The Köppen–Geiger climate classification made simpler (I hope so)

[Pixie]

I've read the whole thing, it is helpful indeed Azelor.

Being a science teacher and an amateur climatologist/geologist (in fact, an amateur world-builder), I can follow all of it pretty easily. Dunno how less science savvy folks will manage it, but it doesn't seem complicated.
I think it is a very valuable add-on to the tutorial I (we) are currently building.

It made me think of one more climate map that would be very useful: a cross-reference between rain pattern and temperature, to make a two-colored map separating areas where evapotranspiration is greater / lower than precipitation. This could perhaps be helpful (do you think it would be helpful?)

Picking up the word usage in my tutorial, what do you think of this?
Lower precipitation than evaporation (DRY seasons)
Very Hot + Moderate/Low/Dry
Hot + Low/Dry
Warm + Dry
Roughly equal precipitation to evaporation (MODERATE seasons)
Very Hot + Wet
Hot + Moderate
Warm + Low
Mild + Low
Cold + Dry
Very Cold + Dry
Higher precipitation than evaporation (WET seasons)
All remaining combos

[Azélor]

I've read the whole thing, it is helpful indeed Azelor.

Good to know.

Were you considering a map or some info graphic like this one : http://powerfulinfographic.com/wp-co...parency-11.jpg
I don't know about the idea. There is a relation between temperature and minimum precipitations to avoid desertification. Did you know that the Sahara would need between 3000mm and 6000mm of rain per year to become a moderate climate similar to Spain? That's a lot of water and it's just the minimum.

There is a part in the guide where I talk about yearly precipitation not seasonal. The problem with the classification is that it compares the driest month with the wettest without taking in consideration if the driest month is really dry. Sometimes, it's not the case. It's considered dry only because the wet month receive a lot more rain. So the letters s and w are more or less valuable here. At the equator, at least we know that under 60mm it's considered dry.



edit : this ! http://en.wikipedia.org/wiki/Aridity_index

and this : http://upload.wikimedia.org/wikipedi...dity-index.png

I'm now using this from the Trewartha wikipedia page: BW and BS mean the same as in the Köppen scheme, with the Köppen BWn climate sometimes being designated BM (the M standing for "marine"). However, a different formula is used to quantify the aridity threshold: 10(T − 10) + 3P, with T equaling the mean annual temperature in degrees Celsius and P denoting the percentage of total precipitation received in the six high-sun months (April through September in the Northern Hemisphere and October through March in the Southern).
If the precipitation for a given location is less than the above formula, its climate is said to be that of a desert (BW); if it is equal to or greater than the above formula but less than twice that amount, the climate is classified as steppe (BS); and if the precipitation is more than double the value of the formula the climate is not in Group B. Unlike in Köppen's scheme, no thermal subsets exist within this group in Trewartha's, unless the Universal Thermal Scale (see below) is used.