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~"' CONVENTION ON LONG-RANGE

TRANSBOUNDARY AIR POLLUTION

UN/ECE INTERNATIONAL CO-OPERATIVE PROGRAMME ON EFFECTS ON MATERIALS, INCLUDING HISTORIC AND CULTURAL MONUMENTS

Report No. 20:

ENVIRONMENTAL DATA REPORT SEPTEMBER 1993 TO AUGUST 1994

APRIL 1996

PREPARED BY THE ENVIRONMENTAL SUB-CENTRE

I + I NORWEGIAN INSTITUTE FOR AIR RESEARCH

LILLESTRØM/NORWAY

RE FERE NCE : 0-8208

DATE APRIL 1996

ISBN 82-425-0764-3

International Co-operative

Programme on Effects on Materials, including Historic and Cultural

Monuments

Environmental data report September 1993 to August 1994

Jan F. Henriksen, Kari Arnesen and Arild Rode

Prepared by the Environmental Sub-Centre

Norwegian Institute for Air Research

P.O. Box 100, N-2001 Kjeller, Norway

Contents

Page

1. Introduction 3

2. The measuring programme 4

3. Data from the monitoring test sites 4

4. Monthly mean concentrations 5

4.1. Gases, temperatures and relative humidity 5

4.2. Precipitation components 5

4.3. TOW and sunshine hours 5

5. Yearly mean concentrations 6

5 .1. Yearly mean values 6

5.2. TOW, sunshine hours and amount of precipitation 6

6. Calculations of monthly values 6

7. Results and discussions 8

8. Characterization of the air quality data 8

9. References 9

Tables and Figures 11

Appendix A Environmental data for the seventh year monthly

and yearly values 25

NILU OR 23/96

International Co-operative Programme on Effects on Materials, including Historic and Cultural

Monuments

Environmental data report September 1993 to August 1994

1. Introduction

Airborne acidifying pollutants are known to be one major cause of corrosion of different materials including the extensive damage that has been observed on historic and cultural monuments. In order to fill some important gaps of know- ledge in this field the Executive Body for the Convention on Long-range Transboundary Air Pollution decided to launch an international co-operative programme. The programme started in September 1987 and involves exposure at 39 test sites in 12 European countries and in the United States and Canada.

The aim of the programme is to perform a quantitative evaluation of the effect of sulphur pollutants in combination with NOx and other pollutants as well as climatic parameters on the atmospheric corrosion of important materials. For this purpose measurements of gaseous pollutants, precipitation and climate parameters have been initiated at or nearby each test site, together with evaluation of corro- sion of the exposed test materials at each site.

A Task Force is organizing the programme with Sweden as lead country and the Swedish Corrosion Institute serving as the Main Research Centre. Sub-centres in different countries have been appointed, each responsible for their own materials group. The materials groups are:

Structural metals, including steel, weathering steel, zinc and aluminium (Sub- centre responsible for evaluation: Company for Corrosion Protection and Surface Treatment, Prague, Czech Republic), copper and cast bronze (Bayerisches Landesamt flir Denkmalpflege, Munich, Germany).

Stone materials, including Portland limestone and White Mansfield dolomitic sandstone (Building Research Establishment, Department of Environment, Watford, United Kingdom).

Paint coatings, including coil coated steel with alkyd melamine,steel with alkyd paint, wood with alkyd paint system and wood with primer and acrylate (Norwegian Institute for Air Research, Lillestrøm, Norway).

Electric contact materials, including nickel, copper, silver and tin as coupons;

Eurocard connectors of different performance classes (Swedish Corrosion

Institute and Royal Institute of Technology, Stockholm, Sweden).

Environmental data storing, reporting and evaluation are the responsibility of the Norwegian Institute for Air Research. The aim of this report is to present all envi- ronmental data available from the seventh year of exposure, September 1993 to August 1994.

The yearly values for all test-sites for all seven years are included in this report.

To illustrate the quality of the data reported a statistical treatment of some of the environmental data was performed in the environmental report no. 9 (Henriksen et

al., 1992). In this report only few conclusions are drawn. A more complete

evaluation of the data will take place when the eight year's and final data sets are

reported. ,.

