The explosion of the Deepwater Horizon drilling rig in the Gulf of Mexico on April 20, 2010, and the resulting oil spill began a cascade of effects on the coastal areas of the Gulf and on the wealth of species that inhabit those areas. This report addresses the importance of wetlands in general, the ecology of the coastal wetlands in the Gulf, impacts of oil spills on wetland habitats, response options, the implications of hurricane season for the spill's impacts, and cleanup and recovery issues. The emphasis is on the nearshore environment, although a few species found in deeper waters will be mentioned. In addition, some lessons from past spills such as the Exxon Valdez in Alaska will be discussed, along with issues that may arise as response and recovery transition to restoration of the Gulf.

The production of bioenergy - renewable energy derived from biomass - could potentially increase national energy security, reduce greenhouse gas emissions, and contribute to rural economic growth. This report provides analyses of commonly discussed biomass feedstocks and their relative potential for power generation. Additional biopower issues - feedstock accessibility, the biomass power plant carbon-neutrality debate, and unintended consequences of legislative activities to promote bioenergy - are also discussed.

This report focuses on the mandated minimum usage requirements - referred to as the Renewable Fuel Standard (RFS) - whereby a minimum volume of biofuels is to be used in the national transportation fuel supply each year. It describes the general nature of the biofuels RFS and its implementation, and outlines some of the emerging issues related to the sustainability of the continued growth in U.S. biofuels production needed to fulfill the expanding RFS mandate, as well as the emergence of potential unintended consequences of this rapid expansion. This report does not address the broader public policy issue of how best to support U.S. energy policy.

The diminishment of Arctic sea ice has led to increased human activities in the Arctic, and has heightened concerns about the region's future. Issues such as Arctic sovereignty claims; commercial shipping through the Arctic; Arctic oil, gas, and mineral exploration; endangered Arctic species; and increased military operations in the Arctic could cause the region in coming years to become an arena of international cooperation, competition, or conflict. This report provides an overview of Arctic-related issues for Congress, and refers readers to more in-depth CRS reports on specific Arctic-related issues.

At least one recent report and numerous news articles suggest that carbon dioxide (CO2) emissions are rising more rapidly than expected. While CO2 emissions associated with human activities continue to rise -- and may be worthy of alarm because of their influence on climate change -- any short-term comparisons between actual emissions and the Intergovernmental Panel on Climate Change (IPCC) scenarios miss the mark. This report analyzes this issue and the issues associated with IPCC scenarios and trajectories. It also describes the importance of monitoring CO2 emissions and analyzing the factors and forces behind increasing CO2 emissions.

This report discusses global climate change and the possibility that human activities are releasing gases, including carbon dioxide (CO2), at rates that could affect global climate change.