Heatwaves and flash floods: yes, this is Britain’s ‘new normal’


Hayley J. Fowler, Newcastle University

“It’s hard to believe, isn’t it, that we had a heatwave just last week?”

Those words were spoken by a BBC news presenter, in front of graphic images of fire service rescues, as heavy rain caused floods and landslides which closed many roads and railway lines. In recent days there have dramatic floods across the north of England, particularly around Manchester, the Peak District and Yorkshire.

For me, this is personal, as I am from the worst affected area. I went to high school where people spent the night in their Civic Hall. Three miles away from where I grew up, a dam holding back Toddbrook Reservoir has been at risk of collapse and the town of Whaley Bridge was evacuated. But I’m not surprised that we are seeing flash flooding and I expect it to get worse in the future.

I am a professor at Newcastle University, where I lead a large research group focused on understanding changes to intense rainfall events and flash floods. Over the past eight years we’ve been working closely with colleagues at the UK Met Office to develop new very high-resolution climate models that can simulate these very intense summer storms and therefore predict what might happen in a warming climate.

Our models tell us that by 2080 summers in the UK will be much hotter and drier. Heatwaves will be more common. In fact a report released by the Met Office on the same day as the latest flash floods tells us that heatwaves are already happening more often. When Cambridge recently hit 38.7℃, the UK became one of 12 countries to break its national temperature record this year.

The world is warming. But although UK average summer rainfall is predicted to decrease, our models tell us that when it does rain it will be more intense than has been the case. Flash flooding in the UK is generally caused by intense rainstorms, where more than 30mm falls in an hour. Climate models predict these will happen five times more often by 2080.

Part of the reason for this is the simple fact that warmer air can hold more moisture. But that’s too simple: the availability of moisture also increases in areas close to warm oceans – warmer sea surface temperatures cause more moisture to be evaporated into the atmosphere, providing additional fuel for these intense storms. And here’s the scary bit: the Atlantic Ocean provides a vast source of moisture for storms in the UK.

But that’s not the whole story. Heavy, short rain storms are intensifying more rapidly than would be expected with global warming (what we call the Clausius-Clapeyron relationship). Research also suggests that more intense storms can themselves grow bigger, and with both the intensity of the rainfall and the spatial footprint of the storm increasing, the total rainfall in an “event” could double.

What’s more, the larger storms seem to have an ability to draw in more moisture from the surrounding area and become even more intense: the additional energy (heating) fuelling the uplift of air within the storm’s core draws in even more moisture from the surface, allowing them to grow even larger, with more potential for flooding. These also provide the perfect ingredients for large hail storms.

So, it is entirely consistent that we might expect both more heatwaves and more intense summer thunderstorms in a warmer climate. We also know which areas of the country are already susceptible to these flash floods from our analysis of historical records of flooding. Newspapers have reported on the dramatic impacts of these floods for centuries and this has allowed my team to reconstruct a flash-flooding history of the UK.

Certain parts of the country are highly vulnerable as their rivers respond quickly to rainstorms. These rivers tend to be found in steep, upland catchments underlain by non-permeable rocks, mainly in the north and west of the UK. High-risk catchments also include urban areas where the ground is also non-permeable, for entirely different reasons.

Many of the towns reported to have suffered “biblical” flooding recently have suffered repeated flooding through history, but perhaps not within living memory. For example, Whaley Bridge is mentioned twice in the flood chronologies for events in June 1872 and July 1881:

On 19th [June 1872] the Goyt was 12 to 14 feet above its normal level. At Whaley Bridge houses near the river were completely flooded and people were taken into the chapel and inns … in Macclesfield a woman and child were drowned when the river Bollin overflowed. Two reservoirs burst in the vicinity.

This rich archive of knowledge, including the prevalence of flooding in certain towns, even specific roads, is something we should draw upon in planning both the emergency response to these flash floods and for reducing their future impact. We can learn a lot from the past in how to manage the greater risks of flooding the future will bring.The Conversation

Hayley J. Fowler, Professor of Climate Change Impacts, Newcastle University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The UK has a national climate change act – why don’t we?



It’s time Australian politicians were guided by national climate change legislation.
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Anna Skarbek, Monash University; Anna Malos, ClimateWorks Australia; Cameron Hepburn, University of Oxford, and Matthew Carl Ives, University of Oxford

No matter who wins the upcoming federal election, both the ALP and LNP are committed to remaining in the Paris Climate Agreement.

