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Changes to mean sea level and/or sea level extremes (e.g., storm surges) will lead to changes in coastal impacts. These changes represent a changing exposure or risk to our society. Here, we present 21st century sea-level projections for Norway largely based on the Fifth Assessment Report from the Intergovernmental Panel for Climate Change (IPCC AR5). An important component of past and present sea-level change in Norway is glacial isostatic adjustment. We therefore pay special attention to vertical land motion, which is constrained using new geodetic observations with improved spatial coverage and accuracies, and modelling work. Projected ensemble mean 21st century relative sea-level changes for Norway are, depending on location, from −0.10 to 0.30 m for emission scenario RCP2.6; 0.00 to 0.35 m for RCP 4.5; and 0.15 to 0.55 m for RCP8.5. For all RCPs, the projected ensemble mean indicates that the vast majority of the Norwegian coast will experience a rise in sea level. Norway’s official return heights for extreme sea levels are estimated using the average conditional exceedance rate (ACER) method. We adapt an approach for calculating sea level allowances for use with the ACER method. All the allowances calculated give values above the projected ensemble mean Relative Sea Level (RSL) rise, i.e., to preserve the likelihood of flooding from extreme sea levels, a height increase above the most likely RSL rise should be used in planning. We also show that the likelihood of exceeding present-day return heights will dramatically increase with sea-level rise.

Cationic gemini surfactants with chiral counterions such as L-tartrate form gels by developing extended networks of multilamellar twisted ribbons. The chirality comes from the counterion, rather than from the amphiphile. Similar structures are found for diacetylenic lipids, glutamates and bile. The helical ribbons are unstable, evolving into tubules. Twisted ribbons have a curvature that differs from cylindrical curvature of helical ribbons, and no evolution towards closed chiral aggregates was observed. The twisted ribbons may be stable and the chirality can be continuously varied.

The effect of shear on the three regions of the phase diagram concerning micelle transition in surfactant mixtures was investigated using a small-angle neutron scattering technique. The three regions concerned are the vesicle phase, the coexisting vesicle-micelle phase and the supposed worm-like micellar phase. Experimental results showed that an increase in temperature and/or the addition of cetyltrimethylammonium bromide stimulates a vesicle to micelle transition.

The rotational-state-selected CH (v = 0, J, Fi) beam has been prepared by using an electric hexapole and applied to the crossed beam reaction of CH (v = 0, J, Fi) + O2 → OH (A) + CO at different O2 beam conditions. The rotational state selected reactive cross sections of CH (RSSRCS-CH) turn out to depend remarkably on the rotational state distribution of O2 molecules at a collision energy of ∼ 0.19 eV. The reactivity of CH molecules in the N = 1 rotational states (namely |J = 1/2, F2> and |J = 3/2, F1> states, N designates the angular momentum excluding spin) becomes strongly enhanced upon a lowering of the rotational temperature of the O2 beam. The RSSRCS-CH in these two rotational states correlate linearly with the population of O2 molecule in the specific KO2 frame rotation number states: CH(|J=1/2,F2>) with O2(|KO2=1>);CH(|J=3/2,F1>) with O2(|KO2=3>).These linear correlations mean that the rotational-state-selected CH molecules are selectively reactive upon the incoming O2 molecules in a specific rotational state; here, we use the term 'rotationally correlated reactivity' to such specific reactivity depending on the combination of the rotational states between two molecular reactants. In addition, the steric asymmetry in the oriented CH (|J = 1/2, F2, M = 1/2>) + O2 (|KO2=1>) reaction turns out to be negligible (< ±1%). This observation supports the reaction mechanism as theoretically predicted by Huang et al. [J. Phys. Chem. A 106, 5490 (2002)] that the first step is an intermediate formation with no energy barrier in which C-atom of CH molecule attacks on one O-atom of O2 molecule at a sideways configuration. [ABSTRACT FROM AUTHOR]

Steric effect for the XeBr* (B, C) formation in the oriented Xe*(3P2, MJ=2)+oriented CF3Br reaction has been observed as a function of the mutual configuration between the molecular orientation and the atomic orientation in the collision frame. Molecular steric opacity function has been determined as a function of the atomic orbital alignment (LZ′) in the collision frame. The LZ′ selectivity in the molecular steric opacity function is different between the XeBr* (B, C) channels: For the XeBr* (C) channel, the LZ′=0 alignment is favorable at the molecular axis direction and the |LZ′|=1 alignment is favorable at the sideway direction, whereas for the XeBr* (B) channel, the LZ′=0 alignment is favorable at the sideway direction and the |LZ′|=1 alignment is favorable at the molecular axis direction. However, the shape of the steric opacity function for the XeBr* (B) channel at the LZ′=0 (and |LZ′|=1) alignment is similar to that for the XeBr* (C) channel at the |LZ′|=1 (and LZ′=0) alignment, respectively: A large molecular orientation dependence (i.e., the largest reactivity at the Br-end with the small molecular alignment dependence) is recognized for the XeBr* (B) channel at the LZ′=0 alignment and for the XeBr* (C) channel at the |LZ′|=1 alignment, whereas a large molecular alignment dependence (i.e., the largest reactivity at the Br-end with the poor reactivity at the sideway) is recognized for the XeBr* (B) channel at the |LZ′|=1 alignment and for the XeBr* (C) channel at the LZ′=0 alignment. We propose the indirect mechanism for the dark channels (Xe+Br+CF3) via the back-electron transfer from the CF3 segment (or dissociating CF3...Br-) to Xe+ as the origin of the significant molecular alignment dependence in the molecular steric opacity function. [ABSTRACT FROM AUTHOR]

Changes to mean sea level and/or sea level extremes (e.g., storm surges) will lead to changes in coastal impacts. These changes represent a changing exposure or risk to our society. Here, we present 21st century sea-level projections for Norway largely based on the Fifth Assessment Report from the Intergovernmental Panel for Climate Change (IPCC AR5). An important component of past and present sea-level change in Norway is glacial isostatic adjustment. We therefore pay special attention to vertical land motion, which is constrained using new geodetic observations with improved spatial coverage and accuracies, and modelling work. Projected ensemble mean 21st century relative sea-level changes for Norway are, depending on location, from -0.10 to 0.30 m for emission scenario RCP2.6; 0.00 to 0.35 m for RCP 4.5; and 0.15 to 0.55 m for RCP8.5. For all RCPs, the projected ensemble mean indicates that the vast majority of the Norwegian coast will experience a rise in sea level. Norway's official return heights for extreme sea levels are estimated using the average conditional exceedance rate (ACER) method. We adapt an approach for calculating sea level allowances for use with the ACER method. All the allowances calculated give values above the projected ensemble mean Relative Sea Level (RSL) rise, i.e., to preserve the likelihood of flooding from extreme sea levels, a height increase above the most likely RSL rise should be used in planning. We also show that the likelihood of exceeding present-day return heights will dramatically increase with sea-level rise. [ABSTRACT FROM AUTHOR]