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Cloud-radiative heating (CRH) within the atmosphere and its changes with warming affect the large-scale atmospheric wind patterns in a myriad of ways, such that reliable predictions and projections of circulation require reliable calculations of CRH. In order to assess sensitivities of upper-tropospheric midlatitude CRH to model settings, we perform a series of simulations with the Icosahedral Nonhydrostatic Model (ICON) over the North Atlantic using six different grid spacings, parameterized and explicit convection, and one- versus two-moment cloud microphysics. While sensitivity to grid spacing is limited, CRH profiles change dramatically with microphysics and convection schemes. These dependencies are interpreted via decomposition into cloud classes and examination of cloud properties and cloud-controlling factors within these different classes. We trace the model dependencies back to differences in the mass mixing ratios and number concentrations of cloud ice and snow, as well as vertical velocities. Which frozen species are radiatively active and the coupling of microphysics and convection schemes turn out to be crucial factors in altering the modeled CRH profiles. [ABSTRACT FROM AUTHOR]

Introduction: Thalassaemia is one of the most common genetic disorders. Iron overload due to repeated blood transfusions and chelating therapy leads to oxidative stress and possible irreversible brain tissue damage, causing cognitive impairment in these children. Aim: To study cognitive impairment in children with beta thalassaemia major in a tertiary care centre in Bikaner, Rajasthan, India. Materials and Methods: This was a hospital-based crosssectional observational study conducted in the Department of Paediatrics, Sardar Patel Medical College, Bikaner, Rajasthan, India from September 2019 to August 2020. Sixty-five children with thalassaemia and 65 children without thalassaemia (as controls) were recruited and assessed using modified Mini-Mental State Examination (MMSE) for cognitive impairment. Results: Majority of children belonged to age group 6-11 years (67.7% in cases and 68.8% in controls). The mean MMSE scores were significantly lower among children with thalassaemia (26.82±6.45) compared to the controls (29.08±5.71). There was a significantly higher prevalence of cognitive dysfunction in thalassaemia children (72.3%) as compared to controls (33.8%). Children who were compliant with chelation medications (n=30) were found to have a lesser prevalence of cognitive dysfunction (60%) than those who were not compliant (n=35) with medications (82.86%) (p-value=0.013). Among cases, the mean ferritin levels were higher in children with cognitive dysfunction (3399.00±1489.18) compared to those with normal cognitive function (2412.38±1117.26) (p-value=0.046). There was moderate positive correlation between thalassaemia child's Body Mass Index (BMI) and modified MMSE score. Conclusion: This study highlights the higher prevalence of cognitive impairment in children with thalassaemia (72.3%). The key contributing factors were-lack of compliance to chelation therapy, higher serum ferritin levels and low BMI. [ABSTRACT FROM AUTHOR]

Warm conveyor belts are important features of extratropical cyclones and are characterized by active diabatic processes. Previous studies reported that the simulation of extratropical cyclones can be strongly impacted by horizontal model resolution. Here, we study to what extent and in which manner simulations of warm conveyor belts are impacted by model resolution. To this end we investigate the warm conveyor belt of the North Atlantic cyclone Vladiana that occured around 23 September 2016 and was observed as part of the North Atlantic Waveguide and Downstream Impact Experiment.We analyze a total of 18 limited-area simulations with the ICOsahedral Nonhydrostatic model run over the North Atlantic that cover a range of horizontal resolutions from 80 to 2.5 km, including the resolution of current low-resolution global climate models with parametrized convection as well as the resolution of future storm-resolving climate models with explicit convection. The simulations also test the sensitivity with respect to the representation of convection and cloud microphysics.With higher resolution, the number of WCB trajectories increases systematically and a new class of anticyclonic trajectories emerges that is absent at the lowest resolution of 80 km. WCB trajectories ascend faster and higher as resolution is increased. Explicitly resolving convection increases these changes further.We also diagnose the impact of increased resolution on the ascent velocity and vorticity of WCB air parcels and the diabatic heating that these parcels experience.With increasing resolution, ascent velocity increases at all pressure levels by around a factor of 3 and vorticity increases similarly strongly in the lower and middle troposphere. We find a corresponding increase in diabatic heating as resolution is refined, arising mainly from cloud-associated phase changes of water. Besides resolution, the treatment of convection has a stronger impact than the treatment of cloud microphysics in our simulations. We find no clear connection between the strength of diabatic heating within the WCB on the one hand and the deepening of cyclone Vladiana in terms of its central pressure on the other hand. An analysis of the pressure tendency equation shows that this is because diabatic heating plays a minor role for the deepening of the cyclone, which is dominated by temperature advection [ABSTRACT FROM AUTHOR]

