The energy saving benefits of recycling have been touted for years, but calculations about the environmental benefits of composting are just surfacing. Recent studies confirm that composting is an effective and accessible way to reduce greenhouse gases.
Our household waste is a significant contributor to global warming, and 25% of our trash is comprised of food wastes and other materials that could be composted instead! Many people believe that throwing food scraps and paper products into a landfill is harmless because they biodegrade. However, when compostable materials such as food waste and paper decompose in the anaerobic (without oxygen) conditions of a landfill, they produce and emit methane into our air, which has 23-71 times greater heat trapping capabilities than carbon dioxide. When trash is burned, incinerators emit carbon dioxide (CO2) and nitrous oxide (N2O) into our air; N2O is a greenhouse gas 310 times more powerful in atmospheric warming than carbon dioxide.
Composting eliminates generating these greenhouse gases and has additional “upstream” benefits. Compost used on fields helps the soil sequester carbon dioxide, improves the health and workability of the soil, reduces the use of pesticides, and displaces synthetic chemical fertilizers. Fertilizer production requires intensive fossil fuel energy and seriously impacts human and environmental health. In addition, compost replenishes and revitalizes exhausted farm soils by replacing trace minerals and organic material, which reduces soil erosion and helps prevent storm water runoff.
While many strategies to address climate change require large purchases and a lot of planning (i.e. new heaters, new transportation habits, etc.), you can start composting to reduce your waste at home, right now, with a backyard or worm bin (also called vermiculture)! It’s easy to make dirt, not waste—and it matters. In fact, conservative calculations show that if an average Minnesota household composts all its food scraps in a backyard bin or worm bin, it saves 124 lbs. of CO2 emissions every year.