Water budget model

Figure 9.13 Scheme of the SM2-U energy and water budget models (a) with 7 surface types (pav, bare, nat, roof, vega, vegn, wat) and 3 soil layers, (b) Energy budget of paved surfaces. 

The CENTURY model also includes a simplified water budget model that calculates monthly evaporation and transpiration water loss, water content of the soil layers, snow water content, and water flows between the soil layers. The main abiotic driver for the water budget model is the potential evapotranspiration rate, which is calculated as a function of the average monthly maximum and minimum air temperature. Near surface soil temperature is calculated as a function of maximum and minimum air temperatures, litter and standing plant biomass. The plant production model calculates potential plant production as a function of soil temperature and the ratio of actual water loss to potential water loss. Potential plant production is reduced when nutrients limit growth and the element that is most limiting for plant growth controls plant production. The nutrient... 

The weight of soil carried in the surface runoff has been estimated by relating the sediment load to the rate of energy dissipation at the land surface by the rainfall and flowing water. The resistance of the soil to eroding forces has also been considered (4), and a method has been developed to estimate the net effect of erosion on radioaerosol transport. The volume of the liquid phase is estimated on a continuous basis by the Stanford watershed model, through consideration of a water budget. This feature has been retained in the HTM-1. 

Twilley, R.R., and Chen, R. (1998) A water budget and hydrology model of a basin mangrove forest in Rookery Bay, Florida. Mar. Freshwat. Res. 49, 309-323. 

Probst et al. (2000) measured strontium isotopes and major element concentrations of the various hydrochemical reservoirs in the Streng-bach Catchment, France. Based on chemical budgets and a rock-water interaction model used to estimate the weathering end-member composition, they concluded that —50% of the dissolved strontium in stream water was atmospherically derived. Aubert et al. (2002b)... 

Dupont, S., Mestayer, P.G., Guilloteau, E., Berthier, E., and Andrieu, H. (2005) Parameterisation of the Urban Water Budget with the Sub-Meso Soil Model , J. Appl. Meteorol., submitted. 

Fisheries also have some influence on overall contaminant budgets of the Baltic Sea (MacKenzie et al., 2004). Fishing in the early 1980s removed 40-60 kg PCB/year from the Baltic and ca. 10 kg/year in the mid 1990s (most recent data available). These removals are comparable to some components (i.e., degradation in water column, advective loss to North Sea) of an existing PCB budget model for the Baltic Sea (Wania et al., 2001 MacKenzie et al., 2004). 

FIGURE 12 Seasonal variation of the components of the monthly mean surface water budget (cm/day) averaged over the continental region of 45-60° latitude for (a) a quadrupling of CO2, (b) the control experiment, and (c) the difference between the two experiments. Here, both evaporation and runoff are plotted in the negative (-) because they represent losses of water from the model surface. Shaded regions in both (a) and (b) denote the portion of total precipitation (dotted lines) attributable to snowfall. [From Wetherald, R. T, and Manabe, S. (1995). J. Clim. 8,3096-3108.]... 

Ramier, D., E. Berthier, P. Dangla, and H. Andrieu. 2006. Study of the water budget of streets Experimentation and modelling. Water Sci. Technol. 54(6-7) 41 8. 

An important consequence of such a model is that the effect of such sedimentary systems on the ocean Mo isotope budget is not represented by a, but rather by the relative fluxes of the isotopes across the sediment-water interface. This effective fractionation factor, is likely to be smaller than a (Bender 1990 Braudes and Devol 1997) because the diffusive zone acts as a barrier to isotope exchange with overlying waters, approximating a closed system. 

Prognostic models reproduce the process of evolution of the initial condition of the current, temperature, and salinity (density) fields under the action of the boundary conditions (momentum, heat, moisture, and mass fluxes) without any correction for the observational data. Usually, the climatic annual cycle of the variabilities in the circulation and thermohaline water structure is modeled. The calculations are performed until the parameters of this cycle stabilize, i.e. the differences between two successive become lower than a certain specified value. Then, the results obtained (model current, temperature, and salinity fields energy, dynamic, and thermodynamic budgets, etc.) un-... 

The theoretical models considering the influence of (algal) viruses on the carbon cycle that exist to date are steady-state models assuming a fixed percentage of the algal population dying due to viral lysis. A bloom of Phaeocystis in, for example, temperate eutrophic coastal waters is, however, clearly not a steady-state situation. Based on the ecosystem model by Ruardij et al. (2005), we established a carbon budget for the main players... 

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