Скачать презентацию Hyytiälä 2005 Air Ion Research in Atmospheric Electricity Скачать презентацию Hyytiälä 2005 Air Ion Research in Atmospheric Electricity

4c67e1d490e1626cf6263b3f9925c084.ppt

  • Количество слайдов: 28

Hyytiälä 2005 Air Ion Research in Atmospheric Electricity Hannes. Tammet@ut. ee Institute of Environmental Hyytiälä 2005 Air Ion Research in Atmospheric Electricity Hannes. [email protected] ee Institute of Environmental Physics, University of Tartu

Hyytiälä 2005 CONTENTS: • Discovery and Nature of Air Ions • Air Ion Measurements Hyytiälä 2005 CONTENTS: • Discovery and Nature of Air Ions • Air Ion Measurements Until 1963 • World Data Centre • Dataset ATMEL 1 • Air Ion Measurements at Tahkuse

Discovery and Nature of Air Ions Air electrical conductivity: Hyytiälä 2005 Richmann 1744 Coulomb Discovery and Nature of Air Ions Air electrical conductivity: Hyytiälä 2005 Richmann 1744 Coulomb 1785 1834: William Whewell. Letter to Michael Faraday 5 May: . . . For the two together you might use the term ions. 1834: Michael Faraday. Philosophical Transactions of the Royal Society. CXXIV. 79: . . Finally, I require a term to express those bodies which can pass to the electrodes … I shall call them ions. Greek ion, something that goes, neuter present participle of ienai, to go. Thomson, J. J. (1898) Discharge of Electricity Through Gases, Westminster. Nobel Prizes: Thomson Rutherford Lenard Wilson Hess 1906 1908 1905 1927 1936

Discovery and Nature of Air Ions Hyytiälä 2005 Elster, J. , Geitel, H. (1899) Discovery and Nature of Air Ions Hyytiälä 2005 Elster, J. , Geitel, H. (1899) Über die Existenz elektrischer Ionen in der Atmosphäre. Terr. Magn. Atmos. Electr. 4, 213 -234. (Terrestrial Magnetism was grounded 1996, renamed to Terrestrial Magnetism and Atmospheric Electricity 1899 and to Journal of Geophysical Research 1949) 3. 8 d 3 min 27 min 20 min <1 ms 23 y 5 d 138 d 222 Rn → 218 Po → 214 Pb → 214 Bi → 214 Po → 210 Pb → 210 Bi → 210 Po → 206 Pb 5. 5 Me. V 5. 2 Mev 7. 7 Me. V 5. 3 Me. V 56 s 0. 2 s 1 h 183 s 220 Rn → 216 Po → 212 Bi → 208 Tl → 208 Pb 6. 3 Me. V 6. 8 Me. V 6 Me. V Langevin, P. (1905) Sur les ions de l’atmosphère. C. R. Acad. Sci. 140, 232 -234. Pollock, J. A. (1915) A new type of ion in the air. Phil. Mag. 29, 636 -646. . . . Israël, H. (1970) Atmospheric Electricity. Jerusalem.

Expanding research fields and the position of air ions as a common research subject Expanding research fields and the position of air ions as a common research subject AS – Aerosol Science GD AIR IONS GD – Gas Discharge and Plasma Physics AS AE AE – Atmospheric Electricity Hyytiälä 2005

Air Ion Measurements Until 1963 Hyytiälä 2005 Measured quantities: Air conductivity Concentration of small Air Ion Measurements Until 1963 Hyytiälä 2005 Measured quantities: Air conductivity Concentration of small air ions } Mobility and size of small air ions Concentrations of few ion groups Mobility distribution of air ions During the first period of the increased activity in 1904. . . 1914, air conductivity was routinely measured at a large number of stations. Both conductivity and small ion concentration were systematically measured at about 10 locations in Europe and South America. The original data of old measurements are often lost or stored in archives inaccessible for the wide community of scientists. A large amount of work in recovering and analysing retrospective data has been done by Giles Harrison in Reading, UK.

