Autonomous observations of energetic particle effects on the Antarctic atmosphere

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Recent research has suggested that energetic particles entering the Earth's atmosphere at the poles can lead to 5-10 K changes in the surface tempertaures in polar regions during the wintertime. This is thought to be as a result of chemical changes driven by energetic particles enering the Earth's atmosphere at high altitudes (50-90 km) affecting the radiation balance of the atmosphere as a whole. However the exact nature of the particles is unknown, and further analysis/confirmation of the effect on surface temperature variability is limited by this knowledge gap. We propose to fill this knowledge gap by deploying low-powered narrow band radio receivers south of the Antarctic Peninsula in order to monitor energetic particle precipitation coming from the radiation belts that surround the Earth. Only then will the study of the impact of the particles in driving atmospheric chemical changes be possible with any degree of certainty. Being able to site our experiments in the Antarctic is critical because: 1) the geomagnetic latitudes of the sites chosen for this project are associated with processes occuring at the heart of the outer radiation belt - allowing us to determine the maximum radiation belt particle influence on the atmosphere; 2) the effect of energetic particle precipitation on the experimental radiowave observations that we will make is enhanced over thick ice-sheet regions - this condition only occurs south of the Antarctic Peninsula at the geomagentic latitudes that are needed to make the best observations; 3) the region south of the Antarctic Peninsula is where most of the particle precipitation from the outer radiation belt will occur, because of the influence of the nearby South Atlantic Magnetic Anomaly in knocking the energetic particles out of their orbits and into the atmosphere. The data collected, analysed and interpreted by the project partners brought together by this proposal, will allow us to model the chemical changes in the Antarctic atmosphere due to energetic particle precipitation. As a result we will be able to determine the impact of complex radiation belt processes on the global atmosphere. Our Investigation of the effects on polar surface temperatures is part of international efforts to understand climate variability and the links to the upper atmosphere (e.g. the NERC Science Themes, the Climate and Weather of the Sun-Earth System programme, phase II, and the International Living with a Star programme - ILWS) . Our proposal is also timely in that there will be extensive supporting measurements made during the lifetime of our proposal by x-ray balloons funded by NASA, and by new NASA and CSA radiation belt satellites, all supported by the ILWS programme. Extensive collaboration between this proposal and the balloon/satellite mission scientific teams has been initiated and will continue throughout the project lifetime.