Möglichkeiten verstärkter Nord-Süd-Technologiekooperation im Klimaregime: Studie auf Grundlage einer Analyse für das Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit im Rahmen des Projekts Wirtschaftliche Chancen der internationalen Klimapolitik

Dieses Papier gibt einen Überblick über die verschiedenen Formen der Technologiekooperation und prüft ihre Verwendbarkeit für die internationalen post-2012-Klimaverhandlungen. Es plädiert für einen umfassenden Ansatz unter Einbeziehung aller Elemente, also des gemeinsamen RD&D, der gemeinsamen Standardsetzung und der Finanzierung neuer Technologien. Die Vor- und Nachteile eines separaten Technologieprotokolls werden abgewogen - wobei die Nachteile überwiegen. Abschließend wird, unter Verweis auf die Verhandlungen in Bali, die Gründung einer Technologieallianz für Klimaschutz mit den Entwicklungs- und insbesondere den Schwellenländern empfohlen. Dies würde die post-2012-Verhandlungen entscheidend voranbringen, die diplomatische und technologische Zusammenarbeit mit den aufstrebenden Schwellenländern stärken und die Führungsrolle der Europäischen Union in der Klimapolitik - aber nicht nur dort - festigen. -- This paper provides an overview on the different forms of inter-governmental technology cooperation and examines their usefulness for the international climate negotiations post-2012. It advocates a comprehensive approach including all elements, i.e. common research and development, common setting of standards, technology transfer and financing of new technologies. The pros and cons of a separate technology protocol are evaluated: in the end, it is only a second-best option. Finally, taking the negotiations in Bali as a starting point, the paper envisions a technology alliance for climate protection with the developing countries - especially the emerging economies. This would significantly boost the post-2012 negotiations, strengthen diplomatic and technological cooperation and consolidate the European Union's leading role in climate politics - and other policy fields.

In situ measurements of tropical cloud properties in the West African Monsoon: upper tropospheric ice clouds, Mesoscale Convective System outflow, and subvisual cirrus

In situ measurements of ice crystal size distributions in tropical upper troposphere/lower stratosphere (UT/LS) clouds were performed during the SCOUT-AMMA campaign over West Africa in August 2006. The cloud properties were measured with a Forward Scattering Spectrometer Probe (FSSP-100) and a Cloud Imaging Probe (CIP) operated aboard the Russian high altitude research aircraft M-55 Geophysica with the mission base in Ouagadougou, Burkina Faso. A total of 117 ice particle size distributions were obtained from the measurements in the vicinity of Mesoscale Convective Systems (MCS). Two to four modal lognormal size distributions were fitted to the average size distributions for different potential temperature bins. The measurements showed proportionately more large ice particles compared to former measurements above maritime regions. With the help of trace gas measurements of NO, NOy, CO2, CO, and O3 and satellite images, clouds in young and aged MCS outflow were identified. These events were observed at altitudes of 11.0 km to 14.2 km corresponding to potential temperature levels of 346 K to 356 K. In a young outflow from a developing MCS ice crystal number concentrations of up to (8.3 ± 1.6) cm−3 and rimed ice particles with maximum dimensions exceeding 1.5 mm were found. A maximum ice water content of 0.05 g m−3 was observed and an effective radius of about 90 μm. In contrast the aged outflow events were more diluted and showed a maximum number concentration of 0.03 cm−3, an ice water content of 2.3 × 10−4 g m−3, an effective radius of about 18 μm, while the largest particles had a maximum dimension of 61 μm. Close to the tropopause subvisual cirrus were encountered four times at altitudes of 15 km to 16.4 km. The mean ice particle number concentration of these encounters was 0.01 cm−3 with maximum particle sizes of 130 μm, and the mean ice water content was about 1.4 × 10−4 g m−3. All known in situ measurements of subvisual tropopause cirrus are compared and an exponential fit on the size distributions is established for modelling purposes. A comparison of aerosol to ice crystal number concentrations, in order to obtain an estimate on how many ice particles may result from activation of the present aerosol, yielded low ratios for the subvisual cirrus cases of roughly one cloud particle per 30 000 aerosol particles, while for the MCS outflow cases this resulted in a high ratio of one cloud particle per 300 aerosol particles

Numerical simulation of the impact of COVID-19 lockdown on tropospheric composition and aerosol radiative forcing in Europe

Aerosols influence the Earth\u27s energy balance directly by modifying the radiation transfer and indirectly by altering the cloud microphysics. Anthropogenic aerosol emissions dropped considerably when the global COVID-19 pandemic resulted in severe restraints on mobility, production, and public life in spring 2020. We assess the effects of these reduced emissions on direct and indirect aerosol radiative forcing over Europe, excluding contributions from contrails. We simulate the atmospheric composition with the ECHAM5/MESSy Atmospheric Chemistry (EMAC) model in a baseline (business-as-usual) and a reduced emission scenario. The model results are compared to aircraft observations from the BLUESKY aircraft campaign performed in May–June 2020 over Europe. The model agrees well with most of the observations, except for sulfur dioxide, particulate sulfate, and nitrate in the upper troposphere, likely due to a biased representation of stratospheric aerosol chemistry and missing information about volcanic eruptions. The comparison with a baseline scenario shows that the largest relative differences for tracers and aerosols are found in the upper troposphere, around the aircraft cruise altitude, due to the reduced aircraft emissions, while the largest absolute changes are present at the surface. We also find an increase in all-sky shortwave radiation of 0.21 ± 0.05 W m⁻² at the surface in Europe for May 2020, solely attributable to the direct aerosol effect, which is dominated by decreased aerosol scattering of sunlight, followed by reduced aerosol absorption caused by lower concentrations of inorganic and black carbon aerosols in the troposphere. A further increase in shortwave radiation from aerosol indirect effects was found to be much smaller than its variability. Impacts on ice crystal concentrations, cloud droplet number concentrations, and effective crystal radii are found to be negligible

