Michael McCarthy: Enjoy cold winters while they last

Nature Notebook

It is the winter solstice on Sunday, when the days begin to lengthen once again, albeit imperceptibly, and the great cycle of rebirth starts once more, even if the two harshest months are still ahead of us. My spirits are always lifted on 21 December because I feel that a corner has been turned and the warmth and the new life are on the way – but this year has been different: I have been positively enjoying the winter cold.

If you follow the climate change agenda and you accept the science, you will need no convincing that cold winters in Britain will fairly soon be a thing of the past. Indeed, for the past 20 years, winters have been getting steadily warmer, with noticeable results in the natural world. Many resident garden birds which are vulnerable to freezing weather, such as wrens, have been enjoying an enormous population boom, while numbers of badgers are also soaring because they have been able to dig in unfrozen ground for their main food, earthworms, all winter long. This is very likely the reason why hedgehog numbers are plummeting, because badgers eat all the hedgehogs they can find (although, curiously, no one seems to be making much of a fuss about it).

The reason we have had a chilly December is probably La Niña, the climate phenomenon which occasionally sees the waters of the tropical eastern Pacific Ocean turn very cool, affecting the global climate in turn. But the current La Niña is now weakening and next year (and certainly from 2010) the super-computer climate models show global warming taking off once more.

So I have been relishing the sharp cold air on my face with a strong sense that this is the natural order of things, but there may not be much more of it. Meanwhile, I find I am more and more drawn to the carol "In The Bleak Midwinter", with its frosty wind, earth hard as iron and water like a stone, and I find myself longing for snow as much as any child does.

Majesty of the sky at night

Snowfall in London makes the most magical transformation of the cityscape, but there is an even more remarkable winter sight in the capital: the constellation Orion, greatest of all the heavenly bodies in the night sky, seen from Waterloo Bridge. If you cross the bridge from north to south, especially on a freezing but clear January evening at about 8pm, Orion the hunter blazes out of the sky in front of you, above the National Theatre and Waterloo station. It is so brilliant that even the light pollution from a million street lamps cannot hide it.