Climate Change Fact Sheet

The document outlines Dr. James E. Hansen's testimony on climate change, highlighting that the United States is the largest source of CO2 emissions and that current 'Business-as-Usual' trends could lead to at least 5°C of warming by 2100. It warns of non-linear ice sheet disintegration in Greenland and West Antarctica, potentially causing sea level rises of 25±10 meters if warming reaches 2-3°C. Hansen argues that abrupt climate changes are practically certain under current emission trends, but an 'Alternative Scenario' could keep warming below 1°C if CO2 emissions are moderately reduced by mid-century and peak by 2100.

• The United States is the primary global contributor to CO2 emissions, producing nearly four times as much as any other single country. The fastest growing emission sources are power plants and vehicle emissions.
• Under 'Business-as-Usual' (BAU) scenarios, where CO2 concentration growth continues at typically 2% per year, global warming is projected to reach at least 5°C by 2100. Warming in the range of 2-3°C is expected to cause large-scale disastrous impacts for humans and other species.
• Global warming of 2-3°C could trigger rapid, non-linear disintegration of the Greenland and West Antarctica ice sheets. While the IPCC's baseline projection for sea level rise by 2100 was 45 cm (range 10-90 cm), a BAU scenario with 2-3°C warming could result in a sea level rise of at least 25±10 meters.
• Abrupt climate changes are considered practically certain this century if BAU emissions continue. Dr. Hansen states there is a probability greater than 99% that 2°C of additional warming would push the Earth past a tipping point, leading to major regional disruptions, species extermination, and sea level rises of several meters.
• An 'Alternative Scenario' to limit warming to below 1°C requires moderate CO2 reductions by mid-century and a sharper reduction thereafter, with concentrations peaking at approximately 475 ppm in 2100. This scenario also requires reducing other greenhouse gases, such as methane, and black carbon.

APA

Environmental and Energy Study Institute (2006). Climate Change Fact Sheet. https://www.eesi.org/files/hansen_climate_testimony_06.pdf

Chicago

Environmental and Energy Study Institute. Climate Change Fact Sheet. 2006. https://www.eesi.org/files/hansen_climate_testimony_06.pdf.

Wikipedia

{{cite report |author=Environmental and Energy Study Institute |title=Climate Change Fact Sheet |date=November 2006 |url=https://www.eesi.org/files/hansen_climate_testimony_06.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{environmentalandenergystudyinstitute2006climate, author = {{Environmental and Energy Study Institute}}, title = {{Climate Change Fact Sheet}}, institution = {Environmental and Energy Study Institute}, year = {2006}, month = nov, url = {https://www.eesi.org/files/hansen_climate_testimony_06.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }