By Paul Homewood

 

Hayley Fowler, Professor of Climate Change Impacts, writes in The Conversation:

“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.

https://theconversation.com/heatwaves-and-flash-floods-yes-this-is-britains-new-normal-121351

Leaving aside the nonsense about by 2080 summers in the UK will be much hotter and drier, for which there is no evidence whatsoever, what about all of this extreme rainfall? Surely with our warmer climate, there should be clear evidence of this already?

Unfortunately for Hayley’s little theory, the data tells us otherwise.

KNMI provide a useful tool for analysing daily data, and below are all of the graphs of daily rainfall for long running English sites, with 100 years of data.

(Question – shouldn’t the Met Office be providing similar data, instead of trying to charge for it?)

http://climexp.knmi.nl/selectdailyseries.cgi?id=someone@somewhere

 

I can see no evidence in any of these plots to support the assertion that rainfall is becoming more intense. These are of course all year round figures, not just summers. But the same argument about “warmer atmosphere” applies just as much in winter. (And has continually been wheeled out every time we get some heavy rain then).

 

Using the KNMI data, I have run an analysis of days with over 30mm of rain at Oxford, which has the longest data record:

 

There was a spate of really heavy rainfall days between 1920 and 1980. Since then there has been no discernible difference from the earlier years in the series.

 

The trouble with climate scientists, such as Hayley Fowler, is that their theories and computer models are all that matter. Hell, if the actual data disagrees, just ignore it!

And the reason is simple. That is her job, to model the impact of climate change on extreme rainfall and its effects.

She is extremely well funded by the European Research Council, the Natural Environment Research Council, the Wolfson Foundation and the Royal Society. Can you imagine that funding still coming in, if she found that climate change will make little difference to extreme rainfall?

No, neither can I!

via NOT A LOT OF PEOPLE KNOW THAT

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August 9, 2019 at 09:09AM