Question

In the desert regions of the southwestern united states, daily high and low temperatures will frequently fluctuate by or more. which statement below best explains the large variation in temperature? responses there are no bordering oceans or large bodies of water to provide a stabilizing humidity to the air. there are no bordering oceans or large bodies of water to provide a stabilizing humidity to the air. the nearby rocky mountain range provides a rain shadow effect in the evenings to the west. the nearby rocky mountain range provides a rain shadow effect in the evenings to the west. the flat, light-colored sand formations typical in deserts reflect light from the sun during the day, but not at night. the flat, light-colored sand formations typical in deserts reflect light from the sun during the day, but not at night. desert plants have long tap roots that pull water from deep in the soil, cooling the desert at night. In the desert regions of the southwestern United States, daily high and low temperatures frequently fluctuate by a large margin. What is the primary reason for this large temperature variation? a) The nearby rocky mountain range provides a rain shadow effect in the evenings to the west. b) The flat, light-colored sand formations typical in deserts reflect light from the sun during the day, but not at night. c) There are no bordering oceans or large bodies of water to provide a stabilizing humidity to the air. d) Desert plants have long tap roots that pull water from deep in the soil, cooling the desert at night.

Answer 1

The primary reason for the large temperature variation in the desert regions of the southwestern United States is the lack of humidity in the air, due to the absence of nearby large bodies of water that would otherwise provide a stabilizing influence on temperatures. The correct option is (c).

Step-by-step explanation:

In the desert regions of the southwestern United States, the large fluctuation in daily high and low temperatures is primarily due to the lack of atmospheric humidity. The correct answer to the question of why there is a large temperature variation is (c) There are no bordering oceans or large bodies of water to provide a stabilizing humidity to the air.

Oceans and large bodies of water provide a moderating effect on the temperature by adding moisture to the air, which helps retain heat during the night and reduces heating during the day. Without this humidity, deserts can have extremely high temperatures in the daylight, exceeding 60°C (140°F), while nighttime temperatures can approach freezing, often nearing 0°C (32°F). This happens because dry air allows for rapid cooling at night and quick heating during the day.

The absence of sufficient humidity in desert climates leads to substantial radiative cooling of the land surface after sunset, and given that there is little monthly variation in precipitation and often exceedingly low annual rainfall, there is little water available to buffer these heat exchanges.