An analysis of kosa conducted in Nagoya in 1979 showed that most of the sand grain sizes are distributed roughly between 1 μm to 30 μm, with its distribution peak at 4μm.
1979年に名古屋で採取された黄砂の分析では、おおむね1μm-30μmのものが多く4μmくらいの粒子が最も多かった。