Using a global-scale numerical model, we study the relative importance of primary (tropospheric) and non-tropospheric gravity waves. Global effects of these waves are largely captured by considering only those that originate in the lower atmosphere. However, the non-tropospheric sources contribute additional effects to the upper atmosphere, especially when they are assumed to be distributed over all heights. The importance of vertically localized sources decreases with the source height. A comparison of the model with ICON satellite observations demonstrates that the model can adequately reproduce the basic structure of thermospheric circulation when only tropospheric wave sources are included.