millisphere (noun): A discrete region inhabited by approximately 1000th of the total world population.
'We live in a globalised world ... it can't be just goods, it's also human beings," said one African migrant in Libya heading for Europe.
March/April/May/June is the peak time for crossing the Mediterranean and it is estimated this year 200,000 Africans will cross the Sahara and 150,000 the Mediterranean.
Boundaries imposed by 19th century colonial powers divide the millisphere of the Sahara between Algeria, Tunisia, Libya, Mali, Niger and Chad.
If there is one group that can call the Sahara their home, it is the Tuareg (population two million), who traditionally carried high-value goods (salt, gold, ivory and slaves) from one oasis to another. The Sahara crossing by camel took about 40 days and today takes several days — 25 passengers to a Toyota pickup. Conflicts arise at the desert margins, where nomadic pastoralists meet sedentary agriculturalists.
It is thought more migrants travelling to Europe die crossing the Sahara than crossing the Mediterranean Sea, but back in 1982 when Bruce and Mary hitch-hiked across the Sahara, it was still safe for tourists.
"We didn't know where we were going, really," said Bruce, who lives in Whanganui's Aramoho suburb.
They arrived in Tunis by ferry from Sicily. An Algerian took them to the first oasis and, on a truck carrying vegetables, they took two days to get to Tamanrasset, in the middle of the Sahara.
The road to Agadez in Niger was littered with wrecked vehicles, Bruce recalled. Agadez is where African travellers from all over the Economic Community of West African States come to buy a ride to Tripoli in Libya.
The migrants are not dirt-poor farmers — you have to have money to travel. Typically, a family will scrape together a large sum to send a family member to Europe to send back remittances; as poor countries develop, their emigration rates rise.
The Tuaregs have historically shared the Sahara with other travellers, including Muslim traders, adventurers and black slaves. The millisphere of Sahara can be visualised as a road network, sometimes extending into surrounding millispheres, and 25 per cent of all Europe's cocaine crosses the Sahara.
The desert is advancing south into the Sahel at about 1km every two years. Planting a "green wall" of trees to halt the desert has been an expensive failure, although in Burkina Faso simple "water farming" techniques (trenches following the contours) and protecting trees that grew naturally have managed to re-establish some wooded areas.
Bruce and Mary crossed from Niger into Burkina Faso and then to the Atlantic coast of Cote d'Ivoire at Abidjan. In Mali (a burned-out 727 from Venezuela was recently discovered on a desert landing strip in Mali) they got within one ride of Timbuktu, but that meant waiting for days for passengers to fill the bus.
So back in Ouagadougou in Burkina Faso, they pulled the pin and flew to Lyon in France.
In the early 19th century, the French Geographic Society posted a reward of 10,000 francs for the first person to travel to Timbuktu — and back.
In 1825 British soldier Alexander Laing got there but was murdered two days later. In 1827 French butcher Rene Caillie got there and back and claimed the prize. The British thought Caillie was a "bad sport" for dressing in Arab robes and not full dress military uniform, as Laing had.
In Timbuktu there has been a collapse of foreign tourism because of armed Islamists, who have also targeted Tinariwen for playing "Satan's music". Tinariwen are a band of Tuaregs from Mali who played the Womad music festival in New Plymouth this year.
Jihadists attacks in Mali have sent refugees spilling into Burkina Faso, where job-seekers are now looking at the European Union and tomato picking in Italy, which has seasonal labour shortages.
Tinariwen are now living in the American southwest — in the Mojave Desert, of course.
■ When Fred Frederikse is not building, he is a self-directed student of geography and traveller, and in his spare time he is the co-chair of the Whanganui Musicians' Club.