Recovery and protection of coastal ecosystems after tsunami event and potential for participatory forestry CDM – Examples from Sri Lanka

By using an integrated approach, tsunami affected land, vegetation and inhabitants were assessed to evaluate the potential to restore and protect coastal land in the context of Kyoto Protocol's Clean Development Mechanism in Hambantota district in the south-eastern part of Sri Lanka. Firstly, assessments of the status of the tsunami affected area were carried out by collecting soil and well water samplings for carbon and salinity analysis. Secondly, identification of potential tree species for carbon sequestration and sustainable development was conducted to determine carbon stock and suitability to grow under the prevailing conditions. In addition, interviews to understand the local people's perception of forest plantations and land use were conducted. The results showed that the resilience process of salt intruded lands from the 2004 Asian tsunami has progressed rapidly with low salinity level in the soils 14 months after the event, while the well water showed evidence of salinity contamination. The carbon stock was highest in natural forests followed by coconut plantations. Land users could envision expanding their present plantations or establish new ones. The barriers were defined as lack of financial investment capital and limited land for extended plantations. If a Clean Development Mechanism project is to be established, the coconut tree was found to be the most appropriate tree species since it has high carbon content, had co-benefits and possesses a salt-tolerant characteristic. Finally, the tsunami event has triggered land users to perceive environmental benefits of protection from mangrove or other adequate vegetation such as coconut plantations as welcome and desired to decrease their vulnerability. The assessment of multi-functionality of forest plantations, such as small-scale community based Clean Development Mechanism, its generated income from carbon credits as well as the wish for environmental protection should be considered to increase the attractiveness of plantation projects in the coastal areas.     

Analysis of uncertainties in the hydrological response of a model‐based climate change impact assessment in a subcatchment of the Spree River,Germany

Climate change impact assessments form the basis for the development of suitable climate change adaptation strategies. For this purpose, ensembles consisting of stepwise coupled models are generally used [emission scenario → global circulation model → downscaling approach (DA) → bias correction → impact model (hydrological model)], in which every item is affected by considerable uncertainty. The aim of the current study is (1) to analyse the uncertainty related to the choice of the DA as well as the hydrological model and its parameterization and (2) to evaluate the vulnerability of the studied catchment, a subcatchment of the highly anthropogenically impacted Spree River catchment, to hydrological change. Four different DAs are used to drive four different model configurations of two conceptually different hydrological models (Water Balance Simulation Model developed at ETH Zürich and HBV‐light). In total, 452 simulations are carried out. The results show that all simulations compute an increase in air temperature and potential evapotranspiration. For precipitation, runoff and actual evapotranspiration, opposing trends are computed depending on the DA used to drive the hydrological models. Overall, the largest source of uncertainty can be attributed to the choice of the DA, especially regarding whether it is statistical or dynamical. The choice of the hydrological model and its parameterization is of less importance when long‐term mean annual changes are compared. The large bandwidth at the end of the modelling chain may exacerbate the formulation of suitable climate change adaption strategies on the regional scale. Copyright © 2013 John Wiley & Sons, Ltd.     

Accretion and exhumation at a Variscan active margin, recorded in the Saxothuringian flysch