This means every five years Australia is expected to submit progressively stronger targets to reduce greenhouse gas emissions, and report on progress. And by 2020, Australia is expected to submit a long-term emissions reduction strategy showing how to get to net zero emissions.




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Regardless of what policy mix is chosen to achieve this, the process of hitting the Paris targets is now a permanent feature of economy-wide decision-making, one that will need credible ongoing support from government and businesses. Policy uncertainty, and a lack of national framework, has reduced investment confidence.

The UK has shown how national climate change legislation can guide institutional action, and not only dramatically cut emissions, but also promote economic growth.

Victoria rolled out similar legislation in 2017, one of the first pieces of legislation in the world to be modelled on the Paris Agreement.

But Australia lacks a national version of Victoria’s or UK’s legislation.

We have national targets, but not yet ongoing systems embedded in departments. These systems would include measures to ensure continuous target-setting every five years (as used in other jurisdictions) with guidelines and progress reporting obligations. A lack of national legislation means the community and businesses lack transparency about Australia’s long-term direction, pace and progress.

How national climate change legislation would work

A national Climate Change Act would reduce recognise climate change was not taken into account when many current laws were developed, and reduce policy instability around Australian meeting our Paris obligations by:

  • providing a role for governments and courts to flesh out and stabilise the low carbon transition

  • guiding an emissions reductions path that looks ten years ahead, across all sectors of the economy, and that can be ratcheted up if policies fail to meet their targets

  • ensuring transparent reporting of emissions and progress towards meeting interim Paris Agreement targets

  • allocating responsibilities across government for reporting and climate-conscious planning

  • signalling to business, communities and government agencies about emerging opportunities in a low carbon economy.

How Victoria did it

In 2017, the Victorian Labor government rolled out state-wide climate legislation, the Victorian Climate Change Act.

This legislation recognises how addressing climate change needs a whole-of-government approach, extending obligations to each state government portfolio.

And it has already catalysed climate change reporting and planning activity across government. An independent committee
has been tasked with advising on the first ten years of emissions budgets.

Government departments are preparing adaptation plans for each sector, reviewing operational guidelines and establishing regular reporting of emissions in sectors and their future plans.




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Australia’s major parties’ climate policies side-by-side


The UK’s success story

The UK passed its Climate Change Act in 2008 with a near unanimous vote. It has guided government decisions on national energy and industrial policy ever since.

The Act contains a process for setting economy-wide, multi-year targets, generating a clear, but flexible path towards its long-term objective – an 80% reduction in national greenhouse gas emissions by 2050. It’s not explicit about how targets are to be met and successive governments have been free to choose their own mitigation policies.

What has resulted is a clear shift away from the politics of the past where climate change action was traded off against other government goals.

Ever since the Act passed, subsequent UK parliaments have created management and efficiency initiatives, a minimum price on carbon (called carbon price floors), renewable energy targets, competitive reverse auction schemes and capacity markets.

The UK’s national climate change act has dramatically reduced their carbon emissions to below 1860s levels.
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Combined, these policies promote a competitive, sustainable, low carbon energy supply, along with economic growth and increased national energy security.

And the results have been extraordinary: emissions in the UK have fallen dramatically since 2008, with the UK’s carbon dioxide emissions now below 1860s levels.

National transparency would improve the market

With a clear legislative process with interim targets every five years, a Climate Change Act for Australia would provide businesses and the public with a certainty around the pace of climate change action that reaches beyond the political cycles.

Governments would still have the freedom to choose interim targets and how to deliver them, but the legislation would create transparency around our obligations.

It would also ensure that a transition to a low-carbon future does not risk financial stability.

Regulatory bodies, such as the Australian Prudential Regulation Authority, the Bank of England, and the Financial Stability Board, recognise the necessity for climate change legislation to create confidence in markets. They are already applying pressure to local and international financial markets to improve disclosure of climate risk.

Finally, national legislation would ensure the market and the public are kept up-to-date about progress and future pathways, and how they can be involved in the process along the way. This includes investing in Australia’s potential as a new lower-carbon powerhouse.




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Let’s agree what is agreed, and move on

Australian politicians don’t often agree on climate change action, but the major parties do agree on Australia staying in the Paris Agreement.

