AS I SEE IT
MARIANNE HERON
Clouds can put a damper on life can’t they? Remember the deluge they dumped on the Electric Picnic this summer? And just think of the number of times in this rainy country of ours we pray for clouds to stay away from a special event. But there is another way of looking at the cottonwool vapour that floats above us: Ireland is a paradise for cloud spotters.
Enjoying dinner in the garden in late summer I could see four different types of clouds backlit by the evening sun. They were high lacy cirrostratus, made of veils of ice crystals, honeycombs of cirrocumulus, wispy lines of contrails left by air traffic and low fluffy cumulus, the kind that saints and cherubs sit on in paintings. The high clouds were moving in a different direction from the lowest ones, demonstrating the way winds vary at different altitudes.
One man who set out to change our attitude to clouds is Gavin Pretor–Pinney, author of the bestselling ‘The Cloud spotter’s Guide’, who founded the Could Appreciation Society. Within a year there were 1,800 members in 25 different countries and there are now more than 50,000 members.
Cloud appreciators believe that clouds are unjustly maligned and that life would be immeasurably poorer without them. They view clouds as poetry in motion and practice pariedolia, that is recognising shapes in the ever -changing cloud forms.
The Irish Cloud Appreciation Society (TICAS), founded by Hans Wieland Sally McKenna in 2010, reported an uptake in cloud-spotting enthusiasm during the pandemic.
Ireland’s mobile weather system can make it an excellent place for watching clouds in motion and for seeing the layers of clouds associated with frontal systems. Ireland ranks 16th out of 76 countries for cloud innovation on the Global Cloud Eco system Index.
The western coast can be especially good for watching approaching layers of cloud heralded by wispy Cirrostratus clouds, often mistakenly associated as a sign of fine weather. It may be temporarily fine, but these high clouds mean deterioration in the weather is on the way and they will be followed by Altostratus and Nimbostratus rain clouds.
Surprisingly clouds were only classified 200 years ago by British amateur meteorologist Luke Howard who divided clouds into 10 basic groups with various species within those groups. These can be sub-divided into three groups: low clouds which start below 6,500 feet, Cumulus, Cumulonimbus, Stratus (those nasty featureless blankets of cloud) and Stratocumulus , middle altitude clouds, Altocumulus, Altostratus and Nimbostratus between 6,500 and 23,000 feet and the high altitude clouds Cirrus, Cirrocumulus and Cirrostratus between 16,500 and 45,000 feet..
Apart from the occasional fantasy about riding on those cotton wool clouds (Cumulus) or admiring the towering cauliflower shapes of thunderclouds (Cumulonimbus) I was clueless about clouds. Now I am a total convert to clouds and their amazing nature.
Can you believe that the water droplets in a medium sized Cumulus weigh about as much as eighty elephants (one elephant equals about seven tons), that mature a Cumulonimbus thundercloud can grow taller than Mount Everest, The biggest of these formed in the tropics contain energy the equivalent of 10 Hiroshima bombs. Clouds are also good weather indicators, knowing what type they are and what they are up to can help you read the weather.
Some clouds are formed of droplets of moisture, the more droplets the denser they appear, while others like high altitude Cirrostratus are made of different kinds of ice particles which appear to be white or milky. The droplets in the water vapour of clouds have to reach a certain size before they fall to the ground and in order to grow they need some kind of nucleus to collect around. When they are between one to five millimetres across they reach precipitation point and come to earth as rain.
Clouds are formed in a variety of different ways: puffy cotton wool Cumulus clouds take shape due to convection, where rising plumes of air known as thermals carry warm moist air upwards into cooler air where it condenses. Mountains and hills cause orographic clouds which form where air is forced upwards to pass over them, like Table Mountain’s famous tablecloth.
Once you start to appreciate clouds there is no end to the possibilities: from simply lying on your back on the ground and admiring the passing parade to collecting clouds in various forms.
To me a sky without clouds is like a face without expression, clouds — leaving out boring old stratus — really do have a silver lining.
