Extending K-Scope Fortran Source Code Analyzer with Visualization of Performance Profiling Data and Remote Parsing of Source Code

In estimates of climate sensitivity obtained from global models, the need to represent clouds introduces a great deal of uncertainty. To address this issue, approaches using a high-resolution global non-hydrostatic model are promising: the model captures cloud structure by explicitly simulating meso-scale convective systems, and the results compare reasonably well with satellite observations. We review the outcomes of a 5-year project aimed at reducing the uncertainty in climate models due to cloud processes using a global non-hydrostatic model. In our project, which was conducted as a subgroup of the Program for Risk Information on Climate Change, or SOUSEI, we use the non-hydrostatic icosahedral atmospheric model (NICAM) to study cloud processes related to climate change. NICAM performs numerical simulations with much higher resolution (about 7 km or 14 km mesh) than conventional global climate models (GCMs) using cloud microphysics schemes without a cumulus parameterization scheme, which causes uncertainties in climate projection.The subgroup had three research targets: analyzing cloud changes in global warming simulations with NICAM with the time-slice approach, sensitivity of the results to the cloud microphysics scheme employed, and evaluating circulation changes due to global warming. The research project also implemented a double-moment bulk cloud microphysics scheme and evaluated its results using satellite observation, as well as comparing it with a bin cloud microphysics scheme. The future projection simulations show in general increase in high cloud coverage, contrary to results with other GCMs. Changes in cloud horizontal-size distribution size and structures of tropical/extratropical cyclones can be discussed with high resolution simulations. At the conclusion of our review, we also describe the future prospects of research for global warming using NICAM in the program that followed SOUSEI, known as TOUGOU.

Abstract. Recent advances in high-performance computers facilitate operational numerical weather prediction by global hydrostatic atmospheric models with horizontal resolutions of ∼ 10 km. Given further advances in such computers and the fact that the hydrostatic balance approximation becomes invalid for spatial scales < 10 km, the development of global nonhydrostatic models with high accuracy is urgently required. The Global 7 km mesh nonhydrostatic Model Intercomparison Project for improving TYphoon forecast (TYMIP-G7) is designed to understand and statistically quantify the advantages of high-resolution nonhydrostatic global atmospheric models to improve tropical cyclone (TC) prediction. A total of 137 sets of 5-day simulations using three next-generation nonhydrostatic global models with horizontal resolutions of 7 km and a conventional hydrostatic global model with a horizontal resolution of 20 km were run on the Earth Simulator. The three 7 km mesh nonhydrostatic models are the nonhydrostatic global spectral atmospheric Double Fourier Series Model (DFSM), the Multi-Scale Simulator for the Geoenvironment (MSSG) and the Nonhydrostatic ICosahedral Atmospheric Model (NICAM). The 20 km mesh hydrostatic model is the operational Global Spectral Model (GSM) of the Japan Meteorological Agency. Compared with the 20 km mesh GSM, the 7 km mesh models reduce systematic errors in the TC track, intensity and wind radii predictions. The benefits of the multi-model ensemble method were confirmed for the 7 km mesh nonhydrostatic global models. While the three 7 km mesh models reproduce the typical axisymmetric mean inner-core structure, including the primary and secondary circulations, the simulated TC structures and their intensities in each case are very different for each model. In addition, the simulated track is not consistently better than that of the 20 km mesh GSM. These results suggest that the development of more sophisticated initialization techniques and model physics is needed to further improve the TC prediction.

Analysis of the source code of video games is not an integrated part of the formal analysis. Rather, few scholars have investigated how an analysis of the source code can inform a hermeneutic reading of the game. In this paper I will present a reading of the source code of Passage (Rohrer, 2007), argue for why a traditional focus on authorial intention is unnecessary when investigating the symbolism and metaphors of a game, and illustrate how source code analysis can inform the formal analysis of the executed game. Finally, I shall discuss how the source code relates to the game as a ‘work’, and how it can be used for studies of symbolism and metaphors. Thus, I will conclude that it is indeed a valuable method for game studies, although further studies should expand on the textual relation between executed game and source code.

This study aims to improve precipitation forecasts by estimating model parameters of a numerical weather prediction model with an ensemble‐based data assimilation method. We implemented the parameter estimation algorithm into a global atmospheric data assimilation system NICAM‐LETKF, which incorporates Nonhydrostatic Icosahedral Atmospheric Model (NICAM) and the Local Ensemble Transform Kalman Filter (LETKF). This study estimated a globally uniform model parameter of a large‐scale condensation scheme known as the B1 parameter of Berry's parameterization. We conducted an online estimation of the B1 parameter using the Global Satellite Mapping of Precipitation (GSMaP) data and successfully reduced NICAM's precipitation forecast bias relative to the GSMaP data, especially for weak rains. The estimated B1 parameter evolved toward the optimal value obtained by manual tuning. The parameter estimation also mitigated a dry bias for the lower troposphere in the Tropics. However, the estimated B1 intensified biases for cloud water mixing ratio and outgoing long‐wave radiation in the regions where shallow clouds are dominant. This is because only precipitation data were used to estimate the optimal value of B1, and more constraints will be required to obtain a suitable value for climatological simulations.

