Surface-atmosphere energy exchange

Summer days in the boreal zone are long, the daily period of illumination increasing virtually to 24 h in the north. Radiation is a primary driving variable of earth surface-atmosphere energy exchange including evaporation. On a clear day, for an unpolluted atmosphere, shortwave irradiance at the earth s surface obtains a maximum of around 70-80% of the extraterrestrial value due to... 

Dan et al. (2005) developed the AVIM model which combines the physical and biological components of the gas and energy exchange between the atmosphere and vegetation cover. The model has a spatial resolution of 1.5° x 1.5° over the surface and selects in the atmosphere pixels 7.5° by longitude and 4.5° by latitude. The model gives stable results and can be used as a GMNSS unit. 

The processes of transport at the atmosphere-water surface border have been well studied. The transport of moisture from the surface of a water body into the atmosphere is one of the complicated physical processes of mass and energy exchange across the water-air interface (Figure 4.12). These processes are functions of many climatic parameters and, to a large extent, are regulated by eddy motions in the surface layer of the atmosphere determined by the wind field. 

The temperature of seawater is fixed at the sea surface by heat exchange with the atmosphere. The average incoming energy from the Sun at the Earth s surface is about four times higher at the equator than at the poles. The average infrared radiation heat loss... 

The value of E in relation to like the value of gj, indicates the evaporative nature of the surface so E < E q or E/Ee, < 1 reflects surface dryness or stomatal closure as well as the balance of energy exchange between the atmosphere and the underlying surface. By definition, E > Ef, can be caused only by advection. As implied above with respect to the partitioning of temperature, this may also result from the entrainment of dry air from above the convective boundary layer that develops daily over the earth surface. To further illustrate the relation between E and Ef, in terms of surface characteristics, it is helpful to write the Penman-Monteith equation (Monteith and Unsworth, 1990),... 

It is obvious, then, that we must couple two models of atmosphere and ocean for prediction of seasonal time scale. Physically, these two models interact with each other in sucha way thatthe atmospheric model, uses SST predicted by the ocean model, which requires the surface wind stress, the net surface energy flux (i.e., the sum of sensible and latent heat fluxes), and the net influx of fresh water (i.e., precipitation minus evaporation). The atmospheric model requires information on surface energy exchange as well as the SST. 

This study presents kinetic data obtained with a microreactor set-up both at atmospheric pressure and at high pressures up to 50 bar as a function of temperature and of the partial pressures from which power-law expressions and apparent activation energies are derived. An additional microreactor set-up equipped with a calibrated mass spectrometer was used for the isotopic exchange reaction (DER) N2 + N2 = 2 N2 and the transient kinetic experiments. The transient experiments comprised the temperature-programmed desorption (TPD) of N2 and H2. Furthermore, the interaction of N2 with Ru surfaces was monitored by means of temperature-programmed adsorption (TPA) using a dilute mixture of N2 in He. The kinetic data set is intended to serve as basis for a detailed microkinetic analysis of NH3 synthesis kinetics [10] following the concepts by Dumesic et al. [11]. 

One of our recently-developed systems is a good example of adapting laboratory methods to ln-sltu field measurements. We developed this system to measure the exchange of CO2 between the atmosphere and the surface of the earth. The transfer of matter and energy from a... 

Radiocarbon. Radiocarbon (14C) is unstable, with a half-life of 5730yr, and decays by emission of an electron to form 14N. It is continuously produced in the upper atmosphere by interactions of high-energy cosmic rays with the upper atmosphere. The 14C is oxidized to 14C02 within a few weeks and is then mixed into the troposphere (the lower, well-mixed part of the atmosphere), where it is taken up by plants during photosynthesis and exchanges with the surface waters of the ocean. 

The complex of feedbacks controls interactive exchange with energy, water, and carbon between the atmosphere and the Earth s surface causing a response of these fluxes to disturbances such as transformation of land cover or pollution of the World Ocean with oil. Substantial feedbacks are physiological responses of vegetation communities to changes in temperature and humidity of the atmosphere and soil. 

Fritschen, Leo J. and Robert Edmonds. in "Atmosphere-surface exchange of particulate and gaseous pollutants" ERDA Symposium Series 38 Technical Information Center, Energy Research and Development Administration, 1976 p. 988. 

Lichens are adapted to accumulate all the elements necessary for their life from the atmosphere. They have no root system and absorb very little from the substrate on which they grow. Atmospheric materials, including trace metals and radionuclides, can be concentrated by particulate entrapment, ion exchange, electrolytic sorption and processes mediated by metabolic energy (Crete et al., 1992). Passive particulate trapping is, however, thought to be the dominant uptake mechanism. This is also true for mosses which absorb nutrients directly through leaf and stem surfaces. 

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