.

Yet despite this recovery in the UK, the issue remains central to the world stage. China’s huge industrial expansion in recent years has seen it create deadly quantities of pollutant gases to an extent unseen in the western world. The Air Pollution Index, a safety guide for air quality, recommends that children and the elderly should remain indoors when levels reach 100 and the general public stay indoors at 200. In March of this year, levels in Hong Kong reached over 400.

With other superpowers such as India and Brazil also expected to experience huge rates of industrial expansion over the next decade, the threat of the same effect – or worse – remains present. And this time it could be the UK on the receiving end of it. The return of acid rain may therefore not be so far away.