PLANET EARTH Deserts
These jagged（参差不齐的） pyramids a hundred meters tall were once part of a continuous rocky plateau. The blasting sand（喷射的沙子） will eventually eliminate them altogether. The relentless（relent本身有温和的意思，relentless表示残酷的，无情的，这里更多的偏向于表示坚持不断的） power of the wind ensures that the face of a desert is continually changing. But there is one constant presence - the desert sun. The sun's heat and power to evaporate water has had a profound effect（深远影响） on the bodies and habits of everything that lives here.
This sun potentially is a killer. And the red kangaroos must acknowledge that. Right now, while the sun is low, there's no immediate cause for concern. But this situation won't last long. Australia is the world's most arid（干旱的） continent with blistering（酷热的） daytime temperatures. Every hour the temperature rises by five degrees centigrade（通常可以在degree后面加celsius表示摄氏度，而书面一点的会用centigrade）. Soon the heat will reach a critical point.
