This video, we're going to talk about how water affects climate. So it turns out that Earth's global air circulation, which includes the prevailing winds that we talked about in our previous lesson videos, and ocean currents known as gyres are actually really closely interconnected with each other. And so these gyres can be defined as a massive system of circulating ocean currents, and they're so massive that they actually span entire oceans. And all of these gyres are going to be transferring heat from the equator towards the poles, which is going to have a major impact on climate globally because this process will help to distribute much of the heat and energy that's beamed onto the equator and spread that heat and energy out towards the rest of the globe, balancing the temperatures of the earth to ensure that temperatures at the equator don't get too hot and that temperatures in other parts of the globe don't get too cold. Now the reason that global air circulation and ocean currents like gyres are so closely interconnected is because the global air circulation will actually physically impact the ocean surface currents.
And this is why the directions of the prevailing winds match the direction of these ocean gyres. So recall from previous lesson videos that in the northern hemisphere, the prevailing winds promote a clockwise flow, and so all of the gyres in the northern hemisphere will have a clockwise flow to them. And in the southern hemisphere, the prevailing winds somewhat promote a counterclockwise flow, and therefore, all of the gyres in the southern hemisphere have a counterclockwise flow. So now we have what we need to complete the North Pacific and South Pacific gyres interactively. So hotter water from the equator will be transferred towards the poles and cooler water from the poles will be returned back towards the equator.
And in the South Pacific Gyre, again, hotter water from the equator will be moved towards the poles and cooler water from the poles will be returned back towards the equator to complete the circular system. Now we're going to shift gears a little bit and talk about how large bodies of water tend to stabilize the climates of nearby land. And the reason that this is possible is because water has a high specific heat, which allows it to resist temperature changes. And so while the land is heating and cooling very quickly, the water that's nearby is going to heat and cool very slowly, allowing it the opportunity to stabilize the climate of nearby land. So let's take a look at these two images on the right-hand side that kind of make this a little bit more clear.
So, in the top half, we're looking at the day, and during the day the land is going to heat up pretty quickly and the air above the land will also heat up and that hot air will rise. And the water, because it has a high specific heat, will not heat up as quickly as the land will, so it's going to remain somewhat cooler, and the air above the water will be cooler as well, so it can come in to replace that hotter air to somewhat cool down the land, during the day, and that's going to help stabilize the temperature. Now at night, we'll see something similar, but what you'll notice is the land will get cooler and the water will be warmer, and so warmer air above the water can come in to kind of heat up the land at night, stabilizing the land. So this is why you may have realized from your own personal experiences that coastal regions tend to have more stable temperatures, whereas more inland regions tend to have more extreme variations in temperature. Now last but not least, we're going to talk about how water actually absorbs and sequesters or removes carbon dioxide or CO2, which is a greenhouse gas that traps heat in Earth's atmosphere.
And so by absorbing and removing CO2, it somewhat helps to cool down the earth because there's less CO2 available to trap heat in the earth's atmosphere. However, when the water does absorb CO2, it reacts to form carbonic acid, which can change the pH of the water, and that can disrupt aquatic life. And so we can't really rely on the oceans to absorb and sequester all of the CO2 that humans are emitting. Now this year concludes our lesson on how water affects climate, and I'll see you in our next video.