Question

Osoyoos and Vancouver are both located in southern British Columbia at 49°N latitude. Vancouver is on the Pacific coast and receives over 1000 mm of rainfall per year. Osoyoos is in the Okanagan Valley, east of the Rockies, and receives only 300 mm of rainfall per year. Given the available information, which phenomenon most likely explains the arid conditions found in Osoyoos?

a. Osoyoos is located at the latitude of the dry belt.

b. Osoyoos is more influenced by El Nino events than Vancouver.

c. Osoyoos is experiencing a rain shadow effect.

d. Osoyoos is located at higher altitude

e. More incoming solar radiations reach the atmosphere in Osoyoos than in Vancouver

Answer 1

C.

Osoyoos is located in the rain shadows of the Rockies causing rain shadow effect on it.

As clouds strike and ascend up the western side of the Rockies the water contained in the clouds condenses resulting in rains. Soon the clouds reach the top of the Rockies and start descending in altitude which results in it reaching the lower higher temperatures. This raises the saturation point of the clouds and this portion of the Rockies receives no or very less rainfall.