Climate Change and Land: An IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems
On August 7, 2019, the Intergovernmental Panel on Climate Change (IPCC) published Climate Change and Land, a special report that addresses greenhouse gas emissions and their link to desertification, land degradation and food security. The IPCC was set up by the United Nations Environment Programme and the World Meteorological Organization in 1988.
This report is the culmination of two years of work by 107 experts from 52 countries. The report will be a key scientific input at the Conference of the Parties of the UN Convention to Combat Desertification (COP14) in New Delhi in September 2019.
Global population growth and
changes in per capita consumption, the report notes, have caused “unprecedented
rates of land and freshwater use,” and climate
change has exacerbated this land degradation. The report projects a decrease in the stability
of food supply “as the magnitude and
frequency of extreme weather events that disrupt food chains increases.”
The report considers land-based measures that can help mitigate climate change, such as reforestation, afforestation, reduced deforestation, and the use of bioenergy crops. However, it says that these measures have certain limits, and the widespread use of bioenergy crops, for instance, could increase risks of desertification, land degradation, food security and sustainable development.Land must remain productive to maintain food security as the world’s population increases the report asserts. And it concludes that there must be rapid reductions in anthropogenic greenhouse gas (GHG) emissions across all sectors in order to reduce the negative impacts of climate change on land ecosystems and food systems.
About a quarter of the Earth’s ice-free land area is subject to ‘human-induced degradation’, that is, an adverse land condition caused directly or indirectly by humans that leads to a long-term reduction in, or loss of, the land’s biological productivity, ecological integrity, or value to humans.
Climate change, including an increase in the frequency and intensity of extreme climate events, has adversely impacted food security and terrestrial ecosystems, and contributed to desertification and land degradation in many regions. The report defines desertification as “land degradation in arid, semi-arid, and dry sub-humid areas resulting from many factors, including climatic variations and human activities.”
The expansion of areas under agriculture and forestry (including those for commercial production) have supported food availability for the world’s growing population. These changes (which vary vastly by region) have contributed globally to increasing GHG emissions, the loss of forests, savannahs, grasslands and wetlands, and declining biodiversity.
People currently use a quarter to a third of the land’s potential ‘net primary production’ (NPP) for food, feed, fibre, timber and energy. (NPP is the amount of carbon accumulated through photosynthesis minus the amount lost by plant respiration, which would prevail in the absence of land use.)
Changes in land conditions (such as heat-related events) and heavy precipitation events can significantly modify the likelihood, intensity and duration of many extreme climate events. They can also affect temperature and rainfall in regions hundreds of kilometres away.
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.
The report says that access to cleaner energy sources and technologies can help to mitigate climate change and combat desertification and forest degradation. This can have socioeconomic and health benefits, especially for women and children.
Insecure land tenure affects the ability of people to make changes to land that can help with climate change adaptation and mitigation. Land policies (including the recognition of customary tenure, community mapping, redistribution, decentralisation, co-management, and regulation of rental markets) can help provide people with security and give them flexibility in their responses to climate change.
Public health policies to improve nutrition (such as increasing the diversity of food in public procurement), health insurance, financial incentives, and awareness-raising campaigns can potentially influence food demand, reduce healthcare costs, and contribute to lower GHG emissions. Influencing the demand for food by promoting diets based on public health guidelines can enable more sustainable land management.
Agricultural practices based on indigenous and local knowledge can contribute to overcoming the challenges of climate change, food security, biodiversity conservation, desertification and land degradation. Such practices can be adopted through coordination between businesses, producers, consumers, land managers, policymakers and indigenous peoples.
The land and food sectors around the world face particular challenges of ‘institutional fragmentation’ and narrowly focussed policies. Coordination with other sectors, such as public health, transportation, environment, water, energy and infrastructure can benefit them all at the same time.
The report says that policies which reduce food loss and waste, influence dietary choices, improve access to markets, secure land tenure, and factor environmental costs into food, among others, could help make land use more sustainable. Such policies could also enhance food security, lower emissions, reduce land degradation, desertification and poverty as well as contribute to climate change adaptation and mitigation.Focus and Factoids by Oorna Raut.
Intergovernmental Panel on Climate Change (IPCC)
Intergovernmental Panel on Climate Change (IPCC), Geneva
07 Aug, 2019