scholarly journals Variability of NO<sub>x</sub> in the polar middle atmosphere from October 2003 to March 2004: vertical transport versus local production by energetic particles

2014 ◽  
Vol 14 (1) ◽  
pp. 1-29 ◽  
Author(s):  
M. Sinnhuber ◽  
B. Funke ◽  
T. von Clarmann ◽  
M. Lopez-Puertas ◽  
G. P. Stiller
Keyword(s):  
Geomagnetic Activity ◽  
Middle Atmosphere ◽  
Lower Thermosphere ◽  
Solar Proton ◽  
Electron Precipitation ◽  
Proton Event ◽  
Local Production ◽  
Altitude Range ◽  
Order Of Magnitude ◽  
The Impact

Abstract. We use NO, NO2 and CO from MIPAS/ENVISAT to investigate the impact of energetic particle precipitation onto the NOx budget from the stratosphere to the lower mesosphere in the period from October 2003 to March 2004, a time of high solar and geomagnetic activity. We find that in the winter hemisphere the indirect effect of auroral electron precipitation due to downwelling of upper mesospheric/lower thermospheric air into the stratosphere prevails. Its effect exceeds even the direct impact of the very large solar proton event in October/November 2003 by nearly one order of magnitude. Correlations of NOx and CO show that the unprecedented high NOx values observed in the Northern Hemisphere lower mesosphere and upper stratosphere in late January and early February are fully consistent with transport from the upper mesosphere/lower thermosphere and subsequent mixing at lower altitudes; an additional source of NOx due to local production by precipitating electrons at altitudes below 70 km as discussed in previous publications appears unlikely. In the polar summer Southern Hemisphere, we observed an enhanced variability of NO and NO2 on days with enhanced geomagnetic activity but they seem to indicate enhanced instrument noise rather than a direct increase due to electron precipitation. A direct effect of electron precipitation onto NOx can not be ruled out, but if any, it is lower than 3 ppb in the altitude range 40–56 km and lower than 6 ppb in the altitude range 56–70 km.

scholarly journals Variability of NO<sub>x</sub> in the polar middle atmosphere from October 2003 to March 2004: vertical transport vs. local production by energetic particles

2014 ◽  
Vol 14 (14) ◽  
pp. 7681-7692 ◽  
Author(s):  
M. Sinnhuber ◽  
B. Funke ◽  
T. von Clarmann ◽  
M. Lopez-Puertas ◽  
G. P. Stiller ◽  
...  
Keyword(s):  
Geomagnetic Activity ◽  
Middle Atmosphere ◽  
Lower Thermosphere ◽  
Solar Proton ◽  
Electron Precipitation ◽  
Proton Event ◽  
Local Production ◽  
Altitude Range ◽  
Order Of Magnitude ◽  
The Impact

Abstract. We use NO, NO2 and CO from MIPAS/ENVISAT to investigate the impact of energetic particle precipitation onto the NOx budget from the stratosphere to the lower mesosphere in the period from October 2003 to March 2004, a time of high solar and geomagnetic activity. We find that in the winter hemisphere the indirect effect of auroral electron precipitation due to downwelling of upper mesospheric/lower thermospheric air into the stratosphere prevails. Its effect exceeds even the direct impact of the very large solar proton event in October/November 2003 by nearly 1 order of magnitude. Correlations of NOx and CO show that the unprecedented high NOx values observed in the Northern Hemisphere lower mesosphere and upper stratosphere in late January and early February are fully consistent with transport from the upper mesosphere/lower thermosphere and subsequent mixing at lower altitudes. In the polar summer Southern Hemisphere, we observed an enhanced variability of NO and NO2 on days with enhanced geomagnetic activity, but this seems to indicate enhanced instrument noise rather than a direct increase due to electron precipitation. A direct effect of electron precipitation onto NOx can not be ruled out, but, if any, it is lower than 3 ppbv in the altitude range 40–56 km and lower than 6 ppbv in the altitude range 56–64 km. An additional significant source of NOx due to local production by precipitating electrons below 70 km exceeding several parts per billion as discussed in previous publications appears unlikely.

scholarly journals NO<sub>y</sub> production, ozone loss and changes in net radiative heating due to energetic particle precipitation in 2002–2010

