The combustion of fossil fuels, wood, and other biomass increases the amount of airborne particles, which, in a somewhat simplified manner, we can describe as “white” or “black.” Both types can be found in varying amounts in all emissions.
燃烧化石燃料、木材和其他生物物质会增加“黑”、“白”两类空气悬浮颗粒。所有排放中均含有数量各异的这两种物质。黑色颗粒大多来自小规模、低能效的生物燃料燃烧，也可能来自亚洲和非洲的农业废弃物焚烧。相比之下，白色颗粒则主要来自于燃烧煤和石油所产生的硫。