For over a century, scientific research has confirmed that human-induced greenhouse gas (GHG) emissions are fundamentally altering Earth’s climate. This perspective moves beyond broad climate science to deliver a focused assessment of how these emissions directly threaten human health, well-being, and societal stability.
The scale of the problem is accelerating. According to the Intergovernmental Panel on Climate Change (IPCC), global annual GHG emissions reached approximately 59 gigatons of CO2 equivalent (Gt/y) in 2022. The preceding decade (2010-2019) saw an average of 56 Gt/y—a 16% increase over the 2000-2009 period and the largest decadal rise in atmospheric concentrations in the modern era.
A Synthesis of Converging Evidence:
This analysis is grounded in a comprehensive synthesis of evidence, including long-term climate records, advanced modeling, attribution science, and public health data. A key strength of this approach is the consistent convergence of insights from these diverse fields, all pointing to the same conclusion: human activities are destabilizing the climate system with profound consequences for individuals and communities.
Substantial progress in detection and attribution science since 2009, bolstered by extended datasets on sea-level rise, wildfires, and extreme heat, has strengthened our ability to link specific impacts to human causation.
Alignment and Distinction with Global Consensus
This perspective aligns with the global scientific consensus, particularly the IPCC's Sixth Assessment Report, on findings related to extreme weather and ecosystem disruption. However, it offers a distinct, dual focus: it contributes to the global understanding while deliberately highlighting the impacts on health, infrastructure, and communities within the United States, framing these domestic risks within their worldwide context.
Key Contributions and Future Directions
A central contribution of this work is its emphasis on climate “tipping points,” reflecting the latest understanding in Earth system science. To build upon this foundation, future priorities must include:
Conducting regional risk assessments to address local vulnerabilities.
Evaluating the real-world effectiveness of adaptation strategies.
Investigating the intersection of climate change and social inequality.
Improving models to capture compound risks, such as heatwaves amplified by drought and air pollution.
Conclusion
While this synthetic approach—essential for informing policy—necessarily involves simplification and may not explore all regional uncertainties in depth, the core conclusions are robust. The evidence presents a clear and pressing message: human-caused greenhouse gas emissions pose a significant and immediate threat to the health, safety, and well-being of people worldwide, demanding an urgent and decisive response.