News & Events

Nitrate in snow under photolysis: Field, laboratory and isotopic perspectives

Monday, March 31, 2014, 12:00PM - 1:00PM

Speaker

Jöel Savarino

Laboratoire de Glaciologie et Géophysique de l’Environnement, St Martin d’Heres, France

Location:

ARC room 620

Particulate nitrate (p-NO3) and nitric acid gas (HNO3) are ubiquitous in nature. In atmospheric chemistry, their principal interest resides in the fact that they constitute the end products of the oxidation chain of the nitrogen oxides, the latter being a precursor of the tropospheric ozone. It has been speculated that the analysis of nitrate in ice cores could be used as a proxy of the past NOx concentration in the atmosphere and thus reveal the past oxidation capacity of the atmosphere. Unfortunately, nitrate in snow is not stable and can undergo post-depositional processes. In order to understand the significance of nitrate in ice cores, in recent years we have conducted a series of experiments combining field, laboratory, stable isotope analysis and theoretical studies. After a short review, the main results of this research work will be presented.
 

Audience

Free and open to the public.