Astronomical observatory of National Taras Shevchenko university - PowerPoint PPT Presentation

V. Danylevsky Astronomical observatory of National Taras Shevchenko university Kyiv, Ukraine vdanylevsky@gmail.com Astronomy and space physics in Kyiv university conference May 24 – 27, 2016 Kyiv, Ukraine

Kyiv AERONET / PHOTONS site Location: Main astronomical observatory of National academy of Science of Ukraine, Holosiiv forest,  10 km southward of the city center Start of observations: March 29, 2008 Instruments: CIMEL CE 318 polarized model (8 filters): 440, 675, 870, 870 (polarisation), 940, 1020 nm CIMEL CE 318 standard model (5 filters): 440, 675, 870, 940, 1020 nm CIMEL CE 318 standard model (8 filters): 340, 380, 440, 500, 675, 870, 940, 1020 nm CIMEL CE 318N (9 filters): 340, 380, 440, 500, 675, 870, 936, 1029, 1640 nm Mar 29, 2008 – Apr 02, 2009 P043 (CE 318, polarized) Apr 21, 2009 – Apr 22, 2010 P040 (CE 318, polarized) Apr 23, 2010 – Aug 26, 2011 P074 (CE 318, 5 filters) Sep 12, 2011 – Aug 29, 2012 P040 (CE 318, polarized) (&Sep 21, 2011 – Nov 17, 2011 P715 (CE 318N)) Sep 04, 2012 – Jul 29, 2013 P077 (CE 318, 5 filters) Jul 30, 2013 – Nov 10, 2014 P079 (CE 318, 8 filters) Nov 24, 2014 – Nov 08, 2015 P715 (CE 318N)

Aerosol climatology parameters AOT – Aerosol Optical Thickness (  a ) and its spectral dependence are the most relevant climatic characteristics of aerosols because they define the Earth’s surface irradiance (Bouger law)   H r        max   2 r                           2 r Q , m N ( r , h ) dr dh a I I exp    a 0     CosZ S 0 r min H – atmosphere column geometrical height; Z S – the zenit angle of the Sun; N(r) – aerosol particle radius distribution; Q(…) – particles extinction efficiency factor; m(  ) – particles complex spectral refractive index Acceptable uncertainties of AOT determination  ≈ 0.01 over ocean; 0.03 over land Climatic significant radiance flux variations on the Earth’s surface ≈ 0.25 W/m 2 Astronomy and Space Physics in Kyiv university, May 24 - 27, 2016, Kyiv, Ukraine

Aerosol climatology parameters The Angstrom exponent (  ) Angstrom empirical formula of AOT spectral dependence              1 m a a From AERONET measurements  1 = 870 nm,  2 = 440 nm           lg /   a 2 a 1     lg / 1 2 Astronomy and Space Physics in Kyiv university, May 24 - 27, 2016, Kyiv, Ukraine

Kyiv AERONET/PHOTONS Number of observations L2.0 per month site averaged over 2008 - 2015 Statistics of the direct Sun observations Number days of observations L2.0 per months averaged over 2008 - 2015 Number of observations L2.0 every year

Kyiv AOD 440 nm statistics Density function of the AOD 440 nm distribution (over all points during all time of observations) The most probable AOD 440 nm are 0.1 to 0.2 Density functions of AOD 440 nm distribution for each year (all points used) 0.1 to 0.2 are the most probable every year. Wild fires influence is revealed in 2010

Kyiv AOD 440 nm statistics Yearly averaged data, (all points used, 10 months for 2015) AOD decrease during 2008 – 2015 (?) 2010 – wild fire influence Averaged data over 2008 – 2015 for each month (all points). Two maximums are every year: in Spring (April) and in the last of Summer (August)

Angstrom Exponent (440 – 870 nm) statistics Density function of the AExp distribution (over all points during all time of observations ) The most probable AExp are 1.4 to 1.8 Density functions of AExp distribution for each year (all points used). 1.4 to 1.8 are the most probable every year. But two groups of distributions are noticeable AExp max are 1.4 to 1.6 in 2009 – 2012; 1.6 to 1.8 in 2008, 2013, 2014

Angstrom Exponent statistics Yearly averaged data (all points used) AngExp decreases during 2008 – 2010 And increases during 2010 – 2015 (?) 2010 – wild fire influence Averaged data over 2008 – 2015 for each month (all points). Two maximums are every year: in Spring (April) and in the Summer (July&August)

Particles effective radius statistics Reff total computed from all points data Level 2.0 The most probable values 0.2 to 0.3 µm Difficult to comment the year to year variations – StdDev are very large

Particles size distribution   2      1 1 ln r ln r         0 n r exp   Log-normal law              2 r 2 r r  

SSA 440 nm statistics Statistics of daily averaged data Level 2.0, Only 104 values are obtained over all time of observations. The most probable values are 0.92 to 0.96. Minimal values are in winter (February) (?) Maximal values are in the autumn (?) Spectral dependence are important, did not consider here.

