The paper analyzes some factors affecting the parallel implementation performance of the atmospheric general circulation model designed on a cluster type multiprocessor computer. It considers several modifications of the initial parallel code of this model in order to improve both its computational efficiency and processor load balancing. The numerical scheme is modified according to the time of the atmospheric general circulation model for parallel computing of dynamics and physics blocks. The proposed procedure is used along with the procedures of paralleling the dynamics and physics blocks based on decomposition of the computational domain. It allows both optimizing the processor load balancing and increasing the paralleling efficiency. The data obtained while using the scheme for the physics block load balancing allow for complication of the physics block without increasing the total computational time. The results of numerical experiments are given.
Parkhomenko V. Algorithm for computational performance improvement and processor load balancing to simulate the general atmosphere circulation. Маthematical Modeling and Coтputational Methods, 2016, №3 (11), pp. 93-109
The article considers a model of the climate, including interacting blocks of the ocean, atmosphere and sea ice. The model describes the deep thermohaline circulation of the oceans and the main characteristics of the other elements of the climate system. The paper presents model operating in the mode of the seasonal variations of solar radiation. The changes in atmospheric temperature in XXI century for different scenarios of CO2 concentration variations are calculated.
Parkhomenko V. Global climate model including description of thermohaline circulation of the World Ocean. Маthematical Modeling and Coтputational Methods, 2015, №1 (5), pp. 94-108
The aim of this work is to consider a global model of the carbon cycle. The model describes the production process of forest ecosystems taking into account the seasonal sicle of climatic factors. It is designed to simulate a long period of time as part of a global climate model of intermediate complexity. It has been established that the global characteristics of the climate system reach a steady state over a period of about 2000 years, and the model works steadily. The temporal and spatial distributions of the obtained climatic characteristics and the biogeochemical carbon cycle of terrestrial vegetation are given.
Пархоменко В.П. Глобальная климатическая модель с учетом биогеохимического углеродного цикла растительности суши. Математическое моделирование и численные методы, 2021, № 2, с. 38–53.
This work is devoted to the study and application of methods of intellectual analysis for the implementation of the scheme of the nowcasting of dangerous phenomena. In the course of the work, data sets were formed with differ in the methods of information processing for their preparation. For each set, a number of mathematical models were constructed for classifying cloud cells according to the degree of danger of tornadoes forming from them. The Python programming language has been chosen as the main development language. The work is of great practical importance in the field of forecasting weather events. Its novelty lies in the use of modern machine learning methodology, instead of the traditional approach to data extrapolation, widely used in various schemes of nowcasting.
Шершакова А.О., Пархоменко В.П. Методы интеллектуального анализа данных в модели наукастинга опасных явлений. Математическое моделирование и численные методы, 2021, № 3, с. 88–104.
The paper gives the results of numerical calculations on the description of the Earth's climate with the displacement of its axis of rotation, the possibility of which is proven by some geological, archaeological and historical data. The study assumes that the axis inclination angle to the ecliptic plane is maintained. We carried out some calculations on modeling the process of transition from paleoclimate to the current one as a result of displacement of the Earth's rotation axis into the present position. The calculations are based on the hydrodynamic three-dimensional global climate model. As a result, we introduced an approach to calculating the wind speed in the energy-and-water balance atmospheric model. Finally, we developed a method for forming and using the necessary maps and connections between them at the rotation of the Earth's axis.
Parkhomenko V.P.Modeling the process of transition from paleoclimate to the current one as a result of a strong change in conditions .Маthematical Modeling and Computational Methods, 2017, №3 (15), pp. 105–118
The purpose of the study was to estimate the possibility of climate stabilization at the present level by controlled sulfate aerosols emissions into the stratosphere, which reflect part of the incoming solar radiation, i.e. geoengineering. The study is based on a three-dimensional hydrodynamic model of the global climate, including an ocean model with
a real configuration of depths and continents, as well as a model of sea ice evolution, and a model of general atmospheric circulation. We studied the possibility of obtaining the predetermined spatial and temporal global distribution of the stratospheric aerosol under conditions when there is a limited number of aerosol sources. Wind transport and aerosol deposition were taken into account.
