Nearly 80% of cities to undergo dramatic and potentially disastrous changes, study finds
London will have a similar climate in three decades’ time to that of Barcelona today, according to research – but if that seems enticing, a warning: the change could be accompanied by severe drought.
Madrid will feel like present-day Marrakech by 2050, and Stockholm like Budapest, according to a report on the likely impacts of the climate crisis. Around the world, cities that are currently in temperate or cold zones in the northern hemisphere will resemble cities more than 600 miles (1,000km) closer to the equator, with damaging effects on health and infrastructure.
Among other analogues, the study suggests Moscow will resemble Sofia, Seattle will feel like San Francisco and New York will be comparable to Virginia Beach. The researchers have created an interactive map showing hundreds of cities and their 2050 counterparts.
Water shortages will affect scores of cities now in temperate climates as a result of the global heating, which is forecast to be by as much as 3.5C in European cities in summer and 4.7C in winter.
But what about at the other icy end of the planet?
Antarctica is an icy giant compared to its northern counterpart. The water frozen in the Greenland ice sheet is equivalent to around 7 metres of potential sea level rise. In the Antarctic ice sheet there are around 58 metres of sea-level rise currently locked away.
Like Greenland, the Antarctic ice sheet is losing ice and contributing to unabated global sea level rise. But there are worrying signs Antarctica is changing faster than expected and in places previously thought to be protected from rapid change.
The threat from beneath
On the Antarctic Peninsula – the most northerly part of the Antarctic continent – air temperatures over the past century have risen faster than any other place in the Southern Hemisphere. Summer melting already happens on the Antarctic Peninsula between 25 and 80 days each year. The number of melt days will rise by at least 50% when global warming hits the soon-to-be-reached 1.5℃ limit set out in the Paris Agreement, with some predictions pointing to as much as a 150% increase in melt days.
But the main threat to the Antarctic ice sheet doesn’t come from above. What threatens to truly transform this vast icy continent lies beneath, where warming ocean waters (and the vast heat carrying capacity of seawater) have the potential to melt ice at an unprecedented rate.
Almost all (around 93%) of the extra heat human activities have caused to accumulate on Earth since the Industrial Revolution lies within the ocean. And a large majority of this has been taken into the depths of the Southern Ocean. It is thought that this effect could delay the start of significant warming over much of Antarctica for a century or more.
However, the Antarctic ice sheet has a weak underbelly. In some places the ice sheet sits on ground that is below sea level. This puts the ice sheet in direct contact with warm ocean waters that are very effective at melting ice and destabilising the ice sheet.
Scientists have long been worried about the potential weakness of ice in West Antarctica because of its deep interface with the ocean. This concern was flagged in the first report of the Intergovernmental Panel on Climate Change (IPCC) way back in 1990, although it was also thought that substantial ice loss from Antarctica wouldn’t be seen this century. Since 1992 satellites have been monitoring the status of the Antarctic ice sheet and we now know that not only is ice loss already underway, it is also vanishing at an accelerating rate.
The latest estimates indicate that 25% of the West Antarctic ice sheet is now unstable, and that Antarctic ice loss has increased five-fold over the past 25 years. These are remarkable numbers, bearing in mind that more than 4 metres of global sea-level rise are locked up in the West Antarctic alone.
Thwaites Glacier in West Antarctica is currently the focus of a major US-UK research program as there is still a lot we don’t understand about how quickly ice will be lost here in the future. For example, gradual lifting of the bedrock as it responds to the lighter weight of ice (known as rebounding) could reduce contact between the ice sheet and warm ocean water and help to stabilise runaway ice loss.
On the other hand, melt water from the ice sheets is changing the structure and circulation of the Southern Ocean in a way that could bring even warmer water into contact with the base of the ice sheet, further amplifying ice loss.
There are other parts of the Antarctic ice sheet that haven’t had this same intensive research, but which appear to now be stirring. The Totten Glacier, close to Australia’s Casey station, is one area unexpectedly losing ice. There is a very pressing need to understand the vulnerabilities here and in other remote parts of the East Antarctic coast.
The other type of ice
Sea ice forms and floats on the surface of the polar oceans. The decline of Arctic sea ice over the past 40 years is one of the most visible climate change impacts on Earth. But recent years have shown us that the behaviour of Antarctic sea ice is stranger and potentially more volatile.
But in 2015, the amount of sea ice around Antarctica began to drop precipitously. In just 3 years Antarctica lost the same amount of sea ice the Arctic lost in 30.
So far in 2019, sea ice around Antarctica is tracking near or below the lowest levels on record from 40 years of satellite monitoring. In the long-term this trend is expected to continue, but such a dramatic drop over only a few years was not anticipated.
There is still a lot to learn about how quickly Antarctica will respond to climate change. But there are very clear signs that the icy giant is awakening and – via global sea level rise – coming to pay us all a visit.
Nerilie Abram, ARC Future Fellow, Research School of Earth Sciences; Chief Investigator for the ARC Centre of Excellence for Climate Extremes, Australian National University; Matthew England, Australian Research Council Laureate Fellow; Deputy Director of the Climate Change Research Centre (CCRC); Chief Investigator in the ARC Centre of Excellence in Climate System Science, UNSW, and Matt King, Professor, Surveying & Spatial Sciences, School of Technology, Environments and Design, University of Tasmania
Climate crisis disasters are happening at the rate of one a week,
though most draw little international attention and work is urgently
needed to prepare developing countries for the profound impacts, the UN
has warned.
Catastrophes such as cyclones Idai and Kenneth in Mozambique and the drought afflicting India
make headlines around the world. But large numbers of “lower impact
events” that are causing death, displacement and suffering are occurring
much faster than predicted, said Mami Mizutori, the UN
secretary-general’s special representative on disaster risk reduction.
“This is not about the future, this is about today.”
This means that adapting to the climate crisis could no longer be seen as a long-term problem, but one that needed investment now, she said. “People need to talk more about adaptation and resilience.”
A short series of statements that recognises the current urgency and absolute primacy of the climate crisis. May be revised or corrected. Undecided how this series will go. Away njoio over the weekend (no not Glastonbury).
Let’s get this clear from the outset: I represent nobody except myself. Despite supporting Jeremy Corbyn’s UK Labour party I have never been a member of the Labour party. I may have briefly been a member of SERA (Socialist, Environment and Resources Association) approximately 40 years ago while I was an active anti-nuclear activist. SERA was and continues to be closely associated with the Labour party.
I have been publishing inconsistently on the internet since 1998 or 1999 and I am certainly amoung the earliest bloggers. I have a portfolio of posts and articles that establishes me a competent and accomplished blogger, journalist or political activist – whatever I am. I warned of climate crisis online – from memory – in 1999.
Politicians encounter problems addressing the climate crisis because of 1. the short-termism inherent in contemporary politics and 2. the huge influence of climate crisis deniers on them.
Politicians are typically elected for terms of four or five years. They are concerned with one or at most two terms only by which time they will have lost power to the opposition.
I have difficulties comprehending climate change deniers. Perhaps I understand it in the ignoramus US resident Donald Trump.
Climate crisis activist protocol says stay positive, promote the notion that climate crisis can be averted. I am breaking with that protocol. I believe that the tipping point has been passed, that climate change has now acquired it’s own frightening dynamic. Apologies for saying this to those of you who have children.
10/7/19 There’s an issue with normally intelligent people having minds closed to the state we’re in. I’m talking in terms of the world having been destroyed, having passed tipping points that develop their own frightening dynamic. Their minds are closed and they cannot contemplate the state we’re in.
