EFFECT OF GROUNDWATER EXTRACTION ON EARTH TILT -UPSC Current Affairs

Description

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Context

In a recently published new study a change in tilt of earth was observed.
In the journal of the American Geophysical Union, Geophysical Research Letters, this study was published on June 15,2023.
During 1993 and 2010, Earth was tilted 80 cm to its east.
The cause of this tilt was extraction of ground water and transporting it to other locations.

Other Details

Global water circulation has relation with mass distribution across planet.
This mass distribution has bearing on the fluctuation/instability of geographic north and south poles of Earth.
Mass redistribution can cause change in these rotational pole by several metres in a year.
A total of 2,150 gigatons of groundwater is estimated to be extracted and redistributed during 1993 to 2010, which is equivalent to 6 mm sea level rise.
- It was mainly occurred in Western North America and northwestern India.
- This also caused the change in mass distribution especially if it is from the mid-latitudes.
It was evident that during 1995-2020 average drift speed was 17 times quicker compare to previous years, 1981-1995.

Various factors can cause instability in rotational poles

Ocean currents.
Convection current produced by magma.
Groundwater extraction and redistribution

Implication of change in Tilt of Earth due to groundwater redistribution

Polar drift can impact our planet’s climate.
Seasonal contrast may be enhanced which may lead to colder winters and warmer summers.
Risk of shifting seasons, however with current level of extraction there seems to be no risk as claimed by study.

Way Ahead

A slow rate of extraction of groundwater.
More wise and optimal use of available water.
Rainwater harvesting
A limit on groundwater extraction for commercial use.
Better irrigation techniques like drip irrigation should be used to achieve water efficiency.
Water losses should be minimized.
Using more clean energy as these have lower water footprint.
There should be a legal framework in place to punish the violators.

Tilt of Earth

There is a tilt of 23.5 degree in earth’s axis from its orbit plane around the sun.
The tilt towards the sun causes the formation of distinct seasons like summer, winter, of Earth.
It also derives the seasonal contrast in hemispheres.
It is also responsible for the phenomenon of Midnight Sun in higher latitudes, where sun is not set during many summer nights.

Must read Article:

https://www.iasgyan.in/daily-current-affairs/explained-what-is-winter-solstice-which-made-december-21-the-shortest-day-of-the-year

PRACTICE QUESTION

Discuss the implications of the change in Earth’s tilt. Also elaborate on the natural and man induced reasons which may cause the change in this tilt. (150 words)