evidence: The relationship between atmospheric CO2 levels and climate change is often perceived as a controversial subject. While there’s no real disagreement among climate scientists – around 90% fully agree that human activity is clearly responsible for climate change – in the United States in 2016, barely 50% of the general public came to the same conclusion. Adding to the general confusion, highly active "climate-change deniers" claim that temperature has evolved independently of CO2 atmospheric concentrations through Earth’s history, and that therefore today’s rising CO2 levels are not an issue. So did scientists get the story wrong? No. CO2 has long contributed to controlling the Earth’s climate, and its rising concentration in the atmosphere and oceans is a major threat to humanity. [...] As a result of the pCO2 increase, the average surface temperature has already increased by almost 1°C between 1901 and 2012. The Earth’s surface has been much warmer than today in the past and it will eventually cool off. However, the consequences of the short-term changes are disastrous. In addition to higher surface temperatures, extreme weather events, ocean acidification, ice melting and sea-level rise are about to significantly disrupt our daily lives and harms the ecosystems around us.