Пархоменко В.П. Моделирование пространственного и временного глобально-го распределения стратосферного аэрозоля искусственного происхождения для стабилизации климата. Математическое моделирование и численные методы, 2018, № 4, с. 107–119.
During the last decades we are witnessing climate changes. Scientists assume global warming to be the result of man-generated increase of green house gases in the atmosphere, the most important one being СО2. The article deals with the problem and describes cutting-edge solutions for stabilising climate. The research makes use of a seasonal global combined threedimensional hydrodynamic model of climate. This model of climate includes model of the World Ocean with real depths and configuration of continents, model of evolution of sea ice and energy — moisture balance model of the atmosphere. The first stage covers estimation of climate change through 2100 following IPCC A2 СО2 increase scenario. The calculations yield rise of average annual surface temperature of the atmosphere by 3,5 С. A number of calculations have been made to estimate possibility of stabilising climate at the level of 2010 by means of controlled release of sulphate aerosol into stratosphere. The aerosol will reflect and disperse a part of the coming solar radiation. We have calculated concentration (albedo) of the aerosol from 2010 to 2100 which will enable us to stabilise the average annual temperature of the surface layer of atmosphere. We have shown that by this way it is impossible to achieve the seasonal uniform approximation to the existing climate, although it is possible to significantly reduce the greenhouse warming effect. Provided that the aerosol is distributed evenly in space in stratosphere, we can stabilize the average annual temperature of the atmosphere, herewith in middle and low latitudes the climate will be colder by 0,1…0,2 С and in high latitudes it will be warmer by 0,2…1,2 С. Besides, these differences are essentially seasonal in nature, they increase in winter. If we stop releasing the aerosol in 2080 the average annual global temperature of the atmosphere will rise, reaching the former value without the aerosol by the year 2100.
Parkhomenko V. Modelling global climate stabilisation by controlled emission of stratospheric aerosol. Маthematical Modeling and Coтputational Methods, 2014, №2 (2), pp. 115-126
A three-dimensional hydrodynamic model of the global climate is presented, including a block of the atmosphere general circulation, a block of the ocean in geostrophic approximation with a frictional term in the horizontal momentum equations with a real distribution of depths and continents, a block of the sea ice evolution. Calculations of possible climate change up to 2100 are given on the basis of several CO2 growth scenarios. A significant decrease in the meridional flow of water in the Atlantic has been established during the implementation of a strong CO2 growth scenario. Numerical experiments have been carried out to identify potential hysteresis associated with attenuation, up to blocking (under certain conditions) Atlantic meridional thermohaline circulation.
Пархоменко В.П. Организация численных экспериментов на совместной глобальной модели атмосферы и океана. Математическое моделирование и численные методы, 2022, № 4, с. 31–4
Studies indicate the mass death on Earth of a significant number of biological groups, in particular - dinosaurs, at the end of the Cretaceous, 66 million years ago. The final cause of this phenomenon remains the subject of discussion. Currently, there are two main theories: large-scale volcanic eruptions and the impact of an asteroid that formed the Chicxulub crater (Mexico). The production of sulfur-containing gases from the evaporation of the surface layers of the Earth during collisions is now considered the main source of climatic effects, since they form stratospheric sulfate aerosols that block sunlight and thus cool the atmosphere of the Earth and prevent photosynthesis. This paper presents the use of a joint climate model to study the effects of this asteroid on the Earth’s climate. It was established that, depending on the time spent in the stratosphere of the aerosol, the global annual average temperature of the surface air decreased by 18 ° C–26 ° C, remained below zero for 4-30 years and a recovery time of more than 30 years was observed.
Пархоменко В.П. Моделирование климатических последствий падения крупного астероида 66 млн лет назад. Математическое моделирование и численные методы, 2019, № 2, с. 68–83.