The presence of waters near the freezing point alters the balance of the relative effects of contrasts in salinity and temperature on sea water density. This is described in the equation,
where  is the thermal expansion coefficient and  is the haline contraction coefficient. In particular, the ratio  is crucial. Using the observed temperatures and salinities, in the modern ocean,  is about 10 whilst at the LGM  it is estimated to have been closer to 25. The modern thermohaline circulation is thus more controlled by density contrasts due to thermal differences, whereas during the LGM the oceans were more than twice as sensitive to differences in salinity rather than temperature. In this way, the thermohaline circulation can be considered to have been less "thermo" and more "haline".