Table 1. Surface Layer Depth and Subsurface Layer Thickness Acronyms and Descriptions


Labels	Defined	Description

Surface Layer Depths
IPLD	iso-pycnal layer depth	Estimated by variable density threshold based on 0.2degreeC temperature change [Kara et al., 2000a]
ITLD	iso-thermal layer depth	Estimated by 0.2degreeC temperature threshold
IHLD	iso-haline layer depth	Estimated by variable salinity threshold based on 0.2degreeC temperature change (see section 4.1)
MLD	mixed layer depth	Minimum of IPLD, ITLD, and IHLD

Subsurface Layer Thicknesses
ITGLT	isothermal density gradient layer thickness	ITLD-IPLD
IHGLT	isohaline density gradient layer thickness	IHLD-IPLD
CLT	compensation layer thickness	IPLD-MLD
TLT	transition layer thickness	Distance between the MLD and the last half-maximum buoyancy frequency (section 3)

Dimensionless Index
CI	T versus S Control Index	(IHLD-ITLD)/(ITLD+IHLD), Positive for T and negative for S control of the MLD (section 5)