AOD 440 nm and Angstrom exponent 440 – 870 nm at different sites comparison AOD 440 nm yearly values and behavior over Kyiv site are similar to other European urban sites, It is much lover then over China sites and considerably higher then over clear air sites at Hawaii and Australia. AExp of aerosol particles over the world are very various. AExp over Kyiv has medium values

Direct Radiative forcing (TOA) comparison

Luhansk site (The East of Ukraine) Nov 21, 2011 to Aug 21, 2013 All points of AERONET data level 2.0 The most probable values are: AOD 440 nm 0.1 to 0.3 AExp 1.3 to 1.7 Reff 0.2 to 0.3 µm

Martova site (The East of Ukraine,Kharkiv region) Dec 11, 2011 to Dec13, 2014 All points of AERONET data level 2.0 The most probable values are: AOD 440 nm 0.1 to 0.2 AExp 1.4 to 1.8 Reff 0.2 to 0.3 µm

Aerosol optical properties from Microtops II measurements V. Bovchaliuk, A. Bovchaliuk, G. Milinevsky et al. Advances in Astronomy and Space Physics, 3, 46-52 (2013) Aerosol characteristics in the atmosphere over Chornobyl region Angström Period AOT exponent 340 nm 440 nm 675 nm 870 nm 1020 nm 440 – 870 nm 03.06.2011 - 06.06.2009 0.23 0.07 0.20 0.05 0.12 0.03 0.07 0.02 0.05 0.02 1.55 0.78 30.05.2011 – 03.06.2011 0.26 0.12 0.18 0.08 0.10 0.04 0.06 0.02 0.06 0.02 1.61 1.18 25.05.2012 – 03.06.2012 0.26 0.05 0.20 0.04 0.12 0.02 0.07 0.02 0.08 0.01 1.58 0.56 23.06.2012 – 24.062012 0.25 0.06 0.18 0.03 0.10 0.01 0.05 0.01 0.06 0.01 1.92 0.51 AOT and Angström exponent values in the atmosphere over Rivne Angström Period AOT exponent 340 nm 440 nm 675 nm 870 nm 1020 nm 440 – 870 nm 27.06.2011 - 05.07.2011 0.42 0.10 0.30 0.07 0.16 0.04 0.10 0.03 0.11 0.03 1.60 0.77 10.09.2011 – 13.09.2011 0.29 0.07 0.21 0.05 0.12 0.02 0.08 0.01 0.08 0.02 1.48 0.63 04.07.2012 – 11.07.2012 0.40 0.09 0.29 0.07 0.16 0.04 0.10 0.03 0.09 0.03 1.63 0.76

Aerosol optical properties from Microtops II measurements V. Bovchaliuk, A. Bovchaliuk, G. Milinevsky et al. Advances in Astronomy and Space Physics, 3, 46-52 (2013) Aerosol characteristics in the atmosphere over Odessa Angström Period AOT exponent 440 nm 675 nm 870 nm 936 nm 1020 nm 440 – 870 nm 26.07.2009 – 30.07.2009 0.18 0.06 0.13 0.05 0.12 0.05 0.11 0.05 25.08.2009 – 15.10.2009 0.16 0.06 0.11 0.05 0.11 0.05 0.11 0.05 13.11.2009 – 19.11.2009 0.25 0.09 0.17 0.10 0.13 0.10 0.12 0.09 0.95 1.53 28.05.2010 – 15.06.2010 0.14 0.05 0.10 0.04 0.12 0.04 0.13 0.05 12.08.2010 – 26.08.2010 0.25 0.15 0.18 0.10 0.17 0.09 0.16 0.07 15.09.2010 – 18.09.2010 0.20 0.09 0.14 0.05 0.14 0.05 0.15 0.04 05.06.2011 – 06.06.2011 0.27 0.04 0.15 0.02 0.09 0.02 0.08 0.02 1.69 0.47 01.08.2011 – 06.08.2011 0.20 0.05 0.11 0.02 0.07 0.02 0.07 0.01 1.59 0.58

Conclusions 1. Participation in the AERONET/PHOTONS program and collaboration with LOA of University Lille 1 gave us a good chance to study aerosols in the atmosphere over large area of Ukraine and to contribute to the international data base. 2. Contamination of the atmosphere over Ukraine with aerosols is similar to others areas of Eastern Europe and the aerosols properties (and sources of aerosols) are very similar too. 3. Aerosol spatial distribution over Ukraine is approximately uniform but special events of aerosol loading occur from time to time associated with fires and aerosol particles transport by the air flows. 4. Observations over Kyiv AERONET/PHOTONS site suggest on the negative trend of the AOD during 2008 – 2015.

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