2. The measuring programme

The measuring programme includes a normal programme and an extended pro- gramme.

The measuring programme.

Components to be measured

Normal Gas S02, N02

programme Precipitation mm, pH, S0 ₄ -S, N03-N, c1-, conductivity Climate Temperature, relative humidity, time of

wetness (TOW) and sunshine hours

Extended Gas 03

programme Precipitation NH ₄ -N, Na, Ca, Mg, K

The data are to be reported to the environmental sub-centre as daily, weekly or monthly mean values, except for TOW, sunshine hours and mm precipitation which are reported as the sums. The data will be presented as monthly and yearly values.

3. Data from the monitoring test sites

The data are sent to the environmental sub-centre on special reporting forms.

Some sites have given the results in ASCII files on diskette.

All data presented by the environmental sub-centre, as in this report, are given with the same accuracy as in the filled-in reporting forms. For data series which include values "below the detection limit", these are, by convention, replaced with one half of the reported detection limits when calculating the mean values.

The monthly mean values are calculated from the daily or weekly values or used directly if monthly values are the only reported. Information about the data sets used for calculation of the mean values reported in this report is given by letter code

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D = daily records W = weekly records M = monthly records.

Information about the original measuring system for each test site is given the report "Description of test sites".

4. Monthly mean concentrations

The monthly and yearly values are given in the tables in Annex A. The data have been subject to the following restrictions and classifications:

4.1. Gases, temperatures and relative humidity

For monthly mean values calculated from daily measurements, the percentage of data used in the calculations is listed together with mean values.

A monthly mean value with more than 75% data for a given component is accepted without any remarks.

A monthly mean value for a component with between 50% and 75% of avail- able data has been marked with an asterisk.

A monthly mean value with less than 50% data is reported with an (X).

Monthly values with less than 50% of the data included in the calculations are not recommended used for statistical dose-response treatment.

4.2. Precipitation components

For monthly mean values calculated from daily or weekly rain results, the percentages of the total amount of rain used in the calculations are listed to- gether with the mean values.

A monthly mean value for a component with more than 75% of the amount of rain used in the calculations is accepted without any remarks.

A monthly mean value for a component with between 50% and 75% of the amount of rain used in the calculations has been marked with an asterisk.

A monthly mean value with less than 50% of the amount of rain used in the calculations is reported with an (X). Monthly values with less than 50% of the total rain included in the calculations are not recommended used for further data treatment.

4.3. TOW and sunshine hours

The total sum from the recorded days is adjusted to a complete month by dividing the sum with the numbers of records and multiply with the number of days in the month. The percentage of data used for these adjustment is listed together with the monthly value.

With more than 75% of the values reported, the monthly value will be reported without any remarks.

With between 50% and 75% of the values reported, the monthly value will be

reported with an asterisk.

With less than 50% of the values reported, a monthly value is reported with an (X). For further data treatment these data are often replaced by estimated values, see chapter 5.

5. Yearly mean concentrations

5.1. Yearly mean values

All values given for yearly mean values are treated in the same way as the monthly values. If daily results are reported during the whole year, all available daily values are used for the calculation of the mean value. The percentage of available data is also calculated and listed together with the yearly values in the tables in Annex A.

A yearly mean value for observations including 75% of the monthly values is accepted without any remarks. A yearly mean value including between 50%

and 75% of the monthly values is accepted with an asterisk.

A yearly mean value including less than 50% is reported with an (X).

If weekly or monthly values are reported, the monthly values are used in the cal- culations and the percentage is not listed.

5.2. TOW, sunshine hours and amount of precipitation

TOW, sunshine hours and amount of precipitation are reported as the total sum and must be completed to a full year if the results shall be of any use. Since there are seasonal variations in the climatic factors the use of average values for adjusting the results can be incorrect. To complete the yearly results estimated values were used. The estimated values were formed by comparing similar sites, by looking at reported values for other months from the same season or from meteorologic statistics. Only 4 estimated values are accepted for each parameter, and the estimated values are marked with a plus ( + ). If monthly values are available from the previous years, the missing monthly value is substituted with the mean value from the same month for the available years and marked with a (+).