The Saxothuringian flysch basin, on the north flank of the Central European Variscides, was fed and eventually overthrust by the northwestern, active margin of the Tepla-Barrandian terrane. Clast spectra, mineral composition and isotopic ages of detrital mica and zircon have been analyzed in order to constrain accretion and exhumation of rocks in the orogenic wedge. The earliest clastic sediments preserved are of early Famennian age (ca. 370?Ma). They are exposed immediately to the NW of the suture, and belong to the par-autochthon of the foreland. Besides ultramafic (?ophiolite) material, these rocks contain clasts derived from Early Paleozoic continental slope sediments, originally deposited at the NW margin of the Saxothuringian basin. These findings, together with the paleogeographic position of the Famennian clastics debris on the northwestern passive margin, indicate that the Saxothuringian narrow ocean had been closed by that time. Microprobe analyses of detrital hornblendes suggest derivation from the “Randamphibolit” unit, now present in the middle part of the Saxothuringian allochthon (Münchberg nappes). Detrital zircons of metamorphic rocks formed a little earlier (ca. 380?Ma) indicate rapid recycling at the tectonic front. The middle part of the flysch sequence (ca. early to middle Viséan), both in the par-autochthon and in the allochthon, contains abundant clasts of Paleozoic rocks derived from the northwestern slope and rise, together with debris of Cadomian basement, 500-Ma granitoids and 380?Ma (early Variscan) crystalline rocks. All of these source rocks were still available in the youngest part of the flysch (c. middle to late Viséan), but some clasts record, in addition, accretion of the northwestern shelf. Our findings permit deduction of minimum rates of tectonic shortening well in excess of 10–30?mm per year, and rates of exhumation of ca. 3?mm/a, and possibly more.     

Hydrological system analysis and modelling of the Kara River basin (West Africa) using a lumped metric conceptual model

This paper discusses the analysis and modelling of the hydrological system of the basin of the Kara River, a transboundary river in Togo and Benin, as a necessary step towards sustainable water resources management. The methodological approach integrates the use of discharge parameters, flow duration curves and the lumped conceptual model IHACRES. A Sobol sensitivity analysis is performed and the model is calibrated by applying the shuffled complex evolution algorithm. Results show that discharge generation in three nested catchments of the basin is affected by landscape physical characteristics. The IHACRES model adequately simulates the rainfall–runoff dynamics in the basin with a mean modified Nash-Sutcliffe efficiency measure of 0.6. Modelling results indicate that parameters controlling rainfall transformation to effective rainfall are more sensitive than those routing the streamflow. This study provides insights into understanding the catchment’s hydrological system. Nevertheless, further investigations are required to better understand detailed runoff generation processes.

EDITOR M.C. Acreman; ASSOCIATE EDITOR N Verhoest     

Brest sea level record: a time series construction back to the early eighteenth century

The completeness and the accuracy of the Brest sea level time series dating from 1807 make it suitable for long-term sea level trend studies. New data sets were recently discovered in the form of handwritten tabulations, including several decades of the eighteenth century. Sea level observations have been made in Brest since 1679. This paper presents the historical data sets which have been assembled so far. These data sets span approximately 300 years and together constitute the longest, near-continuous set of sea level information in France. However, an important question arises: Can we relate the past and the present-day records? We partially provide an answer to this question by analysing the documents of several historical libraries with the tidal data using a ‘data archaeology’ approach advocated by Woodworth (Geophys Res Lett 26:1589–1592, 1999b). A second question arises concerning the accuracy of such records. Careful editing was undertaken by examining the residuals between tidal predictions and observations. It proved useful to remove the worst effects of timing errors, in particular the sundial correction to be applied prior to August 1, 1714. A refined correction based on sundial literature [Savoie, La gnomique, Editions Les Belles Lettres, Paris, 2001] is proposed, which eliminates the systematic offsets seen in the discrepancies in timing of the sea level measurements. The tidal analysis has also shown that shallow-water tidal harmonics at Brest causes a systematic difference of 0.023 m between mean sea level (MSL) and mean tide level (MTL). Thus, MTL should not be mixed with the time series of MSL because of this systematic offset. The study of the trends in MTL and MSL however indicates that MTL can be used as a proxy for MSL. Three linear trend periods are distinguished in the Brest MTL time series over the period 1807–2004. Our results support the recent findings of Holgate and Woodworth (Geophys Res Lett) of an enhanced coastal sea level rise during the last decade compared to the global estimations of about 1.8 mm/year over longer periods (Douglas, J Geophys Res 96:6981–6992, 1991). The onset of the relatively large global sea level trends observed in the twentieth century is an important question in the science of climate change. Our findings point out to an ‘inflexion point’ at around 1890, which is remarkably close to that in 1880 found in the Liverpool record by Woodworth (Geophys Res Lett 26:1589–1592, 1999b).     

