Publication Date:
2020-12-21
Description:
This paper introduces the three-dimensional Hamburg Model of the Neutral and Ionized Atmosphere
(HAMMONIA), which treats atmospheric dynamics, radiation, and chemistry interactively for the height
range from the earth’s surface to the thermosphere (approximately 250 km). It is based on the latest version
of the ECHAM atmospheric general circulation model of the Max Planck Institute for Meteorology in
Hamburg, Germany, which is extended to include important radiative and dynamical processes of the upper
atmosphere and is coupled to a chemistry module containing 48 compounds. The model is applied to study
the effects of natural and anthropogenic climate forcing on the atmosphere, represented, on the one hand,
by the 11-yr solar cycle and, on the other hand, by a doubling of the present-day concentration of carbon
dioxide. The numerical experiments are analyzed with the focus on the effects on temperature and chemical
composition in the mesopause region. Results include a temperature response to the solar cycle by 2 to 10
K in the mesopause region with the largest values occurring slightly above the summer mesopause. Ozone
in the secondary maximum increases by up to 20% for solar maximum conditions. Changes in winds are in
general small. In the case of a doubling of carbon dioxide the simulation indicates a cooling of the atmosphere
everywhere above the tropopause but by the smallest values around the mesopause. It is shown that
the temperature response up to the mesopause is strongly influenced by changes in dynamics. During
Northern Hemisphere summer, dynamical processes alone would lead to an almost global warming of up
to 3 K in the uppermost mesosphere.
Description:
Published
Description:
3903-3931
Description:
reserved
Keywords:
Sensitivity
;
Chemistry
;
01. Atmosphere::01.01. Atmosphere::01.01.02. Climate
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
