Airborne lidar measurements of surface ozone depletion over Arctic sea ice

Abstract

A differential absorption lidar (DIAL) for measurement of atmospheric ozone concentration was operated aboard the Polar 5 research aircraft in order to study the depletion of ozone over Arctic sea ice. The lidar measurements during a flight over the sea ice north of Barrow, Alaska, on 3 April 2011 found a surface boundary layer depletion of ozone over a range of 300 km. The photochemical destruction of surface level ozone was strongest at the most northern point of the flight, and steadily decreased towards land. All the observed ozone-depleted air throughout the flight occurred within 300 m of the sea ice surface. A back-trajectory analysis of the air measured throughout the flight indicated that the ozone-depleted air originated from over the ice. Air at the surface that was not depleted in ozone had originated from over land. An investigation into the altitude history of the ozone-depleted air suggests a strong inverse correlation between measured ozone concentration and the amount of time the air directly interacted with the sea ice

Lidar Measurements of Tropospheric Ozone in the Arctic

“…The ground based Differential Absorption Lidar (DIAL) instrument used for this study had a design that was essentially equivalent to the system employed for previous ship and aircraft based studies of ozone over sea ice [1,2]. A schematic diagram of the lidar is shown in Fig.…”

“…The ozone depletion has been explained as being caused by Bromine atoms that originate from photochemical reactions on snow and fresh sea ice surfaces [6]. The aircraft and ship based lidar measurements over the sea ice have found that the ODEs extend from the surface to heights of a few hundred meters [1,2]. Analyses of air trajectories revealed that ozone depleted air spent significant time in the surface layer over the frozen ocean surface and open leads [1,2].…”

“…The aircraft and ship based lidar measurements over the sea ice have found that the ODEs extend from the surface to heights of a few hundred meters [1,2]. Analyses of air trajectories revealed that ozone depleted air spent significant time in the surface layer over the frozen ocean surface and open leads [1,2]. The current study primarily concerns ground based lidar measurements of tropospheric ozone over Eureka Weather Station on Ellesmere Island.…”

“…One was installed on the Canadian Coast Guard Icebreaker Ship Amundsen [1] and on the Polar-5 (DC-3) aircraft [2] for studies of air chemistry over Arctic sea ice. Another lidar for ground-based measurements of tropospheric ozone was constructed for the Canadian Network for the Detection of Atmospheric Change (CANDAC) and installed as part of the Polar Environment Atmospheric Research Laboratory (PEARL) at Eureka Weather Station on Ellesmere Island in the Canadian Arctic.…”

Airborne Lidar Measurements of Pollution above the Oil Sands Region in Northern Alberta

“…A lidar system for tropospheric ozone and aerosol measurements was developed at York University for installation on aircraft [1,2]. This was installed on a Twin Otter aircraft in August 2013 for participation in a field campaign that was designed to study the air pollution from the oil sands extraction activities north of Fort McMurray, Alberta.…”