IPCC scientist David King says the world has changed faster than generally predicted in the fifth assessment report from the UN’s Intergovernmental Panel on Climate Change (IPCC) in 2014.

He referred especially to the loss of land ice and sea ice, and to the weather extremes in which he said warming probably played a role.

Several other scientists contacted by the BBC supported his emotive language.

The physicist Prof Jo Haigh from Imperial College London said: “David King is right to be scared – I’m scared too.”

“We do the analysis, we think what’s going to happen, then publish in a very scientific way.

“Then we have a human response to that… and it is scary.”

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Petteri Taalas, the secretary-general of the World Meteorological Organization (WMO), a specialised UN agency, said he fully supported United Nations climate goals, but he criticised radical green campaigners for forecasting the end of the world.

It’s the latest chapter in the long debate over how to communicate climate science to the public.

Will emotive language leave young people depressed?

Dr Taalas agrees polar ice is melting faster than expected, but he’s concerned that public fear could lead to paralysis – and also to mental health problems amongst the young.

“We are fully behind climate science and fully behind the (upcoming) New York climate summit”, he said.

“But I want to stick to the facts, which are quite convincing and dramatic enough. We should avoid interpreting them too much.

“When I was young we were afraid of nuclear war. We seriously thought it’s better not to have children.

“I’m feeling the same sentiment among young people at the moment. So we have to be a bit careful with our communication style.”

He said most of the changes were within the IPCC forecast range – although some – like polar ice – were at the top end of the range.

The polar scientist Andrew Shepherd, from Leeds University, agreed with that assessment.

Others noted the models hadn’t been sufficiently sophisticated to foresee events like this year’s extreme European heatwave or the slow-moving Hurricane Dorian – described by NASA as “extraordinary” and “a nightmare scenario”.

Others mentioned severe ice melting at the poles; Tasmania suffering record droughts and floods in consecutive years; record wildfires in the Arctic and an unprecedented two large cyclones in Mozambique in one year.

Changes ‘anticipated for decades’

Gerald Meehl, a senior scientist at the US National Center for Atmospheric Research (NCAR) in Boulder, Colorado, told us he’d been anticipating changes like these for four decades, although he hadn’t been certain when they would arrive.

“I have a sense of the numbing inevitability of it all,” he said.

Few of the scientists we contacted had faith that governments would do what was needed to rescue the climate in time. They’re alarmed that global warming of just over 1C so far has already created a new normal in which historic temperature records will inevitably be broken more often. This is the predictable side of climate change.

Prof King argues that some changes were not well forecast.

What is the science behind extreme weather events?

The loss of land ice in Antarctica, for instance, is at the upper range of predictions in the IPCC AR5. And there are record ice losses in Greenland

Then there’s this year’s French heatwave.

Dr Friederike Otto from Oxford University is an expert in the attribution of extreme events to climate change.

She told us that in a pre-climate change world, a heatwave like this might strike once in 1,000 years. In a post-warming world, the heatwave was a one-in-a-100 year phenomenon. In other words, natural variability is amplifying human-induced climate heating.

“With European heatwaves, we have realised that climate change is a total game-changer,” she said. “It has increased the likelihood (of events) by orders of magnitude.”

Researchers had not yet had time to investigate the links between all of the major extreme weather events and climate change, she said.

With some phenomena such as droughts and floods there was no clear evidence yet of any involvement from climate change.

And it was impossible to be sure that the slow progress of Dorian was caused by climate change.

‘We can’t wait for scientific certainty’

Prof King said the world could not wait for scientific certainty on events like Hurricane Dorian. “Scientists like to be certain,” he said.

“But these events are all about probabilities. What is the likelihood that (Dorian) is a climate change event? I’m going to say ‘very high’.

“I can’t say that with 100% certainty, but what I can say is that the energy from the hurricane comes from the warm ocean and if that ocean gets warmer we must expect more energy in hurricanes.”

He continued: “If you got in a plane with a one in 100 chance of crashing you would be appropriately scared.

“But we are experimenting with the climate in a way that throws up probabilities of very severe consequences of much more than that.”

Should the UK bring climate targets earlier?

