For the first month of the winter floods this year, it seemed like climate change was the elephant in the room, ignored by most politicians and most of the media debating the crisis that was steadily growing.

Rightly, the priority was on helping people whose homes and businesses were flooded. On the ground, emergency services and Environment Agency staff responded magnificently, working with local people and councils to keep communities safe, assist those at risk and help put lives back together after widespread disruption.

But it would be reckless not to grasp the opportunity to learn as many lessons as possible from the winter floods: about our nation’s lack of resilience to extreme weather, and its limited emergency response capacity; about land management and adaptation; and about the need to cut carbon emissions radically to secure a less volatile climate for our children and grandchildren.

As the rain continued into February and the flooding worsened, politicians finally started to do more than put their wellies on and pose for pictures in Somerset. Climate change was suddenly back on the political agenda at Westminster. The defence secretary said that climate change was “clearly a factor” in the period of stormy weather the UK had been experiencing. Labour leader Ed Miliband said that global climate change is an issue of national security for Britain. And during a heated session of prime minister’s questions, David Cameron said: “I believe man-made climate change is one of the most serious threats that this country and this world face.”

Any credible approach to addressing the threat to the UK from climate change requires both adaptation and mitigation. Suggestions that we can simply adapt to the impacts of climate change don’t stack up when you look at the seriousness of impacts at 2°C – let alone 4° or 6°, which we could see during the lifetimes of today’s young people.

Challenged to tell the truth about climate change, David Cameron claimed that the coalition had a programme to reduce carbon emissions right across the economy.

Alongside a much more integrated and urgent approach to adaptation, an economy-wide programme to radically reduce carbon emissions is exactly what we need. But it’s sadly not true to say that we have one in place. Nor it is enough to support a target to decarbonise the power system by 2030.

Cross-party talks have been proposed. These represent a wise and welcome step back from the rush to the dangerous politicisation of the climate change debate that has occurred in Australia and the United States – and that we have been seeing over recent years in the UK. So what should a credible approach to flood protection and climate change include?

Investment in flood protection

An obvious imperative is investment in flood protection. “Money is no object,” the prime minister declared earlier this year. Yet despite the limited increase in spending on flood defences, funding from the Department for Environment, Food and Rural Affairs (Defra) will still be £1.4 billion behind what the Environment Agency says it needs between 2015 and 2021 just to stop flood risk becoming even greater.

In addition to adequate spending on flood protection, ministers must reverse the cuts to the Environment Agency budget and the decision to slash to just six the number of people in the Environment Department working on adaptation. And they also need to factor in projections for the future cost of extreme weather.

Because the present approach is ignoring this, the Committee on Climate Change warned that current spending plans would result in the exposure of around 250,000 more households to significant risk of flooding by 2035. That, clearly, is completely unacceptable.

Flood resilience has to be properly planned and funded. As the Fire Brigades’ Union has highlighted, that includes flood emergency intervention, and the government should look again at the merits of a duty on the fire and rescue service in England and Wales to respond to major flooding – as happens in Scotland.

A radical rethink of land management

Adapting to climate change and building our resilience to flooding is about much more than hard flood defences. We need a radical rethink of land management to take proper account of climate change and reduce the threat to people’s homes and livelihoods, and to our food security.

Crucially, there must be a fundamental shift towards seeking to work with, rather than against, Nature. Not only would such an approach benefit wildlife and Nature, but it is also the best way to reduce our vulnerability to flooding and extreme weather events and increase our resilience.

Yet Defra has confirmed that the conditions farmers must meet to get public subsidies do not cover flood risk. The government needs to stop this irresponsible use of public money by ensuring that flood prevention is a non-negotiable condition of all farm subsidies.

Approaches to land management that help store more water in the uplands in places like peat bogs rather than in places like people’s living rooms are often good for improving water quality too, and have the potential to cut water bills for customers downstream.

Carbon reduction targets in line with science and equity

Climate-proofing our infrastructure and flood protection plans will be undermined, if not rendered impossible, unless we start taking urgent action to cut carbon emissions at a radically greater scale and pace than at present.

