Spacebased Ocean-atmosphere Water ExchangeMoisture transport integrated over depth of atmosphere and its divergence (equivalent to evaporation - precipitation) are derived for a decade (daily and monthly maps).
Sufficient coverage and resolution of moisture transport integrated over depth of the atmosphere (Θ), evaporation (E), and precipitation (P) can be best achieved from the vantage point of space. The estimation of E, P, and Θ from space observations is described in Liu and Xie (2012). The figure shows that the annual mean of ∇⋅Θ bears similar large-scale features as that of E-P despite of regional discrepancies. The image was published in the textbook "Atmospheric science, second edition: An introductory survey" by J. M. Wallace and P. V. Hobbs (2006). Details of methodology to retrieve Θ can be found in Xie et al. (2008). Application of Θ to study the precipitation jump paradox in the West African monsoon (WAM) region is presented in Liu et al. (2012).