Regional climate models (RCMs) serve as an important tool to perform high resolution climate simulations for a limited area. However, there remains a crucial issue regarding the efficacy of RCMs that whether they are able to produce added value (AV) in representing the regional climatic features compared to their coarse scale driving Global climate models (GCMs). The present study aims at assessing the AV of a set of RCM simulations performed under the Coordinated Regional Climate Downscaling Experiments‐South Asia (CORDEX‐SA) compared with their respective driving GCMs in representing the Indian summer monsoon (ISM) precipitation and its dynamical features. For this purpose, the performance of RCMs and GCMs is compared for the present day climate (1970–2005) against observations and reanalysis datasets in terms of various ISM features, that is, the spatial distribution of precipitation, the evolution of vertical shear of zonal wind and the onset phase of ISM in terms of delayed or early arrival of monsoon. The RCMs show a clear improvement upon their corresponding driving GCMs in simulating spatial features of precipitation distribution that are characteristically associated with ISM. Regionally, the RCMs also show skill in capturing the precipitation amount as a reduction in bias is found compared with their driving GCMs. There is a significant improvement in the simulation of onset dates of ISM by only some of the experiments particularly, RegCM4 driven with IPSL‐CM5A‐LR. The study concludes that the present set of CORDEX‐SA RCM simulations do indeed add value to their driving GCMs for a number of features associated with the ISM precipitation but this value varies with region, driving GCM and the particular feature of ISM under focus. Simulated climatology (1970–2005) of JJAS mean precipitation (mm day−1) by (A) IMD observation, (a1–l1) GCMs and their corresponding (a2–l2) CORDEX‐SA RCMs grouped together in a box. The orographic feature in spatial variability of ISM is evident in IMD—a characteristic which seems to be better captured here by RCMs as compared to their parent GCMs. [ABSTRACT FROM AUTHOR]

Indus River Basin (IRB) in the western Himalayas is very important for the sustainability of livelihood, food and water security of its inhabitants. In the present work, changing climate and its impact on water budget of IRB is discussed. For this, simulation from a regional climate model (REMO) is studied for present (1970–2005) and future (till 2099) climate under various representative concentration pathways (RCPs). It is distinctly seen that, there is a likely increased (decreased) precipitation over upper (lower) IRB under both the RCPs. Moreover, a heterogeneous warming pattern is projected over the region with season‐specific response of warming towards increasing greenhouse gases (GHGs). Higher (lower) evapotranspiration over the lower (central) IRB raise serious concerns about water issues. The changes in climatic parameters will have huge impact on the associated water budget. Linkages of water budget with the corresponding precipitation, temperature, evapotranspiration and runoff provide possible mechanisms for depleting (enhancing) water storage over the lower (upper) IRB during DJF (JJAS). This will have impact on agriculture, crop and water security of the region and thus underlines the need for adaptation policies at governance level. (A) Trend of seasonal mean precipitation (mm day−1 year−1) during 1970–2099 over Indus River Basin (IRB) from regional climate model (REMO) regional model driven by MPI‐ESM‐LR global model under CORDEX‐SA, under RCP2.6 (a–d) and RCP8.5 (e–h) for DJF, MAM, JJAS and ON seasons. (B) Time series of precipitation (mm/day) averaged over the same. The series in grey corresponds to observation data (APHRODITE) for the period 1970–2005. The series in blue, green and red correspond to Present (1970–2005), RCP2.6 and RCP8.5 warming scenarios (2006–2099), respectively, from REMO regional model forced with MPI‐ESM‐LR global model. [ABSTRACT FROM AUTHOR]