climate change
These measures could limit global warming
The energy transition also plays an important role in limiting climate change (symbol image).
© Julian Stratenschulte / DPA
The Intergovernmental Panel on Climate Change has published new scientific bases on climate change and its risks for humanity. The task now is to limit global warming. What could work?
The earth continues to heat up. The Intergovernmental Panel on Climate Change (IPCC) has been warning of the effects of man-made climate change for years. On April 4, the Council will present the third part of the new progress report. The main focus is on how global warming can be reduced. Mitigation is understood to mean all measures to reduce climate change and its consequences. Some possibilities and ideas:
Produce energy with fewer fossil fuels
Carbon dioxide (CO2) accounts for around 80 percent of the greenhouse gases released. It mainly occurs when coal, oil and gas are used to generate energy. The use of renewable energies is therefore an important measure, such as wind and solar power as well as bio or other CO2-neutral fuels. But there are limitations: For example, it can be problematic to create huge palm oil or rapeseed fields for fuel production. The area is lost for the cultivation of food, and in such plantations the biodiversity, which is vital for nature and humans, decreases.
There are other methods too. The Swiss company Synhelion, for example, uses sunlight to produce a synthesis gas from which kerosene is made. According to the company, as much CO2 is released during combustion as was bound during production. The Swiss airline should fly with it in 2023. “Green hydrogen, green gas, that’s the way to go in my opinion,” says Ottmar Edenhofer, director of the Potsdam Institute for Climate Impact Research. Green hydrogen is obtained by electrolysis using renewable energy and can replace fossil fuels. Green gas is biogas made from agricultural waste.
More efficient use of energy
This includes ventilation, cooling, lighting and motors that use less energy. “Private households are responsible for a good quarter of electricity consumption,” writes the Institute for Energy and Environmental Research in Heidelberg. You can also save energy with water-saving fittings on taps and shower heads: This reduces the hot water flow and less energy is required for hot water. It is also more energy-efficient if commuters join together to carpool instead of driving individually in their own cars. Improved building insulation can save fuel for heating.
Changes in mobility, consumption and nutritional behavior
Fewer car journeys and flights, more cycling and train travel, an electronic newspaper instead of a paper newspaper, video conferences instead of business trips, home office instead of working in the company – all of this reduces CO2 emissions. Eat less meat too: cattle, for example, emit the climate-damaging gas methane, CO2-storing forests are cut down to create new pastures or fields – and other greenhouse gases are released during the production of animal feed, for example as a result of fertilization.
Bind CO2 or remove it from the atmosphere and store it
This can be done, for example, through reforestation or the renaturation of moors, because both absorb a lot of CO2. Cultivating CO2-storing plants such as trees, rapeseed or corn, then burning them in biogas plants to produce electricity and capturing the resulting CO2 and storing it underground: Climate science calls such processes BECCS (Bioenergy with Carbon Capture and Storage). Another idea that researchers at the University of Augsburg have developed as a computer model: basalt dust scattered over natural landscapes can bind a lot of CO2 during weathering. Researchers are also examining ways of storing carbon dioxide on the sea floor or promoting the growth of plankton in the sea in order to bind carbon.
The Swiss company Climeworks commissioned one of the largest systems for removing CO2 from the atmosphere in Iceland in 2021. The CO2 is mixed with water and pumped into the ground. The system is operated with CO2-neutral geothermal energy. Sabine Fuss, an expert in sustainable resource management at the Humboldt University in Berlin, warns that CO2 removals are not a silver bullet: “Such removals can never be a substitute for reducing emissions.”
reduce solar radiation
Another approach of the so-called geoengineering describes methods with which the solar radiation hitting the earth is to be reduced. This could happen, according to models, with sulfur particles sprayed 15 to 20 kilometers above the earth, or with aerosols reflecting sunlight. The Federal Environment Agency warns: “These so-called geoengineering measures have one thing in common: they harbor risks for people and the environment that could have a global impact.” Fuss also says there is a lack of research. But in order to prevent catastrophic warming, intervention in the radiation balance cannot be brushed aside. “We cannot afford larger knowledge gaps in the field in the long term,” she says.