Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs.
考虑到资源分配的不平等，高原印加人需要获得海拔较低、较温暖的区域的产品，以扩大食物的种类和数量。
2
This is because as the ice sheet melts, its surface will be at ever lower altitudes, where the air will be progressively warmer, even if global warming ceases.
这是因为，随着冰盖融化，其表面高度将越来越低，即使全球变暖停止，那里的空气也会逐渐变暖。
3
They lived in Yosemite Valley near the river. During the extremely cold winters, these people would move to lower, warmer areas.