Why in News?
- In a first-of-its-kind study, published in the journal Nature Communications, scientists have assessed the influence of human activities on extreme fire weather risk, and found that greenhouse gas emissions and air pollution have distinct regional impacts on wildfire outbreaks.
Findings of the study
- The research analysed the climate under various combinations of human influences since 1920, isolating individual effects and their impacts on extreme fire weather risk.
- While previous studies found that human activities and their products like greenhouse gas emissions, and air pollution raise the risk of extreme fire weather, scientists said the specific influence of these factors has been unclear.
- According to the latest research, heat-trapping greenhouse gas emissions are the dominant contributors to temperature increases around the globe.
- By 2005, emissions raised the risk of extreme fire weather by 20% from pre industrial levels in western and eastern North America, the Mediterranean, Southeast Asia, and the Amazon.
- The study predicted that by 2080, greenhouse gas emissions are expected to raise the risk of extreme wildfire by at least 50% in western North America, equatorial Africa, Southeast Asia and Australia, while doubling it in the Mediterranean, southern Africa, eastern North America and the Amazon.
- Biomass burning and land-use changes have more regional impacts that amplify greenhouse gas-driven warming.
- A 30% increase of extreme fire weather risk over the Amazon and western North America during the 20th century caused by biomass burning.
- Land use changes also amplified the risk of extreme fire weather in western Australia and the Amazon.
How does this affect India?
- Industrial aerosols block some of the solar radiation from reaching the ground and tend to have a cooling effect on the climate.
- In Southeast Asia, where aerosols emissions are expected to continue, the study said there may be a weakening of the annual monsoon, drier conditions and an increase in extreme fire weather risk.
- Southeast Asia relies on the monsoon, but aerosols cause so much cooling on land that it actually can suppress a monsoon.