It shouldn’t be too much to ask that all parties commit to carbon reduction targets in line with science and equity. That means ruling out any weakening of the UK’s fourth carbon budget, as the Treasury has proposed. Why can the chancellor not grasp the employment benefits of leading the global transition to a zero-carbon economy – let alone the economic and social harm of a failure to avoid dangerous climate change?

We need UK ministers to be pushing for far greater EU ambition on carbon-emission reduction targets – 60% cuts by 2030 at the very least, 80% if we are to take risk and equity seriously – as well as for binding targets for efficiency and renewables to get us there. Right now the UK is not doing that. Instead, it opts for a ‘technology neutral’ approach as a shoe-in for new nuclear power, despite analysis that this will mean fewer jobs for the UK and despite serious safety concerns about nuclear energy and the absence of any safe, reliable solution for dealing with radioactive waste.

Energy saving should be the top priority for anyone concerned about high energy bills and the scandal of fuel poverty in the UK. We need a national retrofit to make all homes zero carbon – and zero bill – by 2030. Rather than weakening carbon-pricing measures, which would send completely the wrong signal to investors, the government should be recycling carbon tax revenues into a national programme to make all homes super energy-efficient and thus fuel-poverty-proof.

And finally, we need to confront the truth about unburnable carbon. We know that 80% of existing fossil fuels can’t and shouldn’t be burnt if we are to keep global temperature rises to below 2°C. We’ve had 0.8° of global warming so far, and given the human impacts of extreme weather in the UK – but, moreover, elsewhere – even 2° does not look like a ‘safe’ limit.

Right now, UK government ministers are spending a lot of time and money working out how to get even more unconventional sources of oil and gas out of the ground so that we can burn them. They need to spend their time working out how to keep the vast majority of existing fossil fuels in the ground instead.

Crucially, that means ditching the tax breaks and subsidies to fossil fuel companies and the fracking industry and getting behind our thriving home-grown renewable energy industry.

The UK is spending £12 billion every year on energy subsidies, the vast majority of which goes to the fossil fuel industry, directly or indirectly. Subsidies for renewable energy are a fraction in comparison.

Instead of ditching vital foreign aid, like the Daily Mail petition suggests, why not cut the billions spent on the UK’s fossil fuel subsidies and use the money for the relief of flood victims? Thousands of people signed a petition on this, initiated by Platform and delivered to the prime minister in February this year. The government needs to take note.

It makes no sense at all to use public money to drive climate destruction, yet that is exactly what these subsidies and tax breaks are doing, revealing the pernicious influence of the fossil fuel industry over politics. This must also be addressed.

Politicians often talk solemnly about the importance of long-term decisions for our future and that of our children. Their response to climate change is the best test of whether they mean it.

And we can’t sit back and wait. The years of inaction on climate change demonstrate that, more than ever, it’s dangerous to leave politics to politicians.

Last year, the politics of climate change from inside the Westminster bubble were bleak, but on the outside they were truly inspiring.

In Lancashire and Sussex, in the Arctic Ocean and all across North America, people have been getting together to send a very strong signal to their governments that the exploitation of unconventional fossil fuels – whether shale gas, tar sands or Arctic oil – is not compatible with a safe climate.

At the end of 2013, a new report from the RSA subtitled Facing Up to Stealth Denial and Winding Down on Fossil Fuels hit the nail on the head for the challenge we face. The touchstone, it argues, for any given intervention on climate change must quickly become not, “Will this reduce localised emissions?” but rather, “Will this help to keep coal, gas and oil in the ground?” With the general election fast approaching, this is a test we could apply to the policies put forward by politicians. And it will be up to civil society, in the UK and elsewhere, to hold decision makers to account, to force them to act in the public interest rather than in the financial interests of big oil and gas. From what I see there is a groundswell of citizens standing up to be counted – and it really will make all the difference.

Caroline Lucas is the MP for Brighton Pavilion and is former Leader of the Green Party of England and Wales.