Reply to article: Prof. Joanna Haigh attempts to fool Telegraph readers about Boris Johnson’s climate views

Letter – The Telegraph – 23rd January

SIR – As a professor of atmospheric physics, at Imperial College London, I’m delighted that Boris Johnson maintains his interest in weather and climate (“It’s snowing, and it really feels like the start of a mini ice age”, Comment, January 21), but he should be wary of drawing generalised conclusions from his observations. He suggests that the cold weather is due to declining solar activity – but the sun is more active now than it has been since 2009, and about the same as it was in 2004 and 1998. What we have is the lovely variability of British weather sitting on top of a long-term global average warming due to greenhouse gas increases. This is not an issue of opinion, but one of basic physics.

We don’t need to invoke mysterious solar particles to understand long-term trends.

Professor Joanna Haigh