Analysis of retrospective data by Harrison: Hyytiälä 2005 F. Märcz and R. G. Harrison Analysis of retrospective data by Harrison: Hyytiälä 2005 F. Märcz and R. G. Harrison (2005) Further signatures of long-term changes in atmospheric electrical parameters observed in Europe. Annales Geophysicae 23. Harrison R. G. and Ingram W. J. (2004) Air-earth current measurements at Kew, London, 1909 -1979. Atmos. Res. , doi: 10. 1016. Harrison, R. G. (2004) Long-range correlations in measurements of the global atmospheric electric circuit. J. Atmos. Solar. Terr. Phys. , 66, 1127 -1133. Harrison R. G. (2004) Long term measurements of the global atmospheric electric circuit at Eskdalemuir, Scotland, 19111981. Atmos. Res. 70 (1), 1 -19. Harrison R. G. and Aplin K. L. (2003) Nineteenth century Parisian smoke variations inferred from Eiffel Tower atmospheric electrical observations. Atmos. Environ. 37, 5319 -5324. Märcz F. and Harrison R. G. (2003) Long-term changes in atmospheric electrical parameters observed at Nagycenk (Hungary) and the UK Observatories at Eskdalemuir and Kew. Annales Geophysicae 21, 2193 -2200. Harrison R. G. (2003) Twentieth century atmospheric electrical measurements at the observatories of Kew, Eskdalemuir and Lerwick. Weather 58, 11 -19. Harrison R. G. (2002) Twentieth century secular decrease in the atmospheric electric circuit. Geophysical Research Letters, 29(14) DOI 10. 1029/2002 GL 014878, Harrison R. G. and Aplin K. L. (2002) Mid-nineteenth century diurnal smoke concentrations at Kew, London. Atmos. Environ. 36, 25 4037 -4043. Harrison R. G. (2004) Twentieth century air pollution near London: a reconstruction from measurements of atmospheric electricity. Childhood Leukaemia: Incidence, causal mechanisms and prevention, London 6 th-10 th September 2004, 4 -6. Harrison R. G. (2003) Climate change and long-term variations in the atmospheric electrical system. Proc. 12 th International Conference on Atmospheric Electricity, Versailles, vol 2, 703 -706, 2003. Harrison R. G. (2003) Long-term changes in aerosol and the electrical conductivity of oceanic air. Proc. 14 th annual conference, The Aerosol Society, Reading, 2 nd-3 rd April 2003, 22 -25. Harrison R. G. and Aplin K. L. (2002) Aerosol variations inferred from historical atmospheric electrical data. Proc. XIIIth Annual Conference The Aerosol Society, Lancaster, April 2002, 113 -116.

Concentration of few ion groups Hyytiälä 2005 Early thirties: H. Israël and L. Schulz Concentration of few ion groups Hyytiälä 2005 Early thirties: H. Israël and L. Schulz (Ph. D. thesis 1933 “Beiträge zur Kenntnis der Luftionen”) initiated measurement of four ion groups (ultralarge, Langevin, large intermediate, small intermediate) in many locations in Europe. 4 -10 measurements were made in one location. The results are resumed in the book by Israël (1970). Systematic measurements were made by J. Reinet in Tartu during full year 1951. Events of increased concentration of intermediate ions (charged nanometer particles) were discovered. P. Prüller carried out 3 year measurements in Tartu 1960 -1963. The concentrations of ion groups were recorded 4 -8 times every day. Early fifties: Christian Junge showed that the measurements of large and intermediate ions contain unique information about atmospheric aerosol:

Mobility distribution of air ions Hyytiälä 2005 First high resolution measurement of atmospheric ion Mobility distribution of air ions Hyytiälä 2005 First high resolution measurement of atmospheric ion mobility distribution: Yunker, E. A. (1940) The mobility spectrum of atmospheric ions. Terr. Magn. Atmos. Electr. 45, 127 -132. Episodic measurements have been performed since 1950 in Japan by Misaki, Sekigava, Suzuki, Kojima, Nagato, . . .