Bias of ostracod stable isotope data caused by drying of sieve residues from water

Stable isotope analysis of ostracod shells is used routinely for palaeoenvironmental studies of ostracod-bearing records. Sample treatment usually involves the disaggregation of sediments and sieving; before the sieving residues were washed with water onto petri dishes and oven-dried. In our study, we compared δ¹⁸O and δ¹³C values of shells that were oven-dried from water and from ethanol alternatively. Large isotopic differences of up to 3‰ were determined for δ¹⁸O values, whereas differences in δ¹³C values were less pronounced with differences of up to 1.6‰. Stable isotope values of shells dried from water were lower for both oxygen and carbon as a result of calcite crystals precipitated on the shell surfaces during the drying process. Therefore, ostracod shells for stable isotope analysis should not be prepared by drying from water. Instead, shells should be dried from ethanol to obtain reliable stable isotope data; likewise freeze-drying is expected to provide trustworthy results.     

Regional GHG reduction targets based on effort sharing: a comparison of studies

Over 40 studies that analyse future GHG emissions allowances or reduction targets for different regions based on a wide range of effort-sharing approaches and long-term concentration stabilization levels are compared. This updates previous work undertaken for the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Regional reduction targets differ significantly for each effort-sharing approach. For example, in the Organisation for Economic Co-operation and Development (OECD) 1990 region, new proposals that emphasize the equity principles of responsibility, capability, and need, and those based on equal cumulative per capita emissions (carbon budgets), lead to relatively stringent emissions reduction targets. In order to reach a low concentration stabilization level of 450?ppm CO₂e, the allowances under all effort sharing approaches in OECD1990 for 2030 would be approximately half of the emissions of 2010 with a large range, roughly two-thirds in the Economies in Transition (EIT), roughly at the 2010 emissions level or slightly below in Asia, slightly above the 2010 level in the Middle East and Africa and well below the 2010 level in Latin America. For 2050, allowances in OECD1990 and EIT would be a fraction of today's emissions, approximately half of 2010 emission levels in Asia, and possibly less than half of the 2010 level in Latin America.

Policy relevance

The concept of equity and the stringency of future national GHG reduction targets are at the heart of the current debate on the new international climate change agreement to be adopted in 2015. Policy insights gained from an analysis of over 40 studies, which have quantitatively analysed the proposed GHG reduction targets, are presented. It is found that the outcome of effort-sharing approaches is often largely determined by the way the equity principle is implemented and that the distributional impacts of such approaches can be significantly different depending on the criteria used, the stabilization level and shape of the global emissions pathway. However, the current literature only covers a small proportion of the possible allocation approaches. There should thus be an in-depth modelling comparison to ensure consistency and comparability of results and inform decision making regarding the reduction of GHG emissions.     

Outer convection zones and internal temperatures of cool white dwarfs

The outer convection zone of the low-temperature white dwarf Van Maanen 2 has been studied for two different atmospheric models given byWeidemann (1960). A slight modification of the standard mixing length theory and the abundances derived by Weidemann have been used.The thickness of the convection zone is about 8 km for the atmospheric model withT _eff=5780 K,g=10⁸ cm sec^–2 and about 23 km forT _eff=5040,g=3.16×10⁷K. In both cases the temperature at the lower boundary of the convection zone is about 9.8×10⁵K. It is shown that this temperature corresponds approximately to the transition temperatureT _tr to the (almost) isothermal core of the white dwarf. This value is considerably lower than the values ofT _tr discussed in the literature until now.The outer convection zone consists of an upper completely non-degenerate part and a lower part with moderate degeneracy. In this lower part the degree of degeneracy is practically independent of depth.