Articles | Volume 33, issue 5
https://doi.org/10.5194/angeo-33-561-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/angeo-33-561-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Regular paper
| 
26 May 2015
Regular paper |
| 26 May 2015
Ionization and NO production in the polar mesosphere during high-speed solar wind streams: model validation and comparison with NO enhancements observed by Odin-SMR
S. Kirkwood
CORRESPONDING AUTHOR
Polar Atmospheric Research, Swedish Institute of Space Physics, P.O. Box 812, 98128 Kiruna, Sweden
A. Osepian
Polar Geophysical Institute, Halturina 15, 183 023 Murmansk, Russia
E. Belova
Polar Atmospheric Research, Swedish Institute of Space Physics, P.O. Box 812, 98128 Kiruna, Sweden
J. Urban
Department of Radio and Space Science, Chalmers University of Technology, Hörsalsvägen 11, 412 96 Gothenburg, Sweden
deceased
Department of Radio and Space Science, Chalmers University of Technology, Hörsalsvägen 11, 412 96 Gothenburg, Sweden
A. K. Sinha
Indian Institute of Geomagnetism, 410218 Navi Mumbai, India
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We validate horizontal wind measurements at altitudes of 0.5–14 km made with atmospheric radars: ESRAD located near Kiruna in the Swedish Arctic and MARA at the Indian research station Maitri in Antarctica, by comparison with radiosondes, the regional model HARMONIE-AROME and the ECMWF ERA5 reanalysis. Good agreement was found in general, and radar bias and uncertainty were estimated. These radars are planned to be used for validation of winds measured by lidar by the ESA satellite Aeolus.
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In December 1991, precipitation on the Glorieuses and Mayotte was more than 3 times the climatological mean and mean sunshine duration was less than 1.5h per day. The most likely explanation was low values of the Madden-Julian Oscillation index, which favours high rainfall. El Niño, eastward quasi-biennial oscillation and high solar activity may also have had an indirect effect. No effect of the Pinatubo volcanic eruption is indicated as the precipitation anomalies are only local.
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It is well known that occasional eruptions of very high energy protons from the Sun directly impact the middle atmosphere in the polar regions. This paper shows that much more frequent high-speed streams in the plasma wind from the Sun can also modify the same parts of the atmosphere. Their effects are made "visible" by strong enhancement of radar echoes in polar winter and were found to affect half of the days when observations were made at Troll, Antarctica, in 2012 and 2013.
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Gunter Stober, Sharon L. Vadas, Erich Becker, Alan Liu, Alexander Kozlovsky, Diego Janches, Zishun Qiao, Witali Krochin, Guochun Shi, Wen Yi, Jie Zeng, Peter Brown, Denis Vida, Neil Hindley, Christoph Jacobi, Damian Murphy, Ricardo Buriti, Vania Andrioli, Paulo Batista, John Marino, Scott Palo, Denise Thorsen, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Johan Kero, Evgenia Belova, Nicholas Mitchell, Tracy Moffat-Griffin, and Na Li
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On 15 January 2022, the Hunga Tonga-Hunga Ha‘apai volcano exploded in a vigorous eruption, causing many atmospheric phenomena reaching from the surface up to space. In this study, we investigate how the mesospheric winds were affected by the volcanogenic gravity waves and estimated their propagation direction and speed. The interplay between model and observations permits us to gain new insights into the vertical coupling through atmospheric gravity waves.
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Gunter Stober, Alexander Kozlovsky, Alan Liu, Zishun Qiao, Masaki Tsutsumi, Chris Hall, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, Patrick J. Espy, Robert E. Hibbins, and Nicholas Mitchell
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Wind observations at the edge to space, 70–110 km altitude, are challenging. Meteor radars have become a widely used instrument to obtain mean wind profiles above an instrument for these heights. We describe an advanced mathematical concept and present a tomographic analysis using several meteor radars located in Finland, Sweden and Norway, as well as Chile, to derive the three-dimensional flow field. We show an example of a gravity wave decelerating the mean flow.
Gunter Stober, Ales Kuchar, Dimitry Pokhotelov, Huixin Liu, Han-Li Liu, Hauke Schmidt, Christoph Jacobi, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, and Nicholas Mitchell
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Little is known about the climate change of wind systems in the mesosphere and lower thermosphere at the edge of space at altitudes from 70–110 km. Meteor radars represent a well-accepted remote sensing technique to measure winds at these altitudes. Here we present a state-of-the-art climatological interhemispheric comparison using continuous and long-lasting observations from worldwide distributed meteor radars from the Arctic to the Antarctic and sophisticated general circulation models.
