Home |  English version |  Mappa |  Commenti |  Sondaggio |  Staff |  Contattaci Cerca nel sito  
Istituto sull'inquinamento atmosferico

Torna all'elenco Contributi in rivista anno 2014

Contributo in rivista

Tipo: Articolo in rivista

Titolo: Nitrate postdepositional processes in Svalbard surface snow

Anno di pubblicazione: 2014

Formato: Elettronico

Autori: Bjorkman, M.P., Carmen P. Vega, Kuhnel, R., Spataro, F., Ianniello, A., Esposito, G., Kaiser, J., Marca, A., Hodson, A., Isaksson, E., and Tjarda J.R.

Affiliazioni autori: C.N.R.-Istituto sull'Inquinamento Atmosferico, Roma, Italy,

Autori CNR:

  • GIULIO ESPOSITO
  • ANTONIETTA IANNIELLO
  • FRANCESCA SPATARO

Lingua: inglese

Abstract: The snowpack acts as a sink for atmospheric reactive nitrogen, but several postdeposition pathways have been reported to alter the concentration and isotopic composition of snow nitrate with implications for atmospheric boundary layer chemistry, ice core records, and terrestrial ecology following snow melt. Careful daily sampling of surface snow during winter (11-15 February 2010) and springtime (9 April to 5 May 2010) near Ny-Ålesund, Svalbard reveals a complex pattern of processes within the snowpack. Dry deposition was found to dominate over postdeposition losses, with a net nitrate deposition rate of (0.6 ± 0.2) ?mol m2 d1 to homogeneous surface snow. At Ny-Ålesund, such surface dry deposition can either solely result from long-range atmospheric transport of oxidized nitrogen or include the redeposition of photolytic/bacterial emission originating from deeper snow layers. Our data further confirm that polar basin air masses bring 15N-depleted nitrate to Svalbard, while high nitrate ?( 18O) values only occur in connection with ozone-depleted air, and show that these signatures are reflected in the deposited nitrate. Such ozone-depleted air is attributed to active halogen chemistry in the air masses advected to the site. However, here the Ny-Ålesund surface snow was shown to have an active role in the halogen dynamics for this region, as indicated by declining bromide concentrations and increasing nitrate ?( 18O), during high BrO (low-ozone) events. The data also indicate that the snowpack BrO-NOx cycling continued in postevent periods, when ambient ozone and BrO levels recovered.

Lingua abstract: inglese

Pagine da: 953

Pagine a: 976,

Pagine totali: 24

Rivista:

Journal of Geophysical Research. Atmospheres Wiley; [poi] American Geophysical Union
Paese di pubblicazione: Stati Uniti d'America
Lingua: inglese
ISSN: 2169-8996

Numero volume: 116

Numero fascicolo: 12

DOI: 10.1002/2013JD021234

Referee: Sì: Internazionale

Stato della pubblicazione: Published version

Parole chiave:

  • snow chemistry; nitrate; postdeposition; BrO chemistry; photolysis; Svalbard

URL: http://dx.doi.org/10.1002/2013JD021234

Data di accettazione: 15/10/2014

Strutture CNR:

Moduli:

Allegati: Bjorkman_2014 (application/pdf)

 
Torna indietro Richiedi modifiche Invia per email Stampa
Home Il CNR  |  I servizi News |   Eventi | Istituti |  Focus