Kriews, Michael

Lüdke, C.

Skole, J.

Taubner, K.

English

Electronic Publication Information Center

  	  The influence on climate, ecosystems and human health by atmospheric particles is undoubted but measurements to quantify the emission from natural and anthropogenic sources as well as the transport- and deposition behaviour are still incomplete.Diverse natural sources are known to emit particles into the atmosphere, for instance volcanism, soil dust, vegetation burning, and sea spray. Additional an increasing number of anthropogenic sources emit particles into the atmosphere, like coal or oil combustion, refuse incinerators, industrial processes such as ore dressing etc. and transport processes including all mobile sources. These processes generate the predominant part of metallic trace elements bound to particles in the air. The composition of aerosol particles is determined by the course of chemical and physical reactions occurring in particle generation and transportation. In order to study such aspects as relevant sources, the transport of aerosols, their atmospheric deposition and their effects on man and environment, it is necessary to analyse different measurable properties of aerosol particles, for instance size distribution, chemical composition, isotope ratio, etc. Varying sampling conditions caused by changing meteorological conditions or sampling locations causes a need for short sampling times. Therefore powerful analytical techniques are imperative for time-resolved measurements.In the present work aerosol particles were characterized for their morphological shape by scanning electron microscope (SEM) and analysed for the main components by energy dispersive x-ray analysis (EDXA). Trace elements were quantified more precisely by the application of electrothermal evaporation combined with inductively coupled plasma mass spectrometry (ETV-ICP-MS).For application of ETV-ICP-MS to size fractionated particle analysis a modified eight-stage cascade impactor was used. Small separate graphite discs first act as an impaction target serve in a second step as a platform in the ETV and permit the particle analysis without any sample preparation. The main goal of our investigations was to characterize the chemical composition of size fractionated aerosol particles as well as to quantify trace metal fluxes over the Atlantic Ocean (50°N-30°S) during leg ANT XVII/1 in Dec. 99/Jan. 2000 from Bremerhaven (FRG) to Cape Town (South Africa) on board R.V. Polarstern.	 ﬀﬁ ﬂﬃ  !  "# $ % & % '& ( )+*' , -.% -0/% ( $ 132 4 5% ' ( $ & 6 # $ -Aerosol sampling was carried out daily at the Peildeck in 22 m above sea level. The pump rate for  the eight stage impactor was 2.2 m3/h.To avoid contaminations from the stack the equipment was  shut down when the wind was blowing from the rear. "# $ % & % '& ( )+*' , -.% -0/% ( $ 132 4 5% ' ( $ & 6 # $ -$QDO\VLVRIVL]H FODVVLILHG DHURVRO SDUWLFOHV FROOHFWHG LQWKH $WODQWLFDLUIURP 160 .ULHZV& /GNH- 6NROH.7DXEQHU 7$OIUHG:HJHQHU,QVWLWXWHIRU 3RODU DQG0DULQH5HVHDUFK$P+DQGHOVKDIHQ'%UHPHUKDYHQ,QVWLWXWHIRU6SHFWURFKHPLVWU\ DQG$SSOLHG 6SHFWURVFRS\$OEHUW(LQVWHLQ6WUDH'%HUOLQ7 *HVHOOVFKDIW]XU)|UGHUXQJDQJHZDQGWHU2SWLN2SWRHOHNWURQLN4XDQWHQHOHNWURQLNXQG6SHNWURVNRSLHH95XGRZHU&KDXVVHH'%HUOLQ8 9;:<9  =  "# $ % & % '> ?