Six of the trees were grown at ambient air temperatures and six at temperatures three degrees Celsius higher.

其中6棵树种植在周围温度与环境温度一致的地区，另外6棵树种植在周围温度比环境温度高3摄氏度的地区。

" Speed reductions are based on the rail temperature, not the ambient (air) temperature, " Amtrak's statement read. " That data ensures we're only issuing heat restrictions when necessary."

“降速是基于铁路温度，而不是环境（空气）温度，” 美国铁路公司的声明写道。“这些数据确保我们只在必要时发布高温限制。”