The Greenhouse Effect is a natural phenomenon that warms up the earth. It works on the same principles as the ordinary garden glasshouse, which allows the light to get in, but does not allow the heat to get out. The earth is surrounded by a shield of atmospheric gases primarily nitrogen (78 %), and oxygen (21%). The remainder of the air composition is made up of what are called as “trace gases,” which include carbon dioxide (CO₂), methane (CH₄) etc. The earth maintains its temperature through insulation with a 'thermal blanket' of greenhouse gases which allow penetration of the sun's rays but prevent some heat radiating back into space. Light from the sun penetrates the atmosphere and reaches the earth surface, warming it up.

Biomass burning is an important source of atmospheric CO₂, aerosols and chemically important gases. It is as important to global chemistry as industrial activities in the developed world [Crutzen and Andreae, 1990]. Biomass burning is a key component of the global carbon budget, currently releasing 2.6 GtC from fires in the tropical and subtropical ecosystems (van der Werf et al. [2003], to be compared to the 5.6 GtC released from fossil fuels) to the atmosphere each year, most of it being emitted in the form of carbon dioxide, although there is important spread amongst various estimates. Biomass burning contributes up to 40% of gross atmospheric CO₂ (IPCC, 2001), 38% of tropospheric O₃, and 10 % of CH₄.

An accurate knowledge of the thermodynamics of the carbonic acid system in seawater is crucial to our understanding of the behavior of carbon dioxide in seawater. In particular, this knowledge is needed whenever a particular property needs to be calculated from measurements of other related properties; e.g., the estimation of the partial pressure of CO2 in air that is in equilibrium with a sample of sea water, p(CO2), from measurements of the total dissolved inorganic carbon, CT, and of the total alkalinity, AT, of a water sample. This calculation is particularly important for ocean models, which transport CT and AT, but which need to calculate p(CO2) at the sea surface so as to represent air-sea exchange processes. Numerous determinations of dissociation constants for carbon dioxide in seawater media have been published over the years. In each case the authors have recommended “best” values for the dissociation constants, and often the constants are represented in these papers by interpolating equations or tables. Furthermore, a number of investigators have attempted to assess the thermodynamic consistency of the various published values for these dissociation constants with analytical measurements made on natural seawater. Despite all this work, the results of these efforts are, as yet, not conclusive. I shall present a review of the situation and will try to provide a clear description of the magnitude of the problems, their possible sources, and their importance to understanding the behavior of CO2 in seawater.

We present preliminary results from hydrogen isotopic measurements in atmospheric methane obtained from the NOAA CCGG Cooperative Air Sampling Network. Recent developments at INSTAAR, University of Colorado have brought on line the capability to measure hydrogen deuterium ratios in methane using continuous flow mass spectrometry coupled with an extraction combustion sample preparation system. Preliminary results show reproducibility of cylinder air samples to less than ± 2 ‰. Data from several months of samples from six network sites are presented, including data from: Barrow and Cold Bay, Alaska, U.S.A; Tutuila American Samoa; Black Sea, Constanta, Romania; Park Falls Wisconsin, U.S.A.; and Baltic Sea, Poland.

In recent years our knowledge of gas exchange across the air-sea interface at the process level has improved as a consequence of new instrumentation and novel use of injected and natural tracers.  However, there remains significant uncertainty in the extrapolation of these results to larger scales, especially for studies focusing on global-scale processes such as the earth's carbon cycle.

The results of atmospheric CO₂, CH₄ and CO measurements are presented. The measurements were made in air samples collected at heights of 4, 25, 100, 200 and 300 m above ground, and in the atmospheric column in Obninsk, Russia (55.11 N, 36.57  E, 183 m asl).

The decadal variability of air-sea CO₂ fluxes is poorly known in the southern hemisphere. To evaluate the changes or stability of these fluxes over several years, we compare seasonal observations obtained in 1991 and 2000 the Southern Indian Ocean. For summer and winter, we observed a significant increase of ocean fugacity (fCO₂) in subtropical waters (20°-35°S), about the same rate as in the atmosphere. In polar waters south of 40°S where meso-scale biological activity is high in summer, the rising of oceanic fCO₂ is only well detected when comparing austral winter data. The decadal evolution of fCO₂ observed in the cold waters certainly results from anthropogenic CO₂ emissions, but is also probably modulated by variations of primary production.

Physical processes in the Southern Ocean are known to profoundly impact the global carbon cycle, but this region is one of the most difficult to simulate consistently in ocean general circulation models (OGCMs). Here we show that Southern Hemisphere winds, by altering the volume of light, actively-ventilated ocean water as well as the relative contribution to this volume from Ekman transport, exert strong control over both the magnitude and distribution of anthropogenic carbon uptake in an OGCM. These results are provocative in suggesting that climate warming, by increasing the magnitude of the wind stress at high southern latitudes, may act as a negative feedback on the global carbon cycle.

Accurate estimates of the spatial distribution of pre-industrial and anthropogenic air-sea carbon fluxes are crucial to understanding the processes driving ocean carbon uptake. We present regional anthropogenic and pre-industrial air-sea fluxes estimated separately from their reconstructed concentrations and Ocean General Circulation Models (OGCM). The ocean interior carbon transports required to explain these fluxes are calculated and their implications for the global carbon cycle are discussed.