  The Atmospheric Chemistry and Energetics (ACE) 1D model is a first principles
based model that generates a globally averaged thermosphere and ionosphere in
terms of constituent major, minor, and charged species, as well as associated
temperatures. The model solves the 1D continuity and energy equations
representing relevant physical processes, and is supported by a chemistry
scheme that reflects our current understanding of chemical processes in the
region. The model is a first in its detailed treatment of Nitric oxide (NO)
chemistry, including the N$_2$(A) + O reaction as a source, and accounting for
chemiluminescence effects resulting from the vibrationally excited NO produced
by N($^2$D, $^4$S) + O$_2$. The model utilizes globally averaged solar fluxes
between 0.05-175 nm as the primary form of energy input, parameterized using
the F10.7 index to reflect variations over the course of a solar cycle. The
model also includes joule heating effects, magnetospheric fluxes, and a
parameterized treatment of photoelectron effects as secondary heating sources.
The energy inputs are balanced by radiative losses from the neutral
thermosphere in the form of infrared emissions from CO$_2$, NO and O($^3$P).
Atmospheric profiles are generated for a solar cycle, and are compared with
empirical model results as well as observational data. On average, calculated
exospheric temperatures are within 10% of MSIS values, while peak electron
densities are within a factor of 2 of IRI values. The model is shown to
reproduce the NO peak at 106 km, and densities within 25% of globally averaged
satellite measurements.