A national Climate Change Act for Australia would embody this commitment, aligning us with the international process in a policy-flexible framework. Agreement on such an Act would show the Australian public that each party is serious about tackling climate change, providing a stable platform for the next parliament.The Conversation

Anna Skarbek, CEO at ClimateWorks Australia, Monash University; Anna Malos, Project Manager, climate and energy policy, ClimateWorks Australia; Cameron Hepburn, Professor of Environmental Economics, University of Oxford, and Matthew Carl Ives, Senior Researcher in Economics, University of Oxford

This article is republished from The Conversation under a Creative Commons license. Read the original article.

UK becomes first country to declare a ‘climate emergency’



Days of protest by Extinction Rebellion have brought parts of London to a standstill.
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Chris Turney, UNSW

On Wednesday night a bipartisan UK Parliament passed an extraordinary measure: a national declaration of an Environment and Climate Emergency.

The UK is the first national government to declare such an emergency. The decision marks a renewed sense of urgency in tackling climate change, following a visit to Parliament by teenage activist Greta Thunberg , the broadcast of David Attenborough’s documentary Climate Change: The Facts and 11 days of protest by environmental group Extinction Rebellion that paralysed parts of London.




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There are now some 49 million people living under national, city and local declarations of a climate emergency around the world.

Extinction Rebellion protesters surround a boat blocking Oxford Circus, London.
Kevin J. Frost/Shutterstock

What is a climate emergency?

While there is no precise definition of what constitutes action to meet such an emergency, the move has been likened to putting the country on a “war footing”, with climate and the environment at the very centre of all government policy, rather than being on the fringe of political decisions.

The UK are legally committed to a 80% reduction in carbon emissions by 2050 (relative to their 1990 levels) and was recently recognised as one of just 18 developed economies that have driven down carbon dioxide emissions over the last decade.

Some city and local councils have set out their climate emergency policies to become carbon zero by 2030 built around renewable energy supplies, more energy-efficient housing and a host of other measures. Yesterday’s decision in Parliament implies further national reductions and investment in this space.




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Counting down to 2030

The year 2030 is an important target. In spite of what climate contrarians might voice very loudly, five of our planet’s warmest years on record have occurred since 2010, whilst 2018 experienced all manner of climate extremes that broke numerous global records.

It’s sobering to realise that, because the oceans are a major sink of heat, the estimated 40-year delay in the release of this energy back into the atmosphere means the conditions of the last decade are in part a consequence of our pollution from the 1970s.

With the planet to experience further warming from the heat held by the oceans, there is increasing international focus on meeting the United Nation’s Paris Agreement which was signed by 197 countries in 2016. This ground-breaking agreement has the ambitious global aim of preventing global temperatures from reaching 2˚C above pre-industrial levels (the late nineteenth century) by 2100, and ideally should be no more than 1.5˚C.

Declaring an emergency was one of the demands from the Extinction Rebellion protest put to the UK government.
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A report by the Intergovernmental Panel on Climate Change (the IPCC) has suggested that meeting this target means annual global carbon emissions must effectively halve between now and 2030, and then fall to zero by 2050. This is a target the UK opposition party Labour are now calling for.

More recent studies suggest even more ambitious cuts may be required.

The cost of inaction

Research in Australia has investigated the cost to the global economy if the Paris Agreement is not met and the world hits 4˚C warmer.

The values are eye-watering: an estimated US$23 trillion a year over the long-term. This has been likened to the world experiencing four to six global financial crises on the scale of 2008 every year.

In Australia, the cost would be on the order of A$159 billion a year, with most of the losses caused by drought-driven collapses in agricultural productivity and sea level rise. The expense to each Australian household has been put at the order of A$14,000.

The declaration of climate emergency by the UK comes at a crucial time in Australia, just two weeks out from a federal election. While the major parties have made public statements of support for the Paris Agreement, it remains unclear whether current and former leaders are fully aware of their obligations.




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At a time when politicians discuss the need to “live within our means” when it comes to national finances, this does not appear to translate to the environment when we’re considering future generations.

Instead we seem to be caught in a debate surrounding the costs of action rather than inaction. The next generation of Australian voters certainly don’t seem confident about political commitments to their future as they hold their third national school strike tomorrow.

The welcome announcement from the UK is a major step in the right direction and potentially a watershed moment for a more sustainable global future. Is it too much to hope Australia could follow next?The Conversation

Chris Turney, Professor of Earth Science and Climate Change, ARC Centre of Excellence for Australian Biodiversity and Heritage, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.