Maria Jos Sanz Ernst Detlef Schulze and Riccardo Valentini

Climate change is one of the most significant sustainable development challenges facing the international community. It has implications not only for the health and well-being of the Earth's ecosystems, but also for the economic enterprises and social livelihoods that we have built upon this base. Creative responses based on solid research, shared knowledge, and the engagement of people at all levels are required to meet the challenge posed by climate change. International agreements are one of...

Louis Lebel

To achieve CO2 stabilization in the atmosphere within the next century will require profound social changes in a world where most societies have already become, or aspire to be, carbon cultures. Culture is understood as a critical set of institutions that guide the ideas by which a society lives. Culture penetrates market, political, and other institutions and is far more than a grab-bag for all those factors that are not about economics or politics. In carbon cultures, much behavior and...

Terrestrial Biological Sequestration and Disturbance Reduction

In equation (3), these options reduce emissions from FLULUC and promote CO2 uptake in the land component of FSq. Reforestation, Afforestation, and Land Restoration The potential global carbon sequestration due to increased forest extension and other land uses is in the order of 1 PgC y-1 by 2010 (Watson et al. 2000b). In the past few decades major plantation has occurred in many countries, often where previous deforestation took place. During the 1990s alone, the global area of plantations...

NonCO2 Trace Gas Connections

Rising concentrations of a large number of potent anthropogenic greenhouse gases other than carbon dioxide have collectively contributed an amount of radiative forcing comparable to that of CO2 since preindustrial times. Many of these non-CO2 gases (e.g., CH4, N2O, CF2O2, SF6) are emitted at the Earth's surface and contribute directly to this forcing (Prinn, Chapter 9, this volume). They are characterized by atmospheric lifetimes of decades to millennia (lifetime as used here is the amount of...

Human Systems

Composition World Energy Consumption

Humans have had a profound impact on carbon cycling in the atmosphere, the terrestrial biosphere, and, to a lesser extent, the oceans. To understand how humans will continue to interact with these reservoirs in the future, one must understand the drivers responsible for how humans interact with the environment. Energy use has historically been viewed as an essential commodity for economic growth. The paradigm of grow or die historically meant increasing demands for additional resources and a...

The Vulnerability of the Carbon Cycle in the 21st Century An Assessment of Carbon ClimateHuman Interactions

Nicolas Gruber, Pierre Friedlingstein, Christopher B. Field, Riccardo Valentini, Martin Heimann, Jeffrey E. Richey, Patricia Romero Lankao, E.-Detlef Schulze, and Chen-Tung Arthur Chen In most scenario calculations to date, emissions from fossil-fuel burning are prescribed, and a carbon cycle model computes the time evolution of atmospheric CO2 as the residual between emissions and uptake by land and ocean, typically without considering feedbacks of climate on the carbon cycle (see, e.g.,...

Current Status and Past Trends of the Global Carbon Cycle

Christopher L.Sabine, Martin Heimann, Paulo Artaxo, Dorothee C. E. Bakker, Chen-Tung Arthur Chen, Christopher B. Field, Nicolas Gruber, Corinne Le Quere, Ronald G. Prinn, Jeffrey E. Richey, Patricia Romero Lankao,Jayant A. Sathaye, and Riccardo Valentini In a global, long-term perspective, the record of atmospheric CO2 content documents the magnitude and speed of climate-driven variations, such as the glacial-interglacial cycles (which drove CO2 variations of 100 parts per million ppm over...

R1l

Time series of anomalous non-fossil-fuel net land-atmosphere flux from the inversion (solid line, PgC y-1) compared with fire counts compiled by the European Space Agency (dashed line, arbitrary scale), both aggregated over two continental areas (R denbeck et al. 2003). Figure 8.4. Time series of anomalous non-fossil-fuel net land-atmosphere flux from the inversion (solid line, PgC y-1) compared with fire counts compiled by the European Space Agency (dashed line, arbitrary scale),...

Within River Transport and Reaction Processes

Within-river transport processes carry these eroded materials downstream through the river network. Transport is not passive significant transformations occur along the way. Rivers exchange with their floodplains (depending on how canalized and diked a river is). The movement of POC is, of course, directly linked to the movement of suspended sediments. Sediments are deposited and remobilized multiple times and over long timescales. In the Amazon, for example, Dunne et al. (1998) computed that...

Reservoir Connections

The background chapters in this volume discuss the various carbon reservoirs and the processes relevant to controlling atmospheric CO2 and related trace gas concentrations. To appreciate the Earth's carbon cycle and its evolution, it is necessary to exam ine the connections among the various carbon pools. This analysis must be done within a framework that provides an integrated perspective across both disciplinary and geographic boundaries, with particular emphasis on the carbon cycle as an...