The decay b -> s g at NLL in the Standard Model

I present the Standard Model calculation of the decay rate for b -> s g (g denotes a gluon) at next-to-leading logarithms (NLL). In order to get a meaningful physical result, the decay b -> s g g and certain contributions of b -> s \bar{f} f (where f are the light quark flavours u, d and s) have to be included as well. Numerically we get BR^(NLL) = (5.0 +/- 1.0) * 10^{-3} which is more than a factor 2 larger than the leading logarithmic result BR^(LL) = (2.2 +/- 0.8) * 10^{-3}. Further, I consider the impact of this contribution on the charmless hadronic branching ratio BRc, which could be used to extract the CKM-ratio |V_(ub)/V_(cb)| with more accuracy. Finally, I have a short look at BRc in scenarios where the Wilson coefficient C_8 is enhanced by new physics.Comment: 7 pages including 5 postscript figures; uses epsfi

Quantification of the impact in mid-latitudes of chemical ozone depletion in the 1999/2000 Arctic polar vortex prior to the vortex breakup

International audienceFor the winter 1999/2000 transport of air masses out of the vortex to mid-latitudes and ozone destruction inside and outside the northern polar vortex is studied to quantify the impact of earlier winter (before March) polar ozone destruction on mid-latitude ozone. Nearly 112 000 trajectories are started on 1 December 1999 on 6 different potential temperature levels between 500?600 K and for a subset of these trajectories photo-chemical box-model calculations are performed. We linked a decline of ?0.9% of mid-latitude ozone in this layer occurring in January and February 2000 to ozone destruction inside the vortex and successive transport of these air masses to mid-latitudes. Further, the impact of denitrification, PSC-occurrence and anthropogenic chlorine loading on future stratospheric ozone is determined by applying various scenarios. Lower stratospheric temperatures and denitrification were found to play the most important role in the future evolution of polar ozone depletion

Filling a blank on the map: 60 years of fisheries in Equatorial Guinea

Despite a scarcity of pertinent information, it has been possible to reconstruct time series of marine fisheries catches for Equatorial Guinea from 1950 to 2010 using per capita fish consumption and population numbers for small-scale fisheries, catch rates and number of vessels for industrial fisheries and discard rates to estimate the discarded bycatch. Small-scale fisheries, industrial large-scale fisheries, domestic and legal and illegal foreign fisheries and their discards are all included. Total catches were estimated at 2.7 million tonnes over the time period considered, of which 653 000 t were caught domestically compared to 187 000 t reported by FAO. This shows that fisheries have more importance for Equatorial Guinea's food security than the official data suggest. In contrast to what is suggested by official figures, fisheries were shown to be strongly impacted by civil and political unrest; notably, they declined overall because of civil and political conflicts, socio-demographic dynamics, and a growing role of the newly discovered oil resources, which directly and indirectly threaten the food security of the people of Equatorial Guinea

MontanAqua : Wasserbewirtschaftung in Zeiten von Knappheit und globalem Wandel. Wasserbewirtschaftungsoptionen für die Region Crans-Montana-Sierre im Wallis

Das nationale Forschungsprogramm NFP 61 «Nachhaltige Wassernutzung » des Schweizerischen Nationalfonds hat sich zum Ziel gesetzt, wissenschaftliche Grundlagen zur nachhaltigen Wasserbewirtschaftung in der Schweiz zu liefern. Als Teil dieses Forschungsvorhabens wurde im Rahmen des Projektes MontanAqua die Wasserbewirtschaftung der Region Crans-Montana-Sierre (Wallis) untersucht. Es ging dabei darum, in enger Zusammenarbeit mit den in der Region betroffenen Akteuren nachhaltige Wassernutzungsstrategien für die Zukunft zu entwickeln. MontanAqua hat sich vertieft mit den bestehenden Systemen der Wasserbewirtschaftung auf der regionalen Skala (11 Gemeinden) auseinandergesetzt. Dazu wurden die zukünftigen Auswirkungen der klimatischen und sozioökonomischen Veränderungen einbezogen. Das Forschungsteam analysierte die aktuelle Situation anhand von quantitativen, qualitativen sowie kartografischen Methoden und kombinierte diese mit Modellberechnungen. Für die Modellierung der Zukunft wurden regionale Klimaszenarien und vier mit lokalen Akteuren entwickelte sozioökonomische Szenarien verwendet. Dieser Überblick fasst die Resultate des Projektes MontanAqua zusammen. Fünf wesentliche Fragen werden beantwortet und fünf Kernbotschaften erläutert. Zudem sind Empfehlungen für die Verantwortlichen der regionalen und kantonalen Wasserbewirtschaftung formuliert