2017 ◽  
Author(s):  
Miriam Sinnhuber ◽  
Uwe Berger ◽  
Bernd Funke ◽  
Holger Nieder ◽  
Thomas Reddmann ◽  
...  
Keyword(s):  
Energetic Particle ◽  
Solar Maximum ◽  
Lower Thermosphere ◽  
Solar Proton ◽  
Radiative Heating ◽  
Proton Event ◽  
Late Winter ◽  
Ozone Loss ◽  
Energetic Particle Precipitation ◽  
Ionization Rates

Abstract. We analyze the impact of energetic particle precipitation on the stratospheric nitrogen budget, ozone abundances and net radiative heating using results from three global chemistry-climate models considering solar protons and geomagnetic forcing due to auroral or radiation belt electrons. Two of the models cover the atmosphere up to the lower thermosphere, the source region of auroral NO production. Geomagnetic forcing in these models is included by prescribed ionization rates. One model reaches up to about 80 km, and geomagnetic forcing is included by applying an upper boundary condition of auroral NO mixing ratios parameterized as a function of geomagnetic activity. Despite the differences in the implementation of the particle effect, the resulting modeled NOy in the upper mesosphere agrees well between all three models, demonstrating that geomagnetic forcing is represented in a consistent way either by prescribing ionization rates or by prescribing NOy at the model top. Compared with observations of stratospheric and mesospheric NOy from the MIPAS instrument for the years 2002–2010, the model simulations reproduce the spatial pattern and temporal evolution well. However, after strong sudden stratospheric warmings, particle induced NOy is underestimated by both high-top models, and after the solar proton event in October 2003, NOy is overestimated by all three models. Model results indicate that the large solar proton event in October 2003 contributed about 1–2 Gmol (109 mol) NOy per hemisphere to the stratospheric NOy budget, while downwelling of auroral NOx from the upper mesosphere and lower thermosphere contributes up to 4 Gmol NOy. Accumulation over time leads to a constant particle-induced background of about 0.5–1 Gmol per hemisphere during solar minimum, and up to 2 Gmol per hemisphere during solar maximum. Related negative anomalies of ozone are predicted by the models nearly in every polar winter, ranging from 10–50 % during solar maximum to 2–10 % during solar minimum. Ozone loss continues throughout polar summer after strong solar proton events in the Southern hemisphere and after large sudden stratospheric warmings in the Northern hemisphere. During mid-winter, the ozone loss causes a reduction of the infrared radiative cooling, i.e., a positive change of the net radiative heating (effective warming), in agreement with analyses of geomagnetic forcing in stratospheric temperatures which show a warming in the late winter upper stratosphere. In late winter and spring, the sign of the net radiative heating change turns to negative (effective cooling). This spring-time cooling lasts well into summer and continues until the following autumn after large solar proton events in the Southern hemisphere, after sudden stratospheric warmings in the Northern hemisphere.

scholarly journals Middle atmospheric changes caused by the January and March 2012 solar proton events

2013 ◽  
Vol 13 (9) ◽  
pp. 23251-23293 ◽  
Author(s):  
C. H. Jackman ◽  
C. E. Randall ◽  
V. L. Harvey ◽  
S. Wang ◽  
E. L. Fleming ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Middle Atmosphere ◽  
Michelson Interferometer ◽  
Peroxy Radical ◽  
Solar Proton ◽  
Proton Event ◽  
Neutral Atmosphere ◽  
Cycle 24 ◽  
Atmospheric Changes ◽  
D Model

