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A Concept of Environmental Forecasting and Variational Organization of Modeling Technology. Vladimir Penenko Institute of Computational Mathematics and Mathematical Geophysics SD RAS. Challenges of environment forecasting :. Predictability of climate-environment system?

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Presentation Transcript

A Concept

of Environmental Forecasting

and Variational Organization

of Modeling Technology

Vladimir Penenko

Institute of Computational Mathematics and Mathematical Geophysics SD RAS


Challenges of environment forecasting:

  • Predictability of climate-environment system?

  • Stability of climatic system?

  • sensitivity to perturbations of forcing

  • Features of environment forecasting: uncertainty

  • in the long-term behavior of the climatic system;

  • in the character of influence of man-made factors

  • in the conditions of changing climate


Uncertainty

  • Discrepancy between models and real phenomena

  • insufficient accuracy of numerical schemes and algorithms

  • lack and errors of input data


A concept of environmental forecasting
A CONCEPT OF ENVIRONMENTAL FORECASTING

  • Basic idea:

    we use inverse modeling technique

    to assess risk and vulnerability of territory

    (object) with respect to harmful impact

    in addition to traditional forecasting the state functions variability by forward methods


Theoretical background

  • The methodologyis based on:

  • control theory,

  • sensitivity theory,

  • risk and vulnerability theory,

    • variational principles in weak-constrained formulation,

    • combined use of models and observed data,

    • forward and inverse modeling procedures,

    • methodology for description of links between regional and global processes ( including climatic changes) by means of orthogonal decomposition of functional spaces for analysis of data bases and phase spaces of dynamical systems


Basic elements for concept implementation:

  • models of processes

  • data and models of measurements

  • global and local adjoint problems

  • constraints on parameters and state functions

  • functionals: objective, quality, control, restrictions etc.

  • sensitivity relations for target functionals and constraints

  • feedback equations for inverse problems





Transport and transformation model

of gas pollutants and aerosols

Operators of transformation


Variational form of model’s set:

hydrodynamics+ chemistry+ hydrological cycle


Variational form of convection diffusion operators
Variational form of convection-diffusion operators

boundary conditions on


Model of observations

Variational form


Functionals for generalized description

of information links in the system


Variational principle

Augmented functional for computational technology

Algorithms for construction of numerical schemes


The universal algorithm

of forward & inverse modeling


Some elements

of optimal forecasting and design

The main sensitivity relations

Algorithm for calculation

of sensitivity functions


Algorithms for uncertainty calculation

based on sensitivity analysis and

data assimilation:

in models of processes

in initial state

in model parameters and sources

in models of observations


Fundamental role of uncertainty functions

  • integration of all technology components

  • bringing control into the system

  • regularization of inverse methods

  • targeting of adaptive monitoring

  • cost effective data assimilation


Optimal forecasting and design

  • Optimality is meant in the sense that estimations of the goal functionals do not depend on the variations :

  • of the sought functions in the phase spaces of the dynamics of the physical system under study

  • of the solutions of corresponding adjoint problems that generated by variational principles

  • of the uncertainty functions of different kinds which explicitly included into the extended functionals


Construction of numerical approximations
Construction of numerical approximations

  • variational principle

  • integral identity

  • splitting and decomposition methods

  • finite volumes method

  • local adjoint problems

  • analytical solutions

  • integrating factors


4DVar real time data assimilation algorithm

Basic elements in frames of splitting and decomposition schemes:

p - number of stages

- operator of the model,


Scenario approach for environmental purposes

  • Inclusion of climatic data via decomposition of phase spaces on set of orthogonal subspaces ranged with respect to scales of perturbations

  • Construction of deterministic and deterministic-stochastic scenarios on the basis of orthogonal subspaces

  • Models with leading phase spaces




Leading orthogonal subspaces
Leading orthogonal subspaces years

36 years, 26.66%

46 years, 26.63%

56 years,26.34%


Risk vulnerability assessment some scenarios for receptors in siberia

Risk/vulnerability assessment yearsSome scenarios for receptorsin Siberia


Ekaterinburg years

Yakutsk

Khanti-Mansiisk

Krasnoyarsk

Tomsk

Mondy

Ulan-Ude

Tory

Ussuriisk

“climatic”

April


Long term forecasting for lake baikal region risk function
Long-term forecasting for Lake Baikal region yearsRisk function

Surface layer, climatic October


Conclusion years

  • Algorithms for optimal environmental

  • forecasting and design are proposed

  • The fundamental role of uncertainty is highlighted



Eigenvalues of gram matrix as a measure of informativeness of orthogonal subspaces
Eigenvalues of Gram matrix as yearsa measure of informativeness of orthogonal subspaces

Separation of scales : climate/weather noise

36 years

46 years

56 years



Volcano Schiveluch ( Kamchatka, Russia) eruption years19-21.05.2001. Forward problem. Surface layer aerosol concentrations ( <2 mkm)


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