The Attribution Question

Knowing that temperatures are rising does not automatically prove humans caused it. Attribution science answers that question rigorously. Scientists build climate models that include both natural factors (solar cycles, volcanic eruptions) and human factors (greenhouse gas emissions, aerosols).

The "fingerprint" evidence is especially compelling. Human-caused warming predicts specific patterns: nights warming faster than days, winters warming faster than summers, the upper atmosphere cooling while the lower atmosphere warms.