Description: The purpose of this report is to compile and summarise the present knowledge on impacts of climate change as a basis for a consideration of what may constitute dangerous anthropogenic interference with the climate system under Article 2 of the United Nations Framework Convention on Climate Change (UNFCCC). An attempt will be made to associate projected global mean surface temperature and/or sea level changes with specific identified impacts and effects in order to assist a discussion on the operationalization of Article 2. The main emphasis will be on ecosystem effects, food production, water resources, and sustainable development.

Description: Scientists offer comments on the Climate Change Science Program Strategic Plan

Description: The Clean Water Act (CWA) establishes the basic structure for regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters. The basis of the CWA was enacted in 1948 and was called the Federal Water Pollution Control Act, but the Act was significantly reorganized and expanded in 1972. "Clean Water Act" became the Act's common name with amendments in 1977. Under the CWA, EPA has implemented pollution control programs such as setting wastewater standards for industry. We have also set water quality standards for all contaminants in surface waters. The CWA made it unlawful to discharge any pollutant from a point source into navigable waters, unless a permit was obtained. EPA's National Pollutant Discharge Elimination System (NPDES) permit program controls discharges. Point sources are discrete conveyances such as pipes or man-made ditches. Individual homes that are connected to a municipal system, use a septic system, or do not have a surface discharge do not need an NPDES permit; however, industrial, municipal, and other facilities must obtain permits if their discharges go directly to surface waters.

Description: From the perspective of terrestrial ecosystems, the most important component of global change over the next three or four decades will likely be land-use/cover change. It is driven largely by the need to feed the expanding human population, expected to increase by almost one billion (109) people per decade for the next three decades at least. Much of this increase will occur in developing countries in the low-latitude regions of the world. To meet the associated food demand, crop yields will need to increase, consistently, by over 2% every year through this period. Despite advances in technology, increasing food production must lead to intensification of agriculture in areas which are already cropped, and conversion of forests and grasslands into cropping systems. Much of the latter will occur in semi-arid regions and on lands which are marginally suitable for cultivation, increasing the risk of soil erosion, accelerated water use, and further land degradation.

Description: This document provides a summary of a study by NOAA researchers and National Institute for Space Research in the Netherlands. According to the study, one of the atmosphere's most potent greenhouse gases, methane, may now have leveled off. Scientists aren't sure yet if this "leveling off" is just a temporary pause in two centuries of increase or a new state of equilibrium.