BEIJING - Thick brown clouds of soot, particles and chemicals stretching from the Persian Gulf to Asia threaten health and food supplies in the world, the U.N. reported Thursday, citing what it called the newest threat to the global environment.

The regional haze, known as atmospheric brown clouds, contributes to glacial melting, reduces sunlight, and helps create extreme weather conditions that impact agricultural production, according to the report commissioned by the U.N. Environment Program.