Francesco Grieco, Kristell Pérot, Donal Murtagh, Patrick Eriksson, Bengt Rydberg, Michael Kiefer, Maya Garcia-Comas, Alyn Lambert, and Kaley A. Walker
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Evgenia Belova, Sheila Kirkwood, Peter Voelger, Sourav Chatterjee, Karathazhiyath Satheesan, Susanna Hagelin, Magnus Lindskog, and Heiner Körnich
Atmos. Meas. Tech., 14, 5415–5428, https://doi.org/10.5194/amt-14-5415-2021, https://doi.org/10.5194/amt-14-5415-2021, 2021
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Wind measurements from two radars (ESRAD in Arctic Sweden and MARA at the Indian Antarctic station Maitri) are compared with lidar winds from the ESA satellite Aeolus, for July–December 2019. The aim is to check if Aeolus data processing is adequate for the sunlit conditions of polar summer. Agreement is generally good with bias in Aeolus winds < 1 m/s in most circumstances. The exception is a large bias (7 m/s) when the satellite has crossed a sunlit Antarctic ice cap before passing MARA.
Michaela I. Hegglin, Susann Tegtmeier, John Anderson, Adam E. Bourassa, Samuel Brohede, Doug Degenstein, Lucien Froidevaux, Bernd Funke, John Gille, Yasuko Kasai, Erkki T. Kyrölä, Jerry Lumpe, Donal Murtagh, Jessica L. Neu, Kristell Pérot, Ellis E. Remsberg, Alexei Rozanov, Matthew Toohey, Joachim Urban, Thomas von Clarmann, Kaley A. Walker, Hsiang-Jui Wang, Carlo Arosio, Robert Damadeo, Ryan A. Fuller, Gretchen Lingenfelser, Christopher McLinden, Diane Pendlebury, Chris Roth, Niall J. Ryan, Christopher Sioris, Lesley Smith, and Katja Weigel
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An overview of the SPARC Data Initiative is presented, to date the most comprehensive assessment of stratospheric composition measurements spanning 1979–2018. Measurements of 26 chemical constituents obtained from an international suite of space-based limb sounders were compiled into vertically resolved, zonal monthly mean time series. The quality and consistency of these gridded datasets are then evaluated using a climatological validation approach and a range of diagnostics.
Evgenia Belova, Peter Voelger, Sheila Kirkwood, Susanna Hagelin, Magnus Lindskog, Heiner Körnich, Sourav Chatterjee, and Karathazhiyath Satheesan
Atmos. Meas. Tech., 14, 2813–2825, https://doi.org/10.5194/amt-14-2813-2021, https://doi.org/10.5194/amt-14-2813-2021, 2021
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We validate horizontal wind measurements at altitudes of 0.5–14 km made with atmospheric radars: ESRAD located near Kiruna in the Swedish Arctic and MARA at the Indian research station Maitri in Antarctica, by comparison with radiosondes, the regional model HARMONIE-AROME and the ECMWF ERA5 reanalysis. Good agreement was found in general, and radar bias and uncertainty were estimated. These radars are planned to be used for validation of winds measured by lidar by the ESA satellite Aeolus.
Anqi Li, Chris Z. Roth, Kristell Pérot, Ole Martin Christensen, Adam Bourassa, Doug A. Degenstein, and Donal P. Murtagh
Atmos. Meas. Tech., 13, 6215–6236, https://doi.org/10.5194/amt-13-6215-2020, https://doi.org/10.5194/amt-13-6215-2020, 2020
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The OSIRIS IR imager, one of the instruments on the Odin satellite, routinely measures the oxygen airglow at 1.27 μm. In this study, we primarily focus on the steps done for retrieving the calibrated IRA band limb radiance, the volume emission rate of O2(a1∆g) and finally the ozone number density. Specifically, we use a novel approach to address the issue of the measurements that were made close to the local sunrise, where the O2(a1∆g) diverges from the equilibrium state.
Francesco Grieco, Kristell Pérot, Donal Murtagh, Patrick Eriksson, Peter Forkman, Bengt Rydberg, Bernd Funke, Kaley A. Walker, and Hugh C. Pumphrey
Atmos. Meas. Tech., 13, 5013–5031, https://doi.org/10.5194/amt-13-5013-2020, https://doi.org/10.5194/amt-13-5013-2020, 2020
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We present a unique – by time extension and geographical coverage – dataset of satellite observations of carbon monoxide (CO) in the mesosphere which will allow us to study dynamical processes, since CO is a very good tracer of circulation in the mesosphere. Previously, the dataset was unusable due to instrumental artefacts that affected the measurements. We identify the cause of the artefacts, eliminate them and prove the quality of the results by comparing with other instrument measurements.
