This post is part of a series of posts written by Priyadarshan Pandey.
Welcome back, watermen (no?)!
So, in the last couple of posts we talked about the reason for my importance, my structure on an atomic level and the properties it generates, and my role in sustaining life on earth. And we talked about my birth and cosmological significance. Today I would like to resume this conversation, but on a more local level (both temporally and spatially).
We discussed how oceans have helped sustain life on earth in the last post. I hope you still remember my thermal properties which are responsible for keeping the earth in the habitable zone. If you don’t, click here. This property helps keep the temperature of the earth moderate, and is also responsible for regional climatic conditions on earth. Today we will discuss this regional effect I have on climate and how it affects the world as you know it.
Everyone likes to spend a day on the beach, right? The sand, the cool sea breeze, the pleasant temperature, and the refreshing waves all sum up to make a perfect holiday. The coastal climate is moderate due to its close contact with the ocean which is a heat absorbing unit, slowly heating up when there’s sun out and releasing it when the adjacent lands gets cooler. The same effect, but on a larger scale, is responsible for all regional climatic conditions on Earth.
The ocean is crucial to heating the planet. While land areas and the atmosphere absorb some sunlight, the majority of the sun’s radiation is absorbed by the ocean. Particularly in the tropical waters around the equator, the ocean acts as a massive, heat-retaining solar panel. Earth’s atmosphere also plays a part in this process, helping to retain heat that would otherwise quickly radiate into space after sunset.
The ocean doesn’t just store solar radiation; it also helps to distribute heat around the globe. Outside of Earth’s equatorial areas, weather patterns are driven largely by ocean currents. Currents are movements of ocean water in a continuous flow, created largely by surface winds but also partly by temperature and salinity gradients, Earth’s rotation, and tides (the gravitational effects of the sun and moon). We will talk in detail about them in a later post. Today I will illustrate the importance of oceans in determining the regional climate through a few case studies. We will look upon the regions which oceans have turned hotter than they ought to be or cooler than they ought to be.
The continent of Europe is famed for its lush green hills, its castles and cathedrals, and for being the birthplace of the western civilization. But what if I were to tell you that by rights this piece of landmass should be a cold and desolate place, with climate too extreme for any ancient civilization to settle and thrive. Europe is located in the high latitude region of the earth. We know that the higher the latitude of a region, the lesser solar insolation it gets. Places along the same latitudes as Europe, like Canada and Moscow, have much harsher climate, while Europe enjoys a pleasant maritime climate. This is because Europe has a climate heavily affected by warm Atlantic currents that temper winters and summers on much of the continent, even at latitudes along which the climate in Asia and North America is severe. Further from the Atlantic, seasonal differences are mildly greater than close to the coast.
As you can see in the above illustration, a warm ocean current in the Atlantic Ocean from the tropical region flows along the western coast of Europe (mainly the British Isles). This current not only warms this region but also brings a lot of moisture along which makes the area wet and fertile. Without the North Atlantic Drift (which is how this warm current is known) Europe would be a region of extreme climate with frigid winters, enough for the white walkers to make an appearance. Remember! Winter is coming, unless you have a buddy like me.