South Atlantic Anomaly weakening Earth magnetic field seems to splitting - Curiosity Streamer

                            South Atlantic Anomaly

The earth’s magnetic field also known as “geomagnetic field” is an invisible force field that extends from the Earth's outer core to space exerting a force on the charged particles emitted from the Sun. It protects us from the cosmic radiations emitted from sun and other cosmic bodies. It gets stretched out into a tail like field that stretches millions of miles in the opposite from the Sun. 

 The magnetic field is nothing but an electric currents pulse generated due to the motion of convection currents of a mixture of molten iron and nickel in the Earth's outer core. This convection current is caused by heat escaping from the core, a natural process called a geodynamo. The outer core lies below our ground around 3,000 km. It creates electric currents that generate and change our electromagnetic field. The rotation of the Earth creates movements inside the liquid outer core which gives rise to the geomagnetic field.

                                                                  

Earth’s magnetic field weakening:

Scientist at the European Space Agency observed that the Earth’s magnetic field is gradually weakening in the areas between South America and Southern African regions. This effect is causing technical disturbances in some satellites orbiting the planet. But, this present fluctuation intensity is within normal fluctuation levels.

Some researchers state that it may due to the magnetic polar shifting. To strengthen this fact coincidentally, the North Magnetic Pole of the Earth has also shifted in recent years. It is moving away from Canada towards Siberia in Russia. The pole will continue to move towards Russia but, in a slow time being. At top speed, it's moving around 50-60 km a year.

In last 200 years, the electromagnetic field of around Earth has lost around nine per cent of its strength. Between 1970 and 2020, the magnetic field of Earth has weakened considerably in the region stretching from Africa to South America, which is termed as the ‘South Atlantic Anomaly’. This weakening area of magnetic field is growing and moved westwards at a rate of around 20 km per year.

The other possibility is Pole reversing. The magnetic field isn't as neat straight and tidy as the one created by a normal bar magnet in hand. It has areas of strength and weakness. Sometimes, it even flip-flops with north and south switching places. The North and the South Poles may be switching. Such geomagnetic reversals happens roughly every 2,50,000 years and given the last one took place 7,80,000 years ago.     

                                                                   

                

However, a study published in the scientific journal Proceedings of the National Academy of Sciences in 2018 found that despite the weakening field, "Earth's magnetic field is probably not reversing". The reason given that is the reversal of a magnetic field will take tens of thousands of years for occurring.

The current weakening of the Earth's magnetic field could portend another one of these flip-flops or may be it could be a simply temporary fluctuation. If the field does reverse, the South Atlantic Anomaly is likely to be the origin of the change.

"The new, eastern minimum of the South Atlantic Anomaly has appeared over the last decade and in recent years is developing vigorously," Jürgen Matzka, from the German Research Centre for Geosciences said in a statement.

Effect of the Anomaly:

The magnetic field protects the life on earth from all harmful comic radiations and it also acts as a natural system of navigation for birds, animals and even humans in many cases. It also protects us from the solar storm that could damage entirely all the electric systems on the earth.

It will affect creatures like turtles, birds, etc..., because they entirely depends on geomagnetic field for navigation and migration. 

This magnetic weakening causes all the satellites and spacecrafts orbits around the South American and African region. Even it affects the ISS (International Space Station). Since the GPS satellite is a chain of satellite conducts the whole world, it leads to a global scale technical disturbance. By effect, the navigation systems and mapping functions in smart phones may be affected.

The telecommunication and satellite systems also rely on the geomagnetic field. Therefore, computers, mobile phones and other devices could also face difficulties. South in the compass could point to Canada and North to Antarctica.

ESA's Swarmconstellation of satellites  launched in 2013 is probing the anomaly for small changes that could explain what's going on in the core. The challenge that lies ahead is to study the reason behind this change. Since the group of satellites went into orbit, the South Atlantic Anomaly has developed a second center of minimum magnetic intensity in the southern African region. This second weak spot indicates a complex process in the Earth's core, north-south magnetic field can't explain the pattern, and this is the statement reported by ESA in a press release.

                                                                         

"This change in the pattern of flow has weakened the patch under Canada and ever so slightly increased the strength of the patch under Siberia… This is why the North Pole has left its historic position over the Canadian Arctic and crossed over the International Date Line. Northern Russia is winning the 'tug of war', if you like," Dr Phil Livermore told BBC News.

                                                    

                                        

Article contributed by Johith Gandhi