Groundwater Extraction Tilts the Earth

The Earth’s axis, the point along which the planet rotates, has experienced a significant tilt of nearly 80 cm to the east. This tilt has been attributed to the pumping and movement of groundwater, as revealed by a recent study. Additionally, the study highlights the substantial volume of groundwater pumped and drained into the oceans, contributing to global sea-level rise.  

Understanding the Earth’s Axis Tilt 

• The Earth’s axis exhibits a wobbling motion influenced by various factors such as weather, seasonal changes, the molten core, and powerful hurricanes.  
• Previous studies had already established that the movement of water plays a role in the wobble. 
• However, it was not until the study conducted by scientists at the Seoul National University that the significance of groundwater in this phenomenon was recognized. 

Linking Groundwater Pumping and Axis Tilt 

• Using a climate model, the researchers associated the shift in the Earth’s axis with the movement of water, including melting ice caps and glaciers.  
• The model initially failed to match the observed drift of the axis until groundwater was incorporated into the equation.  
• This discovery unveils groundwater pumping as a previously unconsidered factor in the Earth’s axis tilt. 

Impact on Sea-Level Rise 

• Notably, the study revealed that approximately 2,150 billion tonnes of groundwater were pumped and drained into the oceans between 1993 and 2010.  
• This substantial volume contributed significantly to global sea-level rise, amounting to 6.24 mm during the specified period.  
• Groundwater pumping emerged as an unexpected source of sea-level rise, raising concerns among scientists and experts. 

Concerns and Regional Implications 

• The location of groundwater depletion plays a crucial role in the extent of axis drift.  
• The study found that mid-latitude areas, particularly northwest India and western North America, experienced significant groundwater redistribution and depletion.  
• In India, groundwater depletion is a particular concern in North India, including Punjab, Haryana, Delhi, western Uttar Pradesh, Rajasthan, as well as parts of Karnataka, Tamil Nadu, Telangana, and Andhra Pradesh.  
• The indiscriminate use of groundwater for irrigation purposes in these regions has resulted in critical groundwater levels and poses a threat to sustainable water resources. 

Month: Current Affairs - June, 2023

Category: Environment Current Affairs