Revealed: The cities that have been hit with 'climate whiplash' - as scientists describe the bizarre pattern as 'global WEIRDING'

Many of the world's largest cities are experiencing 'climate whiplash', a new report has revealed. 

This bizarre weather phenomenon sees regions flip-flop between severe droughts and flooding. 

Scientists have dubbed this bizarre pattern 'global weirding'. 

And worryingly, they say it could lead to an increasing number of climate disasters.

According to the report, by Water Aid, the cities experiencing the most severe climate whiplash are Hangzhou in China, Jakarta in Indonesia, and Dallas in the USA. 

These cities have experienced years of back-to-back floods and droughts, making it much harder for them to predict, and prepare for the next climate disaster. 

Co-lead scientist, Professor Katerina Michaelides, from the University of Bristol, says: 'Places that were historically wet are becoming dry and vice versa.

'Other places are now increasingly battered by both extreme floods and droughts.'

The Water Aid report compares rainfall and evaporation data for the 100 most populated cities in the world, plus 12 cities in which the charity works, over the last 44 years.

This dataset reveals that climate change is not affecting every city in the same way.

Professor Michaelides says: 'The findings from our study illustrate just how differently and dramatically climate change is expressing around the globe – there is no one-size-fits-all.'

However, 17 cities experienced an increase in both extremely dry and extremely wet periods and were defined as undergoing 'climate whiplash'.

Although these are spread across Asia, the Middle East, Africa, and North America, Asian cities are disproportionately affected by this trend.

Of the 17 whiplash cities identified in the report, nine were in Asia.

The danger of climate whiplash is that years of alternating drought and flood don't give cities the chance to properly prepare or recover from successive crises.  

WaterAid argues that 90 per cent of all climate disasters are currently caused by either too much or too little water.

Over the last 50 years, the charity warns that flooding and drought have become four times as common, with climate whiplash making regions even more exposed.

This year, the Dallas area experienced record-breaking rainfalls which triggered widespread flooding including a flash flood in February that left drivers stranded in high water.  

However, the city has also experienced deeper and longer droughts driven by extreme heat events and a lack of rain.

In 2011, the city experienced 40 consecutive days with high temperatures exceeding 38°C (100°F).

Elsewhere, a number of cities have experienced violent shifts towards either a wetter or drier climate in a process called a 'climate flip'.

Overall, 20 per cent of the world's largest cities have experienced a climate flip, with 13 per cent switching to a more extreme wet climate and seven per cent jumping to a dry extreme.

Collectively, cities experiencing a climate flip are home to 250 million people.

Cairo in Egypt, Madrid in Spain and Riyadh in Saudi Arabia were the cities which experienced the most dramatic switch from a wet to dry climate.

In the last 40 years, Cairo has gone from having a wet climate to having an extremely dry climate with long periods of drought.

On the other hand, Lucknow and Surat in India, and Kano in Nigeria have undergone the biggest change from wet to dry.

Once again, it was Asia which has experienced the most dramatic changes in climate over the last four decades.

According to the study, 90 per cent of the top 20 cities experiencing wetting trends and 75 per cent of all wetting cities in the dataset were in South or Southeast Asia.

Likewise, 80 per cent of all cities experiencing a climate flip to wetter extremes and 50 per cent of all cities undergoing climate whiplash are in the same region.

Co-lead scientist Professor Michael Singer, of Cardiff University, says: 'One interesting outcome of this study is how many of the climate hazard trends appear to spread over broad regions.

Professor Singer says this suggests that there may be 'significant adaptation challenges to new hazard regimes but also regional opportunities for collaboration between nations'.

The researchers also calculated which regions are most vulnerable to the impacts of global weirding and least prepared to deal with its impacts.

This analysis showed that hotspots of heightened risk were largely clustered in South and Southeast Asia and in North and Northeast Africa.

Cities identified as the most vulnerable include Khartoum, in Sudan, Faisalabad and Lahore in Pakistan, Baghdad in Iraq, Surabaya in Indonesia, Nairobi in Kenya, and Addis Ababa in Ethiopia.

However, while Europe was not the most affected region, the researchers warn that some European cities may be uniquely vulnerable to the effects of global weirding.

All European cities have become drier, with cities like London, Paris, and Berlin all facing the risk of more frequent and severe droughts.

Madrid, Barcelona, Paris, and Berlin were all among the 20 cities which have experienced the strongest drying trends in recent years.

But they may be much more affected by these changes than drying cities in the USA or Australia due to their ageing water infrastructure.

That makes it more likely that frequent droughts will lead to water shortages and other severe consequences when they occur.

These issues can already be seen in Spain, which has experienced a severe drought for the last four years, withering crops and causing massive agricultural disruption.

At the same time, climate change also increases the risk of severe weather events through a process called climate intensification.

So, when rain does fall it tends to do so in more violent, extreme periods such as that which led to widespread flash-flooding in Valencia last year.

Likewise, in 2023 France was struck by one of its most severe droughts in recent history which led to water scarcity in both cities and rural areas. 

During that year, France experienced its hottest summer on record which pushed two thirds of its natural groundwater reserves below normal levels.  

Research contributor Dr Sean Fox, of the University of Bristol, says: 'As the nature and intensity of natural hazards change, their impacts on urban communities will be significantly shaped by social and infrastructural vulnerabilities.

'In other words, risk isn’t just about the chance of a flood or drought occurring, it’s also about how prepared communities are to deal with these hazards.'