We studied the semi-diurnal variation of surface rainfall over southern Africa and the Amazon simulated by a global cloud system resolving model (Nonhydrostatic ICosahedral Atmospheric Model; NICAM) under realistic conditions with land-sea contrast. This semi-diurnal variation was found to be consistent with the Tropical rainfall Measuring Mission (TRMM) and Meteosat-8 observations. The timing of the primary afternoon rainfall peak by the NICAM coincides with TRMM/PR primary afternoon peak, and the secondary early morning peak by the NICAM simulation agree with the TRMM/PR observations within two hours. Mean size of deep convection (DC), defined by 213K of the Meteosat-8 infrared data shows semi-diurnal variation, although the number of DC show diurnal variation with coincident peak with TRMM/PR primary peak. The semi-diurnal variation of the mean size of DC and number of DC is simulated with small secondary peak over southern Africa by NICAM, whose DC is defined by OLR smaller than 112 W m-2 (corresponding to 213 K in cumulative frequency).

<p>The Non-hydrostatic ICosahedral Atmospheric Model (NICAM), a global model with an icosahedral grid system, has been under development for nearly two decades. Here, we present its recent updates for the Coupled Model Intercomparison Project Phase 6, High Resolution Model Intercomparison Project (HighResMIP) and their impact on the simulated mean states using 56-14km mesh model. Major updates include updates of the cloud microphysics scheme and land surface model, introduction of natural and anthropogenic aerosols and a subgrid-scale orographic gravity wave drag scheme, and improvement of the coupling between the cloud microphysics and the radiation schemes. A short-term sensitivity experiments demonstrate improvements in the ice water content, high cloud amount, surface air temperature over the Arctic region, location and strength of zonal mean subtropical jet, and shortwave radiation over Africa and South Asia. The decadal climate simulations further reveal an improvement in the genesis and structure of the tropical cyclones compared with those with the previous model. Finally, we will address outlook toward the cloud-resolving climate simulation based on a fresh benchmark result on supercomputer Fugaku, a flagship supercomputer in Japan.</p>

The Madden–Julian oscillation (MJO) is the most predominant tropical intraseasonal variability and is a source of modulating global weather patterns. An accurate simulation of the MJO still remains a challenge for general circulation models (GCMs), and in fact, climate simulations with GCMs often struggle with the mean state-variability tradeoff. For this issue, a global storm-resolving climate simulation, which a recent increase in computing power makes possible, is expected to be a useful way because of its merit of direct coupling between moist processes and dynamics. The present study examines the MJO representation in an AMIP-type ~10-year simulation with the Nonhydrostatic Icosahedral Atmospheric Model (NICAM) at 3.5-km horizontal resolution, in comparison with that in one of conventional GCMs (MIROC6). This NICAM simulation successfully reproduces the realistic initiation frequency, propagation, and hierarchical structure of MJO convection, as well as realistic mean states (e.g., mean tropical precipitation), whereas MIROC6 overly underestimates the number of robust MJO events, and the activity of westward-propagating synoptic-scale waves embedded within MJO convective envelopes. As specific processes, the enhanced mixed Rossby-gravity wave-like systems seem to be a precursor and building blocks of the MJO simulated with NICAM at least over the Indian Ocean, consistent with several observational studies. In addition, NICAM-MJO propagation into the western Pacific is helped by high-frequency intermittent advective moistening that can be triggered by the upper-tropospheric PV intrusion from the extratropics. This feature is also found in some of observed MJO events. Our results suggest that good MJO simulations can attribute to representing the feedback from a complex of synoptic-scale waves onto MJO convective envelopes appropriately, and that the extratropics sometimes plays an active role in MJO dynamics. A success in simulating and scrutinizing these cross-scale interactions about the MJO is one of clear merits of kilometer-scale climate simulations without the assumption of a priori scale separation and quasi-equilibrium characteristics.

