Independent Subspace Analysis of the Sea Surface Temperature Variability: Non-Gaussian Sources and Sensitivity to Sampling and Dimensionality

Table 1

EOF description with the main SSTA modes, along with corresponding available indices from literature and references.

EOF rank	Description with the main SSTA modes	Available index	PC/Index cor.	Refs.	Notes
1	El Niño (ENSO)	MEI	0.98	[56]
2	Atlantic Multi-Decadal Oscillation (AMO)	AMO	0.80	[57]
3	Pacific Decadal Oscillation (PDO): negative phase	PDO		[58, 59]
4	Northern Pacific Gyre Oscillation (NPGO)	NPGO		[60]
	El Niño Modoki (EM): negative phase	EMI		[61]	Also known as Central Pacific or noncanonical El Niño
5	El Niño Modoki (EM): positive phase	EMI		[61]
	Subtropical Indian Ocean Dipole: negative phase	SIOD		[62, 63]	First EOF mode of the SSTA in the Indian Ocean ranging in the 15°S–45°S band
6	Atlantic Niño: negative phase	ATL3		[64, 65]
	South Atlantic Subtropical Dipole	SASD		[66]	First EOF coupled mode of the SSTA/wind in the South Atlantic
	Subtropical Indian Ocean Dipole: positive phase	SIOD		[62, 63]	First EOF mode of the SSTA in the Indian Ocean ranging in the 15°S–45°S band
	Zonally oriented dipole in South Pacific			[67, 68]	Second EOF of the South Pacific SSTA
7	Meridional sequence of dipoles crossing the North-South Pacific
	South Pacific Ocean Dipole (SPOD)	SPOD		[67, 69]	First EOF of the South Pacific SSTA
8	North Atlantic tripole (NAT)	NAT		[70]
	Tropical Atlantic SST dipole			[68]
9	South Pacific Ocean Dipole (SPOD)	SPOD		[67, 69]	First EOF of the South Pacific SSTA
10	Zonally oriented dipole in South Atlantic			[68]
	Zonally oriented dipole in South Pacific			[67, 68]	Second EOF of the South Pacific SSTA
11	Meridional Pacific wavelike pattern
	Meridional Atlantic wavelike pattern
	Subtropical Indian Ocean Dipole (positive phase)	SIOD		[62, 63]	First EOF mode of the SSTA in the Indian Ocean ranging in the 15°S–45°S band
12	Tripolar pattern in North Pacific
	North Atlantic tripole (NAT)	NAT		[70]