Results showed that NEE presented obvious diurnal variation pattern with single-peak of diurnal maximum carbon assimilation at 11: 00-12: 00 (local time) with an average of -0.268 mg CO2·m-2·s-1, i.e., -6.08 μmol CO2·m-2·s-1.
During the daytime, NEE fitted fairly well with PAR in a rectangular hyperbola function with the apparent quantum yield (0.020 3 μmol CO2 μmol-1 PAR) and maximum ecosystem assimilation (9.741 1 μmol CO2·m-2·s-1).
Employing remote sensing, radiative transfer simulation, geographic information systems (GIS), land hydrological process, and data assimilation, the Chinese land data assimilation system (CLDAS) is established.
Some aspects of geostrophic adjustment are investigated by numerical experiment with nonlinear barotropic primitive equations in hemispheric area. The results are in good agreement with those obtained previously by both the linear and nonlinear theory. The characteristic time required for the adjustment process as well as the other quantitative data are given. The problem of four-dimensional assimilation is also discussed, indicating that it would not be of benefit, if the updating is made only in the...
In this paper, the two-level quasi-geostraphic model is used, the concept of assimilation of space and time is adopted, the idea of space instability is introduced and combined with time instability to study the effects of any disturbance introduced at an unidentified latitude to the general circulation. A general theory about the extent of existence of the planetary waves, the criteria of space and time instabilities and their physical implications, and the coupling of the high and low level planetar...
By using the primitive equations of motion in spherical coordinates, free oscillations of the atmosphere are discussed. These equations are linearized in relation to the atmospheric basic state. The easterly, as well as westerly mean zonal wind profile, and the associated geopotential profile are included in the basic state. Numerical method is applied to obtain the characteristic wave solutions. The ei-gensolutions by 2-order difference scheme are compared with those obtained by utilizing 4-order differenc...