You know, I am still not too clear about the hydrologic cycle, the transfer of water back and forth between the earth and the atmosphere.

你知道，我仍然不是很清楚水文循环，也就是水在地球和大气之间的来回转移。

youdao

Glaciers are part of Earth's hydrologic cycle and are second only to the oceans in the total amount of water contained.

冰川是地球水循环的一部分，其含水量仅次于海洋。

youdao

Only when a system possesses natural or artificial boundariesthat associate the water within it with the hydrologic cycle may theentire system properly be termed hydrogeologic.

只有当某一地质系统拥有自然的或人工的界限，将该系统内的水与水文循环起来，这整个系统方能被恰当地称为与水文地质学相关。

youdao

In parallel, the trends being observed in the different variables of the hydrologic cycle evidence the exacerbation of such conditions (Sixth Water Dialogue, 2006).

UNESCO: Climatic Change