A 210Pb database has recently been constructed and is now available. This base includes approximately 800 210Pb measurements of concentration in air at the Earth's surface, together with deposition flux both at the atmosphere‐Earth and water‐sediment interfaces. Here the data are analyzed and summarized. The atmospheric data (concentration and deposition flux) are presented for the different geographical areas when sufficient measurements are available. The trends are discussed in terms of mechanisms (sources, atmospheric circulation, and climate]. Water‐sediment data are classified into four types of water reservoirs which differ in their sedimentation mechanisms or in their in situ 210Pb production. The corresponding histograms are compared with the air‐surface flux histogram. This database points out the complete lack of information in some large areas of the planet.

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ABSTRACT. Thi s a rticle a ims to give a comp rehensive vi ew of the distributi on patte rns [or na tura l and artifical r a di onucl ides ove r Antarctica. \Ve foc us this stud y on 137 Cs, 210Pb and tritium . Appl ying vario us statistica l m ethods, we show th at the depositio n or rad ionuclid es revea ls a struc tured di stributi o n, although loca l d r ift red istributi on a nd the snow-s urface roughness disturb th e representati ve ness o f sa mpl es and produce a "noise" effec t. The depos iti on o f m C s over Anta rctica (885 TBq ) re presents O.OQ% of the to ta l depositio n of thi s radio nuclide in the wo rld a nd the cor rel a ti o n betwee n 1.37 Cs nuxes a nd acc umul ation shows two sub-popul ati o n s. For the stati o ns w ith a mean a nnu a l te mperature a b ove -21 QC, a stro n g correla ti o n is found, wh ereas th e co rrel a ti o n is lowe r for locati o n s vv ith tcm p e ra t u res below -21 DC . Th e nu x o f 210 Ph \'a ri es fro m 0.9 to 8.2 Bq m 1 a I with values stron g ly correlated w ith the acc umul a ti o n a nd a well-defin ed spati a l structure. Th e same m ec h a nism gove rns the depositi on o f a rtificial a nd n a tural tri tium but it clearl y differs from that of' oth er ra di onuclide assoc ia ted with parti c ul a te materi al.Th e "dr y fa ll-out" acco unt for between 60 a nd 80% or th e to ta l fa ll-out for th e artificia l radi onuc lides a nd a round 40 % for 2lo Pb. This difTerence is likel y related to a tropos pheric fr ac ti on for 21OPb. Despite its isolated locati on, the radi oacti ve f'a ll-out of ar tificial longli ved ra di onuclides ove r A nta rcti ca has b ecn te n tim es greater than for n a tural radiolluclides.

ABSTRACT. Thi s a rticle a ims to give a comp rehensive vi ew of the distributi on patte rns [or na tura l and artifical r a di onucl ides ove r Antarctica. \Ve foc us this stud y on 137 Cs, 210Pb and tritium . Appl ying vario us statistica l m ethods, we show th at the depositio n or rad ionuclid es revea ls a struc tured di stributi o n, although loca l d r ift red istributi on a nd the snow-s urface roughness disturb th e representati ve ness o f sa mpl es and produce a "noise" effec t. The depos iti on o f m C s over Anta rctica (885 TBq ) re presents O.OQ% of the to ta l depositio n of thi s radio nuclide in the wo rld a nd the cor rel a ti o n betwee n 1.37 Cs nuxes a nd acc umul ation shows two sub-popul ati o n s. For the stati o ns w ith a mean a nnu a l te mperature a b ove -21 QC, a stro n g correla ti o n is found, wh ereas th e co rrel a ti o n is lowe r for locati o n s vv ith tcm p e ra t u res below -21 DC . Th e nu x o f 210 Ph \'a ri es fro m 0.9 to 8.2 Bq m 1 a I with values stron g ly correlated w ith the acc umul a ti o n a nd a well-defin ed spati a l structure. Th e same m ec h a nism gove rns the depositi on o f a rtificial a nd n a tural tri tium but it clearl y differs from that of' oth er ra di onuclide assoc ia ted with parti c ul a te materi al.Th e "dr y fa ll-out" acco unt for between 60 a nd 80% or th e to ta l fa ll-out for th e artificia l radi onuc lides a nd a round 40 % for 2lo Pb. This difTerence is likel y related to a tropos pheric fr ac ti on for 21OPb. Despite its isolated locati on, the radi oacti ve f'a ll-out of ar tificial longli ved ra di onuclides ove r A nta rcti ca has b ecn te n tim es greater than for n a tural radiolluclides.

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