“Climate Farm” Strategy Faces Hurdles: Research reveals the potential for limited carbon capture within safe limits

Plant rapidly growing crops, burn them, capture and store released CO2. This is being discussed as a way to remove greenhouse gases from the atmosphere and limit global heating to 1.5 degrees in the long term. However, if this is done on land beyond existing agriculture, it puts the stability of the biosphere at risk.

Research from Communications Earth & Environment’s Potsdam Institute for Climate Impact Research (PIK) shows numbers on the potential of such a new “climate farm,” also known as bioenergy with carbon capture and storage (BECCS). . This study also considered the boundaries of other planets, as well as carbon balance.

Under the assumptions of research on plant species productivity (new varieties over time, medium climate change), the potential outside of existing farmland is less than 200 million tonnes of carbon dioxide removal in 2050. Climate scenario.

This means that if you want to rely on this carbon removal method rather than potential alternatives such as air filter systems or weathering reinforced rocks, you will need to use existing farmland. This is only possible if our food system is changing and is not particularly focused on animal products.

The research team began with the concept of planetary boundaries developed in 2009 under the leadership of current PIK director Johann Rockstrom. Boundaries represent the important limitations of nine processes that form the basis of human life, from climate to forest and ocean conditions to biodiversity.

As the first planetary health check announced by PIK recently showed, six boundaries have already been violated. Four of them are land-related and related to the allocation and management of climate farms. They are associated with loss of biosphere integrity caused by fertilization, freshwater cycles, deforestation, for example, reduced biodiversity. New research provides the first systematic, process-based modelling of how the possibilities of BECC are constrained if not further exceed these important limitations.

“Our computer simulations are one of the most sophisticated applications of the biosphere model developed by PIK to date,” said Wolfgang Lucht, head of Earth Systems Analysis Research and co-author of the study. I’ll explain it.

“It provides important insight into the current climate debate. Given the fact that the 1.5 degree limit is currently exceeded, we will not only provide a CO2 balance in public policy, but also the final one in response to the climate crisis. Look at the boundaries of other planets. This study was part of the four-year EU project negham on responsible negative emissions.

In theory, if all biophysically appropriate regions other than today’s agriculture have been converted, the likelihood of carbon removal via climate farms is significantly higher than would be expected in most climate scenarios. It will become. These scenarios assume an average of approximately 7.5 billion tonnes of carbon removal in 2050. This means limiting global heating to 2 instead of 1.5 degrees. However, if planetary boundaries are considered, the picture is reversed. Billions of tonnes are not achievable with this technology.

The LPJML Global Biosphere Model, which simulates daily water, carbon and nitrogen flows with daily water, carbon and nitrogen flows, shows how each of the four constraints affects the potential of carbon removal. Masu. To the theoretical upper limit. Reduce it by 59% with freshwater systems protection. Restrictions on deforestation will result in a 61% reduction. Avoiding further loss of biosphere integrity by as little as 93%.

Assuming that existing forests are explicitly protected and all four planetary boundaries are respected, model studies show the possibility of removing less than 200 million tons of CO2 in 2050.

“All the most important climate protection strategies remain to rapidly reduce emissions to zero,” concludes Johanna Brown, a PIK researcher and lead author of the study. . “To increase the geographical range of climate farms and therefore the possibility of carbon removal, the world must be in time for less space for agriculture. For example, more plant-based diets around the world are theoretical. It can release pasture areas that are important to others. Use it.”

Therefore, this study points out important connections and highlights Brown. “Producing and consuming less animal products not only helps the climate by reducing agricultural emissions, but also mitigates the struggle against scarce resources, thereby protecting the entire Earth system.”