World Data Centre The World Data Centre for Atmospheric Electricity operated within the Main World Data Centre The World Data Centre for Atmospheric Electricity operated within the Main Geophysical Observatory, St. Petersburg, Russia 1965 -1993. The data for 1964 -1989 were published as monthly reports "Results of ground observations of atmospheric electricity". Kolokolov, V. P. (1981) On activity of World Data Centre for Atmospheric Electricity (in Russian). Meteorologya i Gidrologya, N 2, 119 -120. Gordyuk, V. P. and Tammet, H. (1992) Modernization of the World Data Center for Atmospheric Electricity. Proc. 9 th Int. Conf. on Atmospheric Electricity, St. Petersburg, 1, pp. 46– 49. Dolezalek, H. (1992) The World Data Centre for Atmospheric Electricity and global change monitoring. European Science Notes Information Bulletin. 92 -02. Office of Naval Research, European Office, 1 -37. Hyytiälä 2005

List of 37 stations, which have been sent the data to WDC Hyytiälä 2005 List of 37 stations, which have been sent the data to WDC Hyytiälä 2005 Aachen (FRG) Kara-Dag (Ukraine) Porto (Portugal) Auckland (N-Zealand) Kew (UK) Potsdam (Germany) Athens (Greece) Kiev (Ukraine) Sacushima (Japan) B-Elan (Russia) Kirov (Russia) Soccoro (USA) Brest (France) Lisbon (Portugal) Swider (Poland) Budapest (Hungary) Lerwick (UK) Tashkent (Uzbekistan) Dourbes (Belgium) Macherata (Italy) Toronto (Canada) Eskdalemuir (UK) Memambetsu (Japan) Uccle (Belgium) Dusheti (Georgia) Montreal (Canada) University Park (USA) Helsinki (Finland) Murmansk (Russia) Venice (Italy) Irkutsk (Russia) Nivot Ridge (USA) Verkhnee Dubrovo (Russia) Kakioka (Japan) Odessa (Russia) Voeikovo (Russia) Yuzhno-Sakhalinsk (Russia)

A page of WDC monthly brochure Hyytiälä 2005 A page of WDC monthly brochure Hyytiälä 2005

A sample of original WDC data written in Ya. OD Hyytiälä 2005 599307096 599307096 A sample of original WDC data written in Ya. OD Hyytiälä 2005 599307096 599307096 599307096 599307096 599307096 4 4 4 4 4 1 9999999 110999999 111999999 112999999 113999999 114999999 115999999 116999999 117999999 118999999 119999999 120999999 121999999 122999999 123999999 124999999 2 1999999 2 2999999 2 3999999 8 7 7 7 5 4 6 6 6 5 3 4 3 5 5 6 7 796121200120150 29999 696999999999999999999 69610 084000100 39999 596999999999 496999999999 69610 084000 90 49999 596999999972 2 596999999972 1 59610 882020 90 472 1 596999999972 1 496999999972 1 596101088002 90 672 1 496999999972 1 596999999972 2 696101088002110 573 1 6969999999999999973 2 796101088220120 373 1

Dataset ATMEL 1 Hyytiälä 2005 Stations: 13 Quantities: 51 Variables: 158 Diurnal series: 456 Dataset ATMEL 1 Hyytiälä 2005 Stations: 13 Quantities: 51 Variables: 158 Diurnal series: 456 105 Data format: Diary (Data. Diurna) Bytes: 42 922 325 Latitude Longitude Altitude Station 59. 97 30. 3 72 Voeikovo near St. Petersburg (former Leningrad) 52. 27 104. 32 467 Irkutsk near Baikal See 42. 08 44. 7 910 Dusheti near Tbilisi 56. 8 60. 63 237 Verhnee Dubrovo near Jekaterinenburg (former Sverdlovsk) 46. 48 30. 63 42 Odessa 46. 95 142. 72 22 South-Sakhalinsk (Japanese name Toyohara) 41. 27 69. 27 477 Tashkent 47. 5 11. 15 1780 Wank Peak: R. Reiter's station near Garmish-Partenkirchen 59. 93 17. 58 10 Marsta Meteorological Observatory (University of Uppsala) 59. 436 24. 757 10 Viru: City centre of Tallinn (Estonia) 58. 55 26. 38 40 Saarejärve: EMEP station in Estonia 59. 53 25. 88 5 Lahemaa: EMEP station in Estonia 58. 39 21. 84 5 Vilsandi: EMEP station in Estonia

