Global Energy Balance Research Articles

Evolution of the role of alternative energy resources and natural gas in the global energy balance

Evolution of the role of alternative energy resources and natural gas in the global energy balance

Linear Galerkin-Legendre spectral scheme for a degenerate nonlinear and nonlocal parabolic equation arising in climatology

A special place in climatology is taken by the so-called conceptual climate models. These relatively simple sets of differential equations can successfully describe single mechanisms of climate. We focus on one family of such models based on the global energy balance. This gives rise to a degenerate nonlocal parabolic nonlinear partial differential equation for the zonally averaged temperature. We construct a fully discrete numerical method that has an optimal spectral accuracy in space and second order in time. Our scheme is based on the Galerkin formulation of the Legendre basis expansion, which is particularly convenient for this setting. By using extrapolation, the numerical scheme is linear even though the original equation is nonlinear. We also test our theoretical results during various numerical simulations that support the aforementioned accuracy of the scheme.

Updating global energy balance based on the latest observations and reanalyses

全球大气顶和地表能量平衡在地球气候变化中起到决定性作用。卫星云和地球辐射能量系统（CERES）可以直接观测大气顶能量平衡各分量，地表能量平衡则需要借助卫星遥感反演和大气再分析进行估计。已有研究需要对一些关键参数做人为调整，结果差异很大。基于高精度地基和卫星观测，评估了新一代大气再分析量化全球能量平衡的能力，基于2015-2020年6年平均，给出全球、陆地和海洋大气顶与地表辐射分量的最优估计，同时结合最新的全球降水观测计划（GPM）产品给出地表潜热通量的最优估计。发现新一代大气再分析中对大气顶反射太阳辐射高估达8 Wm-2；对大气顶出射长波辐射也有10 Wm-2的高估，这种高估在热带海洋上最为显著。欧洲中期天气预报中心第五代大气再分析产品（ERA5）可以很好地再现大气顶能量不平衡量（1.1 Wm-2），其它三个再分析的误差从-10.7 Wm-2到5.4 Wm-2不等。地表入射太阳辐射的最优估计来自CERES卫星产品，为187 Wm-2；地表大气向下长波辐射的最优估计来自ERA5，为342 Wm-2。相对于最新的GPM降水产品，原有全球降水气候计划（GPCP）产品低估全球降水8.4%，主要因为其对海洋上空降水的明显低估。基于GPM降水产品以及入海径流的估计，得到全球、陆地和海洋上地表潜热通量的最优估计分别为83 Wm-2、41 Wm-2和101 Wm-2。本文根据验证结果，给出了地表能量平衡各分量的最优估计，实现了地表能量闭合，不再需要人为调整。

Unevenly distributed CO2 and its impacts on surface energy balance

Atmospheric carbon dioxide (CO2) has affected global surface and atmospheric energy balance since the Industrial Revolution. The spatial distribution of CO2 concentrations derived from satellite observation are introduced into the coupled Beijing Normal University Earth System Model (BNU-ESM) to study the responses of temperature and surface energy balance to non-uniform CO2 distribution under the Representative Concentration Pathway 8.5 scenario to 2100. Global annual mean atmospheric CO2 concentrations are set to equal those specified in the standard uniform CO2 simulations with differences in spatial pattern and seasonal cycles amounting to tens of ppm. Relative to the uniform CO2 simulation, global annual mean surface air temperature increases by 0.44 ± 0.03 °C over 2071–2100 when forced with non-uniformly distributed CO2, in the Arctic by 1.63 ± 0.28 °C and by 0.67 ± 0.08 °C in northern midlatitudes. The non-uniform CO2 simulation increases global surface energy by 0.68 ± 0.06 W m−2, principally due to a 0.73 ± 0.08 W m−2 increase in net downward surface longwave flux. Surface energy balance increases by 0.33 ± 0.11 W m−2 (7.4%) averaged over oceans indicting a significant increase in ocean heat uptake. Surface energy budget averaged over the Arctic summer increases by 0.91 ± 0.68 W m−2 in the non-uniform CO2 simulation, which would have impact on sea ice extent and land ice melt rates with associated feedbacks. The increased surface energy fluxes and temperatures imply reduced time and emission space for greenhouse gases before running into scientific and politically flagged temperature limits.

Calculation of capacity of crusher with stops on a roll

All industrial metallurgical enterprises produce and use milled materials obtained by crushing. In the global energy balance, the share of produced energy consumed for crushing is more than 5 %. This paper considers a scheme of the crusher with stops on a roll, the structure of which forms a complex stress state in a crushed piece under one­time action of normal and tangential stresses. It is shown that when generating a complex stress state in a fragmented piece of brittle material, the energy consumption is less by 30 – 40 % than when acting in a piece of linear normal stress. The authors developed a method for determining capacity of the drive electric motor of an energy-saving crusher with stop on a roll at design stage.

