isotherm

That's the isotherm here.

等温线的方程了。

A thinner isotherm allows faster turnover of warmer waters from below, which speeds ice-melt.

更薄的等温线意味着下层温暖的海水能更快地交换上来，这将加速冰层溶化。

A thinner isotherm allows faster turnover of warmer waters from below, which speeds ice-melt. The process is self-perpetuating: as ice melts, the ocean absorbs more heat and melts more ice, and so on.

较薄的等温线使下面温暖的海水快速流转，从而加快冰融化。