The above disagreement about wind ripples wavelength results from lack of physical observations about initial morphs which are referred as initial waves or mottlers in physical observations (Seppala and Linde, 1978; Andreotti et al., 2006) and numeric tests (e.g. Andersen, 1987, 1990; Wener and Gillespie, 1993; Qian and Miao, 2008; Zheng and Bo, 2009).