Joonas Kiviranta, Kristell Pérot, Patrick Eriksson, and Donal Murtagh
Atmos. Chem. Phys., 18, 13393–13410, https://doi.org/10.5194/acp-18-13393-2018, https://doi.org/10.5194/acp-18-13393-2018, 2018
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This paper investigates how the activity of the Sun affects the amount of nitric oxide (NO) in the upper atmosphere. If NO descends lower down in the atmosphere, it can destroy ozone. We analyze satellite measurements of NO to create a model that can simulate the amount of NO at any given time. This model can indeed simulate NO with reasonable accuracy and it can potentially be used as an input for a larger model of the atmosphere that attempts to explain how the Sun affects our atmosphere.
Philippe Baron, Donal Murtagh, Patrick Eriksson, Jana Mendrok, Satoshi Ochiai, Kristell Pérot, Hideo Sagawa, and Makoto Suzuki
Atmos. Meas. Tech., 11, 4545–4566, https://doi.org/10.5194/amt-11-4545-2018, https://doi.org/10.5194/amt-11-4545-2018, 2018
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This paper investigates with computer simulations the measurement performances of the satellite Stratospheric Inferred Winds (SIW) in the altitude range 10–90 km. SIW is a Swedish mission that will be launched close to 2022. It is intended to fill the current altitude gap between 30 and 70 km in wind measurements and to pursue the monitoring of temperature and key stratospheric constituents for better understanding climate change effects.
Bernd Funke, William Ball, Stefan Bender, Angela Gardini, V. Lynn Harvey, Alyn Lambert, Manuel López-Puertas, Daniel R. Marsh, Katharina Meraner, Holger Nieder, Sanna-Mari Päivärinta, Kristell Pérot, Cora E. Randall, Thomas Reddmann, Eugene Rozanov, Hauke Schmidt, Annika Seppälä, Miriam Sinnhuber, Timofei Sukhodolov, Gabriele P. Stiller, Natalia D. Tsvetkova, Pekka T. Verronen, Stefan Versick, Thomas von Clarmann, Kaley A. Walker, and Vladimir Yushkov
Atmos. Chem. Phys., 17, 3573–3604, https://doi.org/10.5194/acp-17-3573-2017, https://doi.org/10.5194/acp-17-3573-2017, 2017
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Simulations from eight atmospheric models have been compared to tracer and temperature observations from seven satellite instruments in order to evaluate the energetic particle indirect effect (EPP IE) during the perturbed northern hemispheric (NH) winter 2008/2009. Models are capable to reproduce the EPP IE in dynamically and geomagnetically quiescent NH winter conditions. The results emphasize the need for model improvements in the dynamical representation of elevated stratopause events.
Kazutoshi Sagi, Kristell Pérot, Donal Murtagh, and Yvan Orsolini
Atmos. Chem. Phys., 17, 1791–1803, https://doi.org/10.5194/acp-17-1791-2017, https://doi.org/10.5194/acp-17-1791-2017, 2017
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We assess and quantify the ozone loss driven by NOx, triggered by stratospheric warmings and the halogens-induced ozone loss, using data assimilation results over a decade.
To illustrate the difference between halogen-induced loss and NOx-induced loss, we compared a relatively cold and stable winter (2010/2011) with a composite calculation of four winters (2003/2004, 2005/2006, 2008/2009 and 2012/2013) which were all affected by a major mid-winter sudden stratospheric warming event.
Christine Smith-Johnsen, Yvan Orsolini, Frode Stordal, Varavut Limpasuvan, and Kristell Pérot
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-758, https://doi.org/10.5194/acp-2016-758, 2016
Preprint withdrawn
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Mesospheric ozone enhancements during sudden stratospheric warmings in the northern hemisphere have been reported in the literature. In the southern hemisphere, only one warming event has occurred, and this paper is the first to explain the mesospheric ozone enhancement during this event in 2002, using both a whole atmosphere chemistry climate model and satellite observations from GOMOS.
S. Bender, M. Sinnhuber, T. von Clarmann, G. Stiller, B. Funke, M. López-Puertas, J. Urban, K. Pérot, K. A. Walker, and J. P. Burrows
Atmos. Meas. Tech., 8, 4171–4195, https://doi.org/10.5194/amt-8-4171-2015, https://doi.org/10.5194/amt-8-4171-2015, 2015
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We compare the nitric oxide (NO) daily zonal mean number density data sets in the mesosphere and lower thermosphere (MLT, 60km to 150km) from four instruments: ACE-FTS (2004--2010), MIPAS (2005--2012), SCIAMACHY (2008--2012), and SMR (2003--2012). We find that these data sets from different instruments consistently constrain NO in the MLT. Thus, they offer reliable forcing inputs for climate and chemistry climate models as an initial step to include solar and geomagnetic activity.
