Water is a natural resource and it is a subject that comes under geography and science and technology in the UPSC syllabus.
Water is one of the most basic, one of the most used, one of the most exploited and perhaps equal in importance to the other natural resources essential for the survival of life. Since water has been in the news for several reasons both good and bad such as droughts, heavy rain causing floods, cleaning of r river Ganga, interlinking of rivers issue, river water disputes and much more, thus it is essential to go through the topic in detail analyzing every aspect of it.
In this part, we will be looking into the basics of water as a resource before moving ahead.
Some Basic Facts
- Three-fourths of the Earth’s surface is covered with water. Hence known as the ‘water planet’
- Out of this, the oceans cover about two-thirds surface, thus unfit human consumption
- Only around 2.7% is available for human use out of which the maximum is covered under ice sheets and glaciers, thus inaccessible
- It comes down to just 1% of water that can be considered to be fit for human use
Hence, now we know and should understand that although water is a natural renewable resource, however still there is shortage as the amount of water which is fit for use is very limited. Apart from this, pollution, indiscriminate use is also affecting its reach to all.
We just mentioned that water is a naturally occurring renewable resource. Water is recycled through the process known as Water Cycle. It is represented pictographically below:
Through the picture above it is clear that water evaporates as water vapour, condenses to form clouds and then fall as rain/ snow(precipitation) and thus complete the water cycle.
- March 22 is celebrated as World Water Day
- Fresh water is distributed as being the highest in Ice-caps and least in rivers
Ocean Water Movement
Ocean Water movement can be divided into three namely,
Let us discuss them one by one.
What are waves?
They are movement of ocean water surface
What kind of movement?
Alternate rise and fall of water
What causes these waves?
They are caused by the action of winds blowing over the ocean surface. The height of the wave depends upon the strength of the wind
Thus on the basis of the above facts, we can define waves as the movement of ocean water on its surface as alternate rise and fall caused due to the action of the winds blowing over it.
It is important to understand here that wave is basically energy and not water that is moving. The water particles actually move in a circular fashion, while forming a wave like feature, seems as if the water is moving ahead. The highest point that this water can reach is known as ‘Crest’ and the lowest is known as ‘Trough’. Due to the friction caused by the sea floor, the wave decreases while reaching the beach.
It is good to know that the steeper waves are generally the young waves and caused by the local winds. On the contrary, the steady waves travel from a far away distance.
What are tides?
They are also movement of ocean water
What kind of movement?
It is the rhythmic rise and fall of ocean water
How often does it happen?
Twice a day
What causes the tides?
Gravitational pull exerted by the Sun and the Moon
Thus now we can define tides as the rhythmic rise and fall of ocean water twice a day caused by the gravitational pull exerted by the celestial bodies the Sun and the Moon.
Going a little deeper, there is a counter acting force known as the ‘Centrifugal force’. This acts against the gravitational pull of the moon or sun. As a result, there are two tidal bulges created. One by the gravitational pull of the moon or sun and the other by the counter centrifugal force.
When the tide is in between islands, or bays, etc., it is known as ‘Tidal Currents’.
The different types of tides based on the position of the Sun, moon and earth are mentioned below:
- Spring tides: When sun, moon and earth are in a straight line, they generate spring tide, which is a higher tide. It occurs on a full moon and a new moon day.
- Neap tides: Neap tides occur when the sun and moon are at right angles to each other.
Please note that during the periods of perigee and perihelion, the tides are the highest and during apogee and aphelion, the tides are the lowest. Also, the time period between the high tide and low tide when it is the highest and lowest is known as ‘flood’ and ‘ebb’ respectively.
What are currents?
They are like rivers or streams flowing in the ocean in specific directions
What causes the currents?
Some of the factors include Coriolis force, wind, gravity, salinity
It should be clear that the cold currents form due to the sinking of cold water at the poles moving towards the equator. The warm currents form due to the lighter water from the equator rising up and moving towards the poles.
The fishing grounds in the world are formed where the warm and cold ocean currents meet. This is because their mixing generates oxygen which enables the growth of planktons. Planktons are the primary food for fish and hence these areas become the best fishing grounds of the world.
The important ocean currents are as follows:
With this basic understanding, let us move ahead with the water related issues concerning the society today.
Let us try to understand modern day challenges:
- Human interference: The IPCC report has also pointed out that human activities are a big challenge in the modern day. Thus there is an urgent need to mend our lifestyle
- Mapping of reservoirs and aquifers is still at a very early stage. The pace needs to be quickened to be able to take corrective steps thereafter
- There is a series of droughts indicating the poor rainfall pattern which is persisting over years. Thus the climate change has a big role to play in adding to the miseries
- The policies of the government, their coherence among departments is lacking
- The policies themselves are not capable enough to address the present issues and even if they are, the implementation is poor
Thus, the issue of water in present day has to be looked into from a holistic point of view. There is a need to understand that it affects our society geographically, socially, economically and even at individual levels. Clean water is a basic necessity that is important for the holistic development of the society and its members.
The need of the hour is a cooperative participation by the government, citizens and civil society to come up with proper policy designs and implementation beginning at the root cause of the problem. Public-Private participation, panchayats, open public platforms can contribute to a large extent to purify this pure resource.
|Evaporation and condensation|
|National Waterways in India|