Conditions Ideal for Ozone This summer, with its very hot and generally dry weather and stagnant air, has been ideal for the creation of low-level ozone.

Not incidentally, the researchers calculate, these reductions in low-level ozone and black carbon would yield lots of benefits long before 2050.

The most important ones are carbon dioxide, methane, CFCs and low-level ozone.

Huge clouds of low-level ozone have formed over central Brazil and the Atlantic, apparently as a result of burning forest and savannah grasslands.

They will monitor concentrations of nitrogen oxides, sulphur dioxide, carbon monoxide and low-level ozone, as well as airborne fine dust and hydrocarbons such as benzene.

On March 10 the authorities issued a warning to people to stay indoors after concentrations of low-level ozone reached record levels.

Government monitoring stations measure levels of pollutants such as nitrogen oxides or low-level ozone but fail to publicise them widely.

One of the by-products of these fragrance lamps is low-level ozone, which has been attributed to the "purification process" of the lamps in eliminating odor.

Unburned hydrocarbons, lost to the atmosphere through evaporation, are considered among the important contributors to the formation of low-level ozone in urban air.

Increased temperatures and sunny days help lead to the formation of low-level ozone from volatile organic compounds and nitrous oxides which already exist in the air.