Ground Water Extraction On Earth’s Spin: Findings
A recent study published in Geophysical Research Letters has shed light on the significant impact of Groundwater Extraction on Earth’s Rotational Axis and its contribution to global sea-level rise.
- Researchers analyzed changes in the drift of Earth’s rotational pole and water movement first, by accounting for just ice sheets and Glaciers and then by adding different groundwater redistribution scenarios.
Key Findings of the Study:
- Groundwater pumping has tilted Earth nearly 80 centimeters east between 1993 and 2010 alone.
- The water circulated across the planet determines how mass is distributed.
- Between 1993 and 2010, people pumped 2,150 gigatons of groundwater, or more than 6 millimeters of sea level increase.
- Excessive groundwater pumping has caused the Earth’s pole to drift at a rate of 4.36 centimeters per year between 1993 and 2010, making it the climate-related factor with the greatest impact on polar motion.
- Redistributing water from the mid-latitudes significantly influences polar drift; therefore, the location of redistribution determines polar drift.
- During the study period, most redistribution occurred in western North America and northwestern India — both located at mid-latitudes.
- Groundwater pumping contributed to a sea-level rise of 6.24 mm during the mentioned period.
- Pumping from mid latitude areas, such as northwest India and western North America, has the most substantial influence on Earth’s axis drift.
- The rotational pole normally changes by several metres within about a year, so changes due to groundwater pumping don’t run the risk of shifting seasons.
- But on geologic time scales, polar drift can have an impact on climate.
