The world’s nations are gathered in Paris to agree a new treaty that will hopefully slow global warming.
So we asked some climate scientists, "What, if anything, makes you hopeful about climate change?" This is what they told us.
Jennie Mallela, research fellow, Australian National University
"Humanity is often at its best when responding to natural disasters. We show intelligence, compassion, and generosity when helping others. Unfortunately, it often takes a disaster to highlight these exceptional attributes. We do not excel at taking the precautionary approach which would prevent these disasters happening in the first place.
"I am hopeful that we will take the humane approach to dealing with the legions of displaced global citizens that will need help due to climate-induced natural disasters such as flooding, water, and food scarcity."
Michael Mann, professor of meteorology, Penn State University
"Last year, we saw renewables for the first time outcompeting fossil fuels in added electricity-generation capacity. For the first time in decades we saw global economic growth without any growth in carbon emissions. If we are going to avoid truly dangerous and irreversible changes in our climate, however, we need to accelerate the progress already underway, putting our foot to the metal when it comes to the transition away from a fossil fuel economy. I'm hopeful that we'll make significant progress toward that goal at the Paris climate summit later this year.
"I would like to see an international treaty that holds all nations to binding reductions in carbon emissions, building on the voluntary commitments and bilateral agreements (e.g. between China and the US) that are already in place."
Helen McGregor, fellow, University of Wollongong
"I have great hope in people: the critical mass of people concerned about climate change and their willingness to take action; the groundswell of people speaking up, from all sectors of the community, demanding that our political leaders be leaders on climate change; that people can see the consequences of climate change, and want to avoid the worst, for the vulnerable, for future generations, for people they don't even know.
"All this gives me hope."
Joanna Haigh, co-director of the Grantham Institute for Climate Change, Imperial College London
"I'm hopeful that there'll be a shift in mindset, across the population, that induces governments to understand the need to focus on developing renewable energy technologies."
Katrin Meissner, assistant professor of climate change, University of New South Wales
"My hope is that climate change will finally bring humans together. We will have to pull in the same direction – all together – regardless of our religion, cultural background, or skin colour. Unless we all take radical action now, these differences will pale in comparison to this catastrophic threat."
Mat Collins, joint Met Office chair in climate change, University of Exeter
"Science has shown us that climate change is a real issue for the planet and society. We don't yet know everything and there are still uncertainties, particularly on the regional impacts of climate change, but there is enough scientific information for action. My hope is that the Paris talks will produce some plans for serious action based on what is robustly known about the science of climate change."
Pramod Aggarwal, regional South Asia program leader, CGIAR Research Program on Climate Change, Agriculture and Food Security
"I am hopeful about how we will deal with climate change because we are moving from pointing out problems to identifying solutions. In agriculture, these solutions revolve around the availability of water and energy. Fortunately, a number of technological solutions such as water harvesting, solar pumps, conservation agriculture, and stress-tolerant seeds are available that can meet growing food demands in developing countries, despite increasing climatic risks.
"This, however, requires huge investments in infrastructure, institutions, governance, and policies. I am hopeful that richer sections of society will assist vulnerable farmers in realising these solutions for a secure and peaceful future for all."
Sally Brown, research fellow, University of Southampton
"Climate change is almost always seen as a threat, but it's also an opportunity, whether to change our environmentally bad habits or to be more responsible for the resources we use. I'm hopeful for greater awareness in adapting our environment to cope with adverse change, so that resources and infrastructure that supports societies is used or developed more responsibly, equitably and ethically, particularly in the poorest parts of the world, today and in the future."
Jonathan Bamber, professor in physical geography, University of Bristol
"As a species we're pretty resourceful and inventive. We've done some really amazing things in our short time on the planet: some good, some not so good. I think that through a combination of technological breakthrough and rational consensus about the importance and urgency of the problem, we will find creative and ingenious solutions. It will be a stony path, but I am optimistic we can navigate it."
Ilan Kelman, reader in risk, resilience, and global health, University College London
"I gain hope from the inspiring work dealing with climate change in communities from the Arctic to tropical islands. I have learned so much about tackling an immense challenge, about innovation and creativity, and about communicating the needed action to others. Unfortunately, no community can solve the problem alone and getting many others on board is proving to be difficult. But we at least know that we could address climate change if we choose to do so."
Richard Betts, chair in climate impacts, University of Exeter
"I'm hopeful because I now see more in-depth, grown-up conversation happening about climate change, with a much wider and more informed range of voices than a few years ago. Vocal minorities with superficial views still exist at both ends of debate, but thankfully they are increasingly irrelevant – pretty much everybody now accepts that humans are exerting an influence on climate, and the disagreement has moved to how much of a risk this poses.
"Some people are somehow confident that climate changes poses no appreciable risk. Personally I cannot see how they can be so confident, given that we know we are causing change but don't fully understand how this change will play out. But to me, a conversation on "how much risk is acceptable?" is a much more useful (and interesting) conversation than just shouting at each other from polarised, entrenched positions."
Alice Bows-Larkin, professor at the Tyndall Centre for Climate Change Research, University of Manchester
"I'm most hopeful about the creativity and open minds within the younger generation worldwide – and not just within the education system. Tackling climate challenge requires innovative thinking, bravery, and stepping outside of our comfort zone. People across all job types and within civil society must think in new ways, and do it quickly. Many of those in established positions feel too constrained to make a step change and do things differently, but that's what is needed. Often younger people are more able to ditch the ego and put the climate first – this is refreshing and necessary!
"I'd like to contribute by clearly laying out how great the challenge we face is, but also that there are different ways of thinking that are not about 'going backwards', but about creatively embracing our collective future."
Ailie Gallant, lecturer and research fellow, Monash University
"I'm hopeful because we are well-informed about the situation and we have the capacity, means, and innovation to do something about it. All that's needed is a collective will to take action."