Sample template image
WACCM-X simulation of the "April Fools" geomagnetic storm in 2001, showing the global electron column density in units of 10^12 cm^-2. Note the "tongue of ionization" extending out of both the north and south auroral regions into the dayside low-latitudes, and the highly distorted equatorial ionosphere.

The Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X) is a comprehensive numerical model, spanning the range of altitude from the Earth’s surface to the upper thermosphere.

The scientific goals of the model include studying solar impacts on the Earth atmosphere, couplings between atmosphere layers through chemical, physical and dynamical processes, and the implications of the coupling for the climate and for the near space environment. The development of the model is inter-divisional collaboration that unifies certain aspects of the upper atmospheric modeling of HAO, the middle atmosphere modeling of ACOM, and the tropospheric modeling of CGD, using the NCAR Community Earth System Model (CESM) as a common numerical framework.

More Information:

    • WACCM-X information and tutorials at CESM:


    • Whole Atmosphere Working Group:


    • WACCM at ACOM:


    • Sign up for WACCM-X Mailing list


News and Updates:

    • WACCM-X v. 2.0, with fully-interactive ionosphere, will be released as part of the Community Earth System Model, v. 2.0, in August 2017.

    • 15-year run of WACCM-X with specified dynamics forcing available for analysis

link to: https://www2.hao.ucar.edu/modeling/waccm-x/runs

Recent Workshops and Symposia:

    • WACCM-X Users Group tutorial session at the CEDAR Workshop, June 22, 2017

link to: http://cedarweb.vsp.ucar.edu/wiki/index.php/2017_Workshop:WACCM_X_Users_Group

    • Whole Atmosphere Variability session at the CEDAR Workshop, June 22, 2017

link to: http://cedarweb.vsp.ucar.edu/wiki/index.php/2017_Workshop:Whole_Atmosphere_Variability

    • Whole Atmosphere Working Group meeting at the CESM Workshop, June 20, 2017

link to: http://www.cesm.ucar.edu/events/workshops/ws.2017/

WACCM-X Overview:

WACCM-X Highlights:

median hmF2 comparison
June 5, 2017

In order to calculate the Earth’s whole atmosphere and ionosphere coupled system in a self-consistent way, new ionosphere and electrodynamo modules have been implemented in the thermosphere and ionosphere eXtension of WACCM-X. WACCX-X stands for the Whole Atmosphere Community Climate Model.

Teleconnection pattern derived from WACCM-X simulations image
May 31, 2017

This book chapter describes the basic physical processes in the thermosphere, or Earth's neutral upper atmosphere, which need to be captured in a physics-based model. Liu, H., 2014: WACCM-X simulation of tidal and planetary wave variability in the upper atmosphere.

Global temperature change
May 31, 2017

The NCAR Whole Atmosphere Community Climate Model–eXtended (WACCM-X) was used to study global temperature change throughout the atmosphere during the last several decades.

Monthly mean, globally integrated total gravity wave flux of energy
May 31, 2017

Most of the large events affecting the thermosphere and ionosphere part of the space environment come from the Sun, the solar wind, and Earth’s magnetosphere.