Climate change is an increase in global average temperature caused by human activities – particularly the burning of fossil fuels that add heat-trapping greenhouse gases to Earth’s atmosphere. But people can adapt to climate hazards and take advantage of opportunities that come with changing weather conditions.
Communities around the world are getting better at doing this. They are building flood defenses, planting drought-resistant crops and protecting critical infrastructure from storm damage.
Water
Clean, safe water is essential for life. Yet around 450 million people lack access to adequate water supplies, and this number is growing as climate change makes floods and droughts more frequent. Floods contaminate and damage sanitation systems, which can increase the spread of deadly pathogens such as cholera; severe droughts reduce food production, increasing hunger and malnutrition; and rising sea levels increase salinity in drinking water sources. Droughts and floods also reduce agricultural productivity and increase costs of water-intensive industries such as tourism and energy.
In addition, increased temperatures are expected to cause more water to fall than the soil and vegetation can absorb, resulting in floods or excess runoff. This water can pick up pollutants like fertilizer and carry them into larger bodies of water, contaminating drinking water supplies. It can also degrade water quality by raising water temperatures and causing the growth of Harmful Algal Blooms.
As a result, water is one of the most critical climate adaptation priorities. But many of the tools available to address climate change-related water impacts – such as insurance, managed retreat via home structural mitigations and beach nourishment, or evacuation – have yet to be implemented in sufficient scale, nor are they accessible to all communities at risk.
Adaptation strategies for water must be integrated into broader development, climate action and resilience efforts. They can be broadly classified as nature-based or technology-driven, and must include both. Nature-based mitigation strategies such as restoring and maintaining healthy ecosystems act as carbon sinks and help reduce greenhouse gas emissions, while technological approaches such as improved drainage and water storage can provide protection against climate hazards and promote sustainable development.
IUCN has been active in the area of water and climate, with an emphasis on implementing the IUCN Global Water Programme, which provides a platform for sharing experiences. The programme focuses on improving water management in a changing climate and supporting the achievement of the Sustainable Development Goals, including the targets on climate change. However, in order to make a difference, global dialogue must transition into implementation and country-driven actions.
Heat
As extreme heat blankets the world, claiming lives and disrupting food production, water supplies, and more, people are learning how to adapt. But unlike hurricanes, wildfires and floods, adaptation to blazing temperatures is more complex and expensive. From opening cooling centers and extending public pool hours to girding electric grids for peak air-conditioning demand, climate adaptation to heat takes many forms.
Communities need to become more resilient, from the ground up. The Paris Climate Agreement aims to increase resilience in all sectors of society, including education, water, and housing. This work is happening on a large scale, from building flood defenses to designing new schools that are more heat-tolerant. In urban areas, this may include improving street design and reducing the “urban heat island” effect – where streets, buildings, and pavement amplify the intensity of heat waves.
While reducing heat-trapping emissions can help reduce the severity of climate change, it is important to prepare for the impacts that are inevitable. This is why the 2015 Paris Agreement includes, for the first time, an adaptation goal.
Scientists predict that global warming will lead to more extreme weather and disasters, particularly in rural and low-income countries. Developing nations and communities that experience the most severe climate hazards also have the least resources to cope, which means they will face additional risks to their livelihoods, health, and wellbeing.
This is why climate adaptation must go hand in hand with mitigation – cutting back on greenhouse gas emissions to limit the extent of future warming. The world is currently on track to warm even more than the target agreed in Paris, which could be catastrophic for communities around the globe.
The good news is that we have the tools to mitigate the impacts of climate change and adapt to those that cannot be avoided. But we need to move faster if we want to avoid the most devastating effects of warming. The upcoming climate talks at COP26 in Glasgow offer an opportunity to raise ambitions on both mitigation and adaptation. It will be crucial that developed nations make a concrete commitment to support developing nations’ ability to adapt to unavoidable climate impacts, including heat.
Food
Climate change affects all aspects of our lives, from homes to health and food. The goal of adaptation is to reduce the risks of these climate impacts by learning how to cope with them. That means preparing for floods, heat waves, wildfires, and drought, while taking advantage of potential benefits like longer growing seasons and increased yields in some regions.
Many of the same actions we take to mitigate climate change – such as cutting greenhouse gas emissions and expanding carbon “sinks” – can also help us adapt. But adaptation involves a different set of steps, and it’s crucial to make sure we have a plan in place.
One of the most important ways to adapt is through our diets. Changing our habits can have a profound impact on the world’s climate, even if we do everything else right.
For example, eating less meat and more plant-based foods will help reduce the amount of water used to grow crops. And reducing the waste we produce will cut down on emissions, too. About 1 billion tons of food – or 17 percent of the world’s food supply – ends up in trash bins each year. That adds up to a huge amount of greenhouse gases.
Eighty percent of the world’s crops are rainfed, and climate change is altering rainfall patterns, increasing droughts, and making extreme weather more common. This is putting food security at risk for millions of people, especially in the world’s poorest regions.
Rising temperatures also speed up evaporation from soil and plants, leading to reduced irrigation and water shortages. That may lead to more flooding and crop failures – as well as more pathogens and pollutants that can make their way into our food supplies.
To combat these impacts, countries are implementing a range of adaptation strategies. Find out how your country is adapting by looking up its National Adaptation Plan. And see how communities are using nature to protect themselves from climate threats – like restoring mangrove forests in Kiribati that serve as a barrier against sea-level rise and provide fish, shelter, and water for humans and wildlife alike.
Energy
The climate changes caused by our greenhouse gas emissions are already putting pressure on energy systems. These include the power plants that provide electricity, as well as natural gas and oil pipelines and refineries. Increasing temperatures and rising sea levels will affect the reliability of those systems, increasing the risk of outages. They are also affecting the availability of water, which is critical for energy production. As the climate warms, melting polar ice and shifting rain patterns can reduce freshwater supplies. That’s especially important for energy-adjacent activities such as farming, cooling, and transportation.
Fortunately, we can slow the pace of climate change. We can also invest in technologies that will help make our energy infrastructure more resilient to future challenges. That’s why it’s so important to support the clean energy transition, including renewable and storage technologies. It will benefit our businesses, our communities and the environment.
Climate actions can significantly reduce the cost of a range of climate impacts, from hurricane damages to power system costs and residential utility bills that increase as the climate changes. In fact, one study found that if we don’t rein in our climate-related losses, those costs could reach the level of GDP by 2025 and more than double to GDP by 2100.
In our current policy scenario, the additional energy needed to adapt to climate change adds up to about 5000 GtCO2eq by the end of the century. In more stringent mitigation scenarios that keep global mean temperature below 2.5°C and even lower in those that are well below, the total energy use for adaptation is much smaller.
The difference is mainly due to variation in the cost of generation. Developing and tropical regions with low electricity efficiency and slower energy transitions will experience higher energy needs for climate change adaptation. The impact is also amplified by the direct effect of increased thermal comfort humidity on peak electricity demand, which can amplify power system costs and contribute to heat stress on equipment. Those effects are partly offset by behavioral changes in heating and cooling appliances, the use of more efficient new buildings and business models and a reduction in energy consumption from better urban planning.