A study published in the journal Nature Communication shows that the speed of geomagnetic field switching direction is likely to be 10 times faster than previously thought, and may be reversed within 100 years.
It is very likely that some people don't know what the earth's magnetic field is and how it is produced. A simple statement is that we can regard the earth as a big magnetic bar, and the magnetic field around the big magnetic ring is the earth's magnetic field. There are many different names about the cause of the earth's magnetic field in academic circles, but they all have one thing in common: it is caused by shape memory alloy fitness exercises everywhere. Therefore, it cannot be changed by human factors. However, due to fitness exercise, it changes all the time, and every once in a while, it is another "Antarctic becomes the Arctic Circle".
But the reversal of magnetic poles can not be completed in two years, and it may take thousands or tens of thousands of years. According to biologists' calculations, in the past 65.438+0.5 billion years, the earth's magnetic poles have turned over hundreds of times at different frequencies. The earth's magnetic pole rotates every few hundred thousand years. The last time the Earth's South Arctic Circle flipped was about 780,000 years ago.
Dr ChristopherDavies, an associate professor at the School of Earth and Natural Environment of Leeds University, UK, and CatherineConstable of the University of California, San Diego, USA, made a simulation based on an outer core made of nickel and iron about 2800 kilometers (1740 kilometers) below the earth's surface. Combining closely with the timetable of the earth's magnetic field before 100000, a result is obtained: the azimuth transformation rate of the earth's magnetic field is likely to be 10 times faster than previously thought (moving at the rate of 1 degree every year), and it may turn over in the last hundred years, and the azimuth transformation seems to be consistent with the local weakening of the magnetic field.
Richardson said: "400 years ago, people's mastery of the magnetic field was still very incomplete. Because this rapid change means some extreme personal behaviors in the center of the earth, they can give important information about personal behaviors in the deep earth. "
However, the interaction between magnetic poles and magnetic fields is complex, and their series of mobility effects will make some areas have strong zonality, while others are weak. For example, there is a strong magnetic field at high latitudes and a weak magnetic field at low latitudes.
In their scientific research, the most striking example is that 39,000 years ago, the direction of the geomagnetic field changed dramatically at a rate of about 2.5 degrees per year, which led to the weakening of the compressive strength of some magnetic fields in the Gulf region of central and western South America at that time. However, there is a long-term weak magnetic field in the contemporary earth-the South Atlantic anomaly in the eastern hemisphere. The compressive strength of the magnetic field in this area has dropped from 24000nT to 22000nT in the past 50 years, so that communication satellites and detectors passing through this area will find anomalies.
In addition, research shows that in the past 200 years, the compressive strength of the earth's magnetic field has weakened by 9%. But even if the earth's magnetic field is weakening, it will not weaken, and it will not weaken easily within several 65.438 billion light years. What will happen if the earth's magnetic field disappears one day? At first, many charged sunlight particles immediately negatively charged the earth's surface, and the life of the earth was exposed to high-quality carcinogen ultraviolet radiation. Navigation in modern society is lost, and birds and small animals moving by magnetic induction magnetic field are at a loss ... The problem will appear in a short time, but there is no doubt that this is not the end of the world. But there is no doubt that there will be the extinction of life, and it is hard to say whether there will be an atmosphere of the earth.