In recent months we’ve seen the launch of the Intergovernmental Panel on Climate Change (IPCC) report on the latest physical climate science (Working Group 1) and the UK-hosted COP26 conference in Glasgow. In the UK, the Government has also published their latest Climate Change Risk Assessment, CCRA3. Over the coming months we’ll see the release of new IPCC reports on impacts, adaptation and vulnerability (Working Group 2) and on mitigation of climate change (Working Group 3). It is therefore timely to consider why we need adaptation and how this relates to mitigation, or reducing emissions, to help reach and go beyond a net zero goal.
Climate change impacts
Mitigation and adaptation are the key tools available to us in order to avoid the worst climate impacts on people, infrastructure and nature. However, ideally we need to make changes in ways that enhance other development goals including reducing poverty and inequality, promoting good governance and improving wellbeing.
We have observed climate change on every continent, with attribution studies finding a human fingerprint in many key aspects including temperature, rainfall, drought and sea-level rise. There is also increasing evidence of the impacts these changes in climate hazards have already caused, with some parts of the world much more vulnerable to the hazard than others.
Looking into the future, our climate model projections provide ranges of how future climate hazards might evolve in time, with the amount of climate change being strongly driven by the magnitude of future greenhouse gas emissions and the sensitivity of the climate system to the higher levels of atmospheric greenhouse gas concentrations. Whilst the challenges from climate change present themselves at a local level, they are present across the globe and the atmosphere doesn’t take into account where emissions come from – all sources of greenhouse gas emissions contribute to warming and climate disruption.
Why not just reduce emissions?
Returning to the original aim – to avoid climate impacts in a way that is sensitive to the other stresses and pressures on people and nature – reducing, or mitigating, emissions seems like the ideal solution. Mitigation of emissions also has benefits beyond avoiding climate impacts, such as improved energy security and better air quality.
However, whilst mitigation can avoid some of the impacts, even in the most ambitious emission reduction scenarios we are committed to at least some further global warming beyond present day levels. Even if global emissions are reduced to net zero over the next few decades, uncertainty in the climate response means we may actually still experience considerable levels of global warming.
Adaptation options are almost always implemented locally, providing direct benefits to local populations, as well as indirect benefits to those connected to or dependant on a region. Many adaptation actions, particularly the introduction of physical protection measures, can often be implemented relatively quickly. For instance, the time to construct the massive Thames Barrier in London was less than a decade. Carefully designed adaptations can also deliver additional benefits beyond avoiding climate impacts, including more hospitable and liveable urban environments.
So why not just adapt? The answer to this is multi-dimensional. Adapting to lower levels of climate change is more manageable and affordable than for higher levels of change, so mitigation makes adaptation easier. Indeed, costs of adaptation can grow exponentially with higher levels of warming, so without significant mitigation, adaptation may not be affordable. Even if we put the cost issues aside, there are limits to adaptation in most practical situations. For instance, there is only so high you can or might want to build a sea wall. Furthermore, adaptation doesn’t solve problems such as ocean acidification, which is associated with the increase in atmospheric carbon dioxide, nor is it an option for many species and ecosystems threatened by a rapidly changing climate.
For those who favour adaptation in place of mitigation, the IPCC Working Group 1 report reminded us that net zero emissions are needed to stabilise warming at any level. If we kept greenhouse emissions constant at today’s levels, we would not halt climate change, leading to even greater environmental consequences and reducing the options for adaptation.
To deal with the challenges of climate change there is a case for both strong mitigation and adaptation, planned and delivered as part of a combined strategy. That strategy needs to take into account other development aims, and the differing capacity of different peoples, organisations and nations to respond. It also needs to be strongly evidence-based. These climate resilient pathways or scenarios provide our roadmap to the future.
A partnership approach
At the Met Office we work with partners to play an important role in the transition to a resilient net zero future. Weather advice provides early warning of events hours, days and even a few weeks ahead, and has become vital to protecting lives and keeping businesses running. Our seasonal outlooks provide information further out and are opening new opportunities for longer term tactical planning, for instance in the transport and energy sectors. Climate projection information, such as UKCP18 – the latest UK Climate Projections – is helping people understand the risks over coming decades and increasingly enabling them to make plans for local adaptation.
In considering and developing our services to inform adaptation and mitigation we need to maintain a degree of humility and openness, recognising that valuable knowledge to inform solutions comes from the people facing the local challenges and who will have to live with the responses. We are increasingly learning how to co-develop adaptation and mitigation approaches, but have many lessons to learn, especially from recent projects in the developing world. Furthermore, even the best weather and climate information is only part of the solution, and we need to get better at combining this data with that from other disciplines to produce innovative ways forward for a resilient low carbon future.
We have been sharing information on adaptation on our social media channels this month. Follow #GetClimateReady to learn more and look out for a focus on mitigation soon.
 Adaptation refers to reducing either vulnerability or exposure to climate change. The UNFCCC describes it as “adjustments in ecological, social, or economic systems in response to actual or expected climatic stimuli and their effects or impacts. It refers to changes in processes, practices, and structures to moderate potential damages or to benefit from opportunities associated with climate change.” See https://unfccc.int/topics/adaptation-and-resilience/the-big-picture/what-do-adaptation-to-climate-change-and-climate-resilience-mean