Melting glaciers threaten global water security

[Judi Lynn]

Melting glaciers threaten global water security
02-25-2025

ByJordan Joseph
Earth.com staff writer

Glaciers hold vast amounts of fresh water that are essential for people and the environment. Recent findings show that these ice bodies have been shrinking faster than many expected, sparking serious concerns among experts. Such large-scale ice loss has been tied to rising temperatures in various regions.

An international research team recently tracked changes in nearly 275,000 glaciers since the early 2000s. The analysis indicates that these glaciers have lost around five percent of their total volume, a development that few anticipated at this scale.

“We compiled 233 estimates of regional glacier mass changes from about 450 data contributors organised in 35 research teams,” explained Michael Zemp, who led the study. The goal of this extensive analysis was to create a more reliable view of glacial decline worldwide.

Measuring the worldwide impact

Researchers have linked melting glaciers to a rise in sea level of 18 millimeters. The infusion of meltwater is ranked as the second biggest contributor to rising seas, following the thermal expansion of warming ocean waters.


More:
https://www.earth.com/news/melting-glaciers-threaten-global-water-security/

[GreenWave]

1. It seems like this study excludes major ice melt players such as Antartica.

https://sealevel.nasa.gov/faq/13/how-long-have-sea-levels-been-rising-how-does-recent-sea-level-rise-compare-to-that-over-the-previous/


How long have sea levels been rising? How does recent sea-level rise compare to that over the previous centuries?

Between about 21,000 years and about 11,700 years ago, Earth warmed about 4 degrees C (7.2 degrees F), and the oceans rose (with a slight lag after the onset of warming) about 85 meters, or about 280 feet. However, sea levels continued to rise another 45 meters (about 150 feet) after the warming ended, to a total of 130 meters (from its initial level, before warming began), or about 430 feet, reaching its modern level about 3,000 years ago.

This means that, even after temperatures reached their maximum and leveled off, the ice sheets continued to melt for another 8,000 years until they reached an equilibrium with temperatures.

Stated another way, the ice sheets’ response to warming continued for 8,000 years after warming had already ended, with the meltwater contribution to global sea levels totaling 45 additional meters of sea-level rise.

From about 3,000 years ago to about 100 years ago, sea levels naturally rose and declined slightly, with little change in the overall trend. Over the past 100 years, global temperatures have risen about 1 degree C (1.8 degrees F), with sea level response to that warming totaling about 160 to 210 mm (with about half of that amount occurring since 1993), or about 6 to 8 inches. And the current rate of sea-level rise is unprecedented over the past several millennia.