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为什么沙漠夜晚会变得异常寒冷？

Deserts cool rapidly after sunset because they lack moisture, clouds, and vegetation — all of which trap heat near Earth’s surface.
Dry air holds very little water vapor, and since water vapor is a strong greenhouse gas, it cannot re-radiate much heat back downward.
Sand and rock absorb intense solar energy during the day but also lose it quickly at night through infrared radiation.
Without cloud cover to reflect outgoing heat, that energy escapes directly into space, causing sharp temperature drops.
In some deserts, temperatures may fall more than 30°C between afternoon and pre-dawn hours.
This large diurnal range makes desert survival challenging for plants and animals, driving adaptations like nocturnal activity.
Thermometers placed just above hot sand at noon may read over 70°C, yet dip below freezing before sunrise.
Satellites clearly detect this effect: desert surfaces emit far more longwave radiation at night than humid regions do.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

In some deserts, temperatures may fall more than 30°C between afternoon and pre-dawn hours. 某些沙漠午后至黎明前的温差可超过30°C。
Deserts cool rapidly after sunset because they lack moisture, clouds, and vegetation — all of which trap heat near Earth’s surface. 沙漠日落后迅速降温，因为缺乏水分、云层和植被——而这些都能将热量滞留在地表附近。
Dry air holds very little water vapor, and since water vapor is a strong greenhouse gas, it cannot re-radiate much heat back downward. 干燥空气含水汽极少，而水汽是一种强效温室气体，因此无法向下辐射大量热量。

这篇中文题目最接近哪一句？为什么沙漠夜晚会变得异常寒冷？一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？沙漠日落后迅速降温，因为缺乏水分、云层和植被——而这些都能将热量滞留在地表附近。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） Why Deserts Get So Cold at Night How to cook noodles A maths worksheet

In some deserts, temperatures may fall more than 30°C between afternoon and pre-dawn hours.

In some deserts, temperatures may fall more than 30°C between afternoon and pre-dawn hours.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：In some deserts, temperatures may fall more than 30°C between afternoon and pre-dawn hours.