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We present a new set of global and local sea-level projections at example tide gauge locations under the RCP2.6, RCP4.5 and RCP8.5 emissions scenarios. Compared to the CMIP5-based sealevel projections presented in IPCC AR5, we introduce a number of methodological innovations, including: (i) more comprehensive treatment of uncertainties; (ii) direct traceability between global and local projections; (iii) exploratory extended projections to 2300 based on emulation of individual CMIP5 models. Combining the projections with observed tide gauge records, we explore the contribution to total variance that arises from sea-level variability, different emissions scenarios and model uncertainty. For the period out to 2300 we further breakdown the model uncertainty by sea-level component and consider the dependence on geographic location, time horizon and emissions scenario. Our analysis highlights the importance of variability for sea-level change in the coming decades and the potential value of annual-to-decadal predictions of local sea-level change. Projections to 2300 show a substantial degree of committed sea-level rise under all emissions scenarios considered and highlights the reduced future risk associated with RCP2.6 and RCP4.5 compared to RCP8.5. Tide gauge locations can show large (> 50%) departures from the global average, in some cases even reversing the sign of the change. While uncertainty in projections of the future Antarctic ice dynamic response tends to dominate post2100, we see a substantial differences in the breakdown of model variance as a function of location, timescale and emissions scenario.

This chapter studies the role played by small entrepreneurial firms and large companies in the international biotechnology industry. The biotechnology industry is one of the main examples of current industries that are characterized by “hypercompetition”, with a high degree of uncertainty about the combined effects of both new technologies and new market structures. It is an example of an industry with Schumpeterian competition where revolutionary changes in technology and innovative new products and processes have the potential to threaten the position of existing market leaders and their product-market positions. It is also a sector where we find a large number of R&D alliances, in particular between large and small companies.

One task of the German National Climate Modeling Initiative PalMod will be to couple earth system models representing the atmospere, ocean and ice dynamics during the last glacial cycle with the dynamic loading response of a viscoelastic earth model. In preparation, we discuss in this study the influence of viscosity stratification and of lateral heterogeneities in the Earth structure on the solid-earth response to glacial loading. As discussed in literature, there is a controversy about the impact of lateral heterogeneity on the prediction of present and past GIA signals. The influence of the Earth structure on the far-field response is governed by the flexural behaviour of the regional lithosphere and upper-mantle structure in response to the varying ocean load. The influence at and around the glacial ice sheets is substantial with respect to the amplitudes and also with respect to the temporal evolution of the earth’s response. Depending on the region of interest, lithospheric variations are present over the extent of the glacial ice sheets varying between 40 and 200 km, and lateral variations in viscosity can vary by one or two orders of magnitude. The focus will be to what extent the behaviour of a laterally heterogeneous viscosity structure can be parameterised by an adjusted spherical earth model representation. Accordingly, we apply predefined ice-sheet histories (like ICE5G and ICE6G) and analyse ensemble runs representing the variability of relative sea-level and palaeotopography predictions. Spatial pattern of deformation fields will be discussed as the behaviour at specific sea-level curves. Furthermore, we compare the sensitivity on earth structure during the evolution of sea level and palaeo topography during the termination phase of the last glaciation to present-day rates of relative sea-level height and radial displacement.

The recent advent of new high-resolution datasets of electromagnetic induction allows novel combinations of observations and models. The ocean induced magnetic field provides the potential to indirectly observe the ocean general circulation and may be utilized by data assimilation techniques. The modelling of the ocean induced magnetic field is affected by various uncertainties that originate from errors in the input data and from the applied model itself. The amount of aggregated uncertainties and their effect on the modelling of electromagnetic induction in the ocean is unknown. However, the knowledge of model uncertainties is essential for many research questions. To investigate the uncertainty in the modelling of motional induction, ensemble simulations with an ocean general circulation model and an electromagnetic induction model are performed on the basis of different error scenarios. This approach allows to estimate both the spatial distribution and temporal variation of the uncertainty. The largest uncertainty in the motionally induced magnetic field occurs in the area of the Antarctic Circumpolar Current. Local maxima reach values of up to 0.7 nano Tesla (nT). The estimated global annual mean uncertainty in the motionally induced magnetic field ranges from 0.1 to 0.4 nT. The relative amount of uncertainty reaches up to 30 % of the induced magnetic signal strength with largest values in regions in the northern hemisphere. The major source of uncertainty is found to be introduced by the wind stress from the atmospheric forcing of the ocean model. In addition, the temporal evolution of the uncertainty in the motionally induced magnetic field shows distinct seasonal variations. Specific regions are identified which are robust with respect to the introduced uncertainties.

Contains fulltext : 68663.pdf (Publisher’s version ) (Closed access) 12 p.

Within the project SPOT (Short Period Ocean Tidal variations in Earth rotation), we develop an improved model of short period ocean tidal effects in polar motion and length-of-day. Thereby, we need to determine the contributions of individual tidal constituents to the variation in polar motion and length-of-day in terms of oceanic tidal angular momentum (OTAM). Recent studies show that minor tides from admittance theory, hydrodynamic modelling and estimated from satellite altimetry differ significantly. Here minor tides describe all tidal constituents which are not in the group of {K1,O1,P1,Q1, M2,S2,N2,K2} in the diurnal and semidiurnal band. Therefor, we investigate systematically the influence of different implementations of admittance theory for minor tides on OTAM. In addition, we study the influence of different tidal heights models, like EOT11a, HAMTIDE and FES2012, as well as linear and quadratic admittance for semidiurnal tides.

