Current Status and Forecast. n Tropical Pacific sea-surface temperatures (SSTs) have warmed from La NiÃ±a. Modoki (below-average SSTs, centered in the central tropical Pacific) to ENSO-neutral. Current SSTs range from slightly below average in the central Pacific to slightly above. average in the eastern Pacific. n The Climate Prediction Center (CPC) defines a La NiÃ±a event as having ONI values. of -0.5Â°C or colder for 5 consecutive months.
Convection currents move tectonic plates when there is heat inside the mantle that is rising and falling. The radioactive decay in the core is responsible for the convection currents.
What causes the currents under the tectonic plates is the heat in the surface s core. There are three different types of tectonic boundaries: convergent, plates move into each other; divergent, plates move apart; and transform, plates move sideways in relation to each other.