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International Co-operation to Reduce Air Pollution

Introduction

Acid rain, or acid deposition as it should be correctly termed, is one of the major environmental issues of our time. Acid rain however, is not a new problem. In the mid 19th century, a Scottish scientist, Robert Angus Smith, began to study the effects of air pollution in Manchester where he coined the term "acid rain" to describe his findings. In Smith's time, acid rain fell in both towns and cities and downwind from them but now, following Clean Air Acts, levels of smoke and sulphur dioxide have been greatly reduced. Gaseous and particulate airborne pollutants are now dispersed higher into the atmosphere via tall chimney stacks. Other sources of pollutants such as vehicle exhausts may also be transported high into the atmosphere, depending on weather conditions.

Complex chemical reactions occur over time in the atmosphere including the formation of sulphuric and nitric acids, leading to the deposition of acidic precipitation. Because pollutants can be carried many hundreds of kilometres by winds, acid pollutants emitted in one country may be deposited as acid precipitation in other countries. Acid deposition has become an international problem. This problem is highlighted by the fact that emission of a particular pollutant from one country does not equal the deposition of that pollutant in the same country. Some countries emit small quantities of pollutants yet deposition can be several times greater, for example Norway, Sweden, Austria and Switzerland. Other countries such as Bulgaria, Italy and the UK emit more pollution than is deposited in their country because of prevailing wind directions.

Within Europe, emissions of air pollutants vary greatly, depending upon many factors such as size of population, degree of industrialisation, pollution control equipment used, agricultural practices, number of vehicles and political attitudes on environmental issues. The tables below show emissions (and deposition) of sulphur and nitrogen.

Estimated emissions and deposition of sulphur and nitrogen for European countries: 1990 and 1998

Country

Sulphur emissions ('000 tonnes per year)

Sulphur deposition
('000 tonnes per year)
1998

Nitrogen emissions ('000 tonnes per year)

Nitrogen deposition
('000 tonnes per year)
1998

1990

1998

From own country

Total deposition

1990

1998

From own country

Total deposition

Albania

[36]

[36]

5

35

[7]

[7]

0.5

15

Armenia

36

1.5

0.5

16

14

3

0.5

7

Austria

45

23

5.5

69

59

52

7

50

Belarus

318

95

32

191

87

50

8

73

Belgium

186

101

18

54

103

92

9

39

Bosnia & Herz.

240

[20]

50

106

[24]

[24]

3

31

Bulgaria

1004

625

128

218

110

68

18

51

Croatia

90

45

8

68

27

23

2

35

Cyprus

23

25

2

5

5

7

0.5

3

Czech Rep.

938

221

45

143

226

126

15

65

Denmark

91

38

6

75

85

70

3

57

Estonia

126

55

5

27

21

14

0.5

14

Finland

130

45

20

121

105

77

19

66

France

634

418

165

389

571

502

172

369

Georgia

124

163

 

 

36

173

 

 

Germanyb

2660

646

201

452

824

541

157

365

Greece

251

270

67

183

99

116

23

62

Hungary

505

295

61

150

72

66

17

62

Iceland

12

13

2

11

8

9

1

7

Ireland

93

88

31

52

36

37

4

22

Italy

825

5102

123

363

589

5123

137

244

Latvia

60

20

5

46

28

13

1

26

Lithuania

111

47

11

64

48

18

1.5

31

Luxembourg

7

2

0.1

3

7

5

0.2

3

FYRMacedonia

8

83

 

 

2

23

 

 

Moldova

132

16

 

 

30

7

 

 

Netherlands

101

57

14

60

176

134

14

48

Norway

26

15

5

100

67

68

8

56

Poland

1605

948

364

645

389

301

84

240

Portugal

171

1672

32

58

93

114

24

50

Romania

655

4561

179

389

166

97

31

103

Russian Federa

2230

1104

689

1662

1094

756

352

766

Slovak Rep.

