Global warming occurs because greenhouse gases, such as carbon dioxide, accumulate and prevent Earth’s heat from escaping. The IPCC, a UN-supported body involving more than 195 countries, rigorously reviews scientific studies and publishes assessment reports every five to seven years. These reports synthesize observations, future projections, impact analyses, and mitigation options, serving as the backbone of national climate policies. Former U.S. Vice-President Al Gore translated complex data into compelling stories through the documentary "An Inconvenient Truth" and a worldwide lecture tour. Their combined efforts fueled public support for international negotiations, from the Kyoto Protocol to the later Paris Agreement, and framed climate change as a security risk that can trigger conflict and poverty—an angle that fits the Peace Prize mandate.

The IPCC’s Fourth Assessment Report (AR4, 2007) famously stated that "warming of the climate system is unequivocal" and quantified the probability that anthropogenic CO₂ emissions are the main driver of post-industrial temperature rise at over 90 %. AR4 integrated evidence from global atmospheric-ocean observing systems, coupled climate models (CMIP3), and impact-adaptation-vulnerability (IAV) studies. Acting as a policy–communication bridge, Al Gore visualized carbon footprints, the economic feasibility of renewable energy investment, and national emission trends, thereby personalizing climate issues for citizens. His approach has become a classic case study in science communication, risk perception psychology, and media studies. Consequently, climate change has been reframed from a purely environmental topic into a cross-cutting challenge spanning economics, diplomacy, and security.

AR4 WG1 employed multivariate data assimilation and energy-balance diagnostics to attribute ~+1.6 W m⁻² radiative forcing in the late 20th century predominantly to GHG sources. Scenario studies provided a 2.4 K envelope between SRES A1FI and B1 pathways, explicitly quantifying uncertainties from climate sensitivity distributions and carbon-cycle feedbacks. WG2/3 supplied cost–benefit analyses of impacts and mitigation, highlighting how social discount rates strongly shape outcomes. Gore’s fusion of quantitative graphics with narrative expanded the policy window and elevated the political visibility of mechanisms such as REDD+ and emissions trading schemes. Collectively these efforts empirically substantiate the cooperative model between epistemic communities and advocacy coalitions discussed in climate-governance literature.