Satellite images show city lighting up thanks to recovery

Shanghai is getting more "light at night"  with an increasing number of stores and restaurants reopening, as well as employees returning to work in commercial buildings, as the coronavirus pandemic is waning in China, a research from the city's Surveying and Mapping Institute shows.

The institute analyzed data on the brightness and distribution of the city's nighttime light collected by remote sensing satellites and found it is now brighter.

Wang Sijian, an engineer at the institute, said its research team compared the data they collected at 8pm on February 4 and April 7. It found the brightness in April is some 24 percent higher.

Xin Liang, deputy head of the institute's No.3 branch, said that unlike visible light satellites and radar satellites, the remote sensing satellites for nighttime light can collect near infrared wave information, which is emitted by human activities.

Nighttime light remote sensing is playing an important role in analyzing the expansion of city as well as fields related to human activities.

The research shows the Lingang Special Area of the China (Shanghai) Pilot Free Trade Zone became brighter in the past two months with workers back to their positions and factories resuming  production.

In February, the Donghai Bridge was almost dark at night but two months later it is a bright line on the image.

Also there was no obvious network of roads from Shanghai to its neighboring regions. But now, a bright "cobweb" of light surrounds the city.