Impact of reduced emissions on direct and indirect aerosol radiative forcing during COVID-19 lockdown in Europe

Aerosols influence the Earth’s energy balance through direct radiative effects and indirectly by altering the cloud microphysics. Anthropogenic aerosol emissions dropped considerably when the global COVID–19 pandemic resulted in severe restraints on mobility, production, and public life in spring 2020. Here we assess the effects of these reduced emissions on direct and indirect aerosol radiative forcing over Europe, excluding contributions from contrails. We simulate the atmospheric composition with the ECHAM5/MESSy Atmospheric Chemistry (EMAC) model in a baseline (business as usual) and a reduced emission scenario. The model results are compared to aircraft observations from the BLUESKY aircraft campaign performed in May June 2020 over Europe

Stratospheric aerosol - Observations, processes, and impact on climate

Interest in stratospheric aerosol and its role in climate have increased over the last decade due to the observed increase in stratospheric aerosol since 2000 and the potential for changes in the sulfur cycle induced by climate change. This review provides an overview about the advances in stratospheric aerosol research since the last comprehensive assessment of stratospheric aerosol was published in 2006. A crucial development since 2006 is the substantial improvement in the agreement between in situ and space-based inferences of stratospheric aerosol properties during volcanically quiescent periods. Furthermore, new measurement systems and techniques, both in situ and space based, have been developed for measuring physical aerosol properties with greater accuracy and for characterizing aerosol composition. However, these changes induce challenges to constructing a long-term stratospheric aerosol climatology. Currently, changes in stratospheric aerosol levels less than 20% cannot be confidently quantified. The volcanic signals tend to mask any nonvolcanically driven change, making them difficult to understand. While the role of carbonyl sulfide as a substantial and relatively constant source of stratospheric sulfur has been confirmed by new observations and model simulations, large uncertainties remain with respect to the contribution from anthropogenic sulfur dioxide emissions. New evidence has been provided that stratospheric aerosol can also contain small amounts of nonsulfate matter such as black carbon and organics. Chemistry-climate models have substantially increased in quantity and sophistication. In many models the implementation of stratospheric aerosol processes is coupled to radiation and/or stratospheric chemistry modules to account for relevant feedback processes

Möglichkeiten verstärkter Nord-Süd-Technologiekooperation im Klimaregime : Studie auf Grundlage einer Analyse für das Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit im Rahmen des Projekts "Wirtschaftliche Chancen der internationalen Klimapolitik" (FKZ 90511504)

Dieses Papier gibt einen Überblick über die verschiedenen Formen der Technologiekooperation und prüft ihre Verwendbarkeit für die internationalen post-2012-Klimaverhandlungen. Es plädiert für einen umfassenden Ansatz unter Einbeziehung aller Elemente, also des gemeinsamen RD&D, der gemeinsamen Standardsetzung und der Finanzierung neuer Technologien. Die Vor- und Nachteile eines separaten Technologieprotokolls werden abgewogen - wobei die Nachteile überwiegen. Abschließend wird, unter Verweis auf die Verhandlungen in Bali, die Gründung einer Technologieallianz für Klimaschutz mit den Entwicklungs- und insbesondere den Schwellenländern empfohlen. Dies würde die post-2012-Verhandlungen entscheidend voranbringen, die diplomatische und technologische Zusammenarbeit mit den aufstrebenden Schwellenländern stärken und die Führungsrolle der Europäischen Union in der Klimapolitik - aber nicht nur dort - festigen

Internationale Finanzmittel für den Klimaschutz : bestehende und zukünftige Finanzmechanismen im internationalen Klimaregime zur Minderung von Treibhausgasen und zur Anpassung an den Klimawandel

Aufgrund der asymmetrischen Struktur von Ursache und Wirkung (historische Hauptverursacher im Norden, besondere Verwundbarkeit des Südens) und aufgrund der schnell aufholenden Entwicklung der Schwellenländer sind vor allem die Nord-Süd-Beziehungen ein entscheidender Faktor bei der Bewältigung des Klimaproblems. Die "alten", traditionellen Industriestaaten werden die sich industrialisierenden Staaten des Südens nur dann zu eigenen Minderungsleistungen bewegen können, wenn sie - neben eigenen ambitionierten Reduktionen - auch in hohem Maße die Minderungsmaßnahmen im Süden finanzieren und die ärmeren Staaten bei der Anpassung unterstützen. Technologische Unterstützung und Finanzierung sind deshalb bei der internationalen Klimakonferenz (COP13) in Bali im Jahr 2007 zu einem Kernprojekt für die post-2012-Verhandlungen geworden. Selbst konservative Schätzungen rechnen mit mehreren Dutzend Milliarden US-Dollar für die Minderung des Treibhausgasausstoßes und für Anpassungsmaßnahmen pro Jahr. Es ist daher nötig, bei der Finanzierung der Bekämpfung des Klimawandels nicht allein auf staatliche Mittel zu setzen, sondern auch private Mittel verstärkt mit einzubeziehen. Diese Kurzstudie, die für das Bundesministerium für wirtschaftliche Zusammenarbeit und Entwicklung (BMZ) Anfang 2008 erstellt wurde, bietet eine Aufstellung und Bewertung der bestehenden Finanzierungsoptionen auf multilateraler (und zum Teil bilateraler) Ebene, sowie eine Darstellung von in der Planung befindlichen Instrumenten und innovativer Vorschläge für neue Formen der Zusammenarbeit von staatlichen und privaten Akteuren