Just imagine going to the beach, taking in the earthy and salty scents of the sea when the wind blows in your face and as you tingled your nose as you breathed in a breath of fresh air with your eyes fixated on its smooth and crushing bright blue waves. The sun worked its way up to the sky, dispersing its power to everything at its sight. It’s daytime and the place is breathtaking. A while later, you feel your bare feet get hot from touching the golden sand that covers the floor. You tried splashing your body with water and observed it to be warm but not quite like the sand’s blazing sensation that compels you to say—my, my, ah ouch! A resonating ‘why’ echoes on your mind. Why? Why, on the same day, are the temperatures of water and sand so different? This can be explained using the notion of specific heat capacity which is “the quantity of heat required to raise the temperature of a substance by one degree Celsius” (KentChemistry, n.
d.). In simpler terms, it means how much energy is needed to raise the temperature of a substance. So if we compare the two substances, the temperature of sand rises very fast as compared to water.
It is because sand has lower specific heat of 0.67 J. For this reason, the sand requires less heat energy in order to have that rise in temperature.
It just makes sense why its temperature changes more quickly. On the other hand, water has a high—very high specific heat, higher than sand and any other materials. In essence, what this means is that water absorbs a lot of the sun’s heat before it begins to warm up or before its temperature changes. In fact, Tiffany (2016) said that 1 gram of water must absorb 4.186 Joules of heat energy before it’s temperature will rise by 1 degree Celcius (°C). Specific heat capacity can also be explained as resistance to change in temperature, as subtly noted above. The higher specific heat capacity of a substance entails longer time and therefore, harder to change the temperature of its certain mass (by 1 degree). In this case, it is harder to change the temperature of water than it is to change the temperature of sand.
One of the most obvious effects of the high heat capacity of water and lower heat capacity of sand in the land is the daily occurrence of land and sea breezes. Land and sea breezes help regulate Earth’s climate; since land is warmer during the day, it heats the air in the atmosphere above it, which causes the air to expand, becoming less dense and thus, creating a low pressure. On the other hand, because water warms up slower, the air above it takes longer to increase in temperature and so, a higher pressure is maintained. As a result, a sea breeze forms when air moves from an area of high pressure to an area of low pressure in an attempt to equalize pressure.
At night, as the land becomes cooler, so does the air above it. Therefore, the air over the sea becomes warmer than the air over the land. Again, in an attempt to equalize pressure, the warm air rises and the cooler air moves to replace the rising warm air creating a land breeze. These are some examples of how the properties of land and water help regulate Earth’s climate.
To that end, water does take time to get heated and also takes equivalent time to cool down which shows that it has high, in fact, very high specific heat capacity than sand which gets heated up and gets cooled quickly.