Influence of energetic particle precipitation and meteorology on NOx and ozone variability in the Arctic middle atmosphere

Lead Research Organisation: NERC British Antarctic Survey
Department Name: Science Programmes

Abstract

Predicting future climate change is intimately linked to understanding what is happening to the climate system in the present, and in the recent past. Studies in the Polar Regions provide vital clues in our understanding of global climate, and early indications of changes arising from the coupling of natural processes, such as variability in the amount of energy from the Sun reaching the Earth, and man-made factors. For example, the polar winter provides the extreme cold, dark conditions in the atmosphere which, combined with chemicals released from man-made chlorofluorocarbon (CFC) gases, has led to destruction of the ozone layer 18-25 km above the ground every spring-time since the 1980's. The Southern hemisphere ozone 'hole' is now linked to observed changes in surface temperature and sea-ice across Antarctica, decreased uptake of carbon dioxide by the Southern Ocean, and perturbations to the atmospheric circulation that can affect weather patterns as far away as the Northern hemisphere. Ozone loss over the Arctic is generally lower and much more variable, but there is increasing evidence that different meteorology in this region can lead to interactions between regions of the atmosphere from the ground to over 100 km up, on the edge of space. Recovery of the ozone layer is expected now that CFC's are banned by international protocols, but this may be delayed by other greenhouse gases we are releasing into the atmosphere and natural processes such as changes in the Sun's output. Although the total amount of energy as sunlight changes by a small amount (~0.1%) over the typical 11-year solar cycle, the energetic particles - electrons and protons - streaming from the Sun changes dramatically on timescales from hours to years. These particles are guided by the Earth's magnetic field and can enter the upper atmosphere, most intensely over the Polar Regions. A visible effect is the aurora, but the particles can significantly modify the chemistry of the atmosphere down to the ozone layer. Powerful solar storms can also damage satellites and disrupt electrical power networks. However the mechanisms by which energetic particles generated by the Sun enter the Earth's atmosphere, and the complex, interacting processes that affect stratospheric ozone are not well understood, which limits our ability to accurately predict future ozone changes and impacts on climate. We propose answering major unresolved questions about energetic particle effects on ozone by making observations of the middle atmosphere from the prestigious ALOMAR facility in northern Norway. This location, close to the Arctic Circle, is directly under the main region where energetic particles enter the atmosphere, making it ideal to observe the resulting effects. We will install a state-of-the-art microwave radiometer there alongside other equipment run by scientists from all round the world. By analysing the microwaves naturally emitted by the atmosphere high above us we can work out how much ozone there is 30-90 km above the ground as well as measuring chemicals produced in the atmosphere by energetic particles. We will make observations throughout a complete Arctic winter (2011/12) and interpret them with the help of data from orbiting spacecraft measuring the energetic particles entering the atmosphere. We will use the Arctic observations and computer-based models to better understand the impact of energetic particles on the atmosphere. The ultimate goal is to further understanding of the processes that lead to climate variability in the Polar Regions and globally - highly relevant for UK environmental science, the BAS programme, and collaborative research at an international level in which BAS plays a key role.
 
Description NERC Small Grant NE/I016767/1: Influence of energetic particle precipitation and meteorology on NOx and ozone variability in the Arctic middle atmosphere Key achievements • BAS microwave radiometer deployed at the Arctic LIDAR Observatory for Middle Atmosphere Research (ALOMAR, 69.3°N, 16.1°E, L = 6.4), Andøya, Norway during Arctic winter 2011/12. • Observations show no significant long-term (>5 days) increase in mesospheric nitric oxide (NO) above ALOMAR arising from the solar proton event (SPE) of 23-24 January 2012. • Electron and proton fluxes and count rates indicate that low-energy (>30 keV) auroral electron ionisation was a significant source of NO above 90 km whereas increased flux of higher energy (>300 keV) radiation-belt electrons occurred at lower geomagnetic latitudes (L = 4-6).
Exploitation Route The main users of this research are other scientists involved in middle atmosphere research. The Met Office was informed of the ongoing research and achievements during a 1-day visit by the PI. In addition various issues of radiometer design and calibration were discussed with members of the Met Office Atmospheric Radiation Research Group who are involved in microwave emissivity observations from the Facility for Airbourne Atmospheric Measurements (FAAM) aircraft and other platforms. The calibrated ozone data from the radiometer were provided to the Norwegian University of Science and Technology (NTNU)for analysis as part of an ongoing collaboration.
Sectors Environment

