What are the consequences and implications?
There are a number of consequences to consider from the current and projected changes in climate. On a global scale, climate change will affect many of the key determinants of wealth and wellbeing, including water supply, food production, human health, availability of land, economic stability, infrastructure, and the environment. The Stern Commission on Climate Change reported that ‘...if we don’t act, the overall costs and risks of climate change will be equivalent to losing at least 5% of global GDP (gross domestic product) each year, now and forever. If a wider range of risks and impacts is taken into account, the estimates of damage could rise to 20% of GDP or more. In contrast, the costs of action – reducing greenhouse gas emissions to avoid the worst impacts of climate change – can be limited to around 1% of global GDP each year’ [see reference 18] (for further information on the costs and economic impact of climate change please see the HM Treasury Stern Review on the economics of climate change).
As climate change accelerates, it will manifest differently across the globe. The effects of climate change are expected to be most severe in developing countries, but there will also be implications for developed countries, including the UK. In all countries, generally it will be the poorest people who will be most affected. People who are on lower incomes tend to live in higher risk areas in substandard housing and are often unable to cope with the physical and economic strains presented by climate change. [see reference 19] The Environment Agency found that in the UK, the most deprived 10 per cent of the population were eight times more likely to be living in the coastal floodplain than the least deprived 10 per cent. [see reference 20]
Developing countries:
Climate change presents a real threat to the developing world especially as many developing countries are already facing problems coping with challenges posed by their existing climate. Geographic exposure, low incomes, high burden of disease, and a greater reliance on climate sensitive sectors such as agriculture mean that developing countries are especially vulnerable. [see reference 21]
Climate change contributes, and will contribute, to obstructing poverty reduction and economic growth of developing countries. Climate change is likely to impact on countries’ abilities (particularly developing countries) to achieve sustainable development pathways, as set out by the Millennium Development Goals (MDG) framework. [f] [see reference 22] These countries may not have the resources to cope with climate change, with agricultural incomes and health in particular being under threat. In Africa, for example, it is expected that the environment needed for sustainable agriculture and yield potential (particularly in arid areas) will decrease. [see reference 23] This could result in further problems over food security and intensify levels of malnutrition.
Climate change has the potential to lead to mass migration and conflict, especially when this is coupled with the rapid population growth predicted in the developing world over the next few decades. [see reference 21] Conflicts over increasingly scarce natural resources (already witnessed in disputes over land and water in Sudan [see reference 24]) are also likely to become more frequent – the United Nations (UN) Security Council now has on its agenda the implications of climate change for international security. [see reference 25]
Developed countries:
Developed countries may not be affected by climate change to the same degree as developing countries because:
- their economies generally rely less on sectors such as agriculture than developing countries
- they tend to be located in cooler, higher latitudes [g]
- they have more money and better resources for adaptation. [see reference 26]
A major effect of climate change for developed countries will be on wealth and the economy. Economic output could be affected in different ways. While developed countries will be able to cope to some degree through adaptation, this process itself will also add to expenditure. [see reference 19] Extreme weather events could also have serious repercussions for trade and global financial markets. This could result from disruptions to communications and more unstable costs of insurance and capital. [see reference 19]
For a summary of the potential impacts of climate change on various sectors please see table SPM.1 in the IPCC, 2007: Summary for Policymakers. In: Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. [see reference 28]
In the UK:
Climate change is expected to have potential consequences for a number of key sectors in the UK. This can be through global impacts affecting the UK (ie crop failures overseas leading to food insecurity and possibly food shortages) or through direct impacts within the UK. [see reference 29] Examples of sectors that may be affected include:
- Economy, industry and infrastructure
The costs of extreme weather events, such as storms, floods, droughts, and heatwaves, will increase rapidly at higher temperatures. Flooding events and the number of people at risk from flooding are expected to rise in the UK. There is a risk in the UK of infrastructure damage from flooding and storms, especially in coastal regions. [see reference 19] A study by the UK Government’s Foresight Programme estimated that a rise in global temperatures of 3 to 4°C could result in an increase in the average annual costs of flood damage to homes, businesses and infrastructure in the UK from around 0.1 per cent of GDP to 0.2 – 0.4 per cent of GDP. [see reference 30] The study also suggested that the number of people at high risk from coastal or river floods would increase from 1.6 million today to between 2.3 and 3.6 million by 2080. [see reference 30] Increased temperatures during summer months may also affect productivity in urban areas as office buildings could become difficult to work without additional air-conditioning. [see reference 19] In already-dry regions (eg South East England), hot summers will further increase soil drying and subsidence damage to properties that are not properly underpinned. [see reference 19] - Agriculture
An initial increase in agricultural productivity may occur in the UK due to longer growing seasons and the carbon fertilisation effect; but this will depend on adequate water and requires changing crops and sowing time. [see reference 19] As temperature rises become more severe, productivity could be more negatively affected, as during the 2003 heat wave, when a number of European countries, including the UK, witnessed a sharp decline in crop yields. [see reference 31] - Water
The water industry is directly responsible for approximately 4 million tonnes of CO2 emissions annually. [see reference 32] Water UK comments that climate change will ‘impact every aspect of water services, from infrastructure to operations to demand on finances. Reservoirs will be impacted in terms not just of quantity, but operation, quality and structure. Assets on the coast and in flood plains – in other words, most of them – will be at more risk from floods, storm damage, coastal erosion and rises in sea level. Existing sewerage systems were not designed to cope with climate change. Rainfall will be more intense and likely to overwhelm parts of the network and cause local flooding.' [see reference 32] Limitations of water availability as summer run off declines could also be of concern, especially in the South East where population density is on the rise. Droughts could also occur more regularly. [see reference 19] - Ecosystems
Natural ecosystems in the UK could be negatively affected by an increase in temperatures and alterations to precipitation patterns. [see reference 33] The effective working of the marine ecosystem is dependent on changes to both ocean climate and acidification. ‘Marine air and sea surface temperatures (SST) have been rising at a similar rate to land air temperature, but with strong regional variations; 2006 was the second-warmest year in UK coastal waters since records began in 1870. Warmer winters have been strongly linked to reduced breeding success and survival in some seabird populations.’ [see reference 34]
[g] It is important to note that while this may be the case, the degree and rate of climate changes (such as temperature and precipitation) may be greater at high latitudes.