Halloween Special: Constant Change

_{(3 min read)}

It is said that life is a constant change. If we step outside we often see only human-made changes. But there is monstrous change happen by Mother Nature that should be told at least as a scary story at Halloween!

Mother Nature is changing our environment all the time in a very subtle way. We are not referring to extreme weather phenomena that can change the appearance of the environment. We are referring to the constant movement of the surface. As geodata evangelist we love geodata and maps and also know that they are as good as outdated after getting recorded. But again, often these are human-made changes.

Everybody heard about plate tectonic but more or less doesn’t care about it (until hell is opening and volcanoes or earthquakes are applying changes). It is quite interesting to know that not before worldwide measuring was introduced in 1960, international societies were willing to agree on the concept of continental drift. The idea that our world isn’t fixed appeared at the end of the 19^th century and got prominently summarized and postulated by Alfred Wegener at the begin of the 20^th century. Decisive for that theory were the similar coastlines of Africa and South America as well as similar rock formations and diamond resources.

With upcoming satellite technology it was possible to start measuring the constant change of the world. With the help of monitoring fixed points all over the world using Global Navigation Satellite Systems as well as Satellite and Lunar Laser Ranging it was possible to create a geo-reference system for the whole world including the velocity of the change: the International Terrestrial Reference Frame (ITRF).

Including velocity? Ok, now we are interested to know which plate is the fastest one! The distance between the African and Eurasian Plate on the one side and the North and South American Plate on the other side increases by 2 and 3.5 cm every year. The Indian and Australian Plate diverges from the Antarctic Plate by up to 7.5 cm per year. Nevertheless the fastest race takes place in the Pacific: The Pacific Plate moves every year up to 15 cm away from it’s eastern neighbors the Antarctic, Nazca, Cocos and North American Plate. Imagine that after living ten years in the same house a 1.5 m wide no-mans-land appeared between you and your neighbors!

But this is just the horizontal movement; vertical motion also takes place. The northern part of the North American Plate gets lifted by 20 mm per year whereas the southern part subsides by 10 mm per year. Also the west and east edges of the Australian Plate drowns by approximately 12 mm per year. Scandinavia and Japan get lifted by 10 respectably 5 mm per year.

If you want to know the exact location of each plate you can use National Geographic’s Mapmaker to find out. Just add the layer “Tectonic Plates”.

These movements may look boring and only get thrilling if suddenly tension between plates unfolds (we call it earthquake). If we push the fast-forward button, however, these subtle changes tell also unexpected twists: The Indian Plate moves into the Eurasian one and will cause the Himalaya to grow the mountains by up to 7,300 m of height and will vanish completely beneath Tibet! Australia and New Zealand are moving northwards and the northern parts will reach the equator while the Iberian Peninsula will get ripped from Europe (in 20 million years). Africa moves closer to Europe and closes the Mediterranean Sea. Europe will break alongside the Rhine (in 40 million years). California will get ripped from North America and moves to the north whereas Greenland moves south to 60 degree of latitude (in 50 million years). Meanwhile Africa will have created a mountain range in the location of the former Mediterranean Sea and Australia will crash into Japan followed by Antarctica (in 80 million years). North and South America will be split but the north will move south next to the South (in 90 million years). At the end Greenland will reach the same geographical altitude of Peru at 30 degree of latitude (in 150 million years). Mexico will cross the equator towards Antarctica; East Africa will collide with the rest of India; New Zealand will be close to the equator and South America will be rotated by 90 degrees clockwise (in 200 million years). At the end the world as we know it will be totally garbled!

Now scared? You should! Mother Nature is always stronger than you; that’s why you must not mess with Mother Nature! With focus on plate tectonic we still have enough time to prepare the “treat” before we get tricked (whereas we are running out of time on other issues). Nevertheless, GEONATIVES wish everybody a Happy Halloween!