A. Réchou and S. Kirkwood
Ann. Geophys., 33, 789–804, https://doi.org/10.5194/angeo-33-789-2015, https://doi.org/10.5194/angeo-33-789-2015, 2015
Short summary
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In December 1991, precipitation on the Glorieuses and Mayotte was more than 3 times the climatological mean and mean sunshine duration was less than 1.5h per day. The most likely explanation was low values of the Madden-Julian Oscillation index, which favours high rainfall. El Niño, eastward quasi-biennial oscillation and high solar activity may also have had an indirect effect. No effect of the Pinatubo volcanic eruption is indicated as the precipitation anomalies are only local.
S. Kirkwood, A. Osepian, E. Belova, and Y.-S. Lee
Ann. Geophys., 33, 609–622, https://doi.org/10.5194/angeo-33-609-2015, https://doi.org/10.5194/angeo-33-609-2015, 2015
Short summary
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It is well known that occasional eruptions of very high energy protons from the Sun directly impact the middle atmosphere in the polar regions. This paper shows that much more frequent high-speed streams in the plasma wind from the Sun can also modify the same parts of the atmosphere. Their effects are made "visible" by strong enhancement of radar echoes in polar winter and were found to affect half of the days when observations were made at Troll, Antarctica, in 2012 and 2013.
T. Fytterer, M. G. Mlynczak, H. Nieder, K. Pérot, M. Sinnhuber, G. Stiller, and J. Urban
Atmos. Chem. Phys., 15, 3327–3338, https://doi.org/10.5194/acp-15-3327-2015, https://doi.org/10.5194/acp-15-3327-2015, 2015
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Energetic particles from the sun produce NOx (=N+NO+NO2) in the mesosphere/lower thermosphere. The NOx can be transported downward in the stratosphere during polar winter where NOx eventually depletes O3. This entire chain is the so-called energetic particle precipitation (EPP) indirect effect.
Here we show downward propagating negative stratospheric O3 anomalies during Antarctic polar winter. The O3 anomalies are caused by geomagnetic activity and show strong hints of the EPP indirect effect.
K. Pérot, J. Urban, and D. P. Murtagh
Atmos. Chem. Phys., 14, 8009–8015, https://doi.org/10.5194/acp-14-8009-2014, https://doi.org/10.5194/acp-14-8009-2014, 2014
A. Réchou, S. Kirkwood, J. Arnault, and P. Dalin
Atmos. Chem. Phys., 14, 6785–6799, https://doi.org/10.5194/acp-14-6785-2014, https://doi.org/10.5194/acp-14-6785-2014, 2014
V. Barabash, A. Osepian, and P. Dalin
Ann. Geophys., 32, 207–222, https://doi.org/10.5194/angeo-32-207-2014, https://doi.org/10.5194/angeo-32-207-2014, 2014
E. Belova, S. Kirkwood, and T. Sergienko
Ann. Geophys., 31, 1177–1190, https://doi.org/10.5194/angeo-31-1177-2013, https://doi.org/10.5194/angeo-31-1177-2013, 2013
M. Mihalikova and S. Kirkwood
Ann. Geophys., 31, 591–598, https://doi.org/10.5194/angeo-31-591-2013, https://doi.org/10.5194/angeo-31-591-2013, 2013
S. Kirkwood, E. Belova, P. Dalin, M. Mihalikova, D. Mikhaylova, D. Murtagh, H. Nilsson, K. Satheesan, J. Urban, and I. Wolf
Ann. Geophys., 31, 333–347, https://doi.org/10.5194/angeo-31-333-2013, https://doi.org/10.5194/angeo-31-333-2013, 2013
A. Réchou, J. Arnault, P. Dalin, and S. Kirkwood
Ann. Geophys., 31, 239–250, https://doi.org/10.5194/angeo-31-239-2013, https://doi.org/10.5194/angeo-31-239-2013, 2013
Short summary
High-speed streams of particles from the Sun can cause high-energy electrons to be precipitated into the Earth's middle atmosphere at polar latitudes. The paper develops and tests a model for how these particles can change the amount of a trace gas, nitric oxide, which has the potential to destroy stratospheric ozone. Model calculations agree well with observations by the Odin satellite of increased nitric oxide over Antarctica associated with high-speed solar wind streams.
High-speed streams of particles from the Sun can cause high-energy electrons to be precipitated...
