Complex sentence: In East Asia, the influence of the strong Siberian anticyclone brings sharper winter temperatures, pushing the southern boundary of this regime to between Yangtze and Yellow River valleys in China but its range is further north over the Pacific coastal regions of the Japanese archipelago.
Split into simpler sentences: In East Asia, the influence of the strong Siberian anticyclone brings colder winter temperatures southward, pushing the southern boundary of this regime to between the Yangtze and Yellow River valleys in China. Its range is further north over the Pacific coastal regions of the Japanese archipelago.