Why does a truck's diesel exhaust smell stronger in the winter than the summer?

Answer 1

they have different blends of fuel for winter and summer diesel and petrol!

different hydrocarbons (longer chains in summer so that its volatility isnt so great it disappears when you pour it into the vehicle and longer in winter so that it doesnt sludge into the gas tank!)

they also add in different chemicals to increase the efficiency of the fuel in winter, for example higher levels of nitrogen so that a larger quantity of nitrous oxide is produced and you get a bit more kick!

Answer 2

I'm pretty sure it's because of the cold winter air. Just like your breath, the diesel exhaust condenses as soon as it hits the cold air which makes it heavier, keeping near the ground, where you can smell it. In the summer, the "thicker" warm, humid air makes it harder to smell, and causes the exhaust to rise and disperse. It might also be that they use a different fuel mixture in the winter to prevent gelling.

Answer 3

It's because in general your nose is more sensitive to smells in the cold than in the heat.

In the wintertime, the air is generally drier, thus your mucous membranes are covered with less "wet crud" (and in my case, more "dry crud").

The air is also more dense and compact in colder weather, allowing your olfactory senses to get a more dense whiff of whatever it is you are smelling.

Try this: stand outside for 10 minutes (in the winter)... then blow your nose and slice open an orange. Take a good whiff and see if it doesn't smell stronger then usual.

Answer 4

It might be because they have to winterize diesel fuel with anti-gelling agents for use in non-summer months. It may also depend on the manufacturer of the diesel and how up to date it is technically.

Answer 5

it may be because in the summer there are more of other smells around, also in the winter the air tends to be more poullution free