Contains fulltext : 134100.pdf (Publisher’s version ) (Closed access) This research studies the effect of specific institutional and distance cost issues, in particular the protection of intellectual property rights and geographic distance, on the preference of companies for different governance modalities in terms of the degree of their involvement in international relational-based technology alliances. In the sample, all technology alliances contain exclusive technology agreements. We find that international differences in intellectual property rights protection regimes between the home countries of partnering companies are a significant factor: the larger the difference, the more likely that partnering companies prefer to form an equity relational-based technology alliance with substantial inter-partner involvement. The degree of geographic distance between partners also affects the preference of companies for a particular form of relational-based agreement. Companies prefer to engage in deeper inter-partner involvement, albeit of a non-equity nature, in case of large geographic distance between the home countries of the partnering companies. 12 p.

This note examines isomorphism and diversity in a global industry. We study how the ongoing internationalisation process has affected companies from various regions of the world. Empirical research is focussed on the international computer industry. We find that companies in this sector have become more divergent and that there is little evidence of a process of isomorphism.© 2001 JIBS. Journal of International Business Studies (2001) 32, 347–356

In recent years, a number of studies have addressed the problem of constraining subglacial geothermal heat flow (SGHF) patterns within the context of thermodynamic ice-sheet modeling. This study reports on the potential of today’s ice-sheet modeling methods and, more importantly, their limitations, with respect to reproducing the thermal states of the present-day large-scale ice sheets. So far, SGHF-related ice-sheet studies have suggested two alternative approaches for obtaining the present-day ice-sheet temperature distribution: (i) paleoclimatic simulations driven by the past surface temperature reconstructions, and (ii) fixed-topography steady-state simulations driven by the present-day climate conditions. Both approaches suffer from a number of shortcomings that are not easily amended. Paleoclimatic simulations account for past climate variations and produce more realistic present-day ice temperature distribution. However, in some areas, our knowledge of past climate forcing is subject to larger uncertainties that exert a significant influence on both the modeled basal temperatures and ice thicknesses, as demonstrated by our sensitivity case study applied to the Greenland Ice Sheet (GIS). In some regions of the GIS, for example southern Greenland, the poorly known climate forcing causes a significant deviation of the modeled ice thickness from the measured values (up to 200 meters) and makes it impossible to fit the measured basal temperature and gradient unless the climate history forcing is improved. Since present-day ice thickness is a product of both climate history and SGHF forcing, uncertainties in either boundary condition integrated over the simulation time will lead to a misfit between the modeled and observed ice sheets. By contrast, the fixed-topography steadystate approach allows one to avoid the above-mentioned transient effects and fit perfectly the observed present-day ice surface topography. However, the temperature distribution resulting from steady-state simulations strongly depends on the choice of the present-day climate forcing. Thus, employing average temperature/precipitation forcings from either the end of the 20th century or the beginning of the 21st century leads to differences of 5-10 mW/m2 in the predicted SGHF values. Regardless of the climate forcing employed, a close match between the measured and modeled basal temperatures can be easily achieved by varying the SGHF forcing. Yet this approach fails to reproduce the shape of measured temperature profiles, nor the measured basal temperature gradients. We conclude that a use of steady-state simulations is unlikely to lead to correct estimations for SGHF values, whereas paleoclimatic simulations are potentially capable of producing quantitative estimations of the SGHF distribution, depending on the quality of the climate forcing.

This report continues a series of Scientific Technical Reports, in which the theoretical description of the electromagnetic (EM, see Hagedoorn & Greiner-Mai, 2008), topographic (TOP, see Greiner-Mai & Hagedoorn, 2008) and gravitational (GRAV, see Hagedoorn et al., 2012) core-mantle coupling torques are presented in detail. Based on these theoretical descriptions numerical codes were developed to compute individual coupling torques.

When modelling the glacial-isotatic adjustment (GIA) by an initial value approach, the earth is assumed to be hydrostatically prestressed in an initial state. Including the sea-level equation in a solution requires, in addition, to define an initial topography, for which the present-day topography is mostly chosen. At the first view, this choice is reasonable: Topographical variability is by a few orders of magnitude larger than the residual surface deformation at present time due to GIA, which is at most of the order of 100 m in northern Canada and some parts of Antarctica. But, when considering the effect of the time-varying ocean load, the influence of palaeotopography may become important. Assuming that coast lines follow the sea level, we determine the initial topography in such a way that the predicted present-day topography after one glacial cycle coincides with the actual topography. We discuss consequences for the prediction of geodetic and geological observables as for the reconstruction of palaeo-sea level.

Different processes influence the variation of the Earth’s rotation on decadal time scale. The consideration of surface processes, like the exchange of angular momentum of the fluid sub-systems of atmosphere and ocean, and coupling processes at the core-mantle boundary like electromagnetic and topographic coupling torques, lead still to significant differences between observed and modelled Earth rotation parameters (ERP). For the modelled ERP, we consider the electromagnetic (EM) and topographic (TOP) core-mantle coupling torques and compute equivalent excitation functions, which are combined with atmospheric (AAM) and oceanic (OAM) angular momentum functions. Our investigation is focused on an additional core-mantle coupling process, the gravitational coupling, which should partly explain the remaining differences between modelled and observed ERP. The influence of assumed geometrical settings, like flattening and topography of the core-mantle (CMB) and inner-core (ICB) boundary on the gravitational coupling torque are studied systematically. First, simplified geometrical settings are applied, where the CMB and ICB are represented by two-axial ellipsoids. In a second step, published CMB topographies based on seismic tomography are considered and the resulting torques are compared with the simplified case. Results from this study will be used for the further extension of our core-mantle coupling model by the gravitational core-mantle coupling.