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Der vorliegende Beitrag gibt einen kurzen Überblick über die wichtigsten Wendepunkte in der zwölf-jährigen Geschichte der Gruppe „Islamischer Staat“ (IS) im Irak. Die andauernden Konflikte in Syrien und Irak haben, neben ihren unmittelbaren humanitären Folgen für die Zivilbevölkerung, auch Auswirkungen auf die globale Ideologie des Dschihadismus und beeinflussen somit indirekt auch andere regionale Konflikte.
Von 2003 bis 2014 war der IS eine von vielen regionalen Gruppen weltweit, die unter der nominellen Führung von al-Qaida am globalen Dschihad teilnahmen. Heute setzt der IS eigene Machtansprüche in Syrien und Irak in direkter Konfrontation mit dem syrischen Ableger der Al-Qaida(Jabhat An-Nusra) durch. Infolge dieser Auseinandersetzung gab Ayman az-Zawahiri im Februar 2014 öffentlich bekannt, dass al-Qaida den IS aus ihrer Organisation ausschließt.
Nicht zuletzt durch diesen Ausschluss war der IS unter der Führung von Abu Bakr al-Baghdadi genötigt den eigenen Führungsanspruch in der Region durch die Ausrufung eines Kalifates nachdrücklich geltend zu machen.
Dies war allerdings keine spontane Entscheidung, denn die Errichtung eines Kalifats war ein Plan, den Baghdadis Gruppe seit vielen Jahren mit großem Aufwand verfolgte.
Durch das Zerwürfnis zwischen dem IS und der afghanisch-pakistanischen al-Qaida teilt sich die globale dschihadistische Bewegung nun in zwei Einflussreiche Einheiten.
Salafismus ist eine totalitäre Variante des Islam, die im Gegensatz zu Demokratie, den Menschenrechten und der Idee der Geschlechtergerechtigkeit steht. Er verbindet eine in die Vergangenheit projizierte Utopie mit modernen Elementen der Pop-Kultur und ist in vielen Ländern – u.a. in Deutschland - die am schnellsten wachsende Jugendbewegung.
Jihadismus ist die gewalttätige Spielart des Salafismus. Vereinfacht lässt sich sagen, dass alle Jihadisten Salafisten sind, aber nur wenige Salafisten jemals Jihadisten werden.
Afghanistans ehemalige Mudschahedin haben es geschafft: Kritik an „heiligen Kriegern“, wie sie sich nun nennen, ist gleichzeitig Kritik am Islam, und das ist brandgefährlich in ihrem Land. Manch ein Kriegsverbrecher nutzt das Islam- Argument, um sich über das staatliche Gesetz zu stellen und damit unangreifbar zu machen. Säkulare Gruppierungen, die in der urbanen Bevölkerung weiter bestehen, würden es heute nicht mehr wagen, sich öffentlich so zu bezeichnen. In Regierung, Justiz und Gesellschaft ist der Druck, sich zum Islam zu bekennen, groß. Eine zuweilen absurd anmutende Konkurrenz darüber, wer am ‚islamischten‘ ist, führt zu immensem Druck auf Medien und Zivilgesellschaft, insbesondere auf Frauenrechtsgruppen, sich innerhalb des Islams zu positionieren und sich abzugrenzen von ‚unislamischen‘ Werten. Seit einigen Jahren dreht sich beispielsweise eine erhitzte gesellschaftliche Debatte um ein Gewaltschutzgesetz für Frauen, begleitet von einer medialen und religiösen Kampagne gegen Frauenschutzhäuser:
im Kern wird beiden vorgeworfen, antiislamisch zu sein. Frauenrechtsgruppen sehen sich gezwungen, juristisch und religiös zu begründen, dass das Gesetz keine Anteile aufweist, die dem Islam widersprechen.
Der hohe Rat der Ulema, 2002 von der Regierung eingesetzt und bezahlt, stellt die größte und einflussreichste religiöse Struktur in Afghanistan dar: er besteht aus 3000 Ulema und Mullas1 (davon ¾ Sunniten und ¼ Schiiten); viele sind gleichzeitig auch Richter, politische Berater, Lehrer oder Imame. Die meisten von ihnen gehören einer der Mudschahedin-Gruppierungen an. Auf nationaler Ebene berät der Rat die Regierung in religiösen Fragen, unterstützt zumeist ihre Entscheidungen und gewährt ihr so eine religiöse Legitimation; auf lokaler Ebene positionieren sich die Ulema und Mullas allerdings oft regierungskritisch und anti-westlich. In der gesellschaftlichen Debatte über Frauenrechte äußerten sie sich 2012 extrem konservativ, indem sie erklärten, Frauen seien weniger wert als Männer, sollten nicht ohne mahram (männlichen Verwandten) verreisen und bei Arbeit, Bildung und Freizeit den Kontakt zu Männern vermeiden. Ihre monatlichen Erklärungen auf nationaler Ebene sowie ihre Ansprachen in lokalen Moscheen haben großen Einfluss auf die gesellschaftliche Verhandlung von Normen. 2 Auch Saudi-Arabien versucht wachsenden Einfluss auf die religiöse Ausbildung in Afghanistan auszuüben, so z.B. durch den Bau und Betrieb eines religiösen Schulungszentrums in Kabul.3 Pakistanische religiöse Gelehrte sehen den Kampf der afghanischen Taliban gegen die westliche Intervention als berechtigt an, und erklären USA und NATO als allein verantwortlich für jegliche zivilen Opfer.
Under certain conditions, secondary organic aerosol (SOA) particles can exist in the atmosphere in an amorphous solid or semi-solid state. To determine their relevance to processes such as ice nucleation or chemistry occurring within particles requires knowledge of the temperature and relative humidity (RH) range for SOA to exist in these states. In the Cosmics Leaving Outdoor Droplets (CLOUD) experiment at The European Organisation for Nuclear Research (CERN), we deployed a new in situ optical method to detect the viscous state of α-pinene SOA particles and measured their transition from the amorphous highly viscous state to states of lower viscosity. The method is based on the depolarising properties of laboratory-produced non-spherical SOA particles and their transformation to non-depolarising spherical particles at relative humidities near the deliquescence point. We found that particles formed and grown in the chamber developed an asymmetric shape through coagulation. A transition to a spherical shape was observed as the RH was increased to between 35 % at −10 °C and 80 % at −38 °C, confirming previous calculations of the viscosity-transition conditions. Consequently, α-pinene SOA particles exist in a viscous state over a wide range of ambient conditions, including the cirrus region of the free troposphere. This has implications for the physical, chemical, and ice-nucleation properties of SOA and SOA-coated particles in the atmosphere.
There are strong indications that particles containing secondary organic aerosol (SOA) exhibit amorphous solid or semi-solid phase states in the atmosphere. This may facilitate deposition ice nucleation and thus influence cirrus cloud properties. However, experimental ice nucleation studies of biogenic SOA are scarce. Here, we investigated the ice nucleation ability of viscous SOA particles.
The SOA particles were produced from the ozone initiated oxidation of α-pinene in an aerosol chamber at temperatures in the range from −38 to −10 ◦C at 5–15 % relative humidity with respect to water to ensure their formation in a highly viscous phase state, i.e. semi-solid or glassy. The ice nucleation ability of SOA particles with different sizes was investigated with a new continuous flow diffusion chamber. For the first time, we observed heterogeneous ice nucleation of viscous α-pinene SOA in the deposition mode for ice saturation ratios between 1.3 and 1.4 significantly below the homogeneous freezing limit. The maximum frozen fractions found at temperatures between −36.5 and −38.3 °C ranged from 6 to 20 % and did not depend on the particle surface area. Global modelling of monoterpene SOA particles suggests that viscous biogenic SOA particles are indeed present in regions where cirrus cloud formation takes place. Hence, they could make up an important contribution to the global ice nuclei (IN) budget.
There are strong indications that particles containing secondary organic aerosol (SOA) exhibit amorphous solid or semi-solid phase states in the atmosphere. This may facilitate heterogeneous ice nucleation and thus influence cloud properties. However, experimental ice nucleation studies of biogenic SOA are scarce. Here, we investigated the ice nucleation ability of viscous SOA particles.
The SOA particles were produced from the ozone initiated oxidation of α-pinene in an aerosol chamber at temperatures in the range from −38 to −10 °C at 5–15 % relative humidity with respect to water to ensure their formation in a highly viscous phase state, i.e. semi-solid or glassy. The ice nucleation ability of SOA particles with different sizes was investigated with a new continuous flow diffusion chamber. For the first time, we observed heterogeneous ice nucleation of viscous α-pinene SOA for ice saturation ratios between 1.3 and 1.4 significantly below the homogeneous freezing limit. The maximum frozen fractions found at temperatures between −39.0 and −37.2 °C ranged from 6 to 20 % and did not depend on the particle surface area. Global modelling of monoterpene SOA particles suggests that viscous biogenic SOA particles are indeed present in regions where cirrus cloud formation takes place. Hence, they could make up an important contribution to the global ice nucleating particle budget.