Comparison of long-term field-measured and RUSLE-based modelled soil loss in Switzerland

Long-term field measurements to asses model-based soil erosion predictions by water are rare. We have compared field measurements based on erosion assessment surveys from a 10-year monitoring process with spatial-explicit model predictions with the Revised Universal Soil Loss Equation (RUSLE). Robust input data were available for both the mapped and the modelled parameters for 203 arable fields covering an area of 258 ha in the Swiss Midlands. The 1639 mapped erosion forms were digitized and converted to raster format with a 2 m resolution. A digital terrain model using 2 m resolution and a multiple flow direction algorithm for the calculation of the topographic factors and the support practice factor was available for modelling with the RUSLE. The other input data for the RUSLE were determined for each field. The comparison of mapped and modelled soil loss values revealed a substantially higher estimation of soil loss values from modelling by a factor of 8, with a mean mapped soil loss of 0.77 t/ha/yr vs. modelled soil loss of 6.20 t/ha/yr. However, high mapped soil losses of >4 t/ha/yr were reproduced quite reliably by the model, while the model predicted drastically higher erosion values for mapped losses of <4 t/ha/yr. Our study shows the value of long-term field data based on erosion assessment surveys for model evaluation. RUSLE-type model results should be compared with erosion assessment surveys at the field to landscape scale in order to improve the calibration of the model. Further factors related to land management like headlands, traffic lanes and potato furrows need to be included before they may be used for policy advice

Shrinking water bodies as hotspots of sand and dust storms: The role of land degradation and sustainable soil and water management

Sand and Dust Storms (SDS) are a natural phenomenon with important impacts on ecosystems and human society. SDS hotspots are mostly located in drylands, however their impact goes beyond national and regional boundaries, making them a global issue. Factors affecting SDS occurrence include weather and climate, land cover and soil surface conditions, geomorphology and terrain types. "Playas", the exposed beds of shrinking water bodies, play a significant role in dust generation. Land degradation and desertification processes play an important role on dust emission from playa sources, which is frequently triggered or increased by human activities such as unsustainable land and water use upstream, reduced vegetation cover on and around playas, and mechanical disturbance of the playa surfaces.It has been estimated that anthropogenic playa sources contribute 85% of global anthropogenic dust emissions. Anthropogenic playa sources are frequently located near human settlements, so that even relatively small dust sources can have severe socio-economic and environmental impacts, including soil salinization and soil pollution when playa sediments are salt-rich or polluted. In these contexts, the implementation of sustainable land and water management (SLWM) measures and integrated watershed planning is particularly urgent to reduce dust emission and its impacts. The United Nations Conventions to Combat Desertification (UNCCD) identified the mitigation of anthropogenic SDS sources as a major pillar towards combating SDS.The number of scientific articles addressing this issue is rapidly increasing, but our understanding of SDS emitted from anthropogenic playa sources remains limited and fragmented. This article reviews the literature on playa sources that are recognized to be mainly anthropogenic in nature, with particular focus on the anthropogenic drivers, the SDS-related impacts, and the possible SLWM-based solutions to reduce SDS impact