Jan Maik Wissing

Universität Osnabrück | UOS · Numerical Physics

Precipitating auroral and radiation belt electrons are considered to play an important part in the natural forcing of the middle atmosphere with a possible impact on the climate system. Recent studies suggest that this forcing is underestimated in current chemistry‐climate models. The HEPPA III intercomparison experiment is a collective effort to a...

Precipitating auroral and radiation belt electrons are considered an important part of the natural forcing of the climate system. Recent studies suggest that this forcing is underestimated in current chemistry‐climate models. The High Energy Particle Precipitation in the Atmosphere III intercomparison experiment is a collective effort to address th...

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 therm...

The 3-dimensional global chemistry and transport model (3dCTM) was used to investigate NO, OH, and O3 from January 2002 to May 2010 between 60 km and 133 km. Their daytime and nighttime mean zonal means (55°-75° geomagnetic latitude) were analyzed with respect to short-term variations associated with particle precipitation. The corresponding ioniza...

We quantify the effects of combined precipitating solar protons and magnetospheric electrons on nighttime odd hydrogen density enhancements during two solar energetic particle (SEP) events accompanied by strong geomagnetic storms. We perform detailed modeling of ionization rates for 7-17 November 2004 and 20-30 August 2005 intervals with improved v...

We investigate the influence of Middle Range Energy Electrons (MEE; typically 30-300. keV) precipitation on the atmosphere using the SOCOL3-MPIOM chemistry-climate model with coupled ocean. Model simulations cover the 2002-2010 period for which ionization rates from the AIMOS dataset and atmospheric composition observations from MIPAS are available...

Particle precipitation causes atmospheric ionization. Modeled ionization rates are widely used in atmospheric chemistry/climate simulations of the upper atmosphere. As ionization rates are based on particle measurements some assumptions concerning the energy spectrum are required. While detectors measure particles binned into certain energy ranges...

Understanding the altitude distribution of particle precipitation forcing is vital for the assessment of its atmospheric and climate impacts. However, the proportion of electron and proton forcing around the mesopause region during solar proton events is not always clear due to uncertainties in satellite-based flux observations. Here we use electro...

We present altitude-dependent lifetimes of NOx, determined with MIPAS/ENVISAT (the Michelson Interferometer for Passive Atmospheric Sounding/the European Environment Satellite), for the Southern polar region after the solar proton event in October-November 2003. Between 50° S and 90° S and decreasing in altitude they range from about two days at 64...

Solar eruptions and geomagnetic storms can produce fluxes of high-energy protons and elec-trons, so-called Solar Energetic Particle Events, which can enter the Earth’s atmosphere espe-cially in polar regions. These particle fluxes primarily cause ionisation and excitation in the upper atmosphere, and thereby the production of HOx and NOx species, w...

We present altitude dependent lifetimes of NOx, determined with MIPAS/ENVISAT, for the southern polar region after the solar proton event in October–November 2003. Varying in latitude and decreasing in altitude they range from about two days at 64 km to about 20 days at 44 km. The lifetimes are controlled by transport, mixing and photolysis. We inf...

The response of noctilucent clouds to the solar particle event in January 2005 is investigated by means of icy particle and ion chemistry simulations. It is shown that the decreasing occurrence rate of noctilucent clouds derived from measurements of the SCIAMACHY/Envisat instrument can be reproduced by one-dimensional model simulations if temperatu...

The response of noctilucent clouds to the solar particle event in January 2005 is investigated by means of icy particle and ion chemistry simulations. It is shown that the decreasing occurrence rate of noctilucent clouds derived from measurements of the SCIAMACHY/Envisat instrument can be reproduced by one-dimensional model simulations if temperatu...

We present model simulations with the 3D model KASIMA for the Arctic winter 2008/2009. Despite low solar and geomagnetic activity, in this winter one of the strongest NOx intrusions from the lower thermosphere to the mesosphere and upper stratosphere has been observed after the stratospheric warming in early 2009. It seems still to be unclear how m...

We have compared composition changes of NO, NO₂, H₂O₂, O₃, N₂O, HNO₃, N₂O₅, HNO₄, ClO, HOCl, and ClONO₂ as observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat in the aftermath of the "Halloween" sola...

We have compared composition changes of NO, NO₂, H₂O₂, O₃, N₂O, HNO₃, N₂O₅, HNO₄, ClO, HOCl, and ClONO₂ as observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat in the aftermath of the "Halloween" sola...

Ionization of the atmosphere due to precipitating solar energetic particles as well as magnetospheric particles is a major source of thermospheric electron density. In this paper we evaluate numerical simulations of the 3-D spatial and temporal electron densities produced by these particle populations through a comparison with incoherent scatter ra...

