All together, the Badlands cover more than fifteen thousand square kilometers. About ten percent is national parkland. The area is a study in extremes. Temperatures in the summer have been as high as forty-six degrees Celsius
翻译其中的The area is a study in extremes

study 这里意思是“典型”----a perfect example of sth

后面接"in sth"

因为后面提到了“气温”。所以应该是“极端气候条件”

直译：该区域是极端气候条件的典型。

意译: 该地区气候条件极端恶劣。