Climate change drives disaster risk
Climate change can increase disaster risk in a variety of ways - by altering the frequency and intensity of hazard events, affecting vulnerability to hazards, and changing exposure patterns.
Disaster risk is magnified by climate change; it can increase the hazard while at the same time decreasing the resilience of households and communities.
Climate change refers to a change in the climate that persists for decades or longer, arising from either natural causes or human activity. Climate change is already modifying the frequency and intensity of many weather-related hazards as well as steadily increasing the vulnerability and eroding the resilience of exposed populations that depend arable land, access to water, and stable mean temperatures and rainfall. Risk to weather-related hazards is concentrated in low and middle-income countries. Although the precise impact of climate change is not certain, and it is important to be aware that not all areas will be impacted in the same way, projected impacts of climate change that will drive disaster risk include:
- Droughts: The number of people suffering extreme droughts across the world could double in less than 80 years, which has major implications for the livelihoods of the rural poor, and can also lead to increased migration streams. There will likely be a large reduction in natural land water storage in two-thirds of the world, especially in the Southern Hemisphere.
- Sea level rise: Coastal flooding events could threaten assets worth up to 20 % of the global GDP by 2100. The population of coastal areas has grown faster than the overall increase in global population. Global “hotsports” for flooding are projected to be in north western Europe and Asia.
- Infectious diseases: By 2050, mosquitoes that carry vectore-borne diseases like Malaria could reach an estimated 500 million people. Global warming has led to a loss in biodiversity, resulting in increased transmission and incidence of disease. Due to altered climate patterns, urbanization and deforestation bats and rodents, which are responsible for 60 percent of the diseases transmitted from animals to humans, have flourished.
- Wildfires: By 2030, fire season could be three months longer in areas already exposed to wildfires. In Western Australia, for example, this would add up to three months of days with high wildfire potential.
- Cyclones: Even though the attribution of tropical cyclones to climate change is difficult, a robust increase of the most devastating storms with climate change is evident. Under 2.5°C of global warming, the most devastating storms are projected to occur up to twice as often as today.
Changes in the geographic distribution of weather-related hazards, which may lead to new patterns of risk. An example on changes in geographic distribution of hazards: How changes in weather patterns could lead to more insect invasions.
Risk associated with weather-related hazards is disproportionately concentrated in developing countries and within these countries in poorer sectors of the population. Poverty and constrained access to productive assets mean that rural livelihoods that depend on agriculture and other natural resources are vulnerable to even slight variations in weather and seasonality.
The impact of climate change in rural and urban areas is intimately linked. As the sustainability of rural livelihoods declines and disaster risk increases, it is possible that increased rural to urban migration may occur. Related to climate change, in rural areas more frequent and extreme droughts, as well as changes in mean temperature and precipitation levels will cause further stress to these already vulnerable livelihoods.
What is attribution science?
Attribution science is a field of climate science that investigates the links between climate change and extreme weather events. This new but rapidly growing field of research aims to estimate how human-induced climate change affects the magnitude and probability of an event. Attribution science cannot determine if climate change caused an event. But it can determine if climate change made some extreme events more severe and more likely to occur, and if so, by how much.
Opportunities for building resilience
- UNDRR, 2009b
It is important to differentiate between climate change and the disaster risks associated with climate change. However, as with all the underlying risk drivers, because climate change is so closely linked to a number of other risk drivers, it must be addressed in combination with reducing these other drivers of risk. If these drivers are not addressed, disaster risk will continue to increase even if climate change is successfully mitigated.
Patterns of risk that may be driven by climate change are also related to factors such as the growth of informal settlements in exposed areas, lack of investment in drainage infrastructure, and deficiencies in urban and local governance. By addressing these, we can build resilience to climate change.
Climate change has emerged as a sector in itself at the national, regional and international levels, with its own institutional arrangements, global framework, and funding mechanisms. Since the formulation of the Nairobi Work Programme at the Conference of the Parties in 2006, a plethora of strategies, frameworks and funding mechanisms has certainly created the impression of convergence and coherence of climate change agendas with those of disaster risk reduction and sustainable development.
Several countries, such as the Philippines, Vietnam and others in the Pacific region, have managed to take the opportunity to effectively merge regulation and technical guidelines as well as national policy frameworks and budgets for disaster risk reduction and climate change adaptation. However, those countries remain the minority, and most national policies, despite citing the respective other domain, maintain distinct boundaries in concepts, plans, methodologies, reporting lines, responsibilities, budgets, and other areas.
"Accurate field-scale maize yield measurements are important to guide farming practices, as well as helping direct investments and policies that can improve food security."
"Initiative to help the banking sector in Honduras identify and appraise opportunities for investment that can help build climate resilience at high-risk sectors."
"Recent floods in Southern China highlight the need to incorporate climate resilience into infrastructure and supply chains."