We describe Global Atmosphere 3.0 (GA3.0): a configuration of the Met Office Unified Model (MetUM) developed for use across climate research and weather prediction activities. GA3.0 has been ...formulated by converging the development paths of the Met Office's weather and climate global atmospheric model components such that wherever possible, atmospheric processes are modelled or parametrized seamlessly across spatial resolutions and timescales. This unified development process will provide the Met Office and its collaborators with regular releases of a configuration that has been evaluated, and can hence be applied, over a variety of modelling régimes. We also describe Global Land 3.0 (GL3.0): a configuration of the JULES community land surface model developed for use with GA3.0. This paper provides a comprehensive technical and scientific description of the GA3.0 and GL3.0 (and related GA3.1 and GL3.1) configurations and presents the results of some initial evaluations of their performance in various applications. It is to be the first in a series of papers describing each subsequent Global Atmosphere release; this will provide a single source of reference for established users and developers as well as researchers requiring access to a current, but trusted, global MetUM setup.
We describe Global Atmosphere 4.0 (GA4.0) and Global Land 4.0 (GL4.0): configurations of the Met Office Unified Model and JULES (Joint UK Land Environment Simulator) community land surface model ...developed for use in global and regional climate research and weather prediction activities. GA4.0 and GL4.0 are based on the previous GA3.0 and GL3.0 configurations, with the inclusion of developments made by the Met Office and its collaborators during its annual development cycle. This paper provides a comprehensive technical and scientific description of GA4.0 and GL4.0 as well as details of how these differ from their predecessors. We also present the results of some initial evaluations of their performance. Overall, performance is comparable with that of GA3.0/GL3.0; the updated configurations include improvements to the science of several parametrisation schemes, however, and will form a baseline for further ongoing development.
The Southern Ocean is a critical region for global climate, yet large cloud and solar radiation biases over the Southern Ocean are a long-standing problem in climate models and are poorly understood, ...leading to biases in simulated sea surface temperatures. This study shows that supercooled liquid clouds are central to understanding and simulating the Southern Ocean environment. A combination of satellite observational data and detailed radiative transfer calculations is used to quantify the impact of cloud phase and cloud vertical structure on the reflected solar radiation in the Southern Hemisphere summer. It is found that clouds with supercooled liquid tops dominate the population of liquid clouds. The observations show that clouds with supercooled liquid tops contribute between 27% and 38% to the total reflected solar radiation between 40° and 70°S, and climate models are found to poorly simulate these clouds. The results quantify the importance of supercooled liquid clouds in the Southern Ocean environment and highlight the need to improve understanding of the physical processes that control these clouds in order to improve their simulation in numerical models. This is not only important for improving the simulation of present-day climate and climate variability, but also relevant for increasing confidence in climate feedback processes and future climate projections.
We analyze horizontal transport from midlatitudes into the tropics (in‐mixing) and its impact on seasonal variations of ozone, carbon monoxide and water vapor in the Tropical Tropopause Layer (TTL). ...For this purpose, we use three‐dimensional backward trajectories, driven by ECMWF ERA‐Interim winds, and a conceptual one‐dimensional model of the chemical composition of the TTL. We find that the fraction of in‐mixed midlatitude air shows an annual cycle with maximum during NH summer, resulting from the superposition of two inversely phased annual cycles for in‐mixing from the NH and SH, respectively. In‐mixing is driven by the monsoonal upper‐level anticyclonic circulations. This circulation pattern is dominated by the Southeast Asian summer monsoon and, correspondingly, in‐mixing shows an annual cycle. The impact of in‐mixing on TTL mixing ratios depends on the in‐mixed fraction of midlatitude air and on the meridional gradient of the particular species. For CO the meridional gradient and consequently the effect of in‐mixing is weak. For water vapor, in‐mixing effects are negligible. For ozone, the meridional gradient is large and the contribution of in‐mixing to the ozone maximum during NH summer is about 50%. This in‐mixing contribution is not sensitive to the tropical ascent velocity, which is about 40% too fast in ERA‐Interim. As photochemically produced ozone in the TTL shows no distinct summer maximum, the ozone annual anomaly in the upper TTL turns out to be mainly forced by in‐mixing of ozone‐rich extratropical air during NH summer.
