IPCC report on the effects of climate change: A look at the key findings

Humans directly use more than 70 per cent of the Earth's ice-free land surface for food, feed, fibre, timber and energy.
Humans directly use more than 70 per cent of the Earth's ice-free land surface for food, feed, fibre, timber and energy.PHOTO: AFP

The UN Intergovernmental Panel on Climate Change’s special report on land use that was released on Thursday (Aug 8) points to an urgent need to reform the way food is grown. Here’s a look at some of the key findings:

URGENT PROBLEM

- Humans directly use more than 70 per cent of the Earth's ice-free land surface for food, feed, fibre, timber and energy. The land and ecosystems such as forests play a vital role in regulating the climate and watersheds essential for mankind. The land is both a source and a sink for greenhouse gas emissions but booming demand for food means it is a major source of planet-warming emissions.

- Data since 1961 show that rapid population growth and changing diets have caused unprecedented rates of land and water use - agriculture accounts for about 70 per cent of global fresh water use. Rapid agricultural expansion has led to widespread destruction of forests, wetlands, grasslands and other ecosystems and increased land degradation and desertification, leading to widespread soil erosion.

- About a quarter of the Earth's ice-free land area is subject to human-induced degradation. For example, soil erosion from agricultural fields is estimated to be 10 to more than 100 times higher than the natural rate of soil formation.

- This has made the land more vulnerable to further erosion and greater extremes of heat, drought and floods caused by climate change. This in turn will affect yields and food security for millions more people in the coming decades.

- The IPCC says there is an urgent need to reform the way food is grown to drastically reduce farming's environmental footprint, boost efficiency and to cut food waste to ensure there's enough food for all in the future.

MOST VULNERABLE

- Asia and Africa are projected to have the highest number of people vulnerable to increased desertification. North America, South America, the Mediterranean, southern Africa and central Asia may be increasingly affected by wildfire. The tropics and subtropics are projected to be most vulnerable to crop yield decline.

- Since pre-industrial times, the land surface air temperature has risen nearly twice as much as the global average temperature, intensifying heatwaves, reducing rainfall, especially in dryland areas, and increasing water evaporation rates.

Already, about 821 million people, many of them in poorer dryland areas, are undernourished.

EMISSIONS AND FOOD WASTE

- Agriculture, forestry and other land uses are responsible for about 23 per cent of mankind's greenhouse gas emissions during the period 2007-2016. Add in emissions associated with all parts of agriculture, forestry and other land uses, such as transport, grain drying and manufacturing of farm inputs such as fertiliser and the percentage is even higher.

 
 
 
 

- Data available since 1961 shows the per-capita-supply of vegetable oils and meat has more than doubled and the supply of food calories per capita has increased by about one third. Currently, 25-30 per cent of total food produced is lost or wasted, leading to higher greenhouse gas emissions.

SOLUTIONS

- Steps including sustainable food production, improved forest management, ecosystem conservation and land restoration, reduced deforestation and cutting food waste can all help farmers and societies adapt and improve food security.

- Preserving and restoring wetlands, mangroves and peatlands can also lock away large amounts of carbon dioxide and can offer quick benefits.

- Other steps include improving access to markets, securing land tenure for farmers, factoring environmental costs into food, empowering women and indigenous peoples and better public health policies to improve nutrition, such as increasing the diversity of food sources.

- However, while land can mitigate climate change by soaking up CO2, there are limits to the use of land-based solutions, such as bioenergy crops or afforestation. Widespread use at the scale of several million square kilometres globally for such crops and forests could increase risks for desertification, land degradation and food security.

Source: IPCC