Recent increase in computation power allows a use of high-resolution global model to investigate possible future change of tropical cyclones. In this chapter, we propose a new approach here to pursue the issue: the use of global cloud- system resolving model (GCRM).1 It is the model designed with the clear aim of resolving cloud cluster, an essential component of tropical cyclogenesis, and therefore expected to provide a new result for the projection of future change of tropical cyclone. This chapter highlights our first attempt of time-slice prediction of future tropical cyclone (TC) under a global warming condition and associated climate change of season-long period with 14-km mesh version of Nonhydrostatic ICosahedral Atmospheric Model (NICAM), a prototype GCRM. Notable changes in the seasonal-mean state include decrease in outgoing longwave radiation (OLR) in the western to central Pacific, in particular east of the maritime continent, and increase in OLR and decrease in outgoing shortwave radiation in the mid and high latitudes. The former (the latter) is associated with an enhanced activity of precipitation (decrease in cloud amount) over the region. Global frequency of TCs in the seasonal period is projected to decrease, in agreement with the general statement in the Intergovernmental Panel on Climate Change Fourth Assessment Report. On a regional basis, the frequency decreases over the North Atlantic, and remains almost unchanged in the western Pacific. The tendency of global frequency is found to be insensitive to detection threshold of the surface wind speed in the tropical cyclone tracking algorithm. The control experiment is designed for the particular year of 2004, which had a more El Nino flavor than normal year; therefore some caution is necessary in interpreting the results for this particular choice of experimental design.

<p>Recent advancement of supercomputing enables us to conduct a climate simulation by using a global model with horizontal grid spacing of a few kilometers. We may need to tune the model in order to conduct a reliable simulation. In order to test feasibility of a few kilometer climate simulation in near future, we conducted one-year simulation from June 2004 to May 2005 by using Nonhydrostatic Icosahedral Atmospheric Model (NICAM) with horizontal grid spacing of 28 km, 14 km, 7 km, and 3.5 km, and evaluated their simulation performances. In general, global models have shown weak wind speed of tropical cyclones compared to its central sea level pressure due to insufficient horizontal resolution. As expected, the 3.5 km simulation showed improvement of this bias. As for simulated mean state, globally annual mean precipitation tended to be decreased with finer horizontal resolution in NICAM. Compared with observation (Global Precipitation Climatology Project V2.2; 2.71 mm day<sup>-1</sup>), 7 km and 3.5 km simulations underestimated the global mean precipitation (2.54 mm day<sup>-1</sup> and 2.67 mm day<sup>-1</sup>), while 14 km and 28 km simulations overestimated (2.84 mm day<sup>-1</sup> and 2.78 mm day<sup>-1</sup>). The 3.5 km simulation showed the best performance for reproducing globally annual mean precipitation. However, the 3.5 simulation showed underestimation of the South Pacific Convergence Zone. In order to conduct a reliable simulation, we need to improve performance of the 3.5 km global model. This demands extensive computing resources. The supercomputer Fugaku will give us extensive computing resources for addressing this issue.</p>

This article reviews the development of a global non-hydrostatic model, focusing on the pioneering research of the Non-hydrostatic Icosahedral Atmospheric Model (NICAM). Very high resolution global atmospheric circulation simulations with horizontal mesh spacing of approximately O (km) were conducted using recently developed supercomputers. These types of simulations were conducted with a specifically designed atmospheric global model based on a quasi-uniform grid mesh structure and a non-hydrostatic equation system. This review describes the development of each dynamical and physical component of NICAM, the assimilation strategy and its related models, and provides a scientific overview of NICAM studies conducted to date.

A nonhydrostatic stretched-grid (SG) model is used to analyze the large-scale errors generated by stretching horizontal grids and their influence on a region of interest. Simulations by a fully compressible, nonhydrostatic global atmospheric model, the Nonhydrostatic Icosahedral Atmospheric Model (NICAM), and its SG regional model, stretched-NICAM, were performed for the months of March, April, and May of 2011 using various resolutions and stretching factors. A comparison of week-long accumulative precipitation amounts between the Tropical Rainfall Measuring Mission (TRMM) satellite data and the quasi-uniform and SG simulations showed that a stretched run better represents storms and associated precipitation because the errors generated in the outer regions with coarser grid spacing do not significantly affect the inner domain centered at the focal point. For season-long simulations, in one particular set of stretched runs with the focal point located in the eastern United States, the artificial suppression of baroclinic development of midlatitude eddies in the Southern Hemisphere weakened the eddy-driven polar-front jet (PFJ), which yielded a cold bias at mid- to high latitudes. However, in the Northern Hemisphere, in contrast, the aforementioned changes are less apparent. Therefore, for the SG runs, the mean temperature was maintained at the region of interest, and an increased amount of moderate to heavy precipitation, which is also frequently found in the TRMM data, was observed; thus, the benefits of increased resolution were realized. However, careful attention must be given when applying the SG model because a regional climate response to the change in the large-scale circulations may not be fully accounted for.

