For more than 50 years, the Earth’s climate has been changing due to increasing greenhouse gas (GHG) emissions from the burning of fossil fuels such as coal and oil, as well as deforestation and other human activities. The warming of the Earth’s atmosphere and waters, loss of land and sea ice, and rising global sea levels are not new phenomena. However, these global changes have been occurring at increasing rates in the last 30 years, particularly in the last decade. Science shows that climate change will continue, and accelerate, in the years ahead, with significant impacts on the health of all our global ecosystems including oceans, forests, freshwater, and even human and urban ecosystems and the resources they contain.
While substantially reducing GHG emissions is essential to avoiding the worst impacts of climate change, mitigation alone is not enough. Even with emission reductions, some warming will still occur. Adaptation planning at the local, State, and national levels can limit the damage caused by climate change, as well as the long-term costs of responding to climate-related impacts that are expected to grow in number and intensity in the decades to come.
Read more about adaptation planning and its importance in the effort to curb global warming below.
- If GHG emissions continue unabated, Alaska and the Arctic region as a whole, warming projections of 4–11ºC are at least double the mean increase for the world. And the Arctic region is already experiencing an array of impacts including severe winter storm surges and flooding, infrastructure damage and loss, land erosion, species loss, and the displacement of people and communities.
- A number of scientists expect to see overall increases in precipitation in some parts of the world, including increases in the intensity of hurricanes and more intense heavy rainfalls.
- Projected impacts also indicate a decline in snowpack, earlier snow and ice melt, and more land areas affected by drought and wildfires.
- Sea-level rises resulting in potentially significant losses of coastal wetlands.
- All of these impacts will affect food and water supplies, natural resources, ecosystems, human life and property.
- Carbon dioxide (CO2) and other GHGs can remain in the atmosphere for decades or centuries after they are produced. This means that today’s emissions will affect the climate for years to come, just as the warming we are experiencing now is the result of emissions produced in the past.
- Because of this time lag, the Earth is committed to some additional warming no matter what happens now to reduce emissions. With worldwide emissions continuing to rise, adaptation efforts are necessary to reduce both the cost and severity of both mitigation and climate change impacts for decades to come.
- Current projections have underestimated the actual rates of climatic changes and impacts. For instance, sea-level rises have occurred 50% faster than the projected rate, and the area of summer Arctic sea ice has decreased at three times the projected rate.
- Acting now to limit the potential damage from climate change is often smarter—and costs less in the long run—than acting later. “Proactive adaption” requires assessing the vulnerability of natural and manmade systems, as well as the costs and benefits of action versus inaction, and planning alternatives accordingly. From the methods for building or repairing bridges, dams, and other infrastructure, to the rules and regulations governing coastal development and wetland protection, the decision whether to consider climate change now will have implications down the line.
- Recognise that adaptation must happen at local and regional levels. Climate changes and their associated impacts vary greatly from location to location. Although national and international action is essential, many important decisions about how best to manage systems affected by climate change are made at local and regional levels.
- Adaptation planning requires an understanding of those systems that are most and risk—and why. That means finding answers to questions in three key areas:
- Exposure: What types of climate changes and impacts can we expect, and which systems will be exposed? What is the possible range of severity of exposure, including the duration, frequency, and magnitude of changes in average climate and extremes?
- Sensitivity: To what extent is the system (or systems) likely to be affected as a result of projected climate change? For instance, will the impacts be irreversible (such as death, species extinction or ecosystem loss)? What other substantial impacts can be expected (such as extensive property damage or food or water shortages)?
- Adaptive Capacity: To what extent can the system adapt to possible scenarios of climate change and/or cope with projected impacts? What is feasible in terms of repair, relocation, or restoration of the system? Can the system be made less vulnerable or more resilient?
- Successful adaptation planning relies on input from, and the alignment of, all key stakeholders. Because the impacts of climate change span entire regions, adaptation planning should involve representatives from Federal, State, and local government; science and academia; the private sector; and local communities.
- For vulnerable systems, prioritising adaptive measures based on the nature of the projected or observed impacts is vital. A list of criteria to aid in identifying key vulnerabilities include:
- Magnitude: Impacts of large scale (higher number of people or species affected) and/or high-intensity (catastrophic degree of damage caused such as loss of life, loss of biodiversity).
- Timing: Impacts are expected in the short term and/or are unavoidable in the long term if not addressed. Consider also those impacts with variable and unpredictable timing.
- Persistence/Reversibility: Impacts resulting in persistent damage (e.g., near permanent water shortage) or irreversible damage (e.g., disintegration of major ice sheets, species extinction).
- Likelihood/Certainty: Projected impacts or outcomes are likely, with a high degree of confidence (e.g., damage or harm that is clearly caused by rising temperatures or sea-levels). The higher the likelihood, the more urgent the need for adaptation.
- Importance: Systems at risk are of great importance or value to society, such as a city or a major cultural or natural resource.
- Equity: The poor and vulnerable will likely be hurt the most by climate change, and are the least likely to be able to adapt. Pay special attention to those systems that lack the capacity and resources to adapt.
Due to uncertainties in projected climate changes and in how systems will respond to those changes, adaptation options must be chosen based on a careful assessment of efficacy, risks and costs.