Tarballs; Water Crisis In Cities; Biodiversity Loss & Forests


  • According to a study published in ACS’ Environmental Science & Technology Letters, 28 per cent of particles collected from the air samples from a research station in the Himalaya-Tibetan Plateau were tarballs.
  • Tarballs are small light-absorbing, carbonaceous particles formed due to burning of biomass or fossil fuels that deposit on snow and ice.
  • The percentage of the tarballs increased on days of higher levels of pollution.
  • It could contribute to hastening of glacial melt and global warming.
  • Tarballs are formed from brown carbon.
  • Brown Carbon is emitted during the burning of fossil fuels.
  • 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.

Water Crisis In Cities

  • A recent study by the World Wide Fund for Nature (WWF) says that a hundred cities worldwide face the risk of ‘severe water scarcity’ by 2050.
  • 30 of these 100 cities belong to India.
  • Dramatic increase in population will be the major factor for a grave water risk in these cities.
  • According to a statement issued by WWF-India, these cities will see a dramatic increase in their population percentage to 51 per cent by 2050, from 17 per cent in 2020.
  • More than half of the identified cities are from China and India.   
  • The study has recommended that cities should invest more in nature-based solutions and enhance the health of river basins, watersheds and wetlands to build resilience to water risks.
  • To manage these initiatives, a public funding pool needed to be created in collaboration with the private sector to invest, reduce risk and generate returns and fuel sustainable economic growth.
  • Cities also needed to support greater global efforts to mitigate greenhouse gas emissions to avoid reaching these scenarios.
  • WWF also launched an online tool called the WWF Water Risk Filter to help cities imagine future water risks.

Biodiversity Loss & Forests

  • Norwegian University of Science and Technology recently released a global study on the loss of biodiversity across the world.
  • According to this study, top biodiversity hotspots of the world lost 148 million hectares (mha) of land to agriculture and urbanisation between 1992 and 2015.
  • Forests alone accounted for nearly 40 per cent loss of biodiversity.
  • The three largest losses in forest area occurred in the biodiversity hotspots of Sundaland (Indonesia), Indo-Burma (mainland southeast Asia) and Mesoamerica.
  • The three hotspots accounted for forest losses of 11 mha, 6 mha, and 5 mha respectively.
  • A ‘biodiversity hotspot’ was defined as an area that contained “exceptional concentrations of endemic species that were undergoing exceptional loss of habitat”.
  • Sundaland, Indo-Burma and Mesoamerica are all in the tropics. They lost forests due to three major reasons.