Like a big forest fire Raging Eastern Australia In January 2020, Deadly haze Settling in Melbourne, this is a clear sign that residents stay indoors. However, the beating signals on their heads are not so obvious: cellular data is flying in the air in a strange way, and scientists may be able to use it to better understand and predict future severe smog events.
Cell signals over Melbourne interact with an atmospheric phenomenon called temperature inversion. Generally, you will find higher temperatures near the ground, where the sun is heating the ground, and lower temperatures in the atmosphere. However, as the name suggests, temperature reversal can solve this problem.
When a layer of smoke rolls over the city, it absorbs the energy of the sun, thereby preventing most of the radiation from heating the surface. This creates a layer of hot, dry, smoky air that sits above the lower air on the ground. Atmospheric scientist Adrien Guyot of Monash University said: “You have a double process” paper In the diary AGU progress Describe the research. “You have preheated the floor, and the fact is that the ground is not heated as usual.”
This does make the signals transmitted between the cellular antennas on top of Melbourne buildings a bit strange. (Guyot and his colleagues are specifically studying antenna-to-antenna communication in the network, not how people’s mobile phones connect them.) Usually, when these antennas talk to each other, the signal more or less travels directly between them. But temperature inversion will produce a kind of upper atmospheric limit, which makes the signal bend sharply toward the ground.
These are called “abnormal propagation conditions”, which means that the signal will propagate abnormally. It will bounce off the ground, then rise again, then bounce off the ground, and then rise again. So it will fall into the inversion layer. “Guoyt said. Because the signal is beating, the propagation time between the antennas is different from the propagation time when the path is straighter under normal conditions. Guyot added: “And because it does not always arrive at the same time, sometimes your reception The number of people is high, and sometimes your reception is small. “The signal is really clear.” “
Then, by looking at this cellular data, Guyot can determine when the temperature reversal over Melbourne will be set during the wildfire season in Australia. In addition to capturing these signals, the inversion layer also captured smoke, so a data record was created as the air quality of the city became the air quality of the city. Worst in the world. Guyot believes that in the future, those cell signals may be monitored to obtain indications as to where the reversal may be formed and its severity. This will allow officials to better understand the rate at which air quality may decline. Guyot said: “If the temperature reverses, and this reversal is intensifying, then the smoke concentration will also increase.”
Imagine dumping coloring materials in children’s pools and Olympic pools. Even with the same amount of dye, you will get darker water in smaller waters than in larger waters. In contrast, smoke that spreads more widely in an open atmosphere, as well as condensed smoke trapped in a thin layer of air close to the ground. Rebecca Buchholz, an atmospheric chemist at the National Center for Atmospheric Research, said: “These reversals mean that smoke will not be transported to higher altitudes,” and he was not involved in this new work. “Therefore, it is close to the ground, highly concentrated, and there is more pollution on the ground that will affect humans.”