The current models of the atmospheric region known as the lower thermosphere (80 to 130 km in altitude) are inadequate in many respects, and the observational data to test and normalize them is quite sparse. Current efforts are under way to interpret observations made of the region during the last decade, and to obtain new data as part of the CEDAR campaign "The Lower Thermosphere Coupling Study" (LTCS). The high altitude energy inputs of the solar wind and solar ultraviolet propagate downward through the region, and the lower altitude tidal and gravity wave energy inputs propagate upward through it, both depositing some of their energy on the way. To understand the coupling between the upper and lower atmosphere we must understand the structure and dynamics of the lower thermosphere and how it affects the energy propagating through it. This award is to support a modelling project that will take an existing model that covers the atmosphere from the surface to 85 km, and extend it up to 130 km. The transfer of energy by radiation will be treated more accurately than has been possible previously, and the project should lead to a better understanding of the interactions between chemistry, radiation, and dynamics in the atmosphere, with possible consequences for better understanding of changes in weather and climate.