Istanbul Technical University (ITU) Satellite Communications and Remote Sensing Center (CSCRS), a new type of coronavirus (Covid-19) prior to the outbreak and after images taken by satellite, measures to that followed, crowded square in Turkey, visibly the coastal road and thoroughfare in a revealed that it was emptied in the way.
The mobility in the square, the beach and the streets has come to a halt
In the records taken on the beaches of Kadıköy, Üsküdar and Eminönü in Istanbul on March 1-9 and April 9, it was noted that the density of vehicles on the roads and parking lots decreased significantly, while the mobility came to a standstill.
It was observed that the rules were largely complied with in Zincirlikuyu and its connected roads, around Maslak and Büyükdere Street, and fewer vehicles came into the traffic.
While Taksim Square and İstiklal Street were quite crowded in the image taken on March 1 before Kovid-19, it was noteworthy that the density of people decreased by finger in the image recorded on April 9.
Mobility at bus and train terminals stopped in Ankara
In the image taken on April 14 in Kızılay Square and its vicinity in Ankara, it was noted that the density of vehicles and people decreased significantly.
When the images taken between the Ankara Intercity Terminal Operations (AITO) and the High Speed Train Terminal and its surroundings were compared between 17 January and 14 April, it was observed that the number of buses waiting for passengers in the area decreased almost negligently after the intercity travels were banned.
In addition, it was observed that the traffic and vehicle density on the roads connecting to the terminals was very low.
Izmir remained empty on the day of curfew
Comparing the image taken on April 12, when the curfew was imposed on the coasts of Izmir Kordon and Alsancak and the image on February 18, it drew attention that the coastal road and the parking lots in the vicinity were almost completely empty.
The decrease in the density of vehicles on the roads was reflected in the images taken around Bursa Ulu Mosque and the Grand Bazaar between 9 March and 13 April.
In the image recorded in Konya Mevlana Square on April 8-10, it was seen that the density of vehicles was slightly higher than other provinces.
Number of parked planes increased at airports
The images taken between 9 March-9 April at Atatürk Airport and 22 January-20 March at Istanbul Airport were compared.
Both satellite images recorded at the airport, and the suspension of international flights to domestic flights in Turkey and throughout the world are also almost been observed to increase the number of aircraft at airports that are in the park due to come to a halt. Parked planes were marked with an image processing algorithm.
Air quality improved
On the other hand, the effects of Kovid-19 on the change of air quality were also observed in the satellite shots made within the scope of the study.
The 3-day averages of the changes in nitrogen dioxide concentrations after Covid-19 were taken with the Sentinel 5P satellite in the Marmara Region-Istanbul, Aegean Region-İzmir, Central Anatolia-Ankara and Konya and the Mediterranean Region.
In the images, it was noticed that nitrogen dioxide concentrations in the air decreased greatly, while it was observed that they increased occasionally in port areas. It was stated that nitrogen dioxide values decreased on the weekend and increased on weekdays, while air quality and cleanliness increased on days when the values decreased.
“More rules have been followed in recent weeks”
ITU CSCRS Director and Civil Engineering Faculty Geomatics Engineering Department Lecturer Prof. Dr. Elif Sertel AA correspondent, founded the center of the support of the State Planning Organization in 1996, it is Turkey’s first satellite earth station, several antenna systems and equipment that infrastructure, contracted their satellite directly from data downloads and that they have the right to plan for receiving data told.
Pointing out that after the Covid-19 epidemic, especially with the introduction of some measures for curfew and the implementation of the weekend curfew, the mobility decreased as expected in many places, Sertel said that they are planning to view the effects of the decrease in human and vehicle mobility from space via satellite.
Stating that they recorded images, some of which are on weekdays and some on weekends, especially in the busy squares, beaches and airports, Sertel explained her observations as follows:
“Especially the squares filled by people in good weather are completely empty with the effect of Covid-19 and the curfew. There are examples we have taken from Üsküdar and Eminönü coast, İstiklal Caddesi and its surroundings. The images we took from the Izmir coast coincided with the Sunday when the curfew was imposed. And when we compare it with the latter, we no longer see cars, especially in places where people go out a lot and use parking lots, parking lots are empty.It is possible to observe that vehicle traffic is not the same as it used to be on the roads and streets that are used a lot. By combining it, we can follow the condition of the mobility, decrease-increase, sometimes even if the rules are followed. It is possible to infer information from the images that the rules are followed better in the last weeks. “
Capturing images from a distance of 700 kilometers
Stating that they download very high resolution images from the satellites they have contracted with, Sertel said, “These are spatial resolution ranging from 30 centimeters to several meters. A pixel you see in the image can correspond to 30 to 50 centimeters on the ground depending on the type of satellite. This means the detail you can distinguish. Resolution 2 These satellites are 600-700 kilometers away. It is an important technology to be able to access this detail from that distance. ” made its evaluation.
“Covid-19 positively affected air quality”
Sertel explained that nitrogen dioxide is a substance found in the air, its excess indicates the air pollution, it generally increases during the winter months, and especially the emission gas from vehicles and the coal used for heating cause an increase.
Stating that they also monitor the atmosphere with the satellites of the European Space Agency, Sertel gave the following information:
“They have a system for air quality. We download data from there to see if there has been a change in air quality. Because factories are closing with the effect of Covid-19, traffic is decreasing. This positively affects air quality. With such less activity, pollutants such as sulfur dioxide are in the atmosphere. It is not happening anymore or very little. It is possible to observe this mobility. For this, we can make animated videos using the satellites of the European Space Agency and we can interpret how the air quality has changed at different times. At times, the amount of nitrogen dioxide decreases and the air becomes cleaner. Our observations are generally consistent with this. When you look at the before and after Covid-19, there is a good, positive improvement in air quality.