S. national air quality standards.During one dust storm, airborne aluminum concentrations exceeded 1,400 micrograms per cubic meter.
一场沙尘暴中，空气中的铝浓度会超过1400微克每立方米。
2
S. national air quality standards. During one dust storm, airborne aluminum concentrations exceeded 1,400 micrograms per cubic meter.
一场沙尘暴中，空气中的铝浓度会超过1400微克每立方米。
3
S. The colors indicate areas along the coast that are elevations of 1 meter or less (russet) or 6 meters or less (yellow) and have connectivity to the sea.