Static code analysis is a very important stage in the development and implementation of software, and it needs to be used to obtain a better code. The most complicated in static analysis is the analysis of source code, and further analysis. Analysis of the source code can be done multiple times and expand the set of necessary grammar. The main goal was and remains to provide a solution to reduce the time needed for a global reassessment of static analysis at code level after a change.The main problem when using static code analysis is to build an abstract semantic graph, because each software solution is provided with a separate data warehouse. The proposed solution proposes to use as a database repository using graphs. Thus, the storage mechanisms of the created abstract semantic graph have been simplified, which in turn, in addition to increasing the clarity of the information we store, provides convenient ways to further work with the stored information.The developed solution can transform a rather large source repository into a graphic representation and maintain it later. It is found that the approach is suitable for carrying out code compliance checks and for performing static analysis tests on a graphic representation. This approach also uses advanced file-level detailing, accelerating static analysis. Based on my measurements, the frameworks are fast enough to help their users quickly change the repository of codes.This article confirms the thesis about the possibility of storing an abstract semantic graph in a graph database, and after refinement, if it contains sufficient transformations and requests for language processing, can become a complete transport for communication between various static analysis tools that usually perform one of two the functions of verification either for quality or for vulnerability, thereby making a unified creation of an abstract semantic graph.As an improvement it is necessary to consider the possibility of incremental analysis – the analysis of changes in the code, in order to minimize resource costs for a rather resource intensive operation of the structure of the abstract semantic graph.Manuscript received 09.06.2020

A high-performance computing resource allows us to conduct numerical simulations with a horizontal grid spacing that is sufficiently high to resolve cloud systems. The cutting-edge computational capability, which was provided by the K computer at RIKEN in Japan, enabled the authors to perform long-term, global simulations of air pollutions and clouds with unprecedentedly high horizontal resolutions. In this study, a next generation model capable of simulating global air pollutions with O(10 km) grid spacing by coupling an atmospheric chemistry model to the Non-hydrostatic Icosahedral Atmospheric Model (NICAM) was performed. Using the newly developed model, month-long simulations for July were conducted with 14 km grid spacing on the K computer. Regarding the global distributions of aerosol optical thickness (AOT), it was found that the correlation coefficient (CC) between the simulation and AERONET measurements was approximately 0.7, and the normalized mean bias was -10%. The simulated AOT was also compar...

This study investigates the potential impacts of frequent global coverage of satellite microwave radiances using a global atmospheric data assimilation (DA) system. Observing Systems Simulation Experiments (OSSEs) were performed using the Local Ensemble Transform Kalman Filter with the Nonhydrostatic Icosahedral Atmospheric Model (NICAM). Three different observation time intervals are examined: hourly (1H), bi‐hourly (2H), and six‐hourly (6H). 6H mimics the current coverage of Advanced Microwave Sounding Unit‐A in orbits. 1 and 2H show higher Root Mean Square Errors (RMSEs) for temperature compared to 6H due to dynamical imbalances indicated by the second time derivatives of sea level pressure. To mitigate the imbalances in 1H, we first inflate the observation error standard deviation in DA by 60% (1H‐Rinfl) and successfully reduce imbalances by 5%–10% with the temperature RMSE decreased by 10%–15%. Next, we apply the Adaptive Observation Error Inflation (AOEI) method, which adjusts the observation error standard deviations online based on the innovation statistics. 1H with AOEI (1H‐AOEI) reduces the dynamical imbalance and shows lower RMSE than that of 6H. 1H‐AOEI also shows more skill in forecasting precipitation events with intensity >2 mm/hr on small scales than 6H.

The 2018 tropical cyclone (TC) season in the North Pacific was very active, with 39 tropical storms including eight typhoons/hurricanes. This activity was successfully predicted up to 5 months in advance by the Geophysical Fluid Dynamics Laboratory Forecast‐Oriented Low Ocean Resolution (FLOR) global coupled model. In this work, a suite of idealized experiments with three dynamical global models (FLOR, Nonhydrostatic Icosahedral Atmospheric Model, and Meteorological Research Institute Atmospheric General Circulation Model) was used to show that the active 2018 TC season was primarily caused by warming in the subtropical Pacific and secondarily by warming in the tropical Pacific. Furthermore, the potential effect of anthropogenic forcing on the active 2018 TC season was investigated using two of the global models (FLOR and Meteorological Research Institute Atmospheric General Circulation Model). The models projected opposite signs for the changes in TC frequency in the North Pacific by an increase in anthropogenic forcing, thereby highlighting the substantial uncertainty and model dependence in the possible impact of anthropogenic forcing on Pacific TC activity.