MADAM – Twenty years ago, my wife, daughter and I were on a viewpoint overlooking the foot of the Gross Glockner glacier.

From the road, it was an easy walk down to a point where you could actually touch the face of the glacier. Last year, my daughter took her children to the same place.

The foot of the glacier was not visible, and to reach it and then get back to the coach they had to do an energetic forced march up the valley, passing markers all the way stating the date that the foot had been at that point.

Seeing is believing, they say, and now she is convinced of the reality of climate change. This glacier is not alone in shrinking.

The Wikipedia article on http://en.wikipedia.org/wiki/Retreat_of_glaciers_since_1850 shows that this tendency is universal.

To quote: “Since 1980, a significant global warming has led to glacier retreat becoming increasingly rapid and ubiquitous, so much so that some glaciers have disappeared altogether, and the existence of a great number of the remaining glaciers of the world is threatened.”

Then there is the loss of ice from the Antarctic ice cap.

Between 1992 and 2011, the Antarctic ice sheets overall lost 1,350 giga-tonnes (Gt) or 1,350,000,000,000 tonnes into the oceans, at an average rate of 70 Gt per year (Gt/yr).

These estimates equate to an increase in global-average sea levels by 0.19 mm/yr. Ice shelves on both sides of the Antarctic Peninsula have collapsed in the last quarter of a century, and others are in trouble.

The attitude of climate change deniers is irresponsible in the extreme, and the policies of UKIP, as exemplified by Caroline Stephens’ letter, (SNJ March 26) are particularly so.

Scientists are almost uniformly convinced that present climate change is caused by human activity, and they provide evidence to support that view.

On the other hand, sceptics exist on chop logic and assertion.

Christopher Monckton, leader of UKIP in Scotland, for example, told an audience in the US, that the aim of a proposed UN climate change treaty on climate change was to “impose a communist world government”.

Roger Plenty, Stroud