Abstract. The recent 23–30 January and 7–11 March 2012 solar proton event (SPE) periods were substantial and caused significant impacts on the middle atmosphere. These were the two largest SPE periods of solar cycle 24 so far. The highly energetic solar protons produced considerable ionization of the neutral atmosphere as well as HOx (H, OH, HO2) and NOx (N, NO, NO2). We compute a NOx production of 1.9 and 2.1 Gigamoles due to these SPE periods in January and March 2012, respectively, which places these SPE periods among the 12 largest in the past 50 yr. Aura Microwave Limb Sounder (MLS) observations of the peroxy radical, HO2, show significant enhancements of > 0.9 ppbv in the northern polar mesosphere as a result of these SPE periods. Both MLS measurements and Goddard Space Flight Center (GSFC) two-dimensional (2-D) model predictions indicated middle mesospheric ozone decreases of > 20% for several days in the northern polar region with maximum depletions > 60% over 1–2 days as a result of the HOx produced in both the January and March 2012 SPE periods. The SCISAT-1 Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE) and the Envisat Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instruments measured NO and NO2 (~ NOx), which indicated enhancements of over 20 ppbv in most of the northern polar mesosphere for several days as a result of these SPE periods. The GSFC 2-D model was used to predict the medium-term (~ months) influence and showed that the polar middle atmosphere ozone was most affected by these solar events in the Southern Hemisphere due to the increased downward motion in the fall and early winter. The downward transport moved the SPE-produced NOy to lower altitudes and led to predicted modest destruction of ozone (5–9%) in the upper stratosphere days to weeks after the March 2012 event. Total ozone reductions were predicted to be a maximum of 1% in 2012 due to these SPEs.

scholarly journals Multiradionuclide evidence for an extreme solar proton event around 2,610 B.P. (∼660 BC)

2019 ◽  
Vol 116 (13) ◽  
pp. 5961-5966 ◽  
Author(s):  
Paschal O’Hare ◽  
Florian Mekhaldi ◽  
Florian Adolphi ◽  
Grant Raisbeck ◽  
Ala Aldahan ◽  
...  
Keyword(s):  
Ice Core ◽  
Ice Cores ◽  
Solar Proton ◽  
Solar Proton Event ◽  
Proton Event ◽  
Production Rates ◽  
Cosmogenic Radionuclides ◽  
Solar Event ◽  
Carbon 14 ◽  
Order Of Magnitude

Recently, it has been confirmed that extreme solar proton events can lead to significantly increased atmospheric production rates of cosmogenic radionuclides. Evidence of such events is recorded in annually resolved natural archives, such as tree rings [carbon-14 (14C)] and ice cores [beryllium-10 (10Be), chlorine-36 (36Cl)]. Here, we show evidence for an extreme solar event around 2,610 years B.P. (∼660 BC) based on high-resolution10Be data from two Greenland ice cores. Our conclusions are supported by modeled14C production rates for the same period. Using existing36Cl ice core data in conjunction with10Be, we further show that this solar event was characterized by a very hard energy spectrum. These results indicate that the 2,610-years B.P. event was an order of magnitude stronger than any solar event recorded during the instrumental period and comparable with the solar proton event of AD 774/775, the largest solar event known to date. The results illustrate the importance of multiple ice core radionuclide measurements for the reliable identification of short-term production rate increases and the assessment of their origins.

scholarly journals <i>D</i> region ion-neutral coupled chemistry within a whole atmosphere chemistry-climate model

2016 ◽  
Author(s):  
Tamás Kovács ◽  
John M. C. Plane ◽  
Wuhu Feng ◽  
Tibor Nagy ◽  
Martyn P. Chipperfield ◽  
...  
Keyword(s):  
Climate Model ◽  
Negative Ions ◽  
Reaction Scheme ◽  
Solar Proton ◽  
Proton Event ◽  
Test Case ◽  
Neutral Species ◽  
Ion Molecule Reactions ◽  
D Region ◽  
The Impact

