A warmer world will be a wetter one. Ever more people will face a higher flood risk as rivers rise and city streets fill up.
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July 2021: High water on the River Rhine as it flows through
flooded Germany. Image: By Gerda Arendt, via Wikimedia Commons |
In this century alone, the global population has increased by 18%. But the number of people exposed to damage and death by rising waters has increased by more than 34%.
This finding is not based on mathematical simulations powered by weather data. It is based on direct and detailed observation.
Researchers report in the journal Nature that they looked at more than 12,700 satellite images, at a resolution of 250 metres, of 913 large flood events between the years 2000 and 2015.
During those years, and those floods, water spilled from the rivers to inundate a total of 2.23 million square kilometres.
This, considered as one event, would cover a total area larger than Saudi Arabia.
And during those first 15 years of the century, the number of people directly affected by the floods was at least 255m, and possibly 290m.
“Governments across the world have been too slow in reducing greenhouse gas emissions . . . This, alongside the current floods in Europe, is the wake-up call we need”
In those 15 years, the numbers of people in the way of the ever more
devastating floods rose by at least 58m, and possibly as many as 86m. That’s a
rise of as much as 24%.
It will get worse. According to the researchers, climate change and the
multiplication of human numbers will extend the reach of flood risk: 32
nations already experience ever more flooding. By 2030, another 25 countries
will have joined them.
The humans caught up in the sickening flow of mud, sewage and silt spilling
from the rising rivers will mostly be in south and south-east Asia − think of
the Indus, Ganges-Brahmaputra and Mekong Rivers − and many of them will have
migrated to the danger zones: poverty and population pressure will leave them
no choice.
None of this should come as a surprise.
In the past 50 years,
according to
a new compilation by the World Meteorological Organisation, weather, climate and water were implicated in 50% of all disasters of any
kind; in 45% of all reported deaths and 74% of all economic losses.
Floods have claimed 58,700 lives in the last five decades.
Between them, floods and storms − the two are often linked − cost
Europe
at least US$377bn in economic losses.
Higher flooding frequency
And things will certainly get much worse for Europe as global average
temperatures continue to rise in response to ever higher greenhouse gas
emissions from ever greater use of fossil fuels. That is because what had once
been relatively rare events will grow in force and frequency.
More heat means more evaporation, and a warmer atmosphere has a greater
capacity to absorb water vapour. So it will rain harder.
And the
arrival, say researchers in the journal
Geophysical Research Letters, of intense, slow-moving storms that precipitate
devastating flash floods of the kind that swept Belgium and Germany this
summer
will by the close of the century become 14 times more frequent.
“Governments across the world have been too slow in reducing greenhouse gas
emissions and global warming continues apace,” said
Hayley Fowler, a climate scientist at Newcastle University
in the UK, and one of the researchers.
“This study suggests that changes to extreme storms will be significant and
cause an increase in the frequency of devastating flooding across Europe.
This, alongside the current floods in Europe, is the wake-up call we
need.”
Links
- Satellite imaging reveals increased proportion of population exposed to floods
- Water-related hazards dominate disasters in the past 50 years
- Climate change to bring more intense storms across Europe
- Quasi-Stationary Intense Rainstorms Spread Across Europe Under Climate Change
- Death toll exceeds 180 as Germany and Belgium hit by devastating floods
- Record-smashing heat extremes may become much more likely with climate change -study
- Pacific Northwest heat wave 'virtually impossible' without climate change -research
- As floods hit western Europe, scientists say climate change hikes heavy rain
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