Energy Balance Climate Model

I use the seasonal simulation to explore the sensitivity of this energy balance climate model to such features of the climate system as permanent ice and snow at high latitudes, seasonal ice and snow, cloud cover, carbon dioxide amount, and the distribution of the continents. 

The climate is an important aspect of the environment, an aspect that interacts strongly with the composition of the ocean and atmosphere. This interaction works in two ways Climate is influenced by composition through the greenhouse effect, and climate also influences composition through its effect on reaction rates, particularly on weathering and the flux of dissolved constituents into the sea. Full-scale climate models are exceedingly complicated and can run only on supercomputers. But here I shall demonstrate how one aspect of the climate system—average tern- 

The simulation balances the radiant energy absorbed by a portion of the Earth s surface and the overlying atmosphere, the energy lost to space from this portion of the Earth, and the transport of energy from one portion of the Earth to another by the ocean and atmosphere. It solves for a single parameter of climate, surface temperature. 

The transport of heat between latitude bands is assumed to be diffusive and is proportional to the temperature difference divided by the distance between the midpoints of each latitude band. This is the temperature gradient. In this simulation all these distances are equal, so the distance need not appear explicitly. The temperature gradient is multiplied by a transport coefficient here called diffc, the effective diffusion coefficient. The product of the diffusion coefficient and the temperature gradient gives the energy flux between latitude zones. To find the total energy transport, we must multiply by the length of the boundary between the latitude zones. In 

DIM y(nrow), dely(nrow), yp(nrow), incind(nrow) 

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Significant economies of computation are possible in systems that consist of a one-dimensional chain of identical reservoirs. Chapter 7 describes such a system in which there is just one dependent variable. An illustrative example is the climate system and the calculation of zonally averaged temperature as a function of latitude in an energy balance climate model. In such a model, the surface temperature depends on the balance among solar radiation absorbed, planetary radiation emitted to space, and the transport of energy between latitudes. I present routines that calculate the absorption and reflection of incident solar radiation and the emission of long-wave planetary radiation. I show how much of the computational work can be avoided in a system like this because each reservoir is coupled only to its adjacent reservoirs. I use the simulation to explore the sensitivity of seasonally varying temperatures to such aspects of the climate system as snow and ice cover, cloud cover, amount of carbon dioxide in the atmosphere, and land distribution. 

Program DAV08 is an 18 reservoir energy balance climate model... 

I also applied the revised computational method to calculate zonally averaged temperature as a function of latitude. I introduced an energy balance climate model, which calculates surface temperature for absorbed solar energy, emitted planetary radiation, and the transport of heat between... 

Chapter 8 presented the last of the computational approaches that I find widely useful in the numerical simulation of environmental properties. The routines of Chapter 8 can be applied to systems of several interacting species in a one-dimensional chain of identical reservoirs, whereas the routines of Chapter 7 are a somewhat more efficient approach to that chain of identical reservoirs that can be used when there is only one species to be considered. Chapter 7 also presented subroutines applicable to a generally useful but simple climate model, an energy balance climate model with seasonal change in temperature. Chapter 6 described the peculiar features of equations for changes in isotope ratios that arise because isotope ratios are ratios and not conserved quantities. Calculations of isotope ratios can be based directly on calculations of concentration, with essentially the same sources and sinks, provided that extra terms are included in the equations for rates of change of isotope ratios. These extra terms were derived in Chapter 6. 

Thompson, S. L., and S. H. Schneider. 1979. A seasonal zonal energy balance climate model with an interactive lower layer. J. Geophys. Res. 84, 2401-14. 

Calculations of annual average global SAT using the energy-balance climate model with various scenarios of temporal variations of C02 concentrations have led to SAT intervals in 2020, 2050, and 2100 to be 0.3°C-0.9°C, 0.7°C-2.6°C, and 1.4°C-5.8°C, respectively. Due to the thermal inertia of the ocean, delayed warming should manifest itself within 0.1°C-0.2°C/10 years (such a delay can take place over several decades). 

Harvey, L. D. D. (1988). A semianalytic energy balance climate model with explicit. sea ice and snow physics. / Climate I, 1065- 1085. 

Crowley (2000) estimated the contributions of various factors to climate formation (SAT changes) for the last 1,000 years using an energy-balance model of climate. According to the results obtained... 

Instead of the GCMs, it has been common to use Energy Balance Models (EBMs) to study changes in climate on orbital timescales. These types of models can be grouped into four categories (1) annual mean atmospheric models (2) seasonal atmospheric models with a mixed layer ocean (3) Northern Hemisphere ice sheet models and (4) coupled climate-ice sheet models, which in some cases include a representation of the deep ocean. 

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