Abstract. This study presents a new ion-neutral chemical model coupled into the Whole Atmosphere Community Climate Model (WACCM). The ionospheric D region (altitudes ~ 50–90 km) chemistry is based on the Sodankylä Ion and Neutral Chemistry (SIC) model, a 1-dimensional model containing 306 ion-neutral and ionrecombination reactions of neutral species, positive and negative ions, and electrons. The SIC mechanism was reduced using the Simulation Error Minimization Connectivity Method (SEM-CM) to produce a reaction scheme of 181 ion-molecule reactions. This scheme describes the concentration profiles at altitudes between 20 km and 120 km of a set of major neutral species (HNO3, O3, H2O2, NO, NO2, HO2, OH, N2O5) and ions (O2+, O4+, NO+, NO+(H2O), O2+(H2O), H+(H2O), H+(H2O)2, H+(H2O)3, H+(H2O)4, O3−, NO2−, O−, O2, OH−, O2−(H2O), O2−(H2O)2, O4−, CO3−, CO3−(H2O), CO4−, HCO3−, NO2−, NO3−, NO3−(H2O), NO3(H2O)2, NO3−(HNO3), NO3−(HNO3)2, Cl−, ClO−), which agree with the full SIC mechanism within a 5 % tolerance. Four 3D model simulations were then performed, using the impact of the January 2005 Solar Proton Event (SPE) on D region HOx and NOx chemistry as a test case of four different model versions: the standard WACCM (no negative ions and a very limited set of positive ions); WACCM-SIC (standard WACCM with the full SIC chemistry of positive and negative ions); WACCM-D (standard WACCM with a heuristic reduction of the SIC chemistry, recently used to examine HNO3 formation following an SPE); and WACCM-rSIC (standard WACCM with a reduction of SIC chemistry using the SEM-CM Method). Standard WACCM misses the HNO3 enhancement during the SPE, while the full and reduced model versions predict significant NOx, HOx and HNO3 enhancements in the mesosphere during solar proton events. The SEM-CM reduction also identifies the important ion-molecule reactions that affect the partitioning of odd nitrogen (NOx), odd hydrogen (HOx), and O3 in the stratosphere and mesosphere.

Observational evidence of polar mesospheric ozone loss following substorm events

2021 ◽  
Author(s):  
Keeta Chapman-Smith ◽  
Annika Seppälä ◽  
Craig Rodger ◽  
Aaron Hendry
Keyword(s):  
Middle Atmosphere ◽  
Energetic Particles ◽  
Observational Evidence ◽  
Electron Precipitation ◽  
Data Sets ◽  
Ozone Loss ◽  
Mesospheric Ozone ◽  
Ozone Monitoring ◽  
The Impact

&lt;p&gt;Ozone in the polar middle atmosphere is known to be affected by charged energetic particles precipitating into the atmosphere from the magnetosphere. In recent years there has been increased interest in the sources and consequences of electron precipitation into the atmosphere. Substorms are an important source of electron precipitation. They occur hundreds of times a year and drive processes which cause electrons to be lost into our atmosphere. The electrons ionise neutrals in the atmosphere resulting in the production of HO&lt;sub&gt;x&lt;/sub&gt;&amp;#160;and NO&lt;sub&gt;x&lt;/sub&gt;, which catalytically destroy ozone. Simulations have examined substorm driven ozone loss and shown it is likely to be significant. However, this has not previously been verified from observations. Here we use polar mesospheric ozone observations from the Global Ozone Monitoring by Occultation of Stars (GOMOS) and Microwave Limb Sounder (MLS) instruments to investigate the impact of substorms. Using the superposed epoch technique we find consistent 10-20% reduction in mesospheric ozone in both data sets. This provides the first observational evidence that substorms are important to the ozone balance within the atmosphere.&lt;span&gt;&amp;#160;&lt;/span&gt;&lt;/p&gt;

scholarly journals Middle atmospheric changes caused by the January and March 2012 solar proton events

2014 ◽  
Vol 14 (2) ◽  
pp. 1025-1038 ◽  
Author(s):  
C. H. Jackman ◽  
C. E. Randall ◽  
V. L. Harvey ◽  
S. Wang ◽  
E. L. Fleming ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Middle Atmosphere ◽  
Transport Model ◽  
Michelson Interferometer ◽  
Three Dimensional ◽  
Peroxy Radical ◽  
Solar Proton ◽  
Proton Event ◽  
Neutral Atmosphere ◽  
D Model