( $ ( > 6 # $ , & ( 6 , % -3/@3ABCED BFG"Morphological characterisation of aerosol samples as well as determination of main components were performed by SEM/EDXA.HIJﬁK ﬃ  K=  !  C<% $ *?% ' % . , > ( '( -1L);( , -M> % );*% - # - 61 # 6 # $ )+, -( 6 , % -/@3A BCED BFG"Typical aerosol particles from anthropogenic sources, sea salt as well as from mineral dust are shown together EDXA spectra in the following section. Single particle analysis show the source distribution for the northern- and southern hemisphere as well as for the region of Saharan dust.A BCN*, > 6 O$ #P % $6 @ *, > ( '& # (& ( ' 6( -10)+, - # $ ( '1O& 6*( $ 6 , > ' # &P $ % )Q6 ? #A( ?( $ ( -01O& 6$ # . , % -R )+*( > 6 % $S3T ! = U VW ! S U XJY W & 6 ( . #=  Z [\); BFG"]& *# > 6 $ (P % $6 @ *, > ( '& # (& ( ' 6( -1)+, - # $ ( '1O& 6*( $ 6 , > ' # &10514055121LOD pg/m³MeasuredisotopeLOD pg/m³Measuredisotope1 0.11301SbMn0.8RhCo590.21112050.053 0.60.031071950.2CePdPtAg0.20.5208118TlCdPbSn^, )+, 6 &% Pﬁ1 # 6 # > 6 , % -W /( & # 10% -36 ? #= _> $ , 6 # $ , (C`# ( -3# ' # )+# - 6> % -> # - 6 $ ( 6 , % -&, -+( # $ % & % ' *( $ 6 , > ' # &T *. D )0a Y    "# $ % & % '> ?( $ ( > 6 # $ , & ( 6 , % -3/@Bb4c R d5ﬁc C<ACharacterisation of aerosol samples was carriedout for typical tracer elements by ETV-ICP-MS:(mineral dust: Mn, Cs, Sn; sea salt: Sb and In;anthropogenic sources: Pb and Ag).PlasmagasICP  torch  supplySystem computerPump Pump Turbo pumpQuadrupoleElan 5000 Turbo pumpIon lensesRFStabilizationgasTargetAuxiliarygasPivotElectrothermal vaporizer LidBe *# $ , )+# - 6 ( '& # 6 O*0P % $Bb4c R 45ﬁc C<AImpaction area Graphite tube containerGraphite targetFixing slitsParticulatesInjection holef$ ( *? , 6 #6 O/#P % $Bb4c R 45ﬁc C<AA BCN*, > 6 O$ #P % $6 @ *, > ( '( - 6 ?$ % *% . # -, >*( $ 6 , > ' # &P $ % )ﬀ? , . ?36 # )+*# $ ( 6 O$ #> % )+/O& 6 , % -0*$ % > # & & # &R )+*( > 6 % $[3T Z U AW g U X]Y W & 6 ( . #! h  [\); BFG"]& *# > 6 $ (P % $6 @ *, > ( '( - 6 ?$ % *% . # - , >*( $ 6 , > ' # &=    b$ ( > ## ' # )+# - 6( -( ' @ & , &/@Bb4c R d5ﬁc C<ASelected trace element concentrations measured by ETV-ICP-MS are shown in the following section. The constant distribution along the route for In seems to be an indicator that this element can be a tracer for sea salt.  In contrast to that Ag represents a tracer for anthropogenic sources. Its concentration is higher in the more industrialized northern hemisphere. Sn and Cs represent tracer for geogenic elements. There are remarkable maxima in the innertropical convergence zone (5°-10°N), where east wind transports Saharan dust to the open ocean.-40-200204060AgInij k l m k ln o p qrAgs t l u l v w mx j y l z10100010000100100010000 In-40-200204060110100100010000100000SnCs{| } ~  } ~      ~  ~   Ł |  ~ A *( 6 , ( '1 , & 6 $ , /O 6 , % -0P % $/O' 0# ' # )+# - 6> % -> # - 6 $ ( 6 , % -&, -;( # $ % & % '*( $ 6 , > ' # &%  # $6 ? #"6 ' ( - 6 , >% > # ( -3P $ % )[  U Vc =  U AA> ? # );( 6 , >1 , ( . $ ( )ﬀ% P6 ? #> ( & > ( 1 #, )+*( > 6 % $A BCN*, > 6 O$ #% Pﬁ(. $ ( *? , 6 #6 ( $ . # 6, 6 ?3, );*( > 6 # 13*( $ 6 , > ' # &2# . , % -( '( -10& % O$ > #1 , & 6 $ , /O 6 , % -+% P6 ? #);(  % $> % )+*% -# - 6 &P % $( # $ % & % ' *( $ 6 , > ' # &, -6 ? #"6 ' ( - 6 , >( , $( -( ' @& # 13/@0A BCED BFG"    mineral dustsea saltanthropogenicsulphate          ¡ ¢   £ ¤ ¥  ¢ £ ¦§¨ ©  ª   « ¬   ­ «¨ ® ¡ ¯    ° ±  ² §³ ´µ ¶ ´³ ´· ¸ ´mineral dustsea saltanthropogenicsulphate        ¹ ¡   º £ ¤ ¥ ¢ £ ¦§» ¼ ± ²®© ½ ¾ ½  ¼ ¼¨²¿ ¿ ÀÁ ÀÂ Â Àmineral dustsea saltanthropogenicsulphate       Ã ¡   £ Ä ¥ Å £ ¦§ª¨©  ª   « ¬   ¾  ¼ ± ¨©  °   ÆÇ È ÀÁ ÀÁ Àmineral dustsea saltanthropogenicsulphate        ¡ É Ã £ Ä ¥  Ê £ » §ª¨©  ª   « ¬   Ë Ì «¨® Í¡ ¤  Î® §ÏÀÐ ÀÁ Àmineral dustsea saltanthropogenicsulphate       º ¡  ¢ £ ¤ ¥  º £ ¦§ª¨©  ª   « ¬   Ñ  Ò  ¡ Ä¨¼¨±  ² §ÓÔ Õ Ö × Ø× ÙÚ Û Ü Û Ý Û ØÞß à áâ× Ý á Üﬁã á ä Û Ø á Ö åÚ × ß á Üã á ä Û Ø á Ö åd% O$ & #*' % 6P % $"VbG4R R D !P $ % )æ! Z  !   S S c  h  !   3T $ # 13' , - # Y( -13ç [ 3)+/( $/( > ( $ 16 $ (  # > 6 % $ , # &T !  ?W . $ # # -3' , - # & YImpactor 18Impactor 14Impactor 9Impactor 5Impactor 1èMé;êMëìîíïëð ñ;òMëó ôõéLöëìîíïëﬁð ñ;òMëó ôèMñ;ìEñLöñ;òø÷ïêEùëEúïûü;ó é;ò¡   º £ ¤ ¥ ¢ £ ¦§» ¼ ± ²®© ½ ¾ ½  ¼ ¼¨²¡ ¢   £ ¤ ¥  ¢ £ ¦§¨ ©  ª   «¬   ­ «¨ ®  ¡ ¯    ° ±  ² §¡ É Ã £ Ä ¥  Ê £ » § ª¨©  ª   «¬   Ë Ì «¨® Í ¡ ¤  Î® §¡   £ Ä ¥ Å £ ¦§ ª¨©  ª   «¬   ¾  ¼ ± ¨©  °   Æ¡  ¢ £ ¤ ¥  º £ ¦§ª¨©  ª   «¬   Ñ  Ò   ¡ Ä¨¼¨±  ² §A *( 6 , ( '( -1+& , ý #1 , & 6 $ , /O 6 , % -+% Pﬁ& % )+#& # ' # > 6 # 16 $ ( > ## ' # )+# - 6 &, -+( # $ % & % ' *( $ 6 , > ' # &, -36 ? #"6 ' ( - 6 , >( , $( -( ' @ & # 1J/@<Bb4c R d5ﬁc C<A C`-]( -1]d&L( $ #M6 $ ( > # $ &;P % $M)+, - # $ ( '31O& 6 WR -]P % $E& # (<& ( ' 6L( -1]5ﬁ/$ # *$ # & # - 6 &3( - 6 ?$ % *% . # - , >+, -P ' O # -> #  b$ ( > #+# ' # )+# - 63> % -> # - 6 $ ( 6 , % -&# $ #;-% $ );( ' , ý # 16 %;6 ? #L> ' ( & &, 1 6 ?&% P6 ? ## , . ? 6, )+*( > 6 % $& ( )+*' , -.& 6 ( . # &  þß  	  	  Size classified sampling of aerosol particles on separate graphite targets andsubsequent multielement analysis is a useful tool for the characterization of aerosol particles. Morphological studies were carried out by SEM. Major element content of single particles were characterized by EDXA. Trace element concentrations were determined by ETV-ICP-MS directly from the aerosol loaded graphite targets.The high efficiency of the sampling system combined with the powerful analytical technique permits the study of isotope correlations allowing the identification of particle sources as well as transport and deposition processes in a high time and spatial resolution.Further improvements can be expected by using time of flight (TOF) mass spectrometer. TOF-instruments work truly simultaneously and are not limited in the number of measurable isotopes in fast transient signals.5. AcknowledgementWe would like to thank T. Adam and U. Bock (AWI) for assistance in SEM operation and EDX analysis. Many thanks to the crew of R.V. Polarstern for their help in setting up our instruments and providing logistical support. The financial support given by the DFG is gratefully acknowledged.103

Analysis of size classified aerosol particles collected in the Atlantic air from 50°N-30°S.

Abstract

Similar works

Full text

Available Versions

Electronic Publication Information Center