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Researchers reporting in ACS' Environmental Science & Technology Letters have detected light-absorbing "tarballs" in the Himalayan atmosphere, which could contribute to glacial melt.

Importance of Himalayan 

Himalaya-Tibetan Plateau is referred as the "third pole" because the region has the largest reserve of glacial snow and ice outside of the north and south poles. 

Tarballs are small light-absorbing, carbonaceous particles formed due to burning of biomass or fossil fuels that deposit on snow and ice. Tarballs were emitted from biomass burning in the Indo-Gangetic Plain.

How are they formed?

• They are formed from brown carbon, emitted during the burning of fossil fuels.
• The median sizes of externally mixed tarballs and internally mixed tarballs were 213 and 348 nanometre respectively.
• Primary brown carbon (BrC) co-emitted with black carbon (BC) from biomass burning is an important light-absorbing carbonaceous aerosol.
• The black carbon from the Indo-Gangetic Plain can reach the Himalaya region and influence glacial melting and climatic change.

The report

Until now, black carbon was found to be transported long distances by the wind to the Himalayan atmosphere.

• It was published in ACS’ Environmental Science & Technology Letters November 4, 2020.
• A team of researchers from the Zhejiang University analyzed the wind patterns and satellite data from the station.
• The percentage of the tarballs increased on days of higher levels of pollution and could contribute to hastening of glacial melt and global warming, the study said.
• The researchers concluded that tarballs from long-range transport can be an important factor in the climatic effect and would correspond to a substantial influence on glacial melting in the Himalaya region.
• They suggested future climate models to consider the long-range transport of tarballs to the Himalayas to arrest climate change developments.

Source: DTE