 
Description The observational data produced by this project are being shared with scientific colleagues to inform their development of atmospheric models, the aim being to accurately represent the chemical and dynamical impacts of space weather and energetic electron precipitation into the Arctic middle and upper atmosphere following geomagnetic storms.
First Year Of Impact 2012
Sector Environment
Impact Types Policy & public services

 
Title Middle atmospheric carbon monoxide above Troll station, Antarctica from February 2008 - January 2010: Version 2.0 (2013) 
Description Data-set associated with the retrieval of carbon monoxide (CO) volume mixing ratio profiles in the middle atmosphere above Troll station, Antarctica from February 2008 - January 2010: Version 2.0 (2013). The methodology and description of the data-sets are reported in Straub, C., P. J. Espy, R. E. Hibbins, and D. A. Newnham (2013), Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer, Earth Syst. Sci. Data, 5, 199-208, doi:10.5194/essd-5-199-2013. The CO observations were made using a ground-based passive millimetre-wave radiometer operated by the British Antarctic Survey (BAS). The Polar Data Centre (PDC) at BAS hold the data archive and have issued a Digital Object Identifier (doi) for the data-set. 
Type Of Material Database/Collection of data 
Year Produced 2013 
Provided To Others? Yes  
Impact No significant impact as yet. 
 
Title Middle atmospheric ozone above Troll Station, Antarctica, February 2008 - January 2010: Version 1.0 (2013). 
Description Data-set associated with the retrieval of ozone (O3) volume mixing ratio profiles in the middle atmosphere above Troll station, Antarctica from February 2008 - January 2010: Version 1.0 (2013). The methodology and description of the data-sets are reported in Daae, M., C. Straub, P. J. Espy, and D. A. Newnham (2014), Atmospheric ozone above Troll station, Antarctica observed by a ground based microwave radiometer, Earth Syst. Sci. Data, 6, 105-115, doi:10.5194/essd-6-105-2014. The CO observations were made using a ground-based passive millimetre-wave radiometer operated by the British Antarctic Survey (BAS). The Polar Data Centre (PDC) at BAS hold the data archive and have issued a Digital Object Identifier (doi) for the data-set. 
Type Of Material Database/Collection of data 
Year Produced 2013 
Provided To Others? Yes  
Impact The ozone data-sets have so far been used in scientific analyses resulting in the following three journal publications: Daae, M., P. J. Espy, H. N. Nesse Tyssøy, D. A. Newnham, J. Stadsnes, and F. Søraas (2012), The effect of energetic electron precipitation on middle mesospheric night-time ozone during and after a moderate geomagnetic storm, Geophys. Res. Lett., 39, L21811, doi:10.1029/2012GL053787. Demissie, T. D., K. Hosokawa, N. Kleinknecht, P. J. Espy, R. Hibbins (2013), Planetary wave oscillations observed in ozone and PMSE data from Antarctica, J. Atmos. Solar-Terrestrial Phys. 105-106, 207-213, doi:10.1016/j.jastp.2013.10.008. Demissie, T. D., N. H. Kleinknecht, R. E. Hibbins, P. J. Espy, and C. Straub (2013), Quasi-16-day period oscillations observed in middle atmospheric ozone and temperature in Antarctica, Ann. Geophys., 31, 1279-1284, doi:10.5194/angeo-31-1279-2013. 
 
Description Collaboration with MIT Haystack Observatory 
Organisation Massachusetts Institute of Technology
Country United States 
Sector Academic/University 
PI Contribution The PI visited MIT Haystack Observatory, USA in August 2017 to discuss the NERC STO3RM project with Professor Alan Rogers, the original developer of low-cost mesospheric ozone spectrometers based on commercial satellite TV receiver technologies. He shared information on the simulation study results and details of the supplier of 13.44 GHz receivers that can potentially be used to make remote sensing measurements of hydroxyl (OH) in the middle atmosphere. The PI also gave a general talk at the Observatory.
Collaborator Contribution Professor Alan Rogers provided technical advice on the practical construction and operation of satellite-TV based ozone spectrometers. He shared the computer code used to process observational data from such instruments into atmospheric data.
Impact Procurement of 13.44 GHz receiver to investigate potential hydroxyl (OH) observations by MIT Haystack Observatory, using information provided by PI.
Start Year 2017