Anthropogenic climate change is identified through a wide range of scientific indicators that collectively reveal how human activities are altering the Earth’s climate system. These indicators provide measurable evidence of changes in temperature, atmospheric composition, ocean dynamics, cryosphere conditions, and ecological patterns. One of the most important indicators is the rapid rise in greenhouse gas concentrations, particularly carbon dioxide, methane, and nitrous oxide. Measurements taken from atmospheric monitoring stations such as the one at Mauna Loa show a continuous increase in carbon dioxide levels since the industrial revolution. This rise directly correlates with fossil fuel combustion, deforestation, and industrial processes, demonstrating that human activity is the primary driver. The chemical signature of atmospheric carbon dioxide also reveals a dominance of carbon released from fossil fuels, thereby strengthening the link between anthropogenic emissions and climate change. Another major indicator is the upward trend in global surface temperatures. Temperature records from land stations, ocean buoys, and satellite observations show that the Earth has warmed significantly over the last century, with most of the warming occurring in recent decades. This warming trend cannot be explained by natural factors alone, such as volcanic activity or variations in solar radiation. Instead, climate models reveal that only when human-produced greenhouse gases are included