We are now approaching halfway through the aircraft campaign, with 5 science flights completed and three more planned before the Amundsen arrives at the mouth of Lancaster Sound on the evening of July 17. At that point, we will be re-directing our attention to sampling the plume from the ship, characterizing the ship emissions, how they evolve in the atmosphere, and, hopefully, how they affect cloud.
Each day flight planning starts at 6 pm with a weather forecast from Ralf Brauner, a meteorologist with us in Resolute who has worked with AWI on a number of campaigns. The weather situation is then confirmed at 8 am the next morning before the flight takes off. A high pressure system has been centred over Resolute since we arrived – we are very lucky – with lows swinging around us. Based on the forecast, we decide where to fly – so far either north to the polynas or south to the ice south of Cornwallis Island. With flights now completed over both solid ice and melting ice, we are turning our attention to the open water of Lancaster Sound. We observed particle nucleation and growth events in that region from the Amundsen in 2008, and hope to again but with vertical profile information from the plane. As well, we have been flying through cloud, both at 200 feet in fogs near the surface (thanks to the pilots, Kevin and John!) and through mid-level cloud, trying to connect the aerosol out-of-cloud to the droplet sizes and numbers in-cloud.
A typical flight profile, prepared by Richard Leaitch – who has been directing each flight on-board the POLAR6 – is shown above. Most flights go at least once to 9500 feet to provide vertical profile information, with one flight now completed to 20000 feet, at which point oxygen is needed (the cabin is unpressurized) and some of the instruments have to shut down because of potential electrical problems. Those flying each day are: Kevin and John (the pilots), Christian or Lucas or Jens (AWI engineer), Richard (Environment Canada), Megan and Julia (U of Toronto), Franzi and Heiko (Max Planck Institute at Mainz and U of Mainz).
-Jon Abbatt, NETCARE Priciple Investigator