Bury the greenhouse gas
In order to limit the consequences of global warming, it is no longer enough to just reduce CO2 emissions. Mankind must also actively remove the greenhouse gas from the atmosphere. Now it is a question of finding the best mix among the various technical approaches.
Up until about a decade ago, to save the world from an all too dramatic climate change, it seemed that reducing greenhouse gas emissions would be enough. You have to replace fossil fuels with clean energy sources, make cars and buildings more efficient, switch to LED lighting, eat less meat and so on. The most important group of experts for such assessments is the IPCC, also known as the Intergovernmental Panel on Climate Change, an intergovernmental committee of the United Nations that regularly compiles the state of knowledge in climate research. As late as 2005, the IPCC considered the strategy to reduce emissions and promote renewable energies to be sufficient. But that didn't work – since then, global CO2 emissions haven't fallen, they've risen. In the meantime, such measures alone no longer help, even if the annual ones were to fall to zero.
According to experts, the devastating economic and ecological consequences of excessive climate change can only be averted with negative emissions. In concrete terms, this means that humanity has to remove billions of tons of carbon dioxide from the atmosphere every year. Large-scale negative emissions are now a "biophysical imperative," according to a 2018 study led by Jan Christoph Minx of Germany's Mercator Research Institute on Global Commons and Climate Change.
How do we get there? …