If more than 4 of the monthly values are missing no yearly value is reported.

6. Calculations of monthly values

i

I/z;

Mean temperature (TM) TM = - ^{0 -}

---~--~~~---~ l

Ti = measured values i = number of records

Mean relative humidity (RHM)

i

LRH;

RHM=-0~_

l

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Time of wetness (TOW) (for incomplete data sets see chapter 4.3 and 5.2)

Sunshine hours (sh) (for incomplete data sets see chapter 4.3 and 5.2)

j

TOW=~. TOW _L.J

L I

0

j

sh= L ^sh;

0

Sunshine hours shall report the number of hours where the test panels have been exposed to sunlight. So far no efforts have been made to transform different sun radiation measurements to sunshine hours.

Mean gas concentrations GM

LG; i

G =-o __

M .

l

For some sites where complete information of the sampling period exists, another equation is used

n; = sampling period

Precipitation (for incomplete data sets see chapter 4.3 and 5.2)

i

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0

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f ^{[mm;· (lo-pH;)]}

pHM =+log- ^{0 ~-,- . ----} Imm;

0

weighted mean values for cations, anions and conductivity (CM)

M i

Imm;

0

7. Results and discussions

A list with site numbers, names and description of locations is given in Table 1.

The yearly results for the first, second, third, fourth, fifth, sixth and seventh year, are given in Table 2 and the monthly and yearly results from September 1993 to August 1994 in Annex A. The regularity of the environmental data is comparable to the previous years for most of the participants.UK and Estonia have not reported environmental data for the seventh year. Canada has also reported very minor amounts of data. There are some gaps in the data base for several countries and some question marks have been raised to some of the data reported. For that reason the TOW data from the Czech Republic are not listed in this report, but they will be reported together with the eight year's results later.

For calculating dose-response equation it is crucial to have complete data sets and sufficient spread in the values for the most important parameters. If gaps in the data occur, estimated values must sometimes be generated. To illustrate the quality of the data measured and their yearly fluctuation, scatter plots of the most important parameters are made.

The pattern of the seventh year results is similar to them of the previous years. In Figures 1-4 scatter plots of NO _2, SO _2, TOW and pH for the sixth versus the seventh year results are presented. The figures show that the environmental condition at the sites do not change too much from one year to the next. The trend with reduced yearly concentrations of SO ₂ through the years of the project is not so obvious for the seventh year as for the previous ones. For the rest of the parameters plotted, the results were clustered around a y=x line.

When the ECE programme started it was important to find test sites with different concentrations of SO _2, NO ₂ and H+ (pH). The figures show that we still are reasonably successful with the sites selected. The yearly mean concentrations for SO 2 has dropped and the total range goes now from 1 ug/rnr to 50 ug/ms with the majority of sites reporting values below 30 ug/ms. For NO ₂ the distribution is comparable with the fifth year results. The yearly mean concentrations are now ranging from 4 to 60 ug/ms plus one site (Milan) with a little less than 90 ug/m>.

The pH was between 4.0 and 6.5 and TOW between 1 100 and 6 000 hours per year. Many of the test sites closer to the Atlantic ocean are more or less affected by marine aerosols contribution. This is particularly the case for the sites in the United Kingdom, Lisbon, two Norwegian sites and the sites in the Netherlands. In addition high chloride concentrations are observed at the Italian and Spanish sites.

----~-\-:;f½Hef'-91f>:1'P.-:rizatiøfH:)f the air quality-d~---

In report no. 9 Environmental data report September 1989 to August 1990 (Henriksen et al., 1992) an extensive statistical evaluation of the results for gas concentrations was carried out. The main conclusions drawn in this report are still valid and can be summarized as follows:

NILU OR 23/96

Mean, median and 90-percentile characteristics of the annual data series for each test site were in most cases in good agreement, however, for some sites where the data have a distribution that is far from symmetry, their differences may be sub- stantial.

Little difference in the distribution of daily concentrations was found between the three yearly series by cumulative frequency plots. Most of the observed differ- ences were due to unequal patterns of missing data. This indicates good quality of the daily reported data.

