The ABCs of Global Climate Change

The document outlines the role of human activity in increasing greenhouse gas emissions and global warming, the resulting environmental and health risks, and the emission reduction targets required to limit temperature increases to 1.5 or 2 degrees Celsius by 2050.

• Human activity has caused greenhouse gas (GHG) emissions and atmospheric concentrations to reach levels higher than any other period in human history, with concentrations higher than at any time in the last 800,000 years. Fossil fuel combustion and industrial processes accounted for over 75% of the approximately 49 Gigatonnes of GHGs emitted in 2010.
• Climate change has already increased the frequency of heat waves in some areas, raised heat-related deaths, increased extreme precipitation and flooding risks, and elevated sea levels since 1970. Future projections for the 21st century include increased ocean acidification, melting glaciers and permafrost, higher extinction risks for species, and threats to food and water security.
• To limit global temperature increases to 2 degrees Celsius, annual GHG emissions must be reduced by 40% to 70% of 2010 levels by 2050; limiting the increase to 1.5 degrees requires a reduction of 70% to 95% by the same date.
• Achieving a stable climate requires transitioning from coal and fossil fuels to low-carbon electricity (such as wind, solar, and hydroelectricity), increasing the share of low-carbon supply from approximately 30% to over 80% by 2050. These transitions, along with energy efficiency and shifts to public transit or cycling, provide health co-benefits through improved air quality and increased physical activity.

APA

Perrotta, K. (2016). The ABCs of Global Climate Change. Canadian Association of Physicians for the Environment. https://cape.ca/the-abcs-of-global-climate-change/

Chicago

Perrotta, Kim. The ABCs of Global Climate Change. Canadian Association of Physicians for the Environment, 2016. https://cape.ca/the-abcs-of-global-climate-change/.

Wikipedia

{{cite report |last1=Perrotta |first1=Kim |title=The ABCs of Global Climate Change |publisher=Canadian Association of Physicians for the Environment |date=17 February 2016 |url=https://cape.ca/the-abcs-of-global-climate-change/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{perrotta2016abcs, author = {Perrotta, Kim}, title = {{The ABCs of Global Climate Change}}, institution = {Canadian Association of Physicians for the Environment}, year = {2016}, month = feb, url = {https://cape.ca/the-abcs-of-global-climate-change/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }