Hunga Tonga-Hunga Ha'apai (HTHH) SPARC Report outline:

The HTHH community assessment spans multiple research topics but is focused on the following three science themes:

A. Plume evolution, dispersion and large-scale transport

B. Impacts on stratospheric aerosols and water, ozone and stratospheric chemistry, and transport and dynamics of the atmosphere

C. Radiative forcings from the eruption and surface climate impacts.

The chapters of the report are listed below, with a PDF giving the full structure of the report, with proposed sub-sections for each chapter, and associated science questions.

1. Intro to the eruption

2. Plume eruption and early dispersion phase (0-7 days)

3. Evolution of the volcanic cloud & its meridional dispersion (shallow BDC branch)

4. HTHH effects on stratospheric temperatures, dynamics, and transport

5. HTHH effects on ozone, OH, and stratospheric chemistry

6. Upper stratosphere to thermosphere and effects & H2O transport in deep BDC branch

7. Radiative and surface/tropospheric climate impacts of the eruption

8. Summary

9. Appendix with participating model descriptions and discussion on model limitations