XFEL serial crystallography reveals the room temperature structure of methyl-coenzyme M reductase

Methyl-Coenzyme M Reductase (MCR) catalyzes the biosynthesis of methane in methanogenic archaea, using a catalytic Ni-centered Cofactor F430 in its active site. It also catalyzes the reverse reaction, that is, the anaerobic activation and oxidation, including the cleavage of the CH bond in methane. Because methanogenesis is the major source of methane on earth, understanding the reaction mechanism of this enzyme can have massive implications in global energy balances. While recent publications have proposed a radical-based catalytic mechanism as well as novel sulfonate-based binding modes of MCR for its native substrates, the structure of the active state of MCR, as well as a complete characterization of the reaction, remain elusive. Previous attempts to structurally characterize the active MCR-Ni(I) state have been unsuccessful due to oxidation of the redox- sensitive catalytic Ni center. Further, while many cryo structures of the inactive Ni(II)-enzyme in various substrates-bound forms have been published, no room temperature structures have been reported, and the structure and mechanism of MCR under physiologically relevant conditions is not known. In this study, we report the first room temperature structure of the MCRred1-silent Ni(II) form using an X-ray Free-Electron Laser (XFEL), with simultaneous X-ray Emission Spectroscopy (XES) and X-ray Diffraction (XRD) data collection. In celebration of the seminal contributions of inorganic chemist Dick Holm to our understanding of nickel-based catalysis, we are honored to announce our findings in this special issue dedicated to this remarkable pioneer of bioinorganic chemistry.

Upper troposphere dust belt formation processes vary seasonally and spatially in the Northern Hemisphere

Dust aerosols impact global energy balance substantially by acting as efficient ice nuclei to alter cold cloud properties. However, the estimate of dust indirect effect remains uncertain due to simulating dust distributions poorly and lacking reliable dust observations, especially in the upper-troposphere. Here, we characterize and understand upper-troposphere dust sources and transport with an improved dust dataset derived from A-train satellite lidar and radar measurements and an air parcel trajectory model. The distinct upper-troposphere dust belt over the northern hemisphere has seasonally varying base and top heights of 3.65 ± 2.84 and 8.35 ± 1.50 km above mean sea level and its column loading is strongest during spring (March-April-May). The out-of-phase annual cycles of mid-level dust concentration and westerly wind over source regions control the seasonal upper-tropospheric dust loading variations. African deserts contribute the most (46.3%) to the upper-troposphere dust belt in spring and the synoptic trough is the leading (49%) dust lifting mechanism.

Stability optimization for a simultaneously twisted and compressed rod

PurposeThe authors search the optimal distribution of bending flexure along the axis of the rod. For the solution of the actual problem, the stability equations take into account all possible convex, simply connected shapes of the cross-section. The authors study the cross-sections with equal principal moments of inertia. The cross-sections are similar geometric figures related by a homothetic transformation with respect to a homothetic center on the axis of the rod and vary along its axis. The cross-section that delivers the maximum or the minimum for the critical eigenvalue must be determined among all convex, simply connected domains. The optimal form of the cross-section is known to be an equilateral triangle. The distribution of material along the length of a twisted and compressed rod is optimized so that the rod must support the maximal moment without spatial buckling, presuming its volume remains constant among all admissible rods. The static Euler's approach is applicable for simply supported rod (hinged), twisted by the conservative moment and axial compressing force.Design/methodology/approachThe optimization problems for stability of twisted and compressed rods are studied in this manuscript. The complement for Euler's buckling problem is Greenhill's problem, which studies the forming of a loop in an elastic bar under simultaneous torsion and compression (Greenhill, 1883).FindingsFor determining the optimal solution, the authors directly compare the twisted rods with the different lengths and cross-sections using the invariant factors. The solution of optimization problem for simultaneously twisted and compressed rod is stated in closed form.Research limitations/implications(1) The linear stability equations are applied. (2) No nonlinear or postbuckling effects were accounted. (3) The moment-free, ideal boundary conditions on both ends of the rod assumed.Practical implicationsOne of the most common design cases in mechanical engineering is the concurrent compression and twisting of the straight members. The closed-form solution allows the immediate estimation of the optimization effect for axes and rotors in industrial and automotive engineering.Social implicationsThe application of lighter and material-saving structural elements allow the saving fabrication resources, reducing the mass of vehicles and industry machines. The systematic usage of material optimized structural elements assists the stabilization of global energy balance of Earth.Originality/valueAlbeit the governing ordinary differential equations are linear, the application of the optimality conditions leads to the nonlinearity of the final optimization equations. The search of closed form solution of the nonlinear differential equations is one of the mathematically hardest tasks in engineering mathematics. The closed-form solution presents in terms of higher transcendental functions.

