DEFINING THE PROBLEM

Greenhouse Gases and Climate Change

Coal and Smokestacks When fossil fuels are burned to produce electricity, heat buildings, or fuel vehicles, greenhouse gasses are released. Fossil fuels currently account for roughly 85 percent of current US fuel use and are the primary source of energy in the US (U.S. Department of Energy. “Fossil Fuels”). In 1988, the United Nations Environment Programme and the World Meteorological Organization created the Intergovernmental Panel on Climate Change (IPCC) to examine the science of global climate change. The IPCC issues periodic reports; their most recent statement, the Fourth Assessment Report concluded that:

Atmospheric concentrations of the greenhouse gasses carbon dioxide, methane, and nitrous oxide are the highest experienced for at least 650,000 years. The sustained rate of increase in radiative forcing ["global warming"] over the past century due to these gasses is unprecedented in at least the last 20,000 years. ... Observed increases in [greenhouse gasses] and their associated warming effect are directly linked to fossil fuel use, agriculture, land use change, and other human activities. ... Human activities since 1750 have very likely exerted a net warming effect on climate. See http://www.mnp.nl/ipcc/ for the full Report.

 

The Fourth Assessment Report also predicted an increase in heat waves, extreme precipitation events, droughts in low latitudes, hurricanes, and sea level rise within our lifetime. Climate change is today arguably the most grave of a diverse and inter-related number of critical environmental stresses that are undermining our most precious relationship - the relationship that humanity has with the biosphere that supports all life. For more information, please see: http://www.ipcc.ch/ and www.grida.no/climate/vital

IPCC Summary of Temperature Trends

The nine warmest years over the last 100 years occurred during the past decade. The rate of warming during the 20th century was probably the strongest of any 100-year period in the last 1000 years.

IPCC Summary of Climate Change Patterns