|
Wordsworth
was captivated by clouds....
I
wandered lonely as a cloud
That floats on high o'er vales and hills
When all at once I saw a crowd
A host, of golden daffodild;
Beside the lake, beneath the trees,
Fluttering and dancing in the breeze.
Altocumulus
stratiformis perlucidus and cirrus spissatus verbratus may be
a mouthful but they are both identified by a code number which
allows meteorologists to identify them at a glance. |
| Richard
Angwin |
...and
Turner and Constable spent many years studying and painting them.
Clouds
have always fascinated mankind but until fairly recently they were
just 'essences' floating in the sky.
But
this year marks the 200th anniversary of the first attempt to describe
all the clouds we see in the sky. And it is a system that we still
use today.
Luke
Howard (1772-1864) was an English chemist who also had a fascination
with the weather. Although he was not a scientist, he was a keen
observer of the weather since his schooldays and he made many contributions
to the development of meteorology. For this work he was made a fellow
of the Royal Society in 1821.
In
1802 Howard published his 'Essay on the Modification of Clouds'.
In this he recognised that there were four main categories of cloud.
These
categories are still in use today, although the there has been considerable
refinement since Howard's day.
| Cloud
types |
| Cumulus |
Lumpy
clouds with flat bases and cauliflower-shaped tops, from the
latin for 'heaped' |
| Stratus |
Extensive
sheets of layered cloud |
| Cirrus |
Wispy,
curly clouds |
| Nimbus |
Systems
of clouds from which rain falls |
There
are now ten of these main categories of clouds as well as many different
species and varieties. This allows us to describe the clouds very
precisely.
 |
| A
fabulous formation |
Altocumulus
stratiformis perlucidus and cirrus spissatus verbratus may be a
mouthful but they are both identified by a code number which allows
meteorologists to identify them at a glance.
The
question then arises, “Do all these obscure names really matter?”
The answer is yes! Each cloud is an indicator of different things
happening in our atmosphere.
Whether
the air is moist, rising, descending, unstable or turbulent. And
each one gives us a clue as to what the weather has in store.
by
Richard Angwin
|
