کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
570235 | 1452321 | 2012 | 17 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A simple column model to explore anticipated problems in variational assimilation of satellite observations A simple column model to explore anticipated problems in variational assimilation of satellite observations](/preview/png/570235.png)
We investigate a simplified form of variational data assimilation in a fully nonlinear framework with the aim of extracting dynamical development information from a sequence of observations over time. Information on the vertical wind profile, w (z), and profiles of temperature, T (z, t), and total water content, qt (z, t), as functions of height, z, and time, t, are converted to brightness temperatures at a single horizontal location by defining a two-dimensional (vertical and time) variational assimilation testbed. The profiles of T and qt are updated using a vertical advection scheme. A basic cloud scheme is used to obtain the fractional cloud amount and, when combined with the temperature field, this information is converted into a brightness temperature, using a simple radiative transfer scheme.It is shown that our model exhibits realistic behaviour with regard to the prediction of cloud, but the effects of nonlinearity become non-negligible in the variational data assimilation algorithm. A careful analysis of the application of the data assimilation scheme to this nonlinear problem is presented, the salient difficulties are highlighted, and suggestions for further developments are discussed.
Journal: Environmental Modelling & Software - Volumes 27–28, January–February 2012, Pages 23–39