Abstract. The recent 23–30 January and 7–11 March 2012 solar proton event (SPE) periods were substantial and caused significant impacts on the middle atmosphere. These were the two largest SPE periods of solar cycle 24 so far. The highly energetic solar protons produced considerable ionization of the neutral atmosphere as well as HOx (H, OH, HO2) and NOx (N, NO, NO2). We compute a NOx production of 1.9 and 2.1 Gigamoles due to these SPE periods in January and March 2012, respectively, which places these SPE periods among the 12 largest in the past 50 yr. Aura Microwave Limb Sounder (MLS) observations of the peroxy radical, HO2, show significant enhancements of > 0.9 ppbv in the northern polar mesosphere as a result of these SPE periods. Both MLS measurements and Goddard Space Flight Center (GSFC) two-dimensional (2-D) model predictions indicated middle mesospheric ozone decreases of > 20% for several days in the northern polar region with maximum depletions > 60% over 1–2 days as a result of the HOx produced in both the January and March 2012 SPE periods. The SCISAT-1 Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE) and the Envisat Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instruments measured NO and NO2 (~ NOx), which indicated enhancements of over 20 ppbv in most of the northern polar mesosphere for several days as a result of these SPE periods. The GSFC 2-D model and the Global Modeling Initiative three-dimensional chemistry and transport model were used to predict the medium-term (~ months) influence and showed that the polar middle atmospheric ozone was most affected by these solar events in the Southern Hemisphere due to the increased downward motion in the fall and early winter. The downward transport moved the SPE-produced NOy to lower altitudes and led to predicted modest destruction of ozone (5–13%) in the upper stratosphere days to weeks after the March 2012 event. Polar total ozone reductions were predicted to be a maximum of 1.5% in 2012 due to these SPEs.

scholarly journals Resonant scattering as a cause for the registration of scattering layers in the thermosphere and imaginary aerosol formations in the middle atmosphere

2019 ◽  
Vol 127 ◽  
pp. 01009
Author(s):  
Vasily Bychkov ◽  
Andrey Perezhogin ◽  
Ilya Seredkin
Keyword(s):  
Middle Atmosphere ◽  
Lower Thermosphere ◽  
Resonant Scattering ◽  
Resonance Scattering ◽  
Altitude Range ◽  
Entire Region ◽  
Scattering Signal ◽  
Additional Channel

The results of lidar and ionospheric observations from August to November 2017 are discussed. Resonance scattering was detected at wavelengths of 532.08 and 561.106 nm in the altitude range of 200-400 km and in the middle atmosphere. A possible mechanism for the formation of a resonant scattering signal on excited ions of the main gas components of the atmosphere is presented. The possibility of estimating the spectra of precipitated electrons is shown. It is shown that the complete profile of the backscattering signal can be restored in the region of 10–25 km using an additional channel for recording the attenuated signal separated from the main signal. Thus, it becomes possible to estimate the energies of electron flows in the entire region from the lower thermosphere to the stratosphere.

scholarly journals Reactive nitrogen (NO<sub><i>y</i></sub>) and ozone responses to energetic electron precipitation during Southern Hemisphere winter

2019 ◽  
Vol 19 (14) ◽  
pp. 9485-9494 ◽  
Author(s):  
Pavle Arsenovic ◽  
Alessandro Damiani ◽  
Eugene Rozanov ◽  
Bernd Funke ◽  
Andrea Stenke ◽  
...  
Keyword(s):  
Southern Hemisphere ◽  
Climate Model ◽  
Middle Atmosphere ◽  
Stratospheric Ozone ◽  
Energetic Electron ◽  
Polar Vortex ◽  
Solar Proton ◽  
Electron Precipitation ◽  
Reactive Nitrogen ◽  
High Electron

Abstract. Energetic particle precipitation (EPP) affects the chemistry of the polar middle atmosphere by producing reactive nitrogen (NOy) and hydrogen (HOx) species, which then catalytically destroy ozone. Recently, there have been major advances in constraining these particle impacts through a parametrization of NOy based on high-quality observations. Here we investigate the effects of low (auroral) and middle (radiation belt) energy range electrons, separately and in combination, on reactive nitrogen and hydrogen species as well as on ozone during Southern Hemisphere winters from 2002 to 2010 using the SOCOL3-MPIOM chemistry-climate model. Our results show that, in the absence of solar proton events, low-energy electrons produce the majority of NOy in the polar mesosphere and stratosphere. In the polar vortex, NOy subsides and affects ozone at lower altitudes, down to 10 hPa. Comparing a year with high electron precipitation with a quiescent period, we found large ozone depletion in the mesosphere; as the anomaly propagates downward, 15 % less ozone is found in the stratosphere during winter, which is confirmed by satellite observations. Only with both low- and middle-energy electrons does our model reproduce the observed stratospheric ozone anomaly.

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