ATMEL 1 quantities Hyytiälä 2005 Type of quantity # Cloud characteristic Weather type Condensation ATMEL 1 quantities Hyytiälä 2005 Type of quantity # Cloud characteristic Weather type Condensation nuclei Concentrations of gases Humidity Electric field Electric current Air conductivity Concentration of small air ions Space charge Air pressure Optical radiation (incl. UV) Air temperature Richardson number Wind Visibility 8 3 3 6 2 3 2 1 1 4 6 1 5 1

ATMEL 1 quantities page 1: Hyytiälä 2005 Stat. Quantity From To Irk Ode Sakh ATMEL 1 quantities page 1: Hyytiälä 2005 Stat. Quantity From To Irk Ode Sakh Tash Ural Vo Wank Irk 19970331 19940831 19940630 19951231 19961210 19970331 19831231 19970331 Ode Sakh Tash Ural Vo Irk Ode Sakh 19890101 19890101 19890101 19890101 19890101 19940831 19940630 19951231 19961210 19970331 19940831 19940630 19951231 19961210 19970331 19940831 19940630 Cl-low Cl-low Cl-mid Cl-mid Cl-nim Cl-nim Cl-R Cl-str 19890101 19890101 19890101 19890101 19890101 19810613 19890101 Cl-str Cl-str Cl-tot Cl-tot Cl-upp Cl-upp Cl-ver

ATMEL 1 quantities page 2: Hyytiälä 2005 Stat. Quantity From To Tash Ural Vo ATMEL 1 quantities page 2: Hyytiälä 2005 Stat. Quantity From To Tash Ural Vo Dush Irk Ode Sakh Tash Ural Vo Wank Viru Wank Dush Irk Marsta Ode Sakh 19890101 19670101 19890101 19740101 19660101 19720801 19940725 19720801 19670101 19890101 19930203 19890101 19951231 19961210 19970331 19801231 19970331 19940831 19940630 19951231 19961231 19970331 19831231 19990731 19831231 19801231 19970331 19981203 19940831 19940630 Tash Ural Wank Vo Marsta Wank Dush Irk Marsta Ode Sakh Ural Wank Vo Dush Irk 19890101 19740101 19720801 19660101 19930205 19940531 19720801 19930204 19720801 19740103 19670101 19890101 19930204 19890101 19740101 19730724 19660103 19670101 19890101 19951224 19961210 19831231 19970331 19981203 19980923 19831231 19981130 19831231 19820704 19801231 19970331 19981130 19940831 19910815 19951001 19831130 19970331 19801231 19970331 Cl-ver C-MGO C-MGO CNR 1: cm-3 CNR 2: cm-3 CNR 3: cm-3 CO: mg/m 3 E: inv/h E: V/m E: V/m E: V/m Eflct: V/m H 2 O: g/kg j: p. A/m 2 jp: p. A/m 2 L-: f. S/m L-: f. S/m L+: f. S/m

