Shrinking tropical glaciers linked to warmer Pacific temperatures

COLUMBUS, Ohio (WCMH) -- Tropical glaciers continue to lose ice at a faster pace than in most other parts of the world.

The size of the largest tropical glacier in the world, located in the Andes Mountains of southeastern Peru, has been monitored by Ohio State University scientists for the past 50 years.

Ohio State School of Earth Sciences Ph.D. candidate Kara Lamantia developed a code with the aid of satellite data to track how the snow-covered Quelccaya Ice Cap has been affected by temperature and snowfall patterns in the wet season caused by regional warming associated with an El Niño climate pattern.

El Niño, which occurs every 2 to 7 years, and La Niña represent alternate warm and cool climate systems in the eastern and central tropical Pacific Ocean, referred to as the El Niño-Southern Oscillation, or ENSO.

"In the years where there are El Niños, the snow-covered area is drastically smaller, like 50 percent or more smaller, than the previous year. It's a concern because there is no accumulation happening in that wet season, so there's not as much snowfall," Lamantia said. She explained that in El Niño winters, southern Peru experiences warmer and drier conditions compared to average.

NASA Landsat satellite imagery reveals that the Quelccaya Ice Cap lost about 58 percent of its snow cover (about 37 percent of the total area) in El Niño wet seasons.

"We've really been able to document not only the history that's in the ice but how the ice is responding to climate change today," said Lonnie Thompson, distinguished professor of Earth Sciences at Ohio State, and senior research scientist at the university's Byrd Polar and Climate Research Center.

Thompson has made more than 50 expeditions to ice sheets and glaciers around the world and drilled ice cores under exceptionally challenging weather conditions at high altitudes.

The severe storm season in Ohio earlier in the year was likely juiced up by a strong El Niño pattern and an unusually wavy jet stream, which is conducive to severe weather by bringing together clashing air masses, coupled with wind shear (winds changing speed/and direction with height).

In Ohio, we've seen a record number of tornadoes in 2024 (73), which often came in clusters: February 28 (9); March 14 (9); April 2 (11), April 17 (5); May 7-8 (19), June 5 (4); August 6 (5).

The strongest thunderstorms evolve where deep wind shear overlaps instability (warmth and moisture beneath a layer of cool, dry air), promoting lift and and rotating storm updrafts (supercells).

"While we can't relate explicitly individual tornadoes to climate change, we can relate the large-scale environment to patterns that might be associated with a warming climate," said Jana Houser, an associate professor of meteorology at Ohio State.

Doppler weather provides more details into the intricate combination of environmental variables that spawns tornadoes. "The high-resolution radars that we can have right now look at things very quickly and at very close ranges are showing us that tornadoes form incredibly quickly," Houser said.

"We're looking at creating forecasts that are able to predict individual storms in a general sense, and then when we're looking at a forecast model, as an operational meteorologist, we're looking at sort of the idea that, hey, we have an actual storm that's forming in the vicinity where these predicted storms were … are actually rotating."

Lamantia's research helps scientists analyze snow cover data on a weekly basis, instead of waiting several years to undertake a potentially hazardous journey to the relatively flat, windswept open expanse of the mountaintop ice cap, which sits an elevation of 18,600 feet (5,680 meters).

"We get very warm water in the tropical Pacific, and within 3 months that heat is transmitted up into the atmosphere over this ice cap and throughout the tropics," Thompson said.

Stronger El Niños in the future, fueled by rising air and seawater temperatures, add energy to the atmosphere that influences the jet stream and storm track, impacting the weather and climate worldwide.