Cloud microphysical processes involving the ice phase in tropospheric clouds are among the major uncertainties in cloud formation, weather and General Circulation Models (GCMs). The simultaneous detection of aerosol particles, liquid droplets, and ice crystals, especially in the small cloud-particle size range below 50 µm, remains challenging in mixed phase, often unstable ice-water phase environments. The Cloud Aerosol Spectrometer with Polarisation (CASPOL) is an airborne instrument that has the ability to detect such small cloud particles and measure their effects on the backscatter polarisation state. Here we operate the versatile Cosmics-Leaving- OUtdoor-Droplets (CLOUD) chamber facility at the European Organisation for Nuclear Research (CERN) to produce controlled mixed phase and other clouds by adiabatic expansions in an ultraclean environment, and use the CASPOL to discriminate between different aerosols, water and ice particles. In this paper, optical property measurements of mixed phase clouds and viscous Secondary Organic Aerosol (SOA) are presented. We report observations of significant liquid – viscous SOA particle polarisation transitions under dry conditions using CASPOL. Cluster analysis techniques were subsequently used to classify different types of particles according to their polarisation ratios during phase transition. A classification map is presented for water droplets, organic aerosol (e.g., SOA and oxalic acid), crystalline substances such as ammonium sulphate, and volcanic ash. Finally, we discuss the benefits and limitations of this classi- fication approach for atmospherically relevant concentration and mixtures with respect to the CLOUD 8–9 campaigns and its potential contribution to Tropical Troposphere Layer (TTL) analysis.
Cloud microphysical processes involving the ice phase in tropospheric clouds are among the major uncertainties in cloud formation, weather, and general circulation models. The detection of aerosol particles, liquid droplets, and ice crystals, especially in the small cloud particle-size range below 50 μm, remains challenging in mixed phase, often unstable environments. The Cloud Aerosol Spectrometer with Polarization (CASPOL) is an airborne instrument that has the ability to detect such small cloud particles and measure the variability in polarization state of their backscattered light. Here we operate the versatile Cosmics Leaving OUtdoor Droplets (CLOUD) chamber facility at the European Organization for Nuclear Research (CERN) to produce controlled mixed phase and other clouds by adiabatic expansions in an ultraclean environment, and use the CASPOL to discriminate between different aerosols, water, and ice particles. In this paper, optical property measurements of mixed-phase clouds and viscous secondary organic aerosol (SOA) are presented. We report observations of significant liquid–viscous SOA particle polarization transitions under dry conditions using CASPOL. Cluster analysis techniques were subsequently used to classify different types of particles according to their polarization ratios during phase transition. A classification map is presented for water droplets, organic aerosol (e.g., SOA and oxalic acid), crystalline substances such as ammonium sulfate, and volcanic ash. Finally, we discuss the benefits and limitations of this classification approach for atmospherically relevant concentrations and mixtures with respect to the CLOUD 8–9 campaigns and its potential contribution to tropical troposphere layer analysis.
The CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) passenger aircraft observatory performed in situ measurements at 10–12 km altitude in the South Asian summer monsoon anticyclone between June and September 2008. These measurements enable us to investigate this atmospheric region (which so far has mostly been observed from satellites) using the broad suite of trace gases and aerosol particles measured by CARIBIC. Elevated levels of a variety of atmospheric pollutants (e.g. carbon monoxide, total reactive nitrogen oxides, aerosol particles, and several volatile organic compounds) were recorded. The measurements provide detailed information about the chemical composition of air in different parts of the monsoon anticyclone, particularly of ozone precursors. While covering a range of 3500 km inside the monsoon anticyclone, CARIBIC observations show remarkable consistency, i.e. with distinct latitudinal patterns of trace gases during the entire monsoon period.
Using the CARIBIC trace gas and aerosol particle measurements in combination with the Lagrangian particle dispersion model FLEXPART, we investigated the characteristics of monsoon outflow and the chemical evolution of air masses during transport. The trajectory calculations indicate that these air masses originated mainly from South Asia and mainland Southeast Asia. Estimated photochemical ages of the air were found to agree well with transport times from a source region east of 90–95° E. The photochemical ages of the air in the southern part of the monsoon anticyclone were systematically younger (less than 7 days) and the air masses were mostly in an ozone-forming chemical mode. In its northern part the air masses were older (up to 13 days) and had unclear ozone formation or destruction potential. Based on analysis of forward trajectories, several receptor regions were identified. In addition to predominantly westward transport, we found evidence for efficient transport (within 10 days) to the Pacific and North America, particularly during June and September, and also of cross-tropopause exchange, which was strongest during June and July. Westward transport to Africa and further to the Mediterranean was the main pathway during July.