Throughout her history, the Earth’s climate has been fluctuating between hot and cold, ‘greenhouse’ Earth and ‘icehouse’ Earth. When the asteroid hit our planet 65 million years ago, Earth was in a greenhouse period but with the continents moving into their current positions, it started cooling. A new geological era opened. Flowering plants evolved. The main new feature, however, appeared in the fauna: After the Age of Reptiles with its dinosaurs and crocodiles, the Age of Mammals began. – That’s us. And 36 million years ago, the Earth slipped into an icehouse period with the Arctic and Antarctic ice sheets and the glaciers building. Our current Ice Age began. Within an ice age there are glacial periods, cool and dry, in which the continental ice sheets and the glaciers grow, and there are interglacial periods, warm and wet, in which the ice sheets and the glaciers melt. The exact causes for ice ages, and the glacial cycles within them, have not been proven. They are the result of complicated interactions between such things as solar output, orbital distance of the Earth from the sun and her rotational spin, tectonic movements, changes on the surface of the Earth and in the ocean circulation, and the composition of the atmosphere. At least the Antarctic ice sheet has been there ever since our Ice Age began and as long as there is ice on the planet, we remain in that Ice Age.
Around 2.6 million years ago when Homo habilis emerged, a period of repeated longer glaciations started and alone since the emergence of Homo sapiens 200’000 years ago, two cold glacial periods and two interglacial warming periods have occurred. The second interglacial warming period started as recently as 12’000 years ago and is ongoing today. According to the orbital rhythm of the Earth around the sun, the next glacial period is not expected before another 50’000 years from today. – If we humans with our population growth and greenhouse gas emission don’t establish permanent global warming and end the Ice Age altogether. The Earth’s climate is today warming at an unprecedented speed in the very, very long history of our planet. The end of the Arctic Sea ice seems a question of years and it is hard to believe that the Antarctic ice sheet will survive very much longer, sharing Earth with us humans. The end of the Ice Age is nigh!
The physical features of the world, however, have barely changed in the short time that humans have appeared. No continental plates have shifted, no new valleys have collapsed, and no new mountains have grown. Some volcanoes have erupted, and others have gone cold. And due to the climatic changes over the millennia, the oceans have risen and fallen, and some glaciers, lakes and rivers have come and gone. Overall, Africa as our ancestors experienced it was barely different from as we know it today. Only that we have given names to the natural appearances, and we have made maps and drawn lines into them, dividing the continent into geographical areas, climatic zones, time zones, and countries. All these lines will now help us to understand the immense size of Africa.
In New York, when I learned that my next posting would be Nairobi, in cocktail-party small talk, I mentioned to an American friend that I would be going to Africa. “Oh, that sounds like an interesting country. Maybe I will come and visit you, one day.” I left it there and he never came. But here, I have to say, that’s not how it is. As you will see on any world map that you open in an atlas or on the internet, Africa is in the middle of the world. And Africa is not a country, it’s a continent. And a big one at that. The African continent covers more than 30 million square kilometers. This is more than three times the United States of America. Or three times China. Or almost seven times the European Union, in which I have – politically completely incorrect – not accounted for Brexit and included the 41’000 square kilometers of Switzerland. And Africa counts 55 countries. This is five more countries than America has states or double the countries of the European Union. Africa is big.
The Equator is one of the principal lines that we have drawn onto the world map. It has a physical explanation which has to do with the rotation of the planet around its axis, defined by the two poles. It is the baseline of the parallels of longitude and cuts the Earth into a northern and an equal southern hemisphere. The Equator has been calculated and used for global orientation ever since the ancient Greeks. The North Pole of the Arctic is at 90 degrees north and the South Pole of the Antarctic at 90 degrees south of the Equator. And the areas 23.5 degrees or 2’600 kilometers north and south of the Equator are the Tropics. North, the Tropic of Cancer, and south, the Tropic of Capricorn. The vast part of Africa lies in the tropics. While the United States and Europe don’t even touch them, Africa reaches from the temperate climate zone of the northern hemisphere all the way through the Tropic of Cancer and the Tropic of Capricorn into the temperate zone of the South. And it is the only continent to do so.
Beyond being the baseline for defining the northern and southern hemispheres and tropics, the Equator has real life consequences. In 1981 for my transfer from Switzerland to Zaïre, the rules and regulations of the Federal Department of Foreign Affairs were still on paper and in folders. There, I found in the footnote to one regulation that I could do the trip by boat. The elderly administrator at the Travel Section first denied, since ‘Swissair’ now flew there, this was no longer possible. I argued that it was written and showed him the footnote. He gave in and grumped that I would be the last one. Imagine! For my first posting abroad as a young diplomat, I would drive my brand-new Subaru 4WD to Antwerp, load it on a Zairian freighter, spend eleven days on board, unload my Subaru at Matadi, the Congolese port in the mouth of the mighty Congo River, and drive my way up to Kinshasa. – Toward the end of the passage on the ‘Kananga’, the captain asked me whether I had ever crossed the Equator before. I answered in the negative. “Good”, he said, I would join three sailors in the ritual of the Crossing-the-line Ceremony. First, they hosed me down with sea water. Then, I had to go to my knees, and they tied my hands behind my back and put in front of me a half full bucket of water with an apple floating on it. I was told to remove the apple from the bucket, without spilling the water. The top part of my head under water, with my cheek and chin, I pressed the apple against the inside of the bucket, carefully turned my head and bit in it. Proudly lifting my head out of the bucket, apple in mouth, the captain applauded me but asked, why I had not simply used my hands behind the back. Finally, I had to pull a dead fish from the bottom of the water in the bucket, with my teeth. This time, hands would not have been allowed. You have no idea how salty the water of the Gulf of Guinea is. When I did the return trip to Switzerland with the Kananga again, I was happy that I didn’t have to repeat the ritual of the Equator-crossing. But I had to take the time of the trip as vacation. The administrator had changed the regulation. Nevertheless, because it was cheaper than the Swissair flight, the Department paid for it.
