India sends blackbox of crashed C-130J to US for decoding data

Washington, Apr 23: Air pollution over northern India has plummeted to a 20-year-low for this time of the year, according to satellite data published by US space agency National Aeronautics and Space Administration (NASA).
The US space agency's satellite sensors observed aerosol levels at a 20-year low post the countrywide lockdown, implemented to slow the spread of the novel coronavirus.

"We knew we would see changes in atmospheric composition in many places during the lockdown," said Pawan Gupta, a Universities Space Research Association (USRA) scientist at NASA''s Marshall Space Flight Center. "But I have never seen aerosol values so low in the Indo-Gangetic Plain at this time of year," added Mr Gupta.

Acting Assistant Secretary of State for South and Central Asia Alice G Wells tweeted, "These images from NASA were taken each spring starting in 2016 and show a 20-year low in airborne particle levels over India. When India and the world are ready to work and travel again, let's not forget that collaborative action can result in cleaner air."

The data published with maps show aerosol optical depth (AOD) in 2020 compared to the average for 2016-2019. Aerosol optical depth is a measure of how light is absorbed or reflected by airborne particles as it travels through the atmosphere.

If aerosols are concentrated near the surface, an optical depth of 1 or above indicates very hazy conditions. An optical depth, or thickness, of less than 0.1 over the entire atmospheric vertical column is considered "clean." The data were retrieved by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite.

In the first few days of the lockdown, it was difficult to observe a change in the pollution signature. "We saw an aerosol decrease in the first week of the shutdown, but that was due to a combination of rain and the lockdown," said Mr Gupta.

Around March 27, heavy rain poured over vast areas of northern India and helped clear the air of aerosols. Aerosol concentrations usually increase again after such heavy precipitation.

"After the rainfall, I was really impressed that aerosol levels did not go up and return to normal. We saw a gradual decrease and things have been staying at the level we might expect without anthropogenic emissions," Mr Gupta said.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The countrywide mandate decreased activity at factories and severely reduced car, bus, truck and airplane traffic. Every year, aerosols from anthropogenic (human-made) sources contribute to unhealthy levels of air pollution in many Indian cities.

Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart.

In southern India though, the story is a little hazier. Satellite data show aerosol levels have not yet decreased to the same extent. In fact, levels seem to be slightly higher than in the past four years. The reasons are unclear but could be related to recent weather patterns, agricultural fires, winds or other factors.

"This a model scientific experiment," Robert Levy, program leader for NASA's MODIS aerosol products, said about the lockdown and its effects on pollution.

"We have a unique opportunity to learn how the atmosphere reacts to sharp and sudden reductions in emissions from certain sectors. This can help us separate how natural and human sources of aerosols affect the atmosphere," Mr Levy added.

New Delhi, Jun 30: With a spike of 18,522 COVID-19 cases in the last 24 hours, India's coronavirus count now stand at 5,66,840, said the Union Health and Family Welfare Ministry on Tuesday.

According to the Ministry, 418 deaths due to COVID-19 were reported in the last 24 hours. The number of deaths in the country now stands at 16,893.

There are 2,15,125 active coronavirus cases in the country while the number of cured/discharged patients stands at 3,34,821 and one patient migrated.

As per the Ministry, Maharashtra is the worst-hit state with regard to the COVID-19 cases and has reported 1,69,883 cases, including 73, 313 active cases 88,960 cured/discharged patients and 7,610 fatalities.

Tamil Nadu has a total of 86,224 cases including 1,141 deaths. Delhi's COVID-19 count stands at 85,161 cases and 2,680 fatalities.

The total number of samples tested up to 29 June is 86,08,654 of which 2,10,292 samples were tested yesterday, informed the Indian Council of Medical Research.

Eminent river engineer and former professor of civil engineering at IIT in the Banaras Hindu University (BHU) Prof. U.K. Choudhary has said that the judicious use of river technology can help resolve the Coronavirus crisis as well as the plight of Ganga river.

Choudhary, who is also founder of Ganga Research Centre at IIT (BHU), said: "The Ganga water contains a significantly higher proportion of bacteriophages - a kind of virus that kill bacteria. Our ancient scriptures like Vedas, Puranas and Upanishads say that Ganga jal is medicinal water. Scientists later found that Ganga water has bacteriophages capable of killing pathogens."

Explaining further, he said, "Let us analyze the source of bacteriophages. If we take three rivers of Himalayan origin having sources at different heights -the Ganga (Gomukh), Yamuna (Yamunotri) and the Sone river, we find the colours of waters are different. The whitish colour of Ganga water, greenish colour of Yamuna water and the brownish colour of Sone water is also indicative. As Gomukh is the highest among the three, its water comes from lowest depth of aquifer as compared to Yamunotri and Sone river," he explained.

Thus, the quality of river water is proportional to height of origin point. This defines the genetic character of Ganga water. The balanced flow of this water in entire length of the Ganga defines the medicinal property of Ganga water," he stated.

Prof Chaudhary said that the bacteriophages in the Ganga can curb the spread of coronavirus through soil, water and air.
He suggested that the idea is to preserve the medicinal value of Ganga water and to use it to fight Corona. He said that this can be done by opening the gates of all the dams and barrages in a way that the discharge through each is similar to the water at Gomukh. In this way, the concentration of bacteriophage will be enhanced in Ganga water making it more effective against pathogens.

"With increasing diffusion of bacteriophages in water and soil, the spread of Coronavirus will be impacted and reduced. This methodology and technique can also help maintain the quality of Ganga water later when the problem of Corona ends," he said.