In Koppens's classification of climates, Cs refers to

Analyze the question: Köppen's system uses letters to code climate types. You are asked what "Cs" stands for.

Explain the concept: Köppen's letters work like this:

• A = tropical climates (hot all year)
• B = dry climates (BS = steppe, BW = desert)
• C = warm temperate (mild) climates
• D = cold/snow climates
• E = polar climates

The second letter gives the rainfall pattern:

• f = rain all year
• w = dry winter
• s = dry summer
• m = monsoon

Solution:

• Cs = C (warm temperate) + s (dry summer). That describes hot, dry summers and mild, wet winters, which is the Mediterranean climate. It is found around the Mediterranean Sea, in California, central Chile, the Cape region of South Africa and southwestern Australia.

Checking the other options:

• A. Steppe is BS, a dry climate, not Cs.
• C. Tropical Monsoon is Am.
• D. Tropical Continental (Sudan type/savanna) is Aw.

So the correct answer is B. Mediterranean.

Exam tip: Remember "C-s = Cool, with Summer drought" or "Cs = Constant Sun in summer." The "s" always means a dry summer, and only the Mediterranean climate has that pattern with mild temperatures. Also remember that Aw = savanna and Am = monsoon.