ATMEL 1 quantities page 3: Hyytiälä 2005 Stat. Quantity From To Marsta Ode Sakh ATMEL 1 quantities page 3: Hyytiälä 2005 Stat. Quantity From To Marsta Ode Sakh Ural Wank Vo Wank Saare Vils Viru Saare Wank Vils Viru Lahe Saare 19930203 19890204 19890101 19740101 19730724 19660102 19720801 19971231 19950418 19940725 19971122 19740308 19950418 19940725 19940615 19971112 19981203 19940831 19910815 19951001 19831130 19970331 19831231 19990620 19990630 19990731 19990620 19830729 19990630 19990731 19990620 Vils Viru Marsta Dush Irk Ode Sakh Tash Ural Vo Wank Marsta Wank 19940528 19960605 19940531 19670101 19890101 19890101 19740101 19660101 19720801 19940531 19720801 19990630 19990731 19981130 19801231 19970331 19940831 19940630 19951231 19961231 19970331 19831231 19980923 19831231 L+: f. S/m NC-: cm-3 NC+: cm-3 NO: ug/m 3 NO 2: ug/m 3 NOX: ug/m 3 O 3: ug/m 3 p: mb Ph-code Ph-code Ph-int Ph-int Rad: W/m 2 RH%

ATMEL 1 quantities page 4: Hyytiälä 2005 Stat. Quantity From To Marsta Wank Saare ATMEL 1 quantities page 4: Hyytiälä 2005 Stat. Quantity From To Marsta Wank Saare Vils Viru Wank Marsta Wank Marsta Irk Lahe Marsta Ode 19940531 19930204 19730724 19770205 19971231 19940528 19940726 19730729 19720801 19940531 19730703 19740307 19940531 19890101 19970218 19940531 19890101 19981130 19831231 19990620 19990630 19990731 19831231 19981130 19831231 19981130 19970331 19990731 19981130 19940831 Sakh Tash Ural Wank Vils Vo Irk Lahe Ode Sakh Tash Ural Wank Vils Vo Marsta Wank 19890101 19720801 19951231 19890101 19970219 19890101 19720801 19951231 19890101 19940531 19750109 19940630 19951231 19961210 19831231 19960720 19970331 19990731 19940831 19940630 19951231 19961210 19831231 19960720 19970331 19981130 19831231 Ri SC: p. C/m 3 Sky: W/m 2 SO 2: ug/m 3 Sun% T: C T 08: C T 10: C Tepot: K Tgr: K/m Tpot: K UV: m. W/m 2 Wflct: m/s Wind: deg Wind: deg Wind: deg Wind: m/s Wind: m/s Wind: m/s Wind 08: m/s Wind 10: m/s Vis: km

Diary format Hyytiälä 2005 From data by Reinhold Reiter: WANK. 06. 12. 77 STUNDENWERTE: Diary format Hyytiälä 2005 From data by Reinhold Reiter: WANK. 06. 12. 77 STUNDENWERTE: T -00. 4 -01. 0 -02. 2 -02. 9 -01. 8 -01. 7 -00. 1 +00. 2 +00. 7 +00. 1 -00. 4 -00. 1 +00. 5 -00. 2 -00. 5 -01. 2 -02. 0 -02. 1 -02. 3 -02. 7 -02. 8 -03. 0 RF 21. 5 21. 8 24. 2 26. 2 22. 4 24. 0 20. 7 22. 8 29. 8 36. 1 41. 1 43. 8 45. 9 49. 4 47. 6 50. 6 52. 8 58. 6 61. 2 63. 7 76. 1 83. 8 88. 1 89. 5 Modified: 06. 12. 77, T(Wank), -0. 4, -1. 0, -2. 2, -2. 9, -1. 8, -1. 7, -0. 1, +0. 2, +0. 7, +0. 1, -0. 4, -0. 1, +0. 5, -0. 2, -0. 5, -1. 2, -2. 0, -2. 1, -2. 3, -2. 7, -2. 8, -3. 0 06. 12. 77, RF(Wank), 21. 5, 21. 8, 24. 2, 26. 2, 22. 4, 24. 0, 20. 7, 22. 8, 29. 8, 36. 1, 41. 1, 43. 8, 45. 9, 49. 4, 47. 6, 50. 6, 52. 8, 58. 6, 61. 2, 63. 7, 76. 1, 83. 8, 88. 1, 89. 5 Advantages of diary: • adapted for routine environmental measurements • saved as immediately readable text • data manager will be available as freeware

