SNIPPETS - Everest glaciers could nearly disappear?

Everest glaciers could nearly disappear?

By the end of this century, the landscape around Mount Everest may drastically change. As the planet continues to warm, the Everest region of Nepal could lose most of its glaciers, according to a study published in the journal The Cryosphere.

“We did not expect to see glaciers reduced at such a large scale,” said Joseph Shea, a glacier hydrologist at the International Center for Integrated Mountain Development in Nepal and lead author of the new report. “The numbers are quite frightening.”

Joseph and his colleagues found that moderate reductions in greenhouse gas emissions could result in a 70 per cent loss of glaciers around Mount Everest, while a business-as-usual scenario in which emissions remain at the same levels could result in a 99 per cent loss.

Computational model
To arrive at these findings, Joseph and his colleagues used a computer model for glacier melt, accumulation and redistribution. They customised the model with data on temperature and precipitation, measurements from the field and remote-sensing observations collected over 50 years from the Dudh Koshi basin, which includes Mount Everest and several of the world’s other highest peaks.

The model took into account how much mass glaciers gain from snowfall, as well as the way that mass is redistributed by continual downward movement. The researchers applied the model to eight future climate scenarios, from moderate emissions reductions to none at all. The results do not bode well for the glaciers around Everest. Even if emissions are reduced by mid-century and rain in the region increases, the model predicts that the majority of the glaciers will probably disappear by 2100. What this would mean for the region is unclear. The mountains are culturally and economically important for the Nepalese, but clearing them of glaciers could make them safer for mountaineers.

While the model’s simulations corroborate field observations, Joseph said that computer models could be plagued by uncertainties and their predictions were never exact. “This is a first step, not a final answer on what will happen,” Joseph said. “But it does show that even a modest step to curb emissions now might help reduce the amount of glacier loss we’ll likely see in the future.
Rachel Nuwer

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Making LED bulbs less attractive to insects
Making LED light bulbs give off less blue light might help protect people from insect-borne diseases, according to a scientist who specialises in the environmental effects of artificial light. The scientist, Travis Longcore, a professor of spatial sciences at the University of Southern California, is working with Royal Philips, a Dutch electronics company, to develop bulbs less attractive to insects.

He took experimental Philips LED bulbs whose mix of red, blue, green and white could be “tuned” and tested them against off-the-shelf LEDs and compact fluorescent bulbs - all suspended at night over traps of soapy water in the Santa Monica Mountains. Travis’s study, published in Philosophical Transactions of the Royal Society B in March, showed that the fluorescents attracted by far the most bugs, and the tunable LEDs could be adjusted to attract about 20 per cent fewer than standard LEDs did.

Mosquitoes, sandflies and the kissing bugs that transmit malaria, leishmaniasis, Chagas and other diseases are attracted to the blue wavelengths of the oldest and cheapest LED bulbs, which were created by putting a phosphor coating on a blue diode, Longcore said. (Fluorescents also emit violet and ultraviolet, which are even more attractive, he added.)

Because many humans find bluish LED light “cold” and unflattering, the electronics industry is developing “warmer” bulbs more like incandescents. The ideal, Travis said, would be “an energy-efficient bulb that has a comfortable colour temperature and minimises insect attraction, solving all of these problems together.”

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