Emissions of acidifying gases and ozone precursors, 1990-2011, final figures

The new estimations for 2011 are now available for nitrogen oxides (NO _X ), sulphur dioxide (SO ₂ ), ammonia (NH ₃ ), non-methane volatile organic carbon (NMVOC) and carbon monoxide (CO). The new estimations confirm previous trends, but there are significant changes in emission levels, particularly concerning ammonia.

According to the Gothenburg Protocol, ammonia emissions are not to exceed 23 000 tonnes per year. Previous estimations were just below this level. In 2012, adjustments were made to the estimates of emissions from agriculture (see box below), and this resulted in an upward shift in estimated emissions from agriculture, ranging from 6 to 24 per cent in the time series 1990-2011. In 2011, NH ₃ emissions totalled 26 200 tonnes, which is 14 per cent above the ceiling level. Agriculture is the source of 91 per cent of the ammonia emissions in Norway.

Reduced emissions of NO _X from transport

The total emission of NO _X has been reduced by 8 per cent since 1990. Transport emission is down as much as 26 per cent, with road traffic contributing the most to this reduction. Emissions from coastal navigation have been reduced by almost 20 per cent since 2008. This is partly due to measures implemented by the NO _X Fund, which is financed by industry and businesses. Energy use in coastal navigation has not had the same decrease.

Road traffic was the source of 21 per cent of total NO _X emissions in 2011. Other transport, including navigation, aviation and motorized equipment, was responsible for 36 per cent of the emissions, while oil and gas extraction constituted 29 per cent of total NO _X emissions.

Reduced SO ₂ emissions from manufacturing and transport

The SO ₂ emissions in Norway have been reduced by 64 per cent since 1990, with a 66 per cent reduction in emissions from manufacturing. This has been achieved by pollution control, the closure of pollution-generating businesses and a reduced consumption of petroleum products. The total reduction from transport is 70 per cent from 1990, which is mainly due to less sulphur in the fuels. Most of the reduction took place at the beginning of the period.

Manufacturing and mining are still the largest sources of emissions, and together constituted 67 per cent of total emissions in 2011. Transport was responsible for 17 per cent of the SO ₂ emissions.

NMVOC emissions greatly reduced

The emissions of NMVOC have been more than halved since 1990, and since the peak in 2001, emissions are down by two thirds. Loading of crude oil offshore was the main reason for the increase in emissions from 1990 to 2001. Measures to prevent these emissions have resulted in a decrease of 90 per cent from 2001 to 2011. Total emissions are now well below the target level in the Gothenburg Protocol.

Acidifying emissions are down

Emission of gases that transform into acid can be expressed in terms of acid equivalents . Total emissions of the three gases NO _X , SO ₂ and NH ₃ measured as acid equivalents have been reduced by 17 per cent since 1990. SO ₂ and NO _X emissions are down 64 and 8 per cent respectively, while NH  emissions have increased by 8 per cent. In 2011, NOx  constituted 65 per cent of the acidifying emissions, while NH ₃ and SO ₂ were responsible for 25 and 10 per cent of these emissions respectively.