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:

-CESM main page
-CESM quick start guide
-WACCM-X Compsets
-CESM/WACCM-X description

    • Whole Atmosphere Working Group:


    • WACCM at ACOM:


    • Sign up for WACCM-X Mailing list


News and Updates:

    • Extended runs of WACCM-X v. 2.1 with specified dynamics forcing available for analysis


    • Climate change model output archived (Solomon et al., 2018; 2019)


    • WACCM-X v. 2.1, is released as part of the Community Earth System Model, v. 2.1, January 2019.

-Release Notes for WACCM-X v.2.1

    • WACCM-X v. 2.0, with fully-interactive ionosphere, is released as part of the Community Earth System Model, v. 2.0, June 2018.

-Release Notes for WACCM-X v.2.0

Recent Workshops and Symposia:

    • System Science Workshop 2018
-Toward a Whole Geospace Model

    • CEDAR Workshop 2018
-Hanli Liu's CEDAR Prize Lecture

    • Whole Atmosphere Modeling Workshop, June 13-15, 2018
  • Whole Atmosphere Data Assimilation in WACCMX+DART
  • CESM: A platform for atmospheric prediction from the surface to geospace
  • Whole Atmosphere Community Climate Model with Thermosphere/Ionosphere Extension (WACCM-X)
      • Whole Atmosphere Working Group Meeting, Feb. 12–14, 2018

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

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

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

    WACCM-X Highlights:

    Lagrangian coherent structures (LCSs) are indicating regions of material transport
    May 5, 2022

    Lagrangian coherent structures (LCSs), indicating regions of material transport, are derived from models of the lower thermosphere for five space shuttle water vapor plume events.

    Colorful multiple grids of simulation experiments
    March 1, 2022

    The upward plasma drift and equatorial ionization anomaly (EIA) in the Earth's ionosphere are strongly influenced by the zonal electric field, which is generated by the wind dynamo.

    migrating semidiurnal tide amplitude in zonal wind
    August 13, 2021

    Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (SD-WACCMX) simulations are used to investigate the solar migrating semidiurnal tide (SW2) around September equinox at middle to high latitudes in the Northern Hemisphere.

    Daily average WACCMX+DART NO profiles
    July 13, 2021

    The energetic particle precipitation (EPP) indirect effect (IE) refers to the downward transport of reactive odd nitrogen (NOx=NO+NO2) produced by EPP (EPP-NOx) from the polar winter mesosphere and lower thermosphere to the stratosphere where it can destroy ozone.

    Difference between zonal wind field and prior ensemble
    July 9, 2021

    The thermospheric data assimilation is limited due to the lack of continuous observation of the neutral state.