Plant-Based Diets Can Combat Climate Change, Report Finds

A new report by the Intergovernmental Panel on Climate Change (IPPC) high­lights bet­ter global land man­age­ment and a move towards plant-based diets as effec­tive ways to com­bat cli­mate change.

The IPPC’s in-depth study, ​“Climate Change and Land,” was pre­pared by an inter­na­tional team of 107 experts from 52 coun­tries and explores how land use con­tributes to cli­mate change while also exam­in­ing the effects of cli­mate change on land and food secu­rity. This was the first and most com­pre­hen­sive study of the global land-cli­mate sys­tem. The IPPC is the United Nations body charged with assess­ing sci­ence related to cli­mate change.

The main mes­sage of the com­pre­hen­sive report is that in order to reduce green­house gases in a sig­nif­i­cant way and keep cli­mate change in check, changes are needed in global land use, agri­cul­ture and dietary habits.

It describes land as a crit­i­cal resource that must remain pro­duc­tive to ensure food secu­rity. When agri­cul­tural land loses its pro­duc­tiv­ity, this results in soil degra­da­tion, ero­sion, and even­tu­ally deser­ti­fi­ca­tion. Such land can­not absorb car­bon and con­tributes to cli­mate change while hav­ing a neg­a­tive effect on food secu­rity.

“Land plays an impor­tant role in the cli­mate sys­tem,” said Jim Skea, one of the report’s authors and co-chair of the IPCC’s Working Group III, which exam­ines the mit­i­ga­tion of cli­mate change. ​“Agriculture, forestry and other types of land use account for 23 per­cent of human green­house gas emis­sions. At the same time nat­ural land processes absorb car­bon diox­ide equiv­a­lent to almost a third of car­bon diox­ide emis­sions from fos­sil fuels and indus­try.”

The threat of soil degra­da­tion and ero­sion can be addressed through sus­tain­able land man­age­ment. Some of the mea­sures sug­gested in the study include the cul­ti­va­tion of green manure crops and cover crops, crop residue reten­tion, reduced or zero tillage and improved graz­ing prac­tices to pre­serve ground cover. Meanwhile other sus­tain­able agri­cul­tural prac­tices deemed to be ben­e­fi­cial to the preser­va­tion of land, include agroe­col­ogy and agro­forestry, con­ser­va­tion agri­cul­ture, crop diver­sity, crop rota­tion, organic farm­ing, the preser­va­tion of pol­li­na­tors, and rain­wa­ter har­vest­ing.

“The choices we make about sus­tain­able land man­age­ment can help reduce and in some cases reverse these adverse impacts,” said Kiyoto Tanabe, one of the experts and co-chair of the IPCC task force on national green­house gas inven­to­ries. ​“In a future with more inten­sive rain­fall the risk of soil ero­sion on crop­lands increases, and sus­tain­able land man­age­ment is a way to pro­tect com­mu­ni­ties from the detri­men­tal impacts of this soil ero­sion and land­slides. However there are lim­its to what can be done, so in other cases degra­da­tion might be irre­versible.”

“There is real poten­tial here through more sus­tain­able land use, reduc­ing over-con­sump­tion and waste of food, elim­i­nat­ing the clear­ing and burn­ing of forests, pre­vent­ing over-har­vest­ing of fuel­wood, and reduc­ing green­house gas emis­sions, thus help­ing to address land-related cli­mate change issues,” added Panmao Zhai, co-chair of IPCC Working Group I, which looks at the phys­i­cal sci­ence of cli­mate change.

But bet­ter land man­age­ment is not the only solu­tion to tack­ling cli­mate change and mit­i­gat­ing its effects. The IPCC experts sug­gest that a reduc­tion in resource-heavy meat con­sump­tion and an increased uptake of plant-based diets could free up land and reduce CO2 emis­sions by up to eight bil­lion met­ric tons per year by 2050.

Debra Roberts, co-chair of the IPCC Working Group II, charged with assess­ing the vul­ner­a­bil­ity of socio-eco­nomic and nat­ural sys­tems to cli­mate change, con­firmed that diet has a sig­nif­i­cant effect on cli­mate change

“Some dietary choices require more land and water, and cause more emis­sions of heat-trap­ping gases than oth­ers,” she said. ​“Balanced diets fea­tur­ing plant-based foods, such as coarse grains, legumes, fruits and veg­eta­bles, and ani­mal-sourced food pro­duced sus­tain­ably in low green­house gas emis­sion sys­tems, present major oppor­tu­ni­ties for adap­ta­tion to and lim­it­ing cli­mate change.”

The study’s experts also point out that bet­ter land man­age­ment prac­tices com­bined with a move towards plant-based diets and a reduc­tion in food waste do not only have the poten­tial to mit­i­gate cli­mate change but also result in pos­i­tive socio-eco­nomic effects. These changes can erad­i­cate poverty and hunger while improv­ing pub­lic health and the avail­abil­ity of clean water.

This lat­est IPCC report was approved in Geneva on August 7 at the IPCC’s 50^th ses­sion and pre­sented at a press con­fer­ence the next day at the World Meteorological Organization (WMO).

The report will pro­vide sci­en­tific inputs into nego­ti­a­tions at upcom­ing cli­mate con­fer­ences, includ­ing the Conference of the Parties of the U.N. Convention to Combat Desertification (COP14) to be held in New Delhi, India in September and the U.N. Framework Convention on Climate Change Conference (COP25) sched­uled for December in Santiago, Chile.

• Intergovernmental Panel on Climate Change