A haboob (Arabic: ÙÙØ¨ÙØ¨ â habÅ«b blasting/drafting) is a type of intense dust storm carried on an atmospheric gravity current, also known as a Weather Front.Haboobs occur regularly in arid regions throughout the world. haboob approaches Taji, Iraq, in 2006. A haboob hits the South-East Valley, Gilbert, AZ, USA, on 5 July 2011, around 7 p.m., hiding San Tan Mountain completely.
applying a blood choke means locking the opponents neck in a restrictive manner to cut the blood flow from both the Perotid and Carotid arteries in the neck as philip has said. but with the links he's also provided, it should help fairly well.
What I've picked up over the years about how blood chokes actually work - and I could be wrong - is this: There's a nerve in the neck called the Vagus nerve. One of its many functions is to sense blood pressure of the arteries in the neck.