Playing charades with my nine-year-old over the weekend, I was surprised when he gave black smoke as a clue for diesel. When I was his age, I probably would have given bus or truck as a clue.
The word diesel derives from the inventor Rudolph Diesel, who developed a heavy-duty engine in Germany in the late 1800s. Diesel fuel is any fuel used in diesel engines. The combustion of diesel fuel provides the power to move heavy-duty vehicles, such as buses and trucks. It also results in emissions of fine particles, often in the form of black smoke, along with a number of other chemical compounds.
In 2012, the World Health Organization (WHO) declared the emissions from diesel combustion to be carcinogenic. Last month, the WHO released data showing that more than 7 million deaths are caused by indoor and outdoor air pollution. The black smoke from diesel engines is a part of outdoor air pollution contributed by buses and trucks, as my son would tell me after we finished our game.
What he does not know as yet is that a study by a team of international scientists in 2013 noted that diesel smoke consists primarily of black carbon, which has a strong global warming impact on the climate; nearly 3,300 time more than that of carbon dioxide over a 20-year time period.
The one simple and clear message from the triangulation of current scientific evidence is that reducing diesel emissions provides health and climate benefits.