According to the EPA, the small engines that power leaf blowers will account for 18 percent of smog-forming emissions by 2020, unless they are regulated.
In the fort's courtyard are several small wooden boats and traditional barasti (palm-leaf) houses, including the primitive Al Kaimah, and the summerhouse Al Areesh with traditional wind-tower (barajeel) "air conditioning".
In the thick forest-savannah mosaic of northern Congo, many days' walk from any tarmac, your correspondent unearthed a milestone, half-buried in the leaf-litter, pointing to the small town of Badai, 15km to the east.