exacerbate
オーストラリアのグレートバリアリーフで珊瑚の白化が問題となっています。全体の35パーセントが死滅したという報告が出ています。
Mass bleaching kills 35% of coral in Great Barrier Reef
SYDNEY (Reuters) — Mass coral bleaching has destroyed at least 35 percent of the northern and central Great Barrier Reef, Australian scientists said on Monday, a major blow to the World Heritage Site that attracts about 5 billion Australian dollars (U.S.$3.59 billion) in tourism each year.
Australian scientists said the coral mortality figure will likely rise as some of the remaining 65 percent of coral in the northern and central reefs fails to recover from bleaching.
The report casts a shadow over the long-term prospects of the Great Barrier Reef against a backdrop of climate change and scientists said UNESCO may reconsider its decision not to put the World Heritage Site on its endangered list.
中略
Bleaching occurs when the water is too warm, forcing coral to expel living algae and causing it to calcify and turn white. Mildly bleached coral can recover if the temperature drops, otherwise it may die.
Although the impact has been exacerbated by one of the strongest El Nino weather systems in nearly 20 years, which raised sea temperatures in the western Pacific, scientists believe climate change is the underlying cause.
以下省略
http://the-japan-news.com/news/article/0002981928
今回取り上げるのはexacerbateです。『ライトハウス英和辞典』（第5版 研究社）で調べてみますと、他動詞で「（格式）（病気、問題など）を悪化させる」とありました。LDOCEには “to make a bad situation worse”とシンプルな意味が載っていました。記事の中ではhas been exacerbatedとなっていますので、約20年の間悪化し続けている様子がうかがえます。
この表現は過去にも取り上げられておりました。(aqua)
