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Ice clouds are a major source of uncertainty within climate projections. The upcoming Ice Cloud Imager (ICI) mission is designed to address the lack of cloud ice observations contributing to this issue. ICI will measure within a frequency range of 183 GHz to 664 GHz, bridging current gaps in observations. The sub-millimetre wavelengths are particularly suited for interaction with ice hydrometeors. Therefore, ICI will provide reliable global data on cloud ice on a daily basis.Since ICI is the first-of-its-kind, retrieval schemes require rigorous 'all-sky' simulations. However, modelling the cloud-radiation interaction is challenging due to the complex microphysics of ice clouds and the novelty of the wavelengths. The generation of a cloud radiation database will be covered, focusing on radiative transfer calculations. The database contains pairs of simulated observations and atmospheric states, offering global and seasonal coverage. Ice hydrometeors are represented by particle models that combine single scattering data with empirically-based assumptions on size and shape. An approximation to particle orientation is implemented, allowing for polarisation effects to be captured. Atmospheric states capture the three-dimensional variability of cloud structure.The database shows statistical consistency with global radar retrievals (DARDAR). Observations are simulated for airborne (ISMAR) and satellite (GMI) missions and compared to existing observations. Inversions of real observations are performed, and results show realistic spatial distributions.The database is state-of-the-art, containing the most realistic simulations of ICI radiances to date. Post-launch, retrievals will be performed on real ICI measurements, providing valuable data for use within climate monitoring, modelling, and numerical weather prediction., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The temporal evolution of unrejoined and misrejoined DNA double-strand breaks (DSBs) produced by high doses (80-160 Gy) of X rays has been estimated using pulsed-field gel electrophoresis (PFGE) (Löbrich et al., Proc. Natl. Acad. Sci. USA 92, 12050-12054, 1995). We attempted to fit these data to three models. An RBM ("Revell binary misrejoining") model, based on the usual repair-misrepair and lethal-potentially lethal models, appears to be inconsistent with the data. The main discrepancies are the following: (1) The RBM model predicts that 90% of the misrejoined DSBs form by the time 75% of the DSBs have disappeared, while the data indicate that only 50% are formed by this time; and (2) the model predicts an increasing fraction of DSBs misrejoined at 160 Gy compared to 80 Gy, while the data support approximately equal fractions misrejoined. These discrepancies are alleviated in the Sax subset (SS) and Revell subset (RS) models. In the SS and RS models, two types (or subsets) of DSBs exist: those that are active in misrejoining and those that are not. In the SS model, active DSBs misrejoin by the breakage-and-reunion mechanism described by Sax; in the RS model, active DSBs either repair, or misrejoin according to the complete exchange misrejoining mechanism described by Revell. Both models are consistent with the data set considered.