271

90

15

91

68

40

5

36

Slovenia

98

61

8

26

19

19

1.5

16

Spain

1025

7492

229

319

351

3632

127

231

Sweden

60

25

10

143

103

78

18

107

Switzerland

21

19

4

30

50

37

6

29

Turkey

416

644

298

587

204

259

100

254

Ukraine

1391

5663

210

574

333

1383

33

189

UK

1868

807

249

328

848

533

101

170

Yugoslavia

254

260

75

184

20

20

4

44

Reducing European Emissions

Sulphur Dioxide

In the late 1970s, the United Nations Economic Commission for Europe (UNECE) set up an international convention concerning Long Range Transboundary Pollution. In 1984 and 1985 most UNECE members agreed to reduce sulphur dioxide emissions by 30% (on 1980 levels) by 1993. This was called the 30% club. All of the countries that signed the Protocol achieved this reduction, and many of those that did not sign, have met these reductions. Austria greatly exceeded their target reduction by achieving an 82% reduction, whilst the UK achieved a 35% reduction. Only two countries increased their emissions, Croatia (20%) and Greece (27%).

In June 1994, a number of European countries signed the second Protocol for sulphur. Most of the western European countries have agreed to reduce sulphur emissions by between 70 and 80% by the year 2000 (against 1980 levels) whilst eastern European countries generally have a lower target of between 40 and 50% (against 1980 levels).

Overall, emissions of sulphur dioxide in Europe are estimated to have fallen by 25-30% between 1980 and 1990 (compared with 75% in the UK). If the signatories of the 1994 Protocol achieve their target reductions, European sulphur dioxide emissions are estimated to fall 47% by 2005 and 51% by 2010 (on 1980 levels).

Nitrogen Dioxide

The Sofia Protocol for reducing nitrogen oxide emissions was set up in 1988. This required all countries that signed the Protocol to stabilise emissions of NOx (against 1987 levels) but some countries committed themselves to 30% reductions by 1998 (against levels of any year between 1980 and 1986). However, many of these countries are unlikely to meet these targets; several countries such as Spain and Italy have increased their NOx emissions between 1987 and 1993 by 41% and 8% respectively.

Targets for Combustion Plants

In 1988 a Directive was introduced for EC countries which requires Large Combustion Plants over 50MW in size to reduce emissions of SO2 and NOx by varying percentages by 1998 and 2003 (against 1980 levels). For the UK, reductions of 60% SO2 by 2003 and 30% NOx by 1998 have been set. The UK is well on course to exceed both targets through new gas-fired power stations (which produce small quantities of SO2 and NOx) replacing coal fired power stations, and flue gas desulphurisation equipment fitted to Drax and Ratcliffe-on-Soar power stations.

Vehicle Emissions

In addition, all cars sold within the European union from 1993 onwards have to be fitted with a catalytic converter to help reduce emissions of vehicular pollutants. Many non-EU countries also require catalytic converters to be fitted to vehicles sold within their countries.

Gothenburg Protocol

The most recent UNECE Convention on Long Range Transboundary Air Pollution protocol was signed by 27 countries in December 1999. The Gothenburg Protocol, designed to Abate Acidification, Eutrophication and Ground-level Ozone aims to cut emissions of four pollutants: sulphur dioxide (SO2), nitrogen oxides (NOx), volatile organic compounds (VOCs), and ammonia (NH3), by setting country-by-country emission ceilings to be achieved by the year 2010. The table below lists the countries that have agreed to sign the 1999 Protocol and the expected emissions reductions by 2010.

Country

SO2 1980-2010

SO2 1990-2010

NOx 1980-2010

NOx 1990-2010

VOCs 1980-2010

VOCs 1990-2010

Ammonia 1980-2010

Ammonia 1990-2010

EU member countries that have signed*

85%

75%

49%

50%

53%

56%

16%

15%

Non-EU** countries that have signed

61%

49%

15%

31%

22%

28%

 22%

 20%

Europe (both of the above)

73%

61%

36%

42%

41%

44%

20%

18%

Conclusion

Although SO2 emissions in Europe have been falling steadily over recent years, NOx emissions rose during the 1980s and have only recently begun to fall at a slower rate than was anticipated. Acid rain will therefore continue to be a problem in Europe until these emissions can be dramatically reduced.