A diary standard: Data. Diurna Hyytiälä 2005 DDD, ATMEL 1, 20041230 19950615, Tash, Cl-mid, A diary standard: Data. Diurna Hyytiälä 2005 DDD, ATMEL 1, 20041230 19950615, Tash, Cl-mid, h 0, 1, 1, 1, 1, 0, 0, 0, 1, 1 19950615, Tash, Wind: deg, h 0, 87, 103, 120, 133, 147, 160, 203, 247, 290, 193, 97, 0, . . . 19950615, Tash, Wind: m/s, h 0, 1, 2, 2, 2, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1 19950615, Marsta, RH%, h 0, 100. 0, 99. 6, 98. 4, 98. 9, 98. 2, 94. 6, . . . 19950615, Marsta, E: V/m, h 0, 10, -2, 46, 72, 67, 66, -1, 164, 91, 61, 59, 98, 93, 76, 84, . . . 19950615, Marsta, L+: f. S/m, h 0, 23. 1, 22. 9, 23. 9, 24. 8, 24. 5, 24. 4, 24. 1, 24. 2, 24. 7, 25. 7, . . 19950615, Marsta, L-: f. S/m, h 0, 13. 3, 13. 8, 14. 0, 15. 7, 19. 5, 19. 1, 20. 0, 20. 6, 25. 2, 24. 5, . . . 19950615, Marsta, SC: p. C/m 3, h 0, 3. 7, 1. 3, -0. 5, 1. 8, -1. 0, -0. 6, -0. 3, 4. 3, 8. 2, . . 19950615, Marsta, j: p. A/m 2, h 0, 0. 36, -0. 07, 1. 74, 2. 92, 2. 95, 2. 87, -0. 04, 7. 35, 4. 54, 3. 06, . . 19950615, Viru, SO 2: ug/m 3, h 0, 3. 7, 2. 9, 2. 5, 2, 2. 6, 3. 8, 6. 1, 7. 5, 7. 7, 6. 7, 5. 2, 5, 2. 7, 2. 1, . . . 19950615, Vils, NO 2: ug/m 3, h 0, 4. 1, 4. 2, 4. 3, 3. 1, 4. 1, 9999, 0. 8, 2. 1, 9999, 1. 4, 3. 4, 1. 8, 0. 4, . . . 19950615, Vils, NOX: ug/m 3, h 0, 4. 3, 4. 5, 3. 5, 4. 5, 9999, 1. 1, 2. 5, 9999, 1. 8, 4. 3, 2. 2, 0. 6, . . .

A diary standard: Data. Diurna Hyytiälä 2005 DDS, ATMEL 1, 20041223 Vo, 59. 97, A diary standard: Data. Diurna Hyytiälä 2005 DDS, ATMEL 1, 20041223 Vo, 59. 97, 30. 3, 72, Voeikovo near St. Petersburg (former Leningrad) Irk, 52. 27, 104. 32, 467, Irkutsk near Baikal See Dush, 42. 08, 44. 7, 910, Dusheti near Tbilisi Ural, 56. 8, 60. 63, 237, Verhnee Dubrovo near Jekaterinenburg (former Sverdlovsk) Ode, 46. 48, 30. 63, 42, Odessa stationlabel, latitude, longitude, altitude[, explanations] DDQ, ATMEL 1, 20041223 T: C, Celsius, 1, -90, 99, Air temperature near the station T 08: C, Celsius, 2, -90, 99, Air temperature at height of 0. 8 m T 10: C, Celsius, 2, -90, 99, Air temperature at height of 10 m Tgr: K/m, 3, -2, 2, 9, Gradient of temperature (ATMEL 1 -MARSTA. doc) Tpot: K, Kelvin, 1, 180, 360, 999, Potential temperature (ATMEL 1 -WANK. doc) Tepot: K, Kelvin, 1, 180, 360, 999, Equipotential temperature (ATMEL 1 -WANK. doc) p: mb, millibar, 1, 100, 1200, 9999, Air pressure near the station RH%, %, 1, 0, 100, 999, Relative humidity quantitylabel, unit, decimals, lowconstraint, highconstraint, missing[, explanations] DDR, ATMEL 1, 20041228 h 0, 24, 1800, Average during full hour, first period 00: 00 -01: 00 hw, 24, 0 Average during full hour, first period 23: 30 -00: 30 regimelabel, valuesperday, reference[, explanations]

