CANADA. Amundsen Gulf. March April 2008. International scientific expedition going to and aboard the canadian coast guard icebreaker AMUNDSEN.

Légende écrite par les deux scientifiques en actiion au pied du brs-ise glace :

AIR MEASUREMENTS OF MERCURY
Alexandra (Sandy) Steffen and Debbie Armstrong

Plain language summary:
Mercury (Hg) is a contaminant found at elevated levels in the tissues of aquatic animals in the Arctic. The goal of this study is to continue measuring the levels of Hg in the Arctic air to determine whether these levels change with time and from where Hg is transported into the Arctic. As well, this study aims to understand what role the atmosphere plays in how Hg gets into the Arctic ecosystem. Mercury is found in the air as a gas or is attached to airborne particles. Globally, gaseous elemental mercury stays in the air for a long time but mercury found on particles and other forms of mercury can quickly fall onto the snow/ice surfaces. Once it falls, this mercury may enter the food chain. This study will provide data to assess how much mercury is in and brought into the Arctic air and how much falls onto the snow surfaces. The information generated from this study will contribute to understanding the impact that climate change will have on mercury contamination in the Arctic ecosystem and ultimately its effect on human health.

Off the Amundsen we are investigating Hg in the atmosphere using an instrument that pulls in air with a pump and collects it on a gold trap. We heat the traps to very high temperatures (900oC) and we can obtain different types of Hg in the air. Ultra high purity argon is used to transfer the mercury to the analysis cell in the instrument. We can detect levels of Hg in the parts per trillion and parts per billion levels with this instrumentation.

It was very challenging to put the system outside in the cold. Normally most of these instruments are inside a warm laboratory and only the silver box is outside b