Key Points
Horizontal transport affects O3 annual cycle in TTL ‐ H2O and CO unaffected
Horizontal transport into TTL is driven by monsoon anticyclones
At least 30% summer O3 and 65% annual amplitude linked to horizontal transport
Bacteriophage-encoded endolysins have been identified as antibacterial candidates. However, the development of endolysins as mainstream antibacterial agents first requires a comprehensive biochemical ...understanding. This study defines the atomic structure and enzymatic function of
O157:H7 phage FAHEc1 endolysin, LysF1. Bioinformatic analysis suggests this endolysin belongs to the T4 Lysozyme (T4L)-like family of proteins and contains a highly conserved catalytic triad. We then solved the structure of LysF1 with x-ray crystallography to 1.71 Å. LysF1 was confirmed to exist as a monomer in solution by sedimentation velocity experiments. The protein architecture of LysF1 is conserved between T4L and related endolysins. Comparative analysis with related endolysins shows that the spatial orientation of the catalytic triad is conserved, suggesting the catalytic mechanism of peptidoglycan degradation is the same as that of T4L. Differences in the sequence illustrate the role coevolution may have in the evolution of this fold. We also demonstrate that by mutating a single residue within the hydrophobic core, the thermal stability of LysF1 can be increased by 9.4 °C without compromising enzymatic activity. Overall, the characterization of LysF1 provides further insight into the T4L-like class of endolysins. Our study will help advance the development of related endolysins as antibacterial agents, as rational engineering will rely on understanding mutable positions within this protein fold.
Effects of plant height on Fusarium crown rot (FCR) disease severity were investigated using 12 pairs of near-isogenic lines (NILs) for six different reduced height (Rht) genes in wheat. The dwarf ...isolines all gave better FCR resistance when compared with their respective tall counterparts, although the Rht genes involved in these NILs are located on several different chromosomes. Treating plants with exogenous gibberellin increased FCR severity as well as seedling lengths in all of the isolines tested. Analysis of the expression of several defense genes with known correlation with resistance to FCR pathogens between the Rht isolines following FCR inoculation indicated that the better resistance of the dwarf isolines was not due to enhanced defense gene induction. These results suggested that the difference in FCR severity between the tall and dwarf isolines is likely due to their height difference per se or to some physiological and structural consequences of reduced height. Thus, caution should be taken when considering to exploit any FCR locus located near a height gene.
We present an analysis of two deep (75 ks) Chandra observations of the European Large Area Infrared Space Observatory (ISO) Survey (ELAIS) fields N1 and N2 as the first results from the ELAIS deep ...X-ray survey. This survey is being conducted in well-studied regions with extensive multiwavelength coverage. Here we present the Chandra source catalogues along with an analysis of source counts, hardness ratios and optical classifications. A total of 233 X-ray point sources are detected in addition to two soft extended sources, which are found to be associated with galaxy clusters. An overdensity of sources is found in N1 with 30 per cent more sources than N2, which we attribute to large-scale structure. A similar variance is seen between other deep Chandra surveys. The source count statistics reveal an increasing fraction of hard sources at fainter fluxes. The number of galaxy-like counterparts also increases dramatically towards fainter fluxes, consistent with the emergence of a large population of obscured sources.
WT1
is a thermophilic, peptide, and amino acid-fermenting archaeon from the order
. It was isolated from Waiotapu, Aotearoa-New Zealand, and has a genome size of 1.80 Mbp. The genome contains 2,000 ...total genes, of which 1,913 encode proteins and 46 encode tRNA.
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