DTM

The Drag Temperature Model (DTM) is a semi-empirical model describing the temperature, density, and composition of the Earth's thermosphere in the altitude range [120 - 1,500] km. DTM2013 was developed in the framework of the Advanced Thermosphere Modelling and Orbit Prediction project (ATMOP). The DTM2013 model is fitted to the high-resolution and high-precision accelerometer-inferred densities from the CHAMP and GRACE missions, but also to 2.5 years of GOCE data at 270 km. The low-resolution densities derived from orbit perturbation analysis as well as spectrometer data from Atmosphere Explorer and Dynamics Explorer have also been used, i.e., the same density data sets that were used in the construction of DTM2009 and DTM2012. This model is constructed using the 30 cm radio flux as solar proxy, and the 3-hour am index as geomagnetic proxy.

The DTM uses solar radio flux, either F30 or F10.7 (daily and 81-day average values) and geomagnetic Kp index. The DTM at CCMC is run with F30 scaled to F10.7 and Kp.

The model predicts total and partial densities (atomic hydrogen, helium, atomic oxygen, molecular nitrogen, and molecular oxygen in g/cm^3), as well as temperature and exospheric temperature, as a function of the user-provided values of date, location, solar flux and geomagnetic activity.