Air temperature, ZAC_U

Air temperature at a height above surface around 2.6 m but varying when winter accumulation. See height variations in the boom height variable.空气温度的测量高度距地表约2.6米，冬季积雪堆积时该高度会发生变化。具体高度变化情况请参见吊杆高度（boom height）变量。