Retrieval of Asian Dust Amount over Land using ADEOS-II/GLI near UV Data

Abstract

We propose a retrieval method of Asian dust (Yellow sand or Kosa aerosol) columnar amount around source regions using a near ultraviolet radiometry observation from space. The method simultaneously retrieves an optical thickness and mode radius of Kosa aerosol, and then derives its columnar amount. The method was applied to ADEOS-II/GLI data in the spring of 2003 around Taklimakan desert source region, inland China. The retrieved optical thickness and mode radius were about 0.34 and 1.75 µm, respectively, at a validation site. They are comparable to the in situ observations conducted within the framework of ADEC project. The estimated columnar amount around a validation site is about 2.77 g m 2 , which seems reasonable under a relatively calm situation. The method should be further validated with a regional model simulation study, and then it is useful to monitor Asian dust around source regions from space in the future.

Role of boundary layer and cumulus convection on dust emission and transport over a midlatitude desert area

“…However, the CONTROL was not able to reproduce the observed decrease of the AOT in the lowest layer shown in Figure 17; this is probably due to more persistent dust emission at the surface in the model than in the real situation and may also be due to the slow fallout speed of the dust particle considered here. However, as indicated by Takemi et al [2005], the mean column dust content in the CONTROL was in fair agreement with the retrieved values with remote‐sensing data [ Kuji et al , 2005]. Therefore the vertical distribution and the diurnal variation of dense dust in the boundary layer simulated in our modeling setup seems to be consistent with the lidar observations.…”