How to cut your GHG emissions to avoid climate catastrophe

In a previous article, “IPCC forecasts unavoidable climate change damage to oceans, food and Asia,” we looked at how much worse the outcomes for the world will be the higher the degree of global warming. In the second part of its Sixth Assessment Report, the Intergovernmental Panel on Climate Change says that whether global warming will be limited to 1.5 °C in the near term (2021-2040) depends on our actions and how quickly we take them. To prevent the worst ecosystem breakdowns and human suffering, greenhouse gas emissions have to be reduced, immediately. In this article, we look at how to do that.

Where does greenhouse gas come from?

Let’s first look at where greenhouse gases (GHG) come from. According to Our World in Data, the bulk of them come from two areas; 73.2% from energy use, and 18.4% from agriculture, forestry and land use.

Carbon dioxide (CO₂) is probably the first GHG that springs to mind. It accounts for 74.4% of global GHG emissions. It is caused by the use of fossil fuels and through agriculture. Another type of GHG is methane. It is released mainly through livestock, such as manure and gastroenteric releases, and it accounts for 17.3% of total GHG emissions. According to the UN Environmental Programme, “Methane has accounted for roughly 30% of global warming since pre-industrial times and is proliferating faster than at any other time since record-keeping began in the 1980s.” Methane is also 28 times more effective at trapping heat, which heightens concern about its effect on global warming.

Changing our actions to cut GHG emissions from energy use

To reduce GHG emissions, we need to revise the use of energy in our daily lives. When it comes to the shift to renewable energy from fossil fuels, Japan has said that it aims to increase the amount of electricity generated via renewable energy to about 37% by 2030. Converting our energy-generating systems to sustainable resources is an important action. Help create that change by switching your electricity provider to one that uses renewable resources.

If you have heard of the 3R principle of reduce, reuse and recycle, you will know that the first thing we need to do is to reduce our energy use. The simplest way to do that is to ditch the car and use public transport instead. As someone who was raised in the countryside of Japan, I know it is not easy to let go of your car, since most of the time it may be the only transportation option. But how about trying car sharing? And cycling is not only good for the environment, but also for your health.

Last, but not least, let’s talk about air travel. Aviation accounts for 1.9% of all energy-related GHG emissions. The number looks rather small, but scientists suggest that is due to gross inequality in its use. Roughly 80% of the world’s population has never flown. This indicates that the emissions per person who flies are sizable. That means that each individual can make a large impact by using air travel less.

Reducing GHG emissions through our diets

Agricultural development has improved food security and increased the standard of living for many. However, in order to continue enjoying rich and varied diets, we need to stop and take stock now, and start planning for sustainable development.

Unsustainable agricultural expansion led by unbalanced diets exposes ecosystems and humans to risks. In this context, a “balanced diet” refers to plant-based foods, including coarse grains, legumes, fruits, vegetables, nuts and seeds, and animal-sourced food produced in sustainable and low-GHG emission systems.

The following set of data shows why balanced diets are mainly plant-based foods. Supporting the current global diet requires 4.13 billion hectares of land for crops (1.24 billion ha) and more than double that for pasture (2.89 billion ha). Of the total area of cropland, 43% is used to grow animal feed. Of pasture land, 60% is non-arable. The argument that raising livestock is an efficient use of non-arable land falls flat because the animals are being given feed to compensate for their natural diets from pasture.

As mentioned above, methane is emitted by livestock, particularly cows, as well as by the manure and fertilizers used to produce their feed. So what would happen if we stopped eating beef? We could reduce land use by nearly 2 billion hectares. If we were to then also stop consuming mutton and dairy products, we would slash land use by another billion hectares. This means there would be more land available to nurture plants that absorb GHGs.

Culturally for Japanese people, the pescatarian diet may be relatively easy to adopt. Historically, most Japanese have been pescatarian. Roughly 80 years ago, the average consumption of meat was less than three grams a day in Japan.

In a historical context, vegetarian and vegan diets are also familiar to Japan. Shojin cuisine is traditional vegan food developed by Japanese Buddhism monks. Seasonal vegetables and wild plants give it variety. So, history shows us that widespread adoption of such diets is doable, and good for our health. Recent studies show that the health benefits of a vegetarian diet include lower risk of cancer and diabetes. Natural, healthy eating is something we can all start today.

Another good strategy to reduce energy use and resource consumption is to take good care of the things that you make and buy. From clothing and electronic devices through to vehicles, it requires energy and materials to make things. Start by checking out second-hand shops near you and other methods of reuse.

We hope this article inspires you to think about what you can do to reduce climate change and the catastrophic events it is causing. Although the impact of each of our single actions might be small, together they can create big change. Each of us is responsible for making changes for the better.