At-a-glance guide to the IPCC’s Fifth Assessment Report findings on physical science

This guide, authored by Dr Qamar Chaudhry of the Climate and Development Knowledge Network (CDKN), outlines key findings from the first section of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) regarding the physical science of climate change.

• Evidence has strengthened since the Fourth Assessment Report (AR4) that global climate change is primarily caused by human-induced increases in greenhouse gas concentrations, affecting regional temperatures, the water cycle, the cryosphere, oceans, and the global energy budget.
• The Earth has experienced a radiative imbalance since at least 1970, with more solar energy entering than exiting the atmosphere. Globally-averaged land and ocean surface temperatures rose by approximately 0.8°C from 1901 to 2010 and about 0.5°C from 1979 to 2010, although the rate of warming slowed between 1998 and 2012 compared to the trend since 1951.
• Global mean sea level is rising unequivocally, with an increase of 1.4 to 2.0 mm per year during the 20th century and 2.7 to 3.7 mm per year since 1993, driven primarily by glacier mass loss and ocean thermal expansion.
• Changes in the water cycle since 1950 are attributable to human influence. While global land-based precipitation has shown little change since 1900, future 21st-century increases will be non-uniform, with more precipitation likely in moist mid-latitude regions and less in arid and semi-arid mid-latitude regions.
• Other physical changes include the continued global shrinkage and mass loss of glaciers, the acidification of seawater due to the uptake of anthropogenic CO2, and a global increase in warm days and nights alongside a decrease in cold days and nights between 1951 and 2010.

APA

Chaudhry, Q. (n.d.). At-a-glance guide to the IPCC’s Fifth Assessment Report findings on physical science. Climate and Development Knowledge Network. https://cdkn.org/story/feature-at-a-glance-guide-to-the-ipccs-fifth-assessment-report-findings-on-physical-science

Chicago

Chaudhry, Qamar. At-a-glance guide to the IPCC’s Fifth Assessment Report findings on physical science. Climate and Development Knowledge Network, n.d. https://cdkn.org/story/feature-at-a-glance-guide-to-the-ipccs-fifth-assessment-report-findings-on-physical-science.

Wikipedia

{{cite report |last1=Chaudhry |first1=Qamar |title=At-a-glance guide to the IPCC’s Fifth Assessment Report findings on physical science |publisher=Climate and Development Knowledge Network |url=https://cdkn.org/story/feature-at-a-glance-guide-to-the-ipccs-fifth-assessment-report-findings-on-physical-science |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{chaudhryndataglance, author = {Chaudhry, Qamar}, title = {{At-a-glance guide to the IPCC’s Fifth Assessment Report findings on physical science}}, institution = {Climate and Development Knowledge Network}, url = {https://cdkn.org/story/feature-at-a-glance-guide-to-the-ipccs-fifth-assessment-report-findings-on-physical-science}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }