Why is the valley of the Amur River warmer than the valleys of the other rivers shown on the map?

The valley of the Amur River is warmer than the valleys of other rivers due to its geographic location and climate. It is situated further south and benefits from a milder continental climate, which results in warmer temperatures. Additionally, the valley's topography and surrounding landforms can help trap heat, contributing to a more temperate environment compared to other river valleys shown on the map.