Air Ion Measurements at Tahkuse Hyytiälä 2005 Tahkuse is located in a sparsely populated Air Ion Measurements at Tahkuse Hyytiälä 2005 Tahkuse is located in a sparsely populated rural region, 27 km northeast of the city of Pärnu. The first measurements of air ions were carried out 1984. The first period of systematic measurement of small natural air ions was June 10, 1985 to June 2, 1986. The average spectrum of positive and negative air ions of mobility 0. 32– 3. 2 cm 2 V– 1 s– 1 at Tahkuse during June–September 1985.

First observations of bursts of intermediate ions at Tahkuse Hyytiälä 2005 Hourly average 13 First observations of bursts of intermediate ions at Tahkuse Hyytiälä 2005 Hourly average 13 June 1985 at 03 a. m. Hourly average 05 September 1985 at 05 p. m. Tammet, H. , Salm, J. and Iher, H. (1988) Observation of condensation on small air ions in the atmosphere. In Atmospheric Aerosols and Nucleation. Lecture Notes in Physics, Springer. Verlag, Vienna, 309, pp. 239– 240.

Tahkuse: Hyytiälä 2005 Tahkuse: Hyytiälä 2005

Tahkuse today: An extended instrumentation for measurements of the air ion spectra in Hyytiälä Tahkuse today: An extended instrumentation for measurements of the air ion spectra in Hyytiälä 2005 a wide mobility range is running from 1988. Main instruments are: • Air ion spectrometer with a mobility range of 0. 00032 -3. 2 cm 2 V-1 s-1, • NO 2 concentration meter designed at the University of Turku, • Ozone meter M-83 for measurements of total column ozone, • Pyranometer M-80 M, • Sensors of wind, temperature, pressure, and humidity, • Devices for collection of precipitations. The data are saved as average values every 5 min. Selected publications Hõrrak, U. , H. Iher, A. Luts, J. Salm, and H. Tammet (1994) Mobility spectrum of air ions at Tahkuse Observatory, J. Geophys. Res. , 99, 10679– 10700. Hõrrak, U. , J. Salm, and H. Tammet (1998) Bursts of intermediate ions in atmospheric air, J. Geophys. Res. Atmospheres, 103, 13909 -13915. Hõrrak, U. , A. Mirme, J. Salm, E. Tamm, and H. Tammet (1998) Air ion measurements as a source of information about atmospheric aerosols, Atmos. Res. , 46, 233 -242. Hõrrak, U. , Salm, J. and Tammet, H. (2000) Statistical characterization of air ion mobility spectra at Tahkuse Observatory: Classification of air ions. J. Geophys. Res. Atmospheres 105, 9291– 9302. Hõrrak, U. , Salm, J. , Tammet, H. (2003) Diurnal variation in the concentration of air ions of different mobility classes at a rural area. J. Geophys. Res. Atmospheres, 108(D 20), 4653. Hõrrak, U. (2001) Air Ion Mobility Spectrum at a Rural Area. Ph. D Thesis, University of Tartu.

From thesis by Hõrrak: Hyytiälä 2005 Average mobility spectra of air ions at Tahkuse. From thesis by Hõrrak: Hyytiälä 2005 Average mobility spectra of air ions at Tahkuse. Sept. 1993 – Oct. 1994.

Tahkuse: comparison of air ion and aerosol instruments Hyytiälä 2005 From: Hõrrak, U. , Tahkuse: comparison of air ion and aerosol instruments Hyytiälä 2005 From: Hõrrak, U. , Mirme, A. , Salm, J. , Tamm, E. and Tammet, H. (1998) Air ion measurements as a source of information about atmospheric aerosols. Atmos. Res. 46, 233– 242.