The given line graph describes the amount of polluted air emitted in the UK, measured in millions of tonnes from three sources: industry, transport and households between 1900 and 2005.
Overall, downward trends were observed in most categories, especially the air from industry, whereas the air pollutants from the transport experienced an increase. Recording the highest figure in most time, industry remained the dominant amount of emissions, while households represented the smallest figure throughout the period.
Regarding the decreasing categories, industry accounted for the highest amount of air pollutants in the beginning of the period at just under 6 million tonnes, prior to declining to exactly 5 million tonnes in 1993. This was followed by a significant drop in the following years, before converging with transport at around 2.5 million tonnes in 2002. Subsequently, the amount of emissions from industry continuously decreased and finished at precisely 2 million tonnes in 2005. Furthermore, the quantity of air pollutants from households remained stable at a million until 1999, before experiencing a more substantial decline to roughly zero in 2005. Lastly, both the decrease in the amount of emissions from industry and households contributed to the overall decline in total emissions from approximately 8 to 5 million tonnes in 2005.
Concerning the increasing category, transport represented a similar level with households at a million tonnes in 1900, before rising to about 1.5 million tonnes in 1993. However, it recorded a small drop in 1996 to its initial point, before remaining at this level until 1999. Lastly, it experienced a significant growth and surpassed industry at around 2.5 million tonnes in 2002, prior to continuously increasing by 0.5 million tonnes until the end.