Briefly explain how variations in water density can cause horizontal convection currents in sea water.

Convection currents flow due to variations in the temperature and salinity in seawater, both of which influence its density. Variations in density in different regions of the ocean will cause water to flow from less dense areas to more dense areas as water heats up and becomes less saline, producing a horizontal convection current. Vertical convection currents can arise as cooler, more saline water sinks, causing warmer, less saline water to rise.

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Convection currents flow due to variations in the temperature and salinity in seawater, both of which influence its density. Variations in density in different regions of the ocean will cause water to flow from less dense areas to more dense areas as water heats up and becomes less saline, producing a horizontal convection current. Vertical convection currents can arise as cooler, more saline water sinks, causing warmer, less saline water to rise.

Explanation:

it is very hard for the climatologists to precisely predict how will the global temperatures be changing so there's lots of models, some of which differ significantly, this is due to multiple factors, and probably the most important is the human activity.

humans have been a key factor in climate change around the globe since the start of the industrial revolution, and in the past few decades the consequences are becoming more obvious. there's lots of emission of pollutants in the atmosphere as well as changing the environment on the surface itself, so it's really hard to predict how will that go in the future because there's some countries that are reducing the damage and are going towards green energy, while others are stubbornly continuing with pollution and damages to the environment.