Pierre Friedlingstein from Exeter University said he’d been surprised by the onslaught of extreme weather. He said he expected extremes to happen as forecast by the IPCC – but had not expected them so quickly.

Prof King said the situation was so grave that the UK should bring forward its date for cutting emissions of greenhouse gases to almost zero from 2050 to 2040.

Prof John Church from the University of New South Wales in Sydney, Australia told us: “Some things appear to be happening faster than projected. This may be partially related to the interaction of climate change and natural variability as well as the uncertainty in our understanding and projections.

“In my own area of sea level change, things are happening near the upper end of the projections.

“What is scary is our lack of appropriate response. Our continued lack of action is committing the world to major and essentially irreversible change.”

Lib Dems set out radical agenda for tackling climate emergency

Exclusive: Citizens’ assemblies and a Green Investment Bank among key planks of election bid. Fiona Harvey Environment correspondent Sat 14 Sep 2019 

Citizens’ assemblies will decide what action should be taken on the climate crisis, the Treasury’s ability to stymie green measures will be neutralised and the Green Investment Bank will be revived under proposals set to be key planks of the Liberal Democrats’ general election bid.

Along with sweeping reform of Whitehall, including bringing back a department of climate change, local government would be given new powers to cut emissions, there would be a moratorium on airport expansion and an end to fracking, and the UK would achieve net-zero carbon status by 2045 – five years sooner than the current government goal.

“Moving to net-zero is a complete game-changer,” Wera Hobhouse, the Lib Dem spokesperson for the environment and climate change, told the Guardian. “The whole of government and society need to understand the need to get to net-zero – everything we do needs to be seen in terms of that target.”

Under the proposals to be presented to the Lib Dem conference in Bournemouth this weekend, a new minister, who will attend cabinet, would be appointed chief secretary to the Treasury and oversee policy across departments to ensure it meets the zero-carbon pledge.

“The biggest hurdle [to climate policies] was always the Treasury,” said Hobhouse. Soon after Theresa May unveiled her zero-carbon target this summer, her chancellor, Philip Hammond, claimed it would cost too much. “Having a chief secretary to keep reminding the chancellor of the need to get to net-zero is key,” said Hobhouse.

To gain public support for urgent action on emissions, the Lib Dems would convene citizens’ assemblies across the country to debate new measures. These would include ways to ensure a massive expansion of electric vehicles and better public transport, and how to encourage new technology such as heating homes with hydrogen instead of gas. Councils would also be given greater powers over planning, for instance to promote electric vehicles, cycling and walking.

“Citizens’ assemblies would not replace politicians’ decision-making, but would inform the options,” said Hobhouse. “We need decisive action – the government is not doing anything, they are dithering.”

The Green Investment Bank, created under the coalition government, was sold off under George Osborne. Under a Lib Dem government, a replacement would be set up with public money, and have the powers to borrow money from the private sector.

Hobhouse said Brexit was getting in the way of tackling the climate emergency: “Brexit means having less money, and it is very counterproductive. We need international cooperation – climate change is a global problem.”

The Lib Dems would end the sale of diesel and petrol cars by 2030 – 10 years sooner than the Conservatives – and stop fracking. There would also be more support for onshore wind and solar, which Hobhouse said the Conservatives had “stopped in their tracks” by drastically changing incentive schemes and planning laws.

Green campaigning groups, keen that the climate crisis should not be overshadowed by Brexit as a general election looms, welcomed the Lib Dems’ focus. “Our country may be divided over Brexit, but it is not divided over the need for action on the nature and climate emergency – polling is consistently showing that concern over climate is at an all-time high and a large majority support urgent action,” said Gareth Redmond-King, head of climate change at WWF-UK.

“Now we need the climate and nature crisis prioritised at the highest level of government, and billions in new funding, to deliver on the rhetoric. We must stop things like airport expansion that make meeting net-zero even more difficult.”

Jenny Bates, a campaigner at Friends of the Earth, said: “With the government’s net-zero target currently lacking anywhere near enough policy to back it up, we’d like to see all parties thinking about what they’d do to make sure the target is actually reached. It’s no good talking about a net-zero future while pursuing a programme of roadbuilding, airport expansion and fracking.”