I took this photo in my third year as a Peace Corps Volunteer Leader (PCVL) in 1996 during the Harmattan haze season in Niger, West Africa. Per Wikipedia, "the Harmattan is a dry and dusty West African trade wind. This northeasterly wind blows from the Sahara into the Gulf of Guinea between the end of November and the middle of March (winter). The temperatures can be as low as 3 degrees Celsius. On its passage over the desert it picks up fine dust particles." Notice how dusty the sky and air are. During a heavy Harmattan, you can barely breathe outside or see in front of you so it is best to stay put indoors until the trade wind passes usually within a few hours. I remember driving cross-country from the capital to Zinder Department as PCVL after my 2-year mark when I extended my service time. It was the Harmattan season and I had to pull over my PCVL Toyota truck to the side of the road and just sit and wait for the dust to pass. It can be very intimidating being caught outside.