(AP) -- Villagers from deeply Roman Catholic south Switzerland have for centuries offered a sacred vow to God to protect them from the advancing ice mass of the Great Aletsch glacier.
Global warming is making them want to reverse their prayers, and the Alpine faithful are seeking the permission of the pope.
Since the vow was established in 1678, the deal was simple: the citizens of the isolated mountain hamlets of Fiesch and Fieschertal would pledge to lead virtuous lives. In exchange, God would spare their homes and livelihoods from being swallowed by Europe's largest glacier as it expanded toward the valley with heavy winter snows.
Times have changed, and the once-fearsome Aletsch is melting amid temperatures that are 0.7 degrees Celsius (1.3 Fahrenheit) warmer than in the 19th century. The pastor at the Ernerwald Chapel has warned his flock that a new danger threatens.
"We all know - and the Holy Father reminded us in his Easter message - that an unprecedented change in the climate is taking place," Rev. Pascal Venetz said in his sermon to 100 people at the chapel, where until modern times pious women were prohibited from wearing colored underwear for fear of provoking the glacier.
"Glacier is ice, ice is water and water is life," Venetz said to the villagers from the Valais region, which has sent its sons to protect the Vatican as Swiss Guards since the 16th century. "Without the glacier the springs run dry and the brooks evaporate. Men and women face great danger. Alps and pastures vanish and towns die out."
The Aletsch was once seen as a threat because it could encroach on inhabited areas. These days, the glacier is more of a threat because of its melting ice, which risks worsening floods in the valley and, eventually, a loss of water supply. Experts say the glacier will continue to shrink - even if temperatures stay at current levels - because the warming of the last few decades has yet to take full effect.
In a telephone interview with The Associated Press, Venetz said many townsfolk have begun questioning the ancient vow that has been commemorated every year since 1862 in a procession to the chapel on July 31, St. Ignatius' feast day.
The idea to alter the vow came from Fiesch Mayor Herbert Volken, but the concern was not driven by worldly or secular impulses. Instead, the villages "were seeing nature change all around them," and realized the glacier might soon need saving, Venetz said.
Conservation body Pro Natura says the glacier base is receding up the mountain by about 100 feet (30 meters) a year. University of Zurich geographer Hanspeter Holzhauser estimates the river of ice has retreated 2.1 miles (3.4 kilometers) since peaking in 1860 at a length of 14 miles (23 kilometers). Nearly half of the shrinkage has happened since 1950.
Venetz said there were "countless, horrible natural catastrophes" in his parish from the 17th to the 19th centuries as the glacier expanded. "These led to the big volumes of water with floods that brought great damage and calamity in our villages," he said.
Villagers should continue with the vow, but the request for divine assistance should be adjusted to conform with the changing reality of nature, the pastor said.
"Praying should of course continue, because our villages should be spared from natural catastrophes," Venetz said in his sermon. "We should at the same time pray that our glacier does not melt any further, but instead grows, and that the most important thing in life - water - remains well preserved."
He said he would ask the local bishop to seek Pope Benedict XVI's permission to change the vow, and a statement from the cantonal (state) government of Valais said a papal audience was planned for September or October.
"At our next procession, we might just be able to pray against climate change, global warming and the receding of the glacier," Venetz said.
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