Why does the effect of rising global temperatures in the ocean have such a broad effect on Earth?

As water cools, it can hold less carbon dioxide, so more CO is released into the atmosphere, where it is a greenhouse gas.
As water warms, it can hold less carbon dioxide, so more CO is released into the atmosphere, where it is a greenhouse gas.
As water warms, it can hold more carbon dioxide, so less CO is released into the atmosphere, where it is a greenhouse gas.
There is no overwhelming effect due to rising global temperatures.

Question

Why does the effect of rising global temperatures in the ocean have such a broad effect on Earth?
 	
	As water cools, it can hold less carbon dioxide, so more CO is released into the atmosphere, where it is a greenhouse gas.
	As water warms, it can hold less carbon dioxide, so more CO is released into the atmosphere, where it is a greenhouse gas.
	As water warms, it can hold more carbon dioxide, so less CO is released into the atmosphere, where it is a greenhouse gas.
	There is no overwhelming effect due to rising global temperatures.

micahm · Answer

wakipdia says 

Most of the global warming since the mid-20th century is very likely due to human activities. ... Some of the effects in temperate and polar regions will be positive and .... Over the past 30 years, temperatures have risen faster in winter than in any ..... There is unequivocal evidence that Earth's lower atmosphere, ocean,