Over the past 100 years, human activity has greatly changed the rate of atmospheric N (nitrogen) deposition in terrestrial ecosystems, resulting in N saturation in some regions of the world. The contribution of N saturation to the global carbon budget remains uncertain due to the complicated nature of C-N (carbon-nitrogen) interactions and diverse geography. Although N deposition is included in...

This paper looks at both the efficiency and distributional implications of a carbon tax and/or other energy taxes as part of a package of measures to address the budget deficit. We build a dynamic general-equilibrium overlapping-generations model (OLG) of the U.S. economy, including detail on government taxes and expenditures and a disaggregated production structure including several energy ind...

Climate warming affects permafrost soil carbon pools in two opposing ways: enhanced vegetation growth leads to higher carbon inputs to the soil, whereas permafrost melting accelerates decomposition and hence carbon release. Here, we study the spatial and temporal dynamics of these two processes under scenarios of climate change and evaluate their influence on the carbon balance of the permafros...

Introduction Conclusions References

The discovery that methane from dissociation of gas-hydrates could be an important factor in the global carbon cycle resolves the major discrepancy in estimates of the increase of terrestrial biomass from the Last Glacial period to the present. Carbon isotope budgeting using the marine carbon isotopic record results in an estimate centered around 500 GtC; whereas palaeovegetation reconstruction...

Centennial evolution of the atmospheric methane budget: what do the carbon isotopes tell us? K. R. Lassey, D. M. Etheridge, D. C. Lowe, A. M. Smith, and D. F. Ferretti National Institute of Water and Atmospheric Research, P.O. Box 14-901, Wellington, New Zealand CSIRO Marine and Atmospheric Research, PMB 1, Aspendale Vic. 3195, Australia Australian Nuclear Science and Technology Organisation, P...

The northern cryosphere is undergoing substantial warming of permafrost and loss of sea ice. Release of stored carbon to the atmosphere in response to this change has the potential to affect the global climate system. Studies indicate that the northern cryosphere has been not only a substantial sink for atmospheric CO2 in recent decades, but also an important source of CH4 because of emissions ...

In severely polluted areas, such as locally in Montshegorsk in northwestern Russia, all trees have died. However, measurements from Austria, Finland, France, Germany, Sweden, and Switzerland show a general increase of forest resources. The fertilization effects of pollutants override the adverse effects at least for the time being. Biomass was built up in the 1970s and 1980s in European forests...

arth's climate is greatly influenced by carbon dioxide conE centrations in the atmosphere, which have increased by approximately 25% since the dawning of the Industrial Revolution, when fossi l fuel combustion accelerated greatly (IPCC 1990). Another important anthropogenic source of atmospheric carbon is associated with deforestation, especially in primary forests, which can store large amount...

The flux of CO2 from the soil to the atmosphere – soil respiration (RS), is one of the least known components of the terrestrial carbon cycle. RS depends on many factors and varies substantially in time and space. High uncertainty of RS flux valuation leads to a wide range of reported carbon budget estimates for Russian forests. We developed a modeling system for assessing soil carbon stock and...