Which scale is used to measure cloud cover?

Which scale is used to measure cloud cover?

• A. Beaufort scale
• B. Euler scale
• C. Oktas scale
• D. Celsius scale

Answer: (C)

Cloud cover is estimated by judging how much of the sky is shaded by clouds, using the Oktas scale. This scale measures cloudiness in eighths of the sky, from 0 (a completely clear sky) to 8 (a completely overcast sky). In practice, observers note cloud cover in octas or with sky-cover codes like FEW (1–2 octas), SCT (3–4 octas), BKN (5–7 octas), and OVC (8 octas). The other scales mentioned measure different things—Beaufort for wind strength, Celsius for temperature—so they don’t quantify cloudiness. Therefore, the Oktas scale is the method used to measure cloud cover.

Cloud cover is estimated by judging how much of the sky is shaded by clouds, using the Oktas scale. This scale measures cloudiness in eighths of the sky, from 0 (a completely clear sky) to 8 (a completely overcast sky). In practice, observers note cloud cover in octas or with sky-cover codes like FEW (1–2 octas), SCT (3–4 octas), BKN (5–7 octas), and OVC (8 octas). The other scales mentioned measure different things—Beaufort for wind strength, Celsius for temperature—so they don’t quantify cloudiness. Therefore, the Oktas scale is the method used to measure cloud cover.