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.
There are three main driving forces for the movement of the Earth's tectonic plates. They are mantle convection, gravity, and the Earth's rotation. Mantle convection is the most widely studied method of tectonic plate movement and it is very similar to the theory developed by Holmes in 1929.n 1961 and 1962, scientists proposed the process of sea floor spreading caused by mantle convection to explain the movement of the Earth's continents and plate tectonics.