The world not only continues to build new coal-fired power plants, but built more new coal plants in the past decade than in any previous decade. Worldwide, an average of 89 gigawatts per year (GW yr-1) of new coal generating capacity was added between 2010 and 2012, 23GWyr-1 more than in the 2000–2009 time period and 56GWyr-1 more than in the 1990–1999 time period. Natural gas plants show a similar pattern. Assuming these plants operate for 40 years, the fossil-fuel burning plants built in 2012 will emit approximately 19 billion tons of CO2 (Gt CO2) over their lifetimes, versus 14 Gt CO2 actually emitted by all operating fossil fuel power plants in 2012.
Too Much to Ask: Why Small Modular Reactors May Not Be Able to Solve the Problems Confronting Nuclear Power
Over the last few years, much hope has been invested in what are called Small Modular Reactors (SMRs) as a possible way to address some of the key problems with existing nuclear reactor designs and fuel cycles and thereby offer a brighter future for nuclear power. Several countries are in the fray to develop SMRs, including the United States, Russia, China, France, Japan, South Korea, India, and Argentina. Several of these countries are providing substantial government support for such reactors. Regulatory agencies in these countries are also in the process of grappling with licensing SMRs, many of which incorporate novel features in their designs.
This article introduces the Climatic Change special issue dedicated to negative emissions technologies, also known as carbon dioxide removal (CDR) from the atmosphere. CDR is the only class of mitigation options able to reduce the carbon stock in the atmosphere significantly. In this special issue CDR is explored from the perspectives of integrated assessment, technology optimization, environmental science, and political science.
Climate adaptation and flood risk assessments have incorporated sea-level rise (SLR) projections developed using semi-empirical methods (SEMs) and expert-informed mass-balance scenarios. These techniques, which do not explicitly model ice dynamics, generate upper bounds on twenty-first century SLR that are up to three times higher than Intergovernmental Panel on Climate Change estimates. However, the physical basis underlying these projections, and their likelihood of occurrence, remain unclear. Here, we develop mass-balance projections for the Antarctic ice sheet within a Bayesian probabilistic framework, integrating numerical model output and updating projections with an observational synthesis.Without abrupt, sustained, changes in ice discharge (collapse), we project a 95th percentile mass loss equivalent to ~13 cm SLR by 2100, lower than previous upper-bound projections.
In 1958, Charles David Keeling began measuring the concentration of carbon dioxide (CO2) in the atmosphere, at a site 11,000 feet above sea level near the top of Mauna Loa on the “big island” of Hawaii. The time series of monthly averages, the “Keeling Curve,” is the iconic figure of climate change (see Figure 1). The curve oscillates and rises. The annual oscillations (whose details are seen in the Figure’s inset) are the consequences of the seasonal breathing of the northern-hemisphere forests, which remove CO2 from the atmosphere during their growing season and return CO2 to the atmosphere as their leaves decay on the forest floor in winter.
The report finds that the significant risks that climate change poses to human society and the environment provide a strong motivation to move ahead with substantial response efforts. Current efforts of local, state, and private sector actors are important, but not likely to yield progress comparable to what could be achieved with the addition of strong federal policies that establish coherent national goals and incentives, and that promote strong U.S. engagement in international-level response efforts.
The American Physical Society has produced a technical assessment on the direct air capture of CO2 with chemicals to better inform the scientific community on the technical aspects of removing carbon dioxide from the atmosphere. Robert Socolow served as a co-chair of the DAC study. Technical References)(
This report asserts that, unless man-made carbon dioxide emissions are substantially curbed or atmospheric carbon dioxide is controlled by some other means, the oceans will continue to become more acidic. Although the long-term consequences are unknown, a federal program under development is a positive move toward understanding and responding to the problem.