The interannual variation of NOx throughout the year is investigated for the period 1991–2005 at middle to high latitudes using Halogen Occultation Experiment (HALOE) on UARS measurements. We find a clear correlation of NOx between 80 and 130 km with the auroral electrojet index in both hemispheres, which is fairly independent of season, indicating...

Solar particle events (SPEs) are well known sources of chemical perturbations in the middle atmosphere. A well-understood effect is the release of reactive NOx and HOx, and the subsequent destruction of ozone. Satellite measurements (HALOE, MIPAS, AURA-MLS) have shown that there is also chlorine activation in the stratosphere and mesosphere, and an...

Observations of Polar Mesosphere Summer Echoes (PMSE) obtained by the ALWIN VHF radar, located in Andenes, Norway (69°N, 16°E) and by the Resolute Bay VHF radar, located in Nunavut, Canada (75°N, 95°W), are characterized by differences in occurrence rate and PMSE strengths, with generally lower levels at Resolute Bay. Even though both radars are we...

The precipitation of solar energetic particles, protons as well as electrons, at high latitudes is commonly assumed to be homogeneous across both polar caps. Using Low-Earth Orbit POES (Polar Orbiting Environmental Satellites) we determine particle penetration ratios into the polar atmosphere for protons ranging from about 0.1MeV to 500MeV and for...

Precipitating solar protons contribute to ozone depletion in the atmosphere; α particles and electrons also precipitate during solar energetic particle (SEP) events. If the SEP is accompanied by a shock, then magnetospheric particles can also be injected into the atmosphere as the shock hits the magnetosphere. Both particle species in both particle...

Solar particle events (SPEs) are well-known sources of distinct ion-chemical disturbances in the Earth's polar mesosphere, and if a SPE occurs during polar summer, mutual interactions be-tween the disturbed ion chemistry and noctilucent clouds (NLCs) are expected. The increasing ionisation rates during SPEs lead to short-term enhancements of positi...

Relativistic electrons precipitating from radiation belts and solar protons can penetrate below 100 km into the polar atmosphere sometimes reaching the stratospheric levels wasting its energy and causing the ionization. It leads to additional production of NOx and HOx chemical com-pounds which destroy ozone in the chemical catalytic cycles. One of...

It is well established that solar particle events (SPEs) are sources of significant chemical dis-turbances in the Earth's polar atmosphere. The observed SPE effects on nitrogen, hydrogen and oxygen compounds have been investigated in some detail in recent years, and they can be reproduced by atmospheric models using basic parametrizations for NOx a...

Energetic particles transform photochemical system in polar regions during geomagnetic storms and solar proton events (SPE) due to the additional production of NOx and HOx chemical compounds. Then it leads to ozone destruction in the stratosphere and mesosphere and to the induced changes in temperature and dynamics. Such dynamical response after SP...

1] We present a 3-D numerical model of atmospheric ionization due to precipitating particles with high spatial resolution. The Atmospheric Ionization Model Osnabrück (AIMOS) consists of two parts: a GEANT4-based Monte Carlo simulation and a sorting algorithm to assign observations from two polar-orbiting satellites to horizontal precipitation cells...

It is well established that solar proton events (SPEs) are sources of distinct chemical disturbances in the Earth’s polar atmosphere. While the observed SPE caused production of NOx, and the subsequent destruction of ozone can be reproduces quite well by atmospheric models using basic parametrizations for NOx and HOx release as a function of the pa...

Precipitating electrons, protons, and alpha particles enter the Earth's atmosphere at high latitudes caused by solar and magnetospheric activity. They can lead to ionization, dissociation, dissociative ionization and excitation of molecules and atoms of the upper and middle atmosphere. These particle-induced interactions result in the production of...

The detailed study of the precipitation of magnetospheric particles into the atmosphere is complicated by the rather complex spatial configuration of the precipitation region and its variability with geomagnetic activity. In this paper we will introduce polar oval coordinates and apply them to POES observations of 30 keV to 2.5 MeV electrons and co...

POES MEPED TED together with data from ACE and geomagnetic indices indicate two sources for high latitude energetic particle precipitation magnetospheric particles and solar particles Important results include that variation of precipitation patterns depends on many factors begin itemize item a Geomagnetic acitvity and interplanetary particle flux...

Atmospheric ozone chemistry is influenced by solar energetic particles Visible depletion of ozone has been shown to follow solar energetic particle SEP events A basic assumption for chemistry models is that the flux signal over the polar caps corresponds to the interplanetary flux possibly varying with the interplanetary magnetic field and that par...