Weather and Climate Manipulation as an Optimal Control for Adaptive Dynamical Systems

Известия Российской академии наук. Физика атмосферы и океана

Yusupov

2019

The present climate is characterized not only by the trend due to the increase in the concentrations of greenhouse gases in the atmosphere, but also by fluctuations covering a wide range of frequencies and scales. The global climate variability, calculated via the computational results from the Coupled Model Intercomparison Project Phase 5 of the World Climate Research Program, show significant inter-model differences. In particular, inter-model distinctions in decadal anomalies of the global and hemispheric temperatures reach four times the value. However, unlike the inter-model differences in climate sensitivity, the reasons for a wide range of estimates of climate variability are still unclear. Based on the two-component energy-balance stochastic model, the paper analyzes the inter-annual and inter-decadal variability of the mean global surface temperature (GST) to feedback and the thermal inertia of the atmosphere-ocean system, assuming that the external forcing is random fluctu-ations of the radiation balance at the top of the atmosphere. Using the obtained ab-solute and relative sensitivity functions, the influence of thermal inertia and feed-backs in the climate system on the inter-annual and inter-decimal variability (variance) of the GST and its spectrum is estimated.

Section: T T Dt G T a G T T B Tunclassified

unclassified

Estimating the influence of thermal inertia and feedbacks in the atmosphere–ocean system on the variability of global surface temperature

Известия Российской академии наук. Физика атмосферы и океана

Yusupov

2019

“…Weather modification and geoengineering represent the deliberate alteration of atmospheric and climate conditions, locally or globally, by humans using the available assets and resources based on the existing theoretical understanding of weather and climate processes (see [1][2][3][4][5][6] and references herein). Over the years, people have sought to modify the environment, including the atmosphere, in an attempt to adapt to its ever-changing conditions.…”

Section: Introductionmentioning

confidence: 99%

An Optimal Control Perspective on Weather and Climate Modification

Yusupov

2021

Mathematics

Self Cite

Intentionally altering natural atmospheric processes using various techniques and technologies for changing weather patterns is one of the appropriate human responses to climate change and can be considered a rather drastic adaptation measure. A fundamental understanding of the human ability to modify weather conditions requires collaborative research in various scientific fields, including, but not limited to, atmospheric sciences and different branches of mathematics. This article being theoretical and methodological in nature, generalizes and, to some extent, summarizes our previous and current research in the field of climate and weather modification and control. By analyzing the deliberate change in weather and climate from an optimal control and dynamical systems perspective, we get the ability to consider the modification of natural atmospheric processes as a dynamic optimization problem with an emphasis on the optimal control problem. Within this conceptual and unified theoretical framework for developing and synthesizing an optimal control for natural weather phenomena, the atmospheric process in question represents a closed-loop dynamical system described by an appropriate mathematical model or, in other words, by a set of differential equations. In this context, the human control actions can be described by variations of the model parameters selected on the basis of sensitivity analysis as control variables. Application of the proposed approach to the problem of weather and climate modification is illustrated using a low-order conceptual model of the Earth’s climate system. For the sake of convenient interpretation, we provide some weather and climate basics, as well as we give a brief glance at control theory and sensitivity analysis of dynamical systems.

“…Meanwhile, exploring Earth's global climate as controlled dynamical system, we can approach geoengineering from the perspective of optimal control theory [46][47][48][49]. Within the optimal control framework, the goal of geoengineering can be formulated in terms of extremal problem, which involves finding control functions and the corresponding climate system trajectory that minimize or maximize a certain objective functional (also referred to as performance measure or index) subject to various constraints (e.g., References [50,51]. If x is the state vector of climate system and u is the vector of control variables, then the abstract extremal problem can be formulated as follows:…”

Section: Introductionmentioning

confidence: 99%

Estimating the Impact of Artificially Injected Stratospheric Aerosols on the Global Mean Surface Temperature in the 21th Century

2018

Climate

Self Cite

In this paper, we apply the optimal control theory to obtain the analytic solutions of the two-component globally averaged energy balance model in order to estimate the influence of solar radiation management (SRM) operations on the global mean surface temperature in the 21st century. It is assumed that SRM is executed via injection of sulfur aerosols into the stratosphere to limit the global temperature increase in the year 2100 by 1.5 °C and keeping global temperature over the specified period (2020–2100) within 2 °C as required by the Paris climate agreement. The radiative forcing produced by the rise in the atmospheric concentrations of greenhouse gases is defined by the Representative Concentration Pathways and the 1pctCO2 (1% per year CO2 increase) scenario. The goal of SRM is formulated in terms of extremal problem, which entails finding a control function (the albedo of aerosol layer) that minimizes the amount of aerosols injected into the upper atmosphere to satisfy the Paris climate target. For each climate change scenario, the optimal albedo of the aerosol layer and the corresponding global mean surface temperature changes were obtained. In addition, the aerosol emission rates required to create an aerosol cloud with optimal optical properties were calculated.