From the Indian Ocean and the most southern part of Somalia to the Atlantic Ocean, the Equator crosses East and Central Africa, over about 3’300 kilometers. Nairobi, where I live, is 200 kilometers south of the Equator. On the Equator in Nanyuki on the western foot of Mt Kenya, where my wife has a piece of land and has planted a forest on it, the local souvenir artisans know about the physical consequences of the Equator. Around the Equator sign board where they sell their handicraft, they demonstrate to you the effect of the Coriolis force. When they release the water through a hole in the bottom of their basin ten meters north of the sign board, the matches floating on the surface of the water turn anti-clockwise. And clockwise ten meters south of the sign board. Under the sign board, the floating matches stand still. I have seen the trick one hundred times, in groups with friends and alone, and I still don’t know how they do it. And in the 1990s when tourism in Kenya was flourishing, fifty meters north of the Equator I still visit today, there was a second Equator, where they performed the same trick. The Coriolis law affects the large physical phenomena over thousands of kilometers, like ocean streams. Or the regular cyclones I saw sweeping into Madagascar from the Indian Ocean – in the southern hemisphere, all turning clockwise. Not basins of water, toilets, or bathtubs. Just to be sure, I checked my toilets in Nairobi. The flush of one of them whirls clockwise, the others anti-clockwise. By the way, in Nanyuki for a small surcharge, you can get an ‘Equator Crossing Certificate’ with your name and the date of your crossing on it. For the initiation ritual I was party to on the Kananga, I never got a certificate.
Kampala, the capital of neighboring Uganda on the northern shore of Lake Victoria to the West of Kenya, is slightly north of the Equator. From Uganda, the Equator crosses both Congo-Kinshasa and Congo-Brazzaville, and further west, from the name of the country you would expect Equatorial Guinea to be on the Equator, but it isn’t. The Equator hits the Gulf of Guinea on the coast of Gabon to its South. Then it goes into the sea. The small island state of Sao Tomé and Principe is on it. In the Atlantic, the Equator follows the West African coastline for another 2’000 kilometers, always around 500 kilometers south of it. From Dar es Salaam, the Indian Ocean capital of Tanzania, to Dakar, the capital of Senegal and Africa’s most western city on the Atlantic Ocean, the crow flies 6’600 kilometers and crosses the Equator. For comparison: From New York to San Francisco, it is 4’100 kilometers and if you take Route 66, as I did with my Chevrolet Station Wagon in the eighties, it is maybe a few hundred kilometers more, but still only two thirds of Dar es Salaam – Dakar. From the Ukraine in Eastern Europe to Lisbon in Portugal on its most western coast, it is half that distance, 3’400 kilometers. Africa is big.
Talking about Dar es Salaam in the East and Dakar in the West of Africa, has it ever occurred to you that in Tanzania you will never see a sunset over the ocean? Whereas in Senegal you will never see the sun rise over it. But there is another East and West than the one of sunrise and sunset, and the rotation of the Earth around the sun. To measure the round of the world from East to West, the British invented the meridians of latitude that run from North to South and drew them onto the world map. Contrary to the Equator, the Prime Meridian is not defined by any physical features, it was set at will by the Royal Observatory in Greenwich which determined that its geographical position would define the baseline, at zero degrees. This had to do with London being the capital of the sea-faring British Empire and the ‘Rule Britannia!’ of the 18th and 19th centuries. Together with the anti-meridian, at 180° latitude and running through the mid-Pacific Ocean on the other side of the world, the Prime Meridian forms the circle that divides the Earth into the eastern and western hemispheres. And to this day, maritime navigation, GPS and all the location apps on your smart phone operate with coordinates of the 90° north or south of the Equator and the 180° east or west of the Prime Meridian. In the 20th century, it turned out that the Royal Observatory was actually 0.0005° West. And the British Empire having been disbanded, Rule Britannia! became ‘Cool Britannia!’, celebrating modern Britain as a stylish nation of music, fashion and mass-media diffusing culture and entertainment. The English Premier League is one of those global franchises. It allows me to watch the games of Liverpool Football Club, sitting in my armchair in Africa – where the Prime Meridian runs through Algeria, Mali, Burkina Faso, and Ghana. So, parts of these countries and their neighbors to the West, namely Morocco, Western Sahara, Mauretania, Senegal, The Gambia, Guinea-Bissau, Guinea, Sierra Leone, Liberia, and Côte d’Ivoire, all lie in the western hemisphere. But this makes only for about a fifth of the continent. The other forty countries lie in the eastern hemisphere. Africa is big.