So then you have natural gas' local pollution problems which are substantial.

因此，天然气在当地的污染问题非常严重。

We see drivers who are parked with their engines idling as an unnecessary source of local pollution.

我们看到那些停在车里而发动机空转的司机是不必要的当地污染源。

Despite the reduced local pollution, a toxic mix of desert dust and factory smog often hits Seoul when the winds blow in from China.

尽管首尔减少了当地的污染，但当风从中国吹来时，总会有沙漠灰尘和工厂烟雾的有毒混合物袭击首尔。

We have to do a big systems design but the benefits are huge: reliability, lower cost and getting rid of both global and local pollution.

我们必须进行宏大的系统设计，但好处是巨大的：能源可靠性，更低的成本，以及消除全球和本地的污染。