The three-year and one-year series of gaseous compounds were found to mostly obey log-normal law of distribution, however, the data did not fit either normal or log-normal distribution in more cases than what would be expected by chance. It may therefore be necessary to establish other models. It is reasonable to assume that the deviations from the distribution are to some extent due to seasonal vari- ations, but this hypothesis was not tested.

When calculating annual means of concentrations, the seasonal differences are of most importance; therefore it may be reasonable to construct a rule based on sea- sonal availability of the data rather than on annual availability. Missing of two months in a season may probably be acceptable. However, four months of missing data will give a biased mean value.

When calculating monthly means, the rules for accepting the mean based on amount of available data were found reasonable. However, if we exclude daily data for calculation of annual means for other reasons than erroneous results, we are loosing information. We therefore recommend to use all available daily values for annual mean calculations, even if the daily data reported in a month is below 50%.

9. References

Henriksen, J.F., Arnesen, K. and Rode, A. (1991) Environmental data report, September 1987 to August 1989. Lillestrøm, Norwegian Institute for Air Research (UNÆCE International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments. Report No. 3).

Henriksen, J.F., Bartonova, A., Arnesen, K. and Rode, A. (1992) Environmental data report, September 1989 to August 1990. Lillestrøm, Norwegian Institute for Air Research (UNÆCE International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments. Report No. 9) (NILU OR 7/92).

Henriksen, J.F., Bartonova, A., Arnesen, K. and Rode, A. (1992) Environmental

data report, September 1990 to August 1991. Lillestrøm, Norwegian Institute

for Air Research (UNÆCE International Co-operative Programme on Effects

on Materials, including Historic and Cultural Monuments. Report No. 10)

(NILU OR 96/92).

The Swedish Corrosion Institute (1989) Description of test sites. Stockholm (UNÆCE International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments. Report No. 2).

Henriksen, J.F., Arnesen, K. and Rode, A. (1993) Environmental data report, September 1991 to August 1992. Lillestrøm, Norwegian Institute for Air Research (UNÆCE International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments. Report No. 16) (NILU OR 61/93).

Henriksen, J.F., Arnesen, K. and Rode, A. (1995) Environmental data report, September 1992 to August 1993. Kjeller, Norwegian Institute for Air Research (UNÆCE International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments. Report No. 17)

(NILU OR 21/95).

NILU OR 23/96

Tables and Figures

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Table 1: List of test sites and starting dates of exposure programme.

Test site Test site name Country Location

no.

1 Prague-Letnany The Czech Republic Urban

2 Kasperske Hory " Rural

3 Kopisty " Industry

4 Espoo Finland Urban

5 Åhtåri _" Rural

6 Helsinki-Vallila " Industry

7 Waldhof-Langenbrugge Federal Republic of Germany Rural

8 Aschaffenburg " Urban

9 Langenfeld-Reusrath " Rural

10 Bottrop ^" Industry

11 Essen-Leithe " Rural

12 Garmisch-Partenkirchen " Rural

13 Rome Italy Urban

14 Casaccia " Rural

15 Milan " Urban

16 Venice " Urban

17 Vlaardingen Netherlands Industry

18 Eibergen ^" Rural

19 Vredepeel " Rural

20 Wijnandsrade " Rural

21 Oslo Norway Urban

22 Borregaard " Industry

23 Birkenes " Rural

24 Stockholm South Sweden Urban

25 Stockholm Centre " Urban

26 Aspvreten " Rural

27 Lincoln Cathedral United Kingdom Urban

28 Wells Cathedral " Urban

29 Clatteringshaws Loch " Rural

30 Stoke Orchard " Rural, industry

31 Madrid Spain Urban

32 Bilbao " Industry

33 Toledo " Rural

34 Moscow Russia Urban

35 Lahemaa Estonia Rural

36 Lisbon-Jeronimo Monastery Portugal Urban

37 Dorset Canada Rural

38 Research Triangle Park USA (NC) Rural

39 Steubenville USA (Oh) Industry

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