Field and Satellite Observations of the Formation and Distribution of Arctic Atmospheric Bromine Above a Rejuvenated Sea Ice Cover

Recent drastic reduction of the older perennial sea ice in the Arctic Ocean has resulted in a vast expansion of younger and saltier seasonal sea ice. This increase in the salinity of the overall ice cover could impact tropospheric chemical processes. Springtime perennial ice extent in 2008 and 2009 broke the half-century record minimum in 2007 by about one million km2. In both years seasonal ice was dominant across the Beaufort Sea extending to the Amundsen Gulf, where significant field and satellite observations of sea ice, temperature, and atmospheric chemicals have been made. Measurements at the site of the Canadian Coast Guard Ship Amundsen ice breaker in the Amundsen Gulf showed events of increased bromine monoxide (BrO), coupled with decreases of ozone (O3) and gaseous elemental mercury (GEM), during cold periods in March 2008. The timing of the main event of BrO, O3, and GEM changes was found to be consistent with BrO observed by satellites over an extensive area around the site. Furthermore, satellite sensors detected a doubling of atmospheric BrO in a vortex associated with a spiral rising air pattern. In spring 2009, excessive and widespread bromine explosions occurred in the same region while the regional air temperature was low and the extent of perennial ice was significantly reduced compared to the case in 2008. Using satellite observations together with a Rising-Air-Parcel model, we discover a topographic control on BrO distribution such that the Alaskan North Slope and the Canadian Shield region were exposed to elevated BrO, whereas the surrounding mountains isolated the Alaskan interior from bromine intrusion

Development of the geoCamera, a system for mapping ice from a ship

The geoCamera produces maps of the ice surrounding an ice-capable ship by combining images from one or more digital cameras with the ship\u27s position and attitude data. Maps are produced along the ship\u27s path with the achievable width and resolution depending on camera mounting height as well as camera resolution and lens parameters. Our system has produced maps up to 2000m wide at 1m resolution. Once installed and calibrated, the system is designed to operate automatically producing maps in near real-time and making them available to on-board users via existing information systems. The resulting small-scale maps complement existing satellite based products as well as on-board observations. Development versions have temporarily been deployed in Antarctica on the RV Nathaniel B. Palmer in 2010 and in the Arctic on the USCGC Healy in 2011. A permanent system has been deployed during the summer of 2012 on the USCGC Healy. To make the system attractive to other ships of opportunity, design goals include using existing ship systems when practical, using low costs commercial-off-the-shelf components if additional hardware is necessary, automating the process to virtually eliminate adding to the workload of ships technicians and making the software components modular and flexible enough to allow more seamless integration with a ships particular IT system

Satellite Oceanography and Climate Change

International audienceSatellites are essential tools in the present monitoring of climate change as they provide frequent measurements of the Earth over decades with significantly high spatial resolution. Satellite measurements of sea surface temperature are a key component in the analyses of global warming and its effects. Altimeters and gravity missions such as GRACE are used to measure sea level rise at global and regional scales. A variety of satellite sensors (microwave and visible radiometers, scatterometers, SAR, gravity sensors, altimeters, etc.) are used for tracking the melting of sea ice and continental ice over the Polar Regions and Greenland. Satellite techniques are used to monitor large scale natural climate oscillations such as El Niño and the influence of atmospheric teleconexions such as NAO. The present issue is the first one of a series of issues updating our knowledge of the satellite-observed variability related to climate change. A short introduction to the topic is presented