十万个为什么·科学启蒙30篇（4）
22 / 30
正在校验访问权限...
Why Desert Temperatures Swing Wildly Between Day and Night
为什么沙漠昼夜温差大
-
Deserts have very little humidity, so air holds almost no water vapor to trap heat.
-
During the day, sunlight heats dry sand and rock surfaces rapidly without cloud cover.
-
At night, this stored heat escapes quickly back into space because there’s no insulating moisture layer.
-
The lack of vegetation and clouds means no barrier slows radiative cooling after sunset.
-
Temperatures can drop over 30°C within hours once the sun disappears below the horizon.
-
Thermal inertia of desert soil is low, so it cools much faster than ocean water or moist earth.
-
Radiation dominates heat loss in deserts, unlike convection or conduction in humid regions.
-
Scientists use satellite data to compare desert cooling rates with tropical forest patterns.
-
This extreme variation shapes how desert animals behave and when they hunt or rest.
-
Engineers designing solar farms in deserts must consider thermal stress on materials from daily swings.