With the United Nations Climate Change Conference starting earlier this week (28th November 2011) in Durban, South Africa, which aims to advance efforts towards a global agreement to cut carbon emissions, I thought it would be fitting to write an article on the impacts of climate change to bring to life why conferences such as these are so important.
Following on from Gareth’s article “A Succinct Guide to Climate Change” [1], this article aims to outline a range of climate change impacts. For information on what climate change is, the causes of climate change, the uncertainty, and how we can stop it, please refer to Gareth’s article. However, if you are interested in the alarming impacts that climate change is having then please read on.
By now we are all aware of the impacts that climate change is having on our climate. Instead, this article will assess how climate change has an impact on: food security, water security, biodiversity and ecosystem services, and human security.
Food Security
Climate change has led to significant environmental degradation, including loss of biodiversity and land, and water degradation. Despite this, total global food production has continually grown since the 1960s because of agricultural adaptation. However, the benefits have been uneven and one billion people still go hungry. To make matters worse, food prices are now on the rise and are extremely volatile [2].
Food prices are on the rise because of the increased demand for food, while there is also an increase in poor harvests due to variable weather (due to climate change) and an increase in the use of biofuels, which are grown on valuable agricultural land.
The demand for food will double within the next 25-50 years, primarily in developing countries, and the type and nutritional quality of food in demand will change (increased meat demand). The challenge will be to sustain growth in the agricultural sector to feed the world, while biofuels take over agricultural land and climate change degrades what land is left [2].
To be able to produce enough food for the world, agriculture must continue to adapt by:
- Addressing water deficit problems e.g. through improved drought tolerant crops and irrigation technologies.
- Improving the temperature tolerance of crops.
- Combating new or emerging agricultural pests or diseases.
- Addressing soil fertility, salinisation of soils and improving nutrient cycling.
- Reducing energy-intensive inputs.
- Reducing greenhouse gas emissions while maintaining productivity.
- Improving the nutritional quality of food.
- Reducing post-harvest losses.
- Improving food safety.
Water Security
Human-induced climate change is projected to decrease water quality and availability in many arid and semi-arid regions, and increase the threats posed by floods and droughts in most parts of the world [3].
A summary of the global water crisis:
- Water scarcity is growing – by 2025 more than half of the world’s population is projected to live under conditions of severe water stress.
- Water quality is declining in many parts of the world.
- Many of the major “food-bowls” of the world are projected to become significantly drier.
- 70% of all freshwater is used for irrigation and 15-35% of irrigation withdrawals exceed supply rates and are therefore unsustainable.
- 50-60% of wetlands have been lost globally.
Biodiversity and Ecosystem Services
Changes in climate have affected biodiversity already, and will continue to do so in the future.
Climate change will continue to have an impact on:
- The timing of reproduction or migration events.
- The length of the growing season.
- Species distributions and population sizes.
- The frequency of pest and disease outbreaks.
- The incidence of coral bleaching and mortality (through increasing water temperature, sea level and acidification).
The figure below shows that the main drivers of biodiversity loss are growing [4].
Climate change is projected to affect all aspects of biodiversity:
- Directly – through increases in temperature, changes in precipitation (and in the case of marine systems changes in sea level etc.)
- Indirectly – through climate changing the intensity and frequency of disturbances, such as wildfires.
The risk of extinction will increase for many species, especially those that are already at risk due to factors such as low population numbers, restricted or patchy habitats, and limited climatic ranges.
Ecosystems that may be most threatened by climate change include coral reefs, mangroves and other coastal wetlands, remnant ecosystems, ecosystems with restricted distribution, and high latitude/high altitude ecosystems.
Human Security
Climate change is also increasing the risk of conflict because of the following:
- Environmentally-induced migration: Tens of millions of people living in low lying deltaic areas or Small Island States will be displaced by increases in sea level and will be forced to migrate.
- Climate-induced decline in food production: Food shortages are likely to occur where there is already hunger and famine today.
- Climate-induced degradation of freshwater resources: Water shortages are likely to occur in areas where there are already water shortages.
- Climate-induced increase in storm and flood disasters: Increased incidence of severe weather events.
- In addition: Natural resources are being depleted with loss of ecological goods and services, and there is an increased incidence of disease.
The result: Climate change will cause an increased risk in local and regional conflict and migration, depending on the social, economic and political circumstances.
Security risks associated with climate change: the figure below highlights the regions which could develop into crisis hotspots [5].
Summary
The effects of climate change are having a severe impact on food security, water security, biodiversity and ecosystem services, and human security.
We must address climate change to prevent the following:
- Adverse impacts on food security: Decreased agricultural productivity and adverse impacts on fisheries.
- Adverse effects on water security: Decreased water availability and water quality, and increased risk of floods and droughts.
- Loss of key ecosystem services: Adverse effects on ecological systems and increased loss of biodiversity.
- Adverse effects on human health: Increased incidence of diseases and extreme weather events.
- Adverse effects on human settlements: Increased flooding, coastal erosion and sea level rise, and an increase in forced migration and risk of conflict.
It is imperative that the United Nations Climate Change Conference has a positive outcome in terms of a global agreement to cut carbon emissions, in order to try and reduce the impacts discussed in this report. On an individual level, there are actions you can take. Using our energy survey can help you discover your energy usage and consequently try and reduce it, or how about purchasing more sustainable products across a wide range of categories?
References
For more information on the United Nations Climate Change Conference, please refer to:
http://unfccc.int/meetings/durban_nov_2011/meeting/6245.php
[1] “A Succinct Guide to Climate Change” http://www.energysavingwarehouse.co.uk/news/54/20/A-Succinct-Guide-to-Climate-Change.html
[2] FAO: The state of food insecurity in the world 2011 http://www.fao.org/publications/sofi/en/
[3] IPCC: Climate change and water http://www.ipcc.ch/pdf/technical-papers/climate-change-water-en.pdf
[4] Millennium Ecosystem Assessment (Synthesis) http://www.maweb.org/documents/document.356.aspx.pdf
[5] German Advisory Council on Global Change: Climate change as a security risk http://www.wbgu.de/fileadmin/templates/dateien/veroeffentlichungen/hauptgutachten/jg2007/wbgu_jg2007_kurz_engl.pdf
