What now? If governments are unwilling to lead when leadership is required, people must. We need a global grass-roots movement that tackles climate change and its fallout. In Australia, one initiative aims at getting one million women to take small steps in their everyday lives to cut emissions. In India, there is a project to bring solar energy to slums, which also creates green jobs. In Guatemala, women farmers are planting trees to sequester carbon and improve cultivation techniques. In Mexico, the “ecocasa” program is unlocking funds to build energy-efficient housing.

Despite these encouraging initiatives, citizens need to press their governments to come up with ambitious sustainable solutions, not just makeshift ones. Climate change must inform any new policy, whether in the development or the energy sector. It must determine the way we build our houses and the way we structure our economy. Green thinking cannot be the sole responsibility of a few environmentally minded activists, while the rest of us go on living as if there were no tomorrow.

The science behind climate change, after all, is clear. As the Intergovernmental Panel on Climate Change, the leading global body for the assessment of climate change, has unequivocally stated: “Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and oceans have warmed, the amounts of snow and ice diminished, sea level has risen, and the concentrations of greenhouse gases have increased.”

To those who argue that global warming is just the way of nature and not in any way related to human activity, the panel responds, “It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century.” The dominant cause. Not just one among many.

As a consequence, we will witness more extreme weather patterns such as droughts, storms, floods and heat waves. As we saw, just days before the Warsaw conference, with the devastating effects of Typhoon Haiyan in the Philippines, those who bear the brunt are the poorest and most vulnerable. We should also expect to witness a dramatic increase of various infectious diseases, especially vector-borne diseases such as malaria or dengue fever.