With man-made reservoirs having 57% of the total global variability of water storage, human domination on the planet continues to defy nature. What’s astonishing is that man-made reservoirs are outnumbered by natural lakes and ponds by 24 to 1. This has been revealed in the first global survey of fluctuation in freshwater, which has been successfully conducted by the National Aeronautics and Space Administration (NASA).
Published in the journal Nature, the research employed Ice Cloud and land Elevation Satellite (ICESat-2), a satellite that was launched in 2018, to understand the impact of humans on freshwater resources. Data from about 227,386 water bodies that include lakes, ponds, and reservoirs all around the world were collected for more than 22 months. Over the course of time, scientists measured the changes in the level of these water bodies through the satellite.
Stanford University’s Remote Sensing Hydrologist Sarah Cooley – who led the study, said;
This kind of dataset will be so valuable for seeing how human management of water is changing in the future, and what areas are experiencing the greatest change, or experiencing threats to their water storage. This study provides us with a really valuable baseline of how humans are modulating the water cycle at the global scale.
Scientists found that water levels of lakes and ponds fluctuate by 22 cm (8.6”) from season to season. Surprisingly, the fluctuation of water levels in human-managed reservoirs is about to 86 cm (34”). Middle East, Southern Africa, and the western part of the United States of America have better human-managed variability in water storage.
NASA completes the first global survey of freshwater fluctuation on the planet to investigate the human impact on natural resources | Image: UNEP
Tropical basins have the highest natural inconsistency in surface water storage. Besides, the increasing human population has amplified the demand for freshwater, while climate change is altering its accessibility with the shifting hydrological cycles.
Now, with the satellite in orbit, scientists are receiving more data of smaller lakes and reservoirs than earlier expected. The findings of the study further laid the foundations of understanding the connection between anthropogenic activities and climate changes and how both affect the availability of freshwater.
With various regions nearing Day Zero amid global warming, water scarcity is a very possible scenario for every corner of the globe. Recently, NASA has been mapping various essential natural resources to measure the impact of human presence on the planet, while presenting a few solutions along the way.