The picture worsens with each round of El Nino, the unusually warm currents in the Pacific Ocean that drive up temperatures and invariably presage (预示) droughts and fires in the rain forest.
出自-2013年6月阅读原文
柯林斯高阶英汉双解学习词典释义
V-ERG
（使）变得更坏(或更糟);（使）恶化
If a bad situation worsens or if something worsens it, it becomes more difficult, unpleasant, or unacceptable.