India was among several countries in the world where greenhouse gases and carbon dioxide (CO2) emission from fossil fuels combustion reduced due to lockdowns imposed to contain the coronavirus pandemic, the National Aeronautics and Space Administration said after observing satellite data.
Americaâ€™s NASA, the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) collaborated for the first time to document planet-wide changes in the environment and societies during the lockdowns. The agencies collated data from their Earth-observing satellites tracking changes in air and water quality, climate change, economic activity, and agriculture.
According to NASA, the agencies formed a taskforce in April and identified the most relevant satellite data streams. â€œWhen we began to see from space how changing patterns of human activity caused by the pandemic were having a visible impact on the planet, we knew that if we combined resources, we could bring a powerful new analytical tool to bear on this fast-moving crisis,â€ said Thomas Zurbuchen, NASA associate administrator for science, in a statement.
How India fared?
Reduction in atmospheric CO2
Initial studies suggest that while the lockdown slowed the CO2 accumulation in the atmosphere, it may not reduce the overall atmospheric concentration of the element. “In New Delhi and Mumbai the story is somewhat more mixed. The CO2 enhancements are smaller or almost the same in February, reflecting the large role of natural processes, such as year-to-year differences in CO2 uptake and release by forests and crops,” said the taskforce.
The taskforce observed a significant drop in nitrogen dioxide (NO2) levels that coincide with reduced traffic and industrial activity. (Shutterstock)
NASAâ€™s Orbiting Carbon Observatory-2 (OCO-2) satellite and Japanâ€™s Greenhouse gases Observing SATellite (GOSAT) tracked changes in CO2 emission in Mumbai, Beijing, Tokyo, and New York. The results show small, about 0.5 parts per million, or 0.125 per cent reductions in CO2 over each region.
Significant improvement in air quality
The taskforce observed a significant drop in nitrogen dioxide (NO2) levels that coincide with reduced traffic and industrial activity during three months of lockdown. Satellite data shows a reduction of 40-50 per cent in NO2 levels in Delhi and Mumbai between March 25 and April 20. However, the reductions were not consistent throughout India. “Observations over India also showed less air pollution during lockdowns in selected cities, such as New Delhi and Mumbai,” the taskforce said.
Northeast India showed nearly constant NO2 levels due to coal-based power plants, which did not reduce electric power generation significantly during the lockdown.
A notice put up at a barricade reads, ‘India Gate closed due to coronavirus’, to prevent mass gathering of tourists and locals amid fear of spread of the virus, at India Gate in New Delhi.
Similarly, in Madrid, Milan, Rome, and Paris, satellite data showed about a 50 per cent reduction in NO2 from March 13-April 13, 2020 compared to the same months the year before. These reductions coincide with the implementation of strict quarantine measures across Europe.
“Understanding the extent of any such changes would be important in maintaining global and local markets and food security as the world recovers from the pandemic,” Zurbuchen said.
The taskforce used the Tropospheric Monitoring Instrument (TROPOMI) on ESA’s Copernicus Sentinel-5P satellite and the joint NASA-Royal Netherlands Meteorological Institute (KNMI) Ozone Monitoring Instrument (OMI) on the Aura satellite to study the changes.
The joint Earth-observing dashboard can be accessed here.