Fig. 8
From: A role for orbital eccentricity in Earth’s seasonal climate
Zonal wavenumber 1 response to the distance-effect annual cycle. The difference between the distance-only run and zero annual forcing run (former minus latter) of Chiang et al. (2022) for a 200 mb velocity potential averaged over March–June (following aphelion), and b September–December (following perihelion). The velocity potential change shows a predominantly zonal wavenumber 1 pattern with the nodal point over the Maritime continent, reversing in sign between March–June and September–December. c, d: same as a, b, respectively, but for surface pressure. The surface pressure change exhibits a see-saw in atmospheric mass between Africa/Indian ocean and the Pacific, again with the nodal point at the Maritime continent. Figure adapted from Chiang et al. (2022), Extended Data Fig. 8