SINTEX-F2 simulations and linear models

These simulations and models underpin my research on the Southern Hemisphere circumpolar wavenumber-4 pattern. With the SINTEX-F2 coupled model, we showed that SST variability in the southwestern subtropical Pacific triggers the atmospheric variability that generates the pattern during austral summer, while tropical SST variability has a limited effect (Senapati et al., 2024, JGR-Oceans).

In the sensitivity experiments, SST in selected regions is kept at its climatology, removing its variability there, to isolate where the pattern originates.

SINTEX-F2 experiments

Experiment	SST kept at climatology in	Length
CTRL	None (control run)	300 years
noTP	Tropical Pacific (25°S–25°N)	300 years
noTIO	Tropical Indian Ocean	300 years
noTIOTP	Tropical Indian Ocean and tropical Pacific	300 years
noTALL	All tropical oceans (25°S–25°N)	300 years
noTMD	All oceans from 60°S to 60°N	300 years
noTS	Tasman Sea (150°E–168°W, 50°S–25°S)	100 years
noTIOTPMCTS	Tropical Indian Ocean, tropical Pacific, Maritime Continent and Tasman Sea	100 years
noTPMCTS	Tropical Pacific, Maritime Continent and Tasman Sea	100 years
noTIOTPMC	Tropical Indian Ocean, tropical Pacific and Maritime Continent	100 years

Region codes: TP tropical Pacific · TIO tropical Indian Ocean · MC Maritime Continent · TS Tasman Sea · TALL all tropical oceans.

Linear models

Linear barotropic model

Used to examine Rossby wave propagation and the atmospheric response to idealised forcing.

Linear response model

A semi-empirical linear step-response model (following Deb et al., 2020), used to estimate the Southern Hemisphere extratropical response to a step-like change in convection over the Rossby wave source region in the western subtropical Pacific (Senapati et al., 2022, Climate Dynamics).