Phase Relationships in Sea Ice as a Function of Temperature

Abstract

ABSTRACT. Quantitative m eas ure m ents of the liquid water phase in a sa mple of sea ice w e r e m a de with a nucl ea r m a gn e ti c resonance sp ec tro met el'. The m ea sure ments a re used to co mpute the phase relationships in sea ice as a fun ction of tempe ra ture. A mod el for sea-wa ter based upon a mixture of seven binary sa lts is used for these computati ons. Th e n .m .1' . meas urem e nts a re related to th e so lva tion water wh ic h is associated with each bin a r y sa lt. This so lva tion wa leI' is bound to th e sa lt in a pse ud o-crysta lline stru c ture, with the a mount of w a ter d etermin ed by th e eut eCl ic concentration of the sa lt. Th e results a re give n in tabular form a nd differ so m ewha t from previously published ta bl es. Two controve rs ia l h ydrated sa lts w e re added to the table, based o n the n.m. r. data . RESUME:. Rela liolls enlre phases dalls la glace de Iller el/ fo llclioll de la lelllperalllre. Les mesures qu a ntita ti ves de la phase c1e I'ea u liqui dc clans un echantill on d e la gla cc d e mer ont be fait es avec un spectrom e tre nucleaire a rt'sonnance magnetiquc. Les m es ures so nt uti lisees a ca lculcr Ics rela ti ons e ntre ph ases dans la g lace de mer en fonc tion de la tem peratu re. Un modelc c1'eau d e m e r b ase sur un m e lange de sept sels binaires est emp loye pour ces ca lcu ls. Les mes ures d e R .M .N. sont en re lati o n a,'cc l'ea u d e di ssoluti on qui es t assoc iee a chaqul' sel bin a ire. C e lte ea u de di sso luti o n es t liee a u sel dans un e structure p seudo-crista llin e. la qua ntite d 'eau etant c1eterm inee pa r la conce ntra tion e utec tiqu e du scl. Lcs resulta ts so nt donnes sous forme de tablea u ct sont un pe u differents des ta bles publ iees a upa ra \'a nt. Sur la base d cs d o nn ees R .M.N .. d e ux sels hydra tes controve rses ont e te rajoutes a la ta ble.7.USAMME NFASSUNG . Pha sellbez ie/Illllgell illl lvleerei" als Fllllklioll der T emperalllr. Quantitative M ess ungen c1er f-lU ss igen V\'asse rphase in e in e r M ee reisprobe wurd e n mi l cin cm ke rnm a gnctischen R eson a nzsp ektrome ter ,·o rgenomm e n. Di e Mess unge n w e rde n c1azu benut z t. di e Ph ase nbez ichungc n im M eereis a ls Funktion del' T empera tur z u berechn en. Ein Mod ell fUr M ecrw assc r a uf c1er G rund lage eines G emenges vor sieben ZweislOff-Sa lzen wircl fUr c1iese Be rec hnungen be nutc t. Di e kernmagn e t isc hen R esonanzmessungen sincl a bhangig vo n dem Liisungswasser , d as in j ccl cm cl e r Zwc isto fT-S a lzc vo rko mmt. Dieses Liis ungswasser ist in Form eine r Psc ucl okrista ll-Struktur an c1i e Sa lze gcb undcn . wobe i 'e in e M enge durch di e eutektischc Kon zc ntra tio n des Sa lzes bes timmt ist. Di e Erge bnisse sincl in tabell a risch e r Form da rges te ll t ; sic unterschieclen sic h e twas \'o n {'rUhe r h e ra usgcgebene n T a b e ll c n. Zwe i zwe ife lh a ft e hyd ratisc h e S a lz!' wurclen aufgruncl d e l' k!'rnm ag netisc he n R eso na nzm ess unge n in di e Tabell e mit a ufge nommen...

A year‐long record of size‐segregated aerosol composition at Halley, Antarctica

“…Although in the past sea‐salt aerosol around Antarctica has generally been assumed to have been produced by bubble bursting at the air sea interface (the dominant mode of production in lower latitudes), it is now believed that the major source of aerosol to the Antarctic atmosphere is concentrated brine expelled to the surface of newly‐forming sea ice, and the delicate ice crystals (frost flowers) that grow from this brine [ Wagenbach et al , 1998a; Rankin et al , 2002]. At low temperatures, salts begin to precipitate from the brine, with mirabilite (Na 2 SO 4 .10H 2 0) being lost below −8°C and sodium chloride fractionating below −23°C [ Richardson , 1976].…”

The Pacific Arctic Region

“…Moreover, based on a salinity-oxygen isotopic study, Yamamoto-Kawai et al ( 2009b ) concluded that the sea-ice melt component of surface water in the southern part of the Canada Basin has increased at a mean rate of 0.27 m/year in the top 50-m of the water column since 1987. Theoretically, the cold brine solution leads to chemical oversaturation and precipitation of CaCO 3 (Richardson 1976 ). Theoretically, the cold brine solution leads to chemical oversaturation and precipitation of CaCO 3 (Richardson 1976 ).…”

Year‐round records of bulk and size‐segregated aerosol composition and HCl and HNO3 levels in the Dumont d'Urville (coastal Antarctica) atmosphere: Implications for sea‐salt aerosol fractionation in the winter and summer

“…However, this difference can also result from warmer temperatures at DDU (−15°C instead of −20°C at NM from May to October [ Konig‐Langlo et al , 1998]). Warmer temperatures can lead to either more frequent dilution by unfractionated frost flowers (present above −8°C) or less efficiency of the fractionation process since the sulfate to sodium ratio was found to decrease from 0.13 at −11°C to 0.07 at −14°C [ Richardson , 1976]. …”