Annual thermal evaluation of a ventilated roof under warm weather conditions of Mexico

An annual thermal evaluation of a ventilated roof (VR) for energy-saving purposes in two Mexican cities with warm weather is presented. It was developed a numerical code based on the global energy balance method to predict the thermal behavior of the VR. The code was verified, and it showed a good agreement with data reported in the literature. Weather data of the coldest and warmest days of each month for the two cities were provided to the numerical code as boundary conditions to perform the simulations. Thus, to quantify the benefits of using the VR, it was compared with a conventional roof (CR). The results showed that the implementation of VR significantly reduces the annual total heat gain by up to 50 and 60% for the climates BWh and Aw, respectively. In addition, it was found that for both climates the payback period of VR is smaller than a year and a half. In this way, VR is a passive technology with high potential to reduce the energy consumption for thermal comfort in buildings at a relatively low cost.

Modern trends in the development of nuclear power: from environmental friendliness to safe utilitarianism

The article discusses the issues of sustainable development of the energy sector of the world economy in accordance with the Sustainable Development Goals: from the active dissemination of clean and environmentally friendly, so-called "green" technologies and technological processes to a significant increase in the share of energy produced from renewable energy sources (RES) by 2030 in the global energy balance and green economy concepts determines the choice of safe types of energy, which, along with renewable energy sources, include nuclear power in accordance with the principle of no significant harm. The Russian Federation ranks fourth in terms of the amount of electricity produced in the world and second, after France, among European countries in terms of nuclear generation capacity. The main trends in the development of the Russian nuclear power industry are presented. It was revealed that the nuclear power industry of the Russian Federation, producing up to 20% of the total energy, ensures compliance with the environmental safety of territories and the safe utilitarianism of radiation technologies in the civilian sector of nuclear energy (nuclear medicine, decontamination of pollution, wastewater treatment, non-destructive testing, radiation materials science, food processing products by ionizing radiation in specialized radiation centers, etc.).

Convective drying of yacón (Smallanthus sonchifolius) slices: A simple physical model including shrinkage

Yacón is a tuberous root from the Andean region, and a functional food due to the presence of fructo-oligosaccharides (FOS). Due to its high moisture in natura, the product is prone to microbial degradation. The evolution of yacón cylindrical slices under convective drying is here studied from experimental work and theoretical considerations about bulk properties. The operation of a pilot-scale convective dryer allowed monitoring the moisture and dimensions of yacón slices. Evolution of moisture under controlled temperature and relative humidity conditions is described through a two-parameter drying kinetics model. A novel approach for estimating shrinkage effects is proposed, comparing measured dimensions with predictions based upon hypothetical shrinkage behaviors. The drying kinetics and the shrinkage approach are finally combined with the global energy balance for a single slice, in order to describe the evolution of surface temperature and other yacón slice properties along the drying period.

Parsing the Kinetic Energy Budget of the Ocean Surface Mixed Layer.

The total rate of work done on the ocean by the wind is of considerable interest for understanding global energy balances, as the energy from the wind drives ocean currents, grows surface waves, and forces vertical mixing. A large but unknown fraction of this atmospheric energy is dissipated by turbulence in the upper ocean. The focus of this work is twofold. First, we describe a framework for evaluating the vertically integrated turbulent kinetic energy (TKE) equation using measurable quantities from a surface mooring, showing the connection to the atmospheric, mean oceanic, and wave energy. Second, we use this framework to evaluate turbulent energetics in the mixed layer using 10 months of mooring data. This evaluation is made possible by recent advances in estimating TKE dissipation rates from long‐enduring moorings. We find that surface fluxes are balanced by TKE dissipation rates in the mixed layer to within a factor of two.

Scale effect in composite materials: Study of the intralaminar damage by means of a micromechanical model

The scale effect in Composite Materials is known as the delay in the appearance of damage in the weakest laminas of a laminate (typically 90 degrees laminas). The availability of ultra-thin plies, of up to 20 microns of thickness, has attracted the attention on this effect, as the use of these plies can imply the delay of the onset of damage at a laminate in a significant manner. The frame of the present work is a micromechanical study of the different phases of damage assumed to lead to the failure of the weakest lamina. Thus, it is assumed that the damage starts by isolated debondings between fibres and matrix, then continuing by the abandon of the interphase, the debonding crack kinking into the matrix, and finally the damage progressing either through the matrix itself or along the interfaces between fibres and matrix, to generate a transversal crack in the 90 degrees lamina. The study is carried out using a multi-scale model based on the Boundary Element Method, with control cells in which the damage at micromechanical level previously described is allowed. Concepts derived from Fracture Mechanics and Interfacial Fracture Mechanics are applied in the analysis. The conclusions obtained with this study are compared with those that clearly manifest the scale effect based on a global energy balance from the pristine state to the final situation with the 90 degrees lamina having a complete transverse crack.

Перспективы развития российского нефтесервиса в условиях перехода к «зеленой энергетике»

The article discusses the basic concepts and principles of clean (green) energy and the reasons for the transition of the global industrial industry to renewable energy sources. Decarbonization trend in the world economy is said to complicate the prospects of the Russian oilfield services, and the task is to determine the possibilities for its sustainable development. To achieve this goal, the current level and the prospects of green energy were analyzed, the problems associated with the transition to renewable energy sources were examined, various ways of the oil and gas business development have been identified. It is established that the current renewable energy sources contribution to the global energy balance is 5 %. However, the policy of economic stimulation for industry decarbonization, which is observed by the industrially developed countries, ensures doubling of the established renewable capacity every four years. The key problems arising from the transition to the renewable energy are revealed, with the main being storage, non-stop energy supply, and the high price of generation products. The paper focuses on the Russian energy industry features which are characterized with the extensive supply of the traditional cheap natural sources, including gas, oil, coal, hydro resources, nuclear power. The transition time to renewable energy is found to be at least 50 years when hydrocarbons remain to be the main source of energy generation. The prospects of sustainable development of the Russian oilfield services are as follows: integration of high technology and new innovation methods of searching, exploration, development, and exploitation of the hydro carbonated deposits; substitution of imported technologies and equipment with the domestic ones; government support of the industry and diversification towards decarbonization energy.

Toward an Improved Global Longwave Downward Radiation Product by Fusing Satellite and Reanalysis Data

Surface longwave downward radiation (LWDR) plays an important role in modulating greenhouse effect and climate change. Constructing a global longtime series LWDR dataset is greatly necessary to systematically and in-depth study the LWDR effect on the climate. However, the current multi-source LWDR products (satellite and reanalysis) show large differences in terms of both spatio-temporal resolutions and accuracy in various regions. Therefore, it is necessary to fuse multi-source datasets to generate more accurate LWDR with high spatio-temporal resolution on a global scale. To this end, a downscaling strategy is firstly proposed to generate LWDR dataset with 0.25° resolution from CERES-SYN data with 1° scale, by incorporating the Land Surface Temperature (LST), Total Column Water Vapor (TCWV) and Elevation. Then a machine learning-based fusion method is provided to generate a global hourly LWDR dataset with spatial resolution of 0.25° by combing three products (CERES-SYN, ERA5 and GLDAS). Compared with ground measurements, the performance of generated LWDR product reveals that the correlation coefficient (R), mean bias error (BIAS), and root mean square error (RMSE) were 0.97, -0.95 W/m2 and 22.38 W/m2 respectively over the land, and 0.99, -0.88 W/m2 and 10.96 W/m2 over the ocean. Specially, it shows improved accuracy in the low and middle latitude regions compared with other LWDR products. Considering its better accuracy and higher spatio-temporal resolution, the new LWDR product can provide essential data for deeply understanding the global energy balance and even the global warming. Moreover, the proposed fusion strategy can be enlightening for readers in the fields of multi-source data combination and big data analysis.

On a global climate model with non-monotone multivalued coalbedo

<p style='text-indent:20px;'>We are concerned with a global energy balance climate model formulated through a parabolic equation whose space domain is a manifold which simulates the Earth surface. The climate energy balance model includes the effect of coalbedo as one of the mean temperature feedback. We extend some mathematical results proved for maximal monotone coalbedo to the case where the coalbedo has not a monotone dependency on temperature. Numerical approximation is performed by the Finite Volume Method which allows to obtain and compare numerical solutions with different values of the coalbedo.</p>

Mizhnarodno-pravove rehuliuvannia spivpratsi derzhav u haluzi vidnovliuvanoi enerhetyky

The current state of international legal regulation of relations of renewable energy is considered, the need to analyse the dynamics of the formation of rules of conduct of states, which are enshrined in various sources, including those enshrined in Art. 38 of the Charter of the International Court of Justice, as well as a significant array of rules, which international law has been called «soft law». It is shown that in the domestic doctrine of international law is quite a common to view that the main sources of so-called «soft law» are resolved of intergovernmental organizations of the UN system and its offices, especially the UN General Assembly, political acts of regional conferences, and organizations, others international acts adopted by states, intergovernmental organizations, which are not legal but moral and political in nature. The process of formation of the international regulatory framework in the field of renewable energy is analysed, which shows that the development of international policy and «soft law» in this area has gone through four conditional stages: the formation of general principles of cooperation; introduction of the concept of sustainable development in the international legal environment; recognition of energy as a component of sustainable development; launch of the UN Sustainable Energy for All initiative. It is noted that despite all efforts, the share of new and renewable energy sources in the global energy balance remains extremely low. Referring to this fact, the General Assembly calls for measures to be taken to ensure the cost-effective use of such types of energy. It is noted that in the array of norms of international law, which directly or indirectly relate to the field of renewable energy, the vast majority is a set of rules of «soft law». It is shown that the world powers seek to cooperate through the work of specialized international organizations that are designed to introduce the production of renewable energy sources. The focus is on the International Renewable Energy Agency (IRENA), the establishment of which is, of course, a necessary way to implement renewable energy. Because the recommendatory nature of these international organizations does not contribute to the positive purpose of such cooperation. In order to unify the international legal regulation of renewable energy, it is necessary to develop a common international legal framework in this area with mandatory compliance with the legal norms of all participants.

Energy Resources Exploitation in the Russian Arctic: Challenges and Prospects for the Sustainable Development of the Ecosystem

According to the forecasts made by IEA, BP, and Total in early 2021, the demand for hydrocarbons will continue for decades, and their share in the global energy balance will remain significant. Russia, as a key player in the energy market, is interested in maintaining and increasing hydrocarbon production, so further exploitation of the Arctic energy resources is an urgent issue. A large number of onshore oil and gas projects have been successfully implemented in the Arctic since the 1930s, while recently, special attention has been paid to the offshore energy resources and implementation of natural gas liquefaction projects. However, the implementation of oil and gas projects in the Arctic is characterized by a negative impact on the environment, which leads to a violation of the ecological balance in the Arctic, and affects the stability of its ecosystem, which is one of the most vulnerable ecosystems on the planet. The main goal of the present study is to understand how the implementation of oil and gas projects in the Arctic affects the ecosystem, to assess the significance of this process, and to find out what the state and business could do to minimize it. In the article, the authors analyze energy trends, provide brief information about important oil and gas projects being implemented in the Arctic region of Russia, and investigate the challenges of the oil and gas projects’ development and its negative impacts on the Arctic environment. The main contributions of this paper are the identification of all possible environmental risks and processes accompanying oil and gas production, and its qualitative analysis and recommendations for the state and business to reduce the negative impact of oil and gas projects on the Arctic ecosystem. The research methodology includes desk studies, risk management tools (such as risk analysis, registers, and maps), brainstorming, the expert method, systematization, comparative analysis, generalization, and grouping.

Estimation of the effects of water mist system on the tunnel critical velocity due to smoke cooling

A water mist system can reduce the tunnel critical velocity since it cools the smoke and reduces the buoyancy force. To study this, a theoretical model was derived using the theory of the critical Froude number and a global energy balance concept. The evaporation rate of the mists was found to be the dominating factor affecting the ratio between the critical velocities with and without the suppression. To test this, the CFD code FDS 6.7.3 was used to model a 60 m long tunnel with a water mist operating downstream to cool the smoke. Nine fire sizes in the range of 10 483 kW to 42 988 kW were modelled. With water mist operation, the theoretical model can accurately predict the reduction in critical velocity for small fire sizes. By the addition of a calibration factor to account for the change in the critical Froude number, the developed model can also provide reliable predictions for large fires whose critical velocities are independent of the heat release rate. The findings prove that the critical Froude number theory can be applied even in the presence of a water mist system and reveal a fact that only when the mist cools the rising hot plume and backlayering flow can the critical velocity be reduced.

Numerical study on the dissipation mechanisms in sloshing flows induced by violent and high-frequency accelerations. I. Theoretical formulation and numerical investigation

A numerical study of damping effects on aircraft wings caused by liquid sloshing inside the fuel tanks has been performed. To model this phenomenon, a tank-fluid system is vertically excited with a periodic law of motion. The work has two parts. In the present Part I, a mathematical formalism of the global energy balance in different frames of reference is provided. Then, an enhanced Smoothed Particle Hydrodynamics model, (delta-LES-SPH), has been applied for the simulation of this violent flow. Multiple energy dissipation mechanisms such as liquid impacts and turbulence are discussed. Comparison with experimental results and the fluid-structure interaction case is carried out in Part II.