h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: Cloud Types and their Significance - A1124911
Author: Tony C - U235771

Weather forecasting for the lay-man. Just a few tips on cloud-type observation and a few hints on the type of weather you may expect from these clouds.

Tony C

Hi, Tony C!

This looks very interesting, and I hope to give it a more thorough read in the next couple of days.

In the meantime, one thing caught my eye, about cirrus clouds:

'it has often been suggested that they can serve as the indicator that a storm is approaching.'



As a suggestion about ordinary cirrus clouds, I find that really odd! It's almost on the lines of the old saying 'if you can see the mountains, it's going to rain; if you can't see the mountains, it's raining'.

Azara

You've mentioned "Glider pilots love these formations as they tend to promote lift." - I think they actually have thermals underneath them, and you might like to use that word.

I like it - but I'll look it over and make further comments later.

n1W7

This looks like a really interesting article. There are a few spelling mistakes in it though. It might be worth putting it through a spell checker if you have one. I spotted it's, potion, comming and a few others.

I don't think you need the first bit to be in bold. Most people seem to start with an introduction like that but leave it in normal text.

The bit about the intro in bold applies to your other entries as well, Tony C, but I guess I shouldn't really be posting that here.

Apart from the point that the bold isn't in the "house style" I have nothing to say, other than this is a good entry, and I'm glad you've decided to contribute to the Edited Guide.

Hi again, Tony C

What's a tropopause? It might benefit from an explanation.

Typos:

comming > coming
areound > around
govenrment> government
indentifaication > identification
an dpossibly > and possibly

Thanks all for your comments. I've done the following:

Added a definition for tropopause
Spell checked
Fixed the bold bit at the beginning
Mentioned thermals
Made a few other minor gramatical corrections

I hope it's getting better, and more like a Guide entry...

Tony C

It's certainly looking good on a very very very small note there's no reason to add the header "introduction" but considering it would take about 10 seconds for the sub editor to fix that, I feel very pedantic posting it.

Is this article as finished as it can be now or do you guys have any more to add?

Tony C

A great idea for an entry, but needing quite a bit more work I think. Here are a few suggestions:

"...it is entirely possible for the casual observer to predict what kind of weather to expect over the coming hours."
And days.

A slightly longer description of how clouds form would be beneficial. Nothing too involved, something along the lines of
"Clouds are formed when air rises, either as a result of heating by the sun or by being forced upwards as it travels over hills or mountains. Through the process of cooling, the water vapour within the air mass condenses into water droplets."

I'm ready to be corrected on this, but I'm not sure that it's correct to say that it 'reaches saturation point' - the amount of water vapour within the cloud doesn't increase. You could say that it reaches *dew point*, but then you've just got another term to explain to those who don't know what dew point is.

I think that by including something like that, you could replace the paragraph "Clouds are formed through a number of actual physical processes, but the scientific reason for their formation is always the same:" which is a bit nebulous (no pun intended). It's always good to avoid rather vague statements like 'a number of actual physical processes' if those processes aren't going to be either mentioned or described.

"Clouds are the culmination of millions of water droplets and/or ice crystals, held up in the atmosphere by the turbulent, convective movement of the surrounding air."
That's not grammatically or meteorologically correct. You could say 'Clouds are comprised of millions...', or 'A cloud is a formation of millions...', or even 'Rising air culminates in the formation of clouds as millions of droplets of water condense.'

It's not necessarily the *surrounding* air which holds up the water droplets and ice crystals - convection is also going on within the clouds themselves, keeping them aloft, and as already mentioned, clouds aren't always formed by 'convective movement'.

I don't have time right now to go through the rest of the entry - I'll have to come back to it later.


Scout

Hi and thanks for your input.

Ive made some ammendments to the entry and have corrected a couple of your points. The dew point and the saturation point are by-and-large the same until you look right down at the actual difference between the actual temperatures. The release of specific latent heat when the water condenses makes the two slightly different, but for this sort of article it isn't necessary.

Ho hum

Toyn C

Hi Tony C,

Looking good

I was going to say the same as Gosho: maybe you could mention just a little bit of what causes the moist air to be forced up over the dry air.
Warm front: Warm air rides up over a wedge of cold air.
Cold front: cold air bumps into warm, forcing the latter up and over.
Cold front occlusion: cold front overtakes warm air mass, forcing it upwards, then collides with another (not quite so cold) air mass.
Warm front occlusion: as above except the overtaking air mass is the colder of the two.

The warm front will result in cirrus at first, etc...



Awu

Hi agin TOny C,

Sorry -that's probably too much.
Just a passing note about various combinations of warm and cold air colliding might be enough.

Awu.

Too much or not enough...

What's it to be?

Tony C (slightly perplexed at what way to go)

Didn't intend to confuse

I meant that my first suggestion was probably too detailed.
Somewhere after you say "when the air is forced to rise" maybe you could give a couple of examples of what might cause that to happen.

Awu.

Beneath the heading of 'types of cloud' it would be nice to say a word or two about Luke Howard - the person who initiated the naming system now used, classifying into the four basic types (cumulus, cirrus, stratus, and nimbus). Possibly a linked biographical entry would be good, or failing that a link to an external biography, try this:

http://www.cloudman.com/luke/luke_howard.htm

Pimms

I was always taught that there were four types - the fourth being 'Nimbus' from the Latin for 'cloud' to signify rain clouds.

I was glad to see Pimms mention Howard since we're still using the system he came up with in the early 19th Century.

The beauty of the system being that you can combine any of the names to come up with other types like stratocumulus...

Don't know if there's any truth to this, I read somewhere that one of the early cloud atlases listed 10 cloud types with the fluffiest being the cumulonimbus which might have been the origin of the expression 'on cloud nine'.

You might want to include the Latin translations of all the cloud names too...

You seem to have some but not all.

Cirrus means 'curled'
Cumulus actually means 'heaped'

That's all I guess!

Nice idea for an entry!


- Jimi X

You make mention of nimbus clouds in the various combinations (ie cumulonimbus, nimbostratus) but you don't have a section devoted to nimbus clouds.

The Professor
Societas Eruditorum

The word Nimbus is derived from the Latin word and means quite literally, 'cloud, rain, corona'.

There are no specific individual NIMBUS clouds, instead the term is a prefix or suffix meaning that the cloud type is rain-bearing.

e.g. Cumulonimbus means rain-bearing cumulus!

There you go! A little